THE UNIVERSITY OF ILLINOIS LIBRARY Return this book on or before the Latest Date stamped below. University of Illinois Library L161— H41 THERAPEUTIC IMMUNISATION By the same Author, PULMONARY TUBERCULOSIS Its Diagnosis, Prevention and Treatment. Coloured Frontispiece and 20 Illustrations, Price 6s. net. THERAPEUTIC IMMUNISATION THEORY AND PRACTICE BY W. M CROFTON, M.D. Lecturer in Special Pathology, University College, Dublin ; Visiting Physician, Royal National Hospital for Consumption in Ireland ; Pathologist to Dr. Steevens* Hospital ; late Temp. Capt., R.A.M.C. PHILADELPHIA P. BLAKISTON'S SON & CO. 1012 WALNUT STREET 1918 Prmted in Great Britain K PREFACE. This book contains the substance of the lectures I have delivered annually for the last seven years at University College. There seems to be a general feeling in the pro- fession that vaccine therapy is a comparative failure. The feeling is, I think, justified, and the failure, in ^ my opinion, is due to the fact that the usual practice » is founded on an incomplete theory. I have tried to describe a more complete theory and the practice I have founded on it, a practice that has given and is 3^ giving me highly satisfactory results. W. M. C. University College, Dublin. CONTENTS. CHAP. PAGE I. Introduction i II. Toxins and Antitoxins 12 III. Bacteriolysis and Phagocytosis ... 29 IV. Agglutination, Precipitation, Reactions . 42 V. Therapeutic Immunisation .... 54 VI. Alimentary Canal 71 VII. Respiratory System 103 VIII. Urino-genital System ..... 125 IX. Bones, Joints, Wounds . . • . . 146 X. The Skin 163 XI. Vascular System, Lymphatic System, Ner- vous System, Eye and Ear .... 173 XII. Infections Produced by Streptothrices . 207 Index 221 Therapeutic Immunisation Theory and Practice. CHAPTER 1. INTRODUCTION. Immunity, in the sense in which it is used by bacteriologists, is the term applied to a condition of an animal, such that its tissues cannot be invaded by a given microbe, or if they are invaded the microbe is certainly destroyed by them. In other words, the tissues of the immune animal cannot be broken down by the microbe to form suitable food for itself. Our knowledge of the mechanism which pro- duces this desirable state is as yet far from perfect, but it is gradually advancing, and the application of this knowledge to the immunisation of the patient for prophylaxis and treatment has instituted a new era in medicine. I shall not try to give a comprehensive account of the theories of immunity, but shall only set forth as much as I hope will prove sufficient for the successful appligation of theory to practice. Therapeutic Immunisation. Some general considerations concerning the posi- tion of microbes in the economy of living things is first of all necessary. Microbes are classified as a subdivision of the fungi and are known as ' fission ' fungi or Schizo- mycetes. They are minute unicellular masses of protoplasm, sometimes without a cell wall, some- times with a cell wall of more or less modified protoplasm. They have great facility in adapting themselves to changes of environment and display remarkable powers of self-preservation when cir- cumstances are unfavourable and of reproduction when they are favourable. For our present purpose the Schizomycetes may be classified into three groups, according to their mode of life. I. Saprophytes ; 2. Symbiotics ; 3. Parasites. I. Were it not for saprophytic microbes the supply of inorganic nitrogen in the soil would rapidly become exhausted. These nitrifying organisms, as they are called, by means of their ferments split up dead organic material into its elements. Treating the soil with farmyard manure would be useless if these organisms did not accom- plish this ; for plants can only absorb their nitrogen as simple salts, which they re-elaborate into the large organic molecules, in which form only nitrogen can be metabolised by animals. These nitrifying organisms are made use of by civilised communities for the purposes of sewage disposal. The sewage is exposed to the action of the microbes in special receptacles called septic 2 Introduction. tanks, the clear, inodorous and innocuous effluent from which can safely be run into rivers. 2. Well-known examples of symbiotic microbes are those occurring in combination with algae to form lichens and in the tubercles on the roots of certain leguminous plants. This latter combination furnishes another way in which nitrogen can be fixed in the soil, for it has the power of combining the atmospheric N with O and H to form simple salts. Large tracts of land have been rendered fertile by growing leguminous crops infected with these bacilli. Micro-organisms in the intestinal canal of man and other animals play a part in digestion — for instance, a very important part in the digestion of cellulose. It has been said, too, on a certain amount of experimental evidence, that young animals which have been kept sterile from birth do not thrive so well as those which have become normally invaded by micro-organisms. There are also certain micro-organisms which keep the human vagina sterile by producing lactic acid ; pathogenic organ- isms can, as a rule, only live in an alkaline medium, and so such organisms introduced into the healthy vagina rapidly die out. Milk soured by microbes, which produce lactic acid, is extensively used at the present day to disinfect the large intestine of man ; with excellent effect in many cases. 3. The parasitic micro-organisms are those which most concern us. They differ from the others, in that they have acquired the power of subsisting at the expense of living tissues, first breaking them Therapeutic Immunisation. down by means of certain ferment-like substances which we, speaking from the point of view of the attacked, call toxins. These microbes we speak of as ' pathogenic ' or disease-producing. There are numerous kinds of pathogenic microbes and, like the races of other divisions of living things, different races have adapted themselves to different conditions of environment ; so that one kind of microbe is able to live best on one tissue, another on another tissue, or one species of microbe on some one particular animal or vegetable and not on others. It is therefore obvious that life could not continue if living protoplasm had not the power of resisting this splitting-up-into-elements faculty of microbes. The war continuously waged between nitrifying organisms and the amoeba which inhabit the soil furnishes an illustration of the ' balance ' which is so nicely adjusted between the toxin of microbes and the immunity of protoplasm. The amoeba lives on the microbes, that is to say, they are ingested and digested by it. On the other hand, when the amoeba dies it is split up by the microbes. We can imagine that when an amoeba is young and vigorous it can ingest and digest large numbers of the microbes ; but that when it is getting old it will be able to take up fewer and fewer of them until a time will come when the immunity of its protoplasm will be so reduced that it can no longer resist their lytic powers. No doubt there are also other physical factors which would lower the immunity of the amoeba, with the inevitable consequence. 4 Introduction. This struggle helps us, I think, to realise how much our existence and health depend on the pre- servation of the balance of power. It is thought by some that pathogenic microbes may serve a useful purpose by killing off the feeble members of the community ; unfortunately it is often the most useful members that are destroyed, having perhaps been attacked during a temporary lowering of their resistance or by an exceptionally virulent strain of microbes. It is clear, too, that a pathogenic microbe must be immune to the protecting mechanism of the indivi- dual which it is attacking ; and in certain cases it is quite easy to observe and to effect the increase or decrease of the immunity, or, speaking from the point of view of the attacked, toxicity of a particular strain of microbe. Take, for instance, the case of a typhoid bacillus. When first isolated from a patient suffering from typhoid fever it may be very virulent and strongly resistant to agglutination ; but, when kept alive by transference from one culture tube to another, it gradually loses a large amount of its toxicity and becomes easily agglutinated : it has no longer to kill its food, and therefore the special weapons for this purpose are not developed ; indeed, the special stimulants, viz., the antibodies of the host which caused the increased production of toxins are no longer present. On the other hand, the toxicity of a given strain of microbes can be enor- mously increased by passing them through a series of susceptible animals. In each animal the microbes are attacked by the antibodies of the host, which 5 Therapeutic Immunisation. are not strong enough to kill or permanently injure them ; but after a temporary lowering of the toxin-producing powers of the microbes their proto- plasm responds by producing more toxin than at first. In each animal the microbes receive an additional stimulus until their toxicity is enor- mously increased, it may be to such an extent that whereas a huge number of microbes had to be given to kill the first animal, the injection of a single microbe will prove fatal to the last. This decrease and subsequent increase in virulence is probably one factor in the incubation period after infection. The same phenomenon also serves to illustrate how a susceptible person — for instance, an individual unvaccinated against small-pox — may be a danger to the community, for if he is attacked by the disease he may pass on a much more powerful virus to the people he infects. No hard-and-fast line can be drawn between the saprophytic and the pathogenic microbes, for some microbes which have been leading a saprophytic existence can become pathogenic if the balance is upset in their favour. ' Carriers ' of infectious disease well illustrate this point. During an epi- demic of diphtheria, for instance, many people, who are quite well, harbour virulent diphtheria bacilli in their throats. If their resistance is lowered owing to any of the causes to be mentioned below, the balance is upset by the defective working of the patient's immunising mechanism, and he begins to exhibit the symptoms of the disease. After a time, if the infection does not kill him, his tissues 6 Introduction. respond by making special antibodies and the infecting microbe is destroyed ; or he may only make just sufficient to antagonise the microbial poisons so that there is an exact balance between the immunity of the host and the toxicity of the microbe, the microbe is not killed off, and is capable of giving the disease to another person. Such cases are also common after typhoid fever, cholera, and other like diseases. Another instance of a microbe which is commonly saprophytic, but which can become pathogenic with facility, is that constant inhabitant of the gastro- intestinal tract, the Bacillus coli communis. Turning now to the phenomena of immunity exhibited by the higher animals to microbial disease, we find that certain species or individuals are not susceptible to certain diseases. For instance, the lower animals are not attacked by the gonococcus or by syphilis (except when artificially infected by the latter), while man does not get distemper. Again, certain individuals pass through violent epidemics unscathed, although, as we have seen, they may be actually harbouring the causative microbe. Such species or individuals are said to be ' naturally immune.' This natural immunity varies with different condi- tions. Children, as a rule, are more susceptible to measles and whooping-cough than adults. There are indications that sex may have some influence ; thus, the resistance of females to infection seems to be lowered during the menstrual period. There are certain conditions of environment which notoriously 7 Therapeutic Immunisation. lower resistance to infection, such as chills caused by wet and cold. Draughts invariably cause an attack of nasal catarrh in some people. Alcohol, too, lowers the vitality by dilating the superficial capillaries and causing a rapid radiation of heat, and probably also by directly affecting the immunis- ing mechanisms. There are many other predisposing causes, e.g., grief, hunger, fatigue, bad food, bad smells and certain systemic diseases — for instance, chronic nephritis and diabetes : tuberculosis is a frequent terminal event in the latter disease. Immunity may also be ' acquired ' 1. By an attack of the disease. An attack of typhoid fever commonly leaves the patient immune for a number of years. On the other hand, after pneu- monia immunity lasts a very short time as a rule. 2. By injecting into the patient the blood or blood serum of an animal which has previously been inoculated with the disease. In this case the patient's tissues take no part in the production of the antibodies and the immunity is known as * passive immunity ' ; such immunity is used for the prophy- laxis and treatment of diphtheria and tetanus, for instance. 3. By the patient's tissues being stimulated to take an active part in the production of antibodies. This condition is known as * active immunity.' It may be produced in several ways : — {a) By causing an unmodified attack of disease. This was one of the earliest ways of combating small-pox, one patient being infected from another. It was given up owing to the number of fatalities. 8 Introduction. (b) By causing a mild attack of the disease with a modified virus. Such is the present mode of inocu- lating against small-pox, the virus being modified by passage through the calf. Pasteur used cultures of anthrax bacilli, grown at a high temperature and so modified in virulence, for the prophylaxis of this disease in herds and flocks. He also used rabies virus, modified by drying for different periods. Haffkine's cholera vaccine is made from cultures grown at a high temperature, viz., 39 deg. C. (c) By inoculating the patient with the killed microbe or its toxins. This method is used both for prophylaxis and treatment. Wright has introduced a typhoid vaccine for prophylactic purposes ; it is extensively used with most satisfactory results. The vaccine consists of virulent typhoid bacilli grown in broth and suspended in normal salt solution and killed by heat or, preferably, by antiseptics. Haffkine's plague prophylactic is vaccine made from a virulent culture of the Bacillus pestis and killed by heat. There can be no doubt that vaccines will be and ought to be more extensively used for prophylactic purposes ; for instance, the children of tubercular parents ought all to be inoculated with tubercuKn, and people who have recovered from a disease, such as pneumonia, which leaves them open to another attack, ought to be immunised against the special micro-organisms. For purposes of treatment vaccines are, at present, our most powerful weapon, both in chronic and in many acute infections. 9 Therapeutic Immunisation. After an injection of a vaccine, there is usually a period more or less marked in which the patient's natural resistance to that particular infection is lowered ; this is known as the ' negative phase.' In order to do away with this, or greatly modify it, a dose of specific serum, if available, is given just before or at the same time as the vaccine. In this way the patient is rendered passively immune and also actively immune. Such a condition is called ' mixed immunity.' Already the fact has been mentioned that not only are certain individuals immune to certain microbes, but certain tissues are also. Take, for instance, the tissues seldom infected by the tubercle bacillus. This organism is very fond of the bones, lungs, etc., but it seldom attacks muscles. The gonococcus flourishes as far as the openings of the Fallopian tubes into the peritoneal cavity, but it seldom causes peritonitis. This is known as ' local immunity,' and the instances given are of ' natural ' local immunity. It may also be acquired, tem- porarily at any rate. For instance, it is quite a common experience to see boils retrogressing in one place and progressing at another, and erysipelas spreading, while the tissues behind the spreading edge are overcoming the infection. Passive or active local immunity could only be satisfactorily induced artificially in many cases by injecting the serum or vaccine into an artery going to the part, which, as far as I know, has not been done. In some cases passive immunity can be induced by the local appHcation of the serum, as, for instance, by injecting 10 Introduction. anti-meningococcic serum into the spinal canal in epidemic cerebro-spinal meningitis. Antibacterial serum has also been used locally in diphtheria, and antisera also in inflammation of the stomach. Vaccines have been injected subcutane- ously in such a position that the lymphatics draining that area pass through the affected part. When the different mechanisms of immunity are being discussed it will be possible to consider the relation of these processes to those of ordinary tissue digestion as far as we know them, and I think it will be found that the ordinary antiferments found in the blood — for instance, antitrypsin— resemble in their attributes (for we do not yet know their chemical composition) antitoxins ; and that the process of digestion of foreign proteins, such as foreign red blood corpuscles and certain microbes, resembles very closely that of the tissue digestion of carbohydrates (glucose) and fats. We do not yet know precisely the form in which proteins are absorbed by the tissue cells. II CHAPTER II. TOXINS AND ANTITOXINS. Since we do not know the chemical composition of toxins we must try to define their chemical position by their attributes. The statement was made in the first chapter that toxins were ferment- like substances ; the reasons for this statement must be considered now. All the vital activities of protoplasm, even tissue respiration, have been referred to the action of ferments, so that it cannot be doubted that micro- organisms break down proteins, carbohydrates and other similar substances, by means of ferments, for we know of no other method by which living protoplasm can effect these changes. The question is whether the special substances which some of them have developed and which are able to attack the living protoplasmic molecule are ferments also. These toxins must not be confused with poisonous substances which may be formed by the breakdown of, say, a protein molecule, such as peptone, nitrites and indole, which are ordinary products of meta- bolism. Like ferments, toxins can be divided into two classes : (i) The exotoxins are soluble and can be obtained from the culture medium in which the microbe is grov/ing. (2) The endotoxins are confined to the body of the micro-organism, no toxin being found in the culture medium. Exotoxins, for instance, tetanospasmin, the toxin 12 Toxins. produced by the tetanus bacillus, may be compared with a ferment such as trypsin. The trypsin of the pancreas breaks down the large complex non-diffusible protein molecules in such a way as to render them diffusible and capable of serving as food for the tissue-cells. So, too, the toxin breaks down the large living protoplasmic molecule, making it suitable food for the microbe. For instance, if tetanus spores washed free from toxin are injected into an animal, the spores perish and the animal does not develop the disease ; but if some toxin is injected with them it prepares food for the spores which are then able to germinate and to produce the disease. Ferments are specific in their action. A ferment that hydrolyses a protein will not hydrolyse a sugar, and a ferment that hydrolyses one sugar will not hydrolyse another. This is well illustrated by the stereo-isomeric sugars, ^i-glucose and /-glucose. The former is the familiar dextrose or grape sugar, the latter is said not to occur in Nature. They only differ from each other in the arrangement in space of their constituuent atoms. This is illustrated in their graphic formulae : — HO— C— H H— C— OH COH COH H— d:— OH HO— C— H HO— C— -H CH2OH HO— C— H H— C— OH H— d:— OH ('jHaOH ^-glucose ^f-glucose* 13 Therapeutic Immunisation. The rf-glucose is split up into COg and HgO by glycolytic ferments with ease, the /-glucose, if at all, with difficulty. Fischer compares the action of a ferment on its substrate to a key fitting a lock, the opening of the door which corresponds to the lytic process only occurring when the key fits. The combining group of the ferment must unite with the molecule it is attacking before the ferment can act. The action of pepsin on fibrin may be taken as an example. If fibrin on which pepsin is acting is cooled to a low temperature (o deg. C), then thoroughly washed with ice-cold water to remove all the free ferment, and is then restored to the proper tem- perature (37 deg. C), digestion continues as before, showing that the pepsin that has been acting has remained in chemical combination with the mole- cules of fibrin. Invertase, a ferment which hydro- lyses cane sugar, has also been shown to unite chemically with the molecules of cane sugar before breaking them down. In the same way a toxin does not attack the molecules of a living cell unless it can combine with them. If tetanospasmin is injected into certain animals {e.g,, the tortoise), it can be removed months afterwards from their blood ; it has not been able to combine with any of the cells of the animal, and has therefore produced no symptoms. If, however, it is injected into a sus- ceptible animal, it rapidly combines with cells of the central nervous system, producing the charac- teristic symptoms ; so strong is its affinity for nervous tissue that emulsions of brain substance have been injected into patients suffering from tetanus in 14 Toxins. order to neutralise the toxin that may be circulating. Hens are not susceptible to tetanus because their general tissues have an affinity for the poison and so take it up before it can reach the central nervous system. If it be injected directly into the central nervous system of the hen tetanus develops. In every chemical reaction there is a temperature at which the chemical change takes place most rapidly, and ferments and toxins are no exceptions to this rule. As we have seen, pepsin will not act on fibrin at o deg. C, the optimum temperature for its action being the body temperature. Tetanolysin, a haemolytic substance produced by the tetanus bacillus, unites with the red corpuscles at o deg. C, but will not break them down until the temperature is raised : the most favourable temperature for the action being the body temperature. If a frog is inoculated with tetanospasmin, the poison dis- appears from its circulation, but the animal does not develop symptoms. If, however, the animal's tem- perature is raised to 30 deg. C. for some days, typical symptoms of tetanus appear. It thus appears that both ferments and toxins have two properties, that of combining and, after the union has taken place, of producing their characteristic effects, if the conditions are suitable. Erlich has given names to these two groups of atoms of the toxin and enzyme molecules. The combining group he calls the * haptophore,' the active group ' zymophore ' or ' toxophore.' He conceives the atoms of the protoplasmic molecule with which the haptophore group combines to be Uke the side chain 15 Therapeutic Immunisation. of a benzene nucleus, and he calls them ' receptors/ This is known as the ' side-chain theory.' The toxophore group can be destroyed by certain chemical and physical means without interfering with the combining faculties of the haptophore group ; indeed, there are indications that the com- bining powers of this may be increased. Such altered enzymes or toxins are known as zymoids or toxoids respectively. The chief methods of producing this inactivation are the action of heat, light, oxygen and such chemicals as iodine and carbon bisulphide. Toxoids will cause the formation of antitoxin quite as well as toxins. Both enzymes and toxins are precipitated by the agents that precipitate proteins and destroyed by the agents that destroy proteins. And, although it is extremely hard to obtain ferments in a pure state owing to the fact that precipitated protein absorbs and carries down any ferments and toxins that may be present, yet, the purest ferment that has been obtained, viz., pepsin by Pavlow's method, has a protein-like structure. The same may be said of ricin, a vegetable toxin which is obtained from the castor oil plant and which acts in the same manner as bacterial toxins. However, recent work has sug- gested that the proteolytic ferments and toxins may be of a lipoid nature, or attack the lipoid elements of the protein molecule, the suggestion being made that the protein molecule consists of amino-acids linked together by means of lipoid elements. If these are removed the protein molecule falls to pieces. At any rate, these ferments and i6 Toxins. toxins differ from the higher proteins in being able to pass through an animal membrane or a Pasteur filter, just as peptones can. They also induce anti- bodies, which are different to those induced by the higher proteins. There is one point in which toxins appear to differ from enzymes. The latter, at any rate outside the body, can go on acting indefinitely ; for when an enzyme has broken down the molecule on which it is acting, it is set free to attack another molecule. This does not seem to be the case with toxins ; but then toxins are not attacking inert molecules, but molecules which are possessed of ' life,' and so one would expect that there would be some difference. And again, if a ferment, such as trypsin, is injected into the circulation so as to be under the same condi- tions for action as a toxin, it is likely that the way in which it acts on the tissue cells is similar. At any rate, the tissue cells respond by forming similar antibodies in both cases. Endotoxins. — The majority of pathogenic micro- organisms do not pour forth soluble toxins into the culture media in which they are growing, but it is found that the bodies of the microbes themselves are poisonous, both when alive and when dead. Just as we have compared the exotoxins to the soluble ferments, so we may compare the endo- toxins to the intracellular ferments or endoenzymes. As mentioned above, all the activities of living cells, both of anaboUsm and cataboUsm, have been referred to the action of endoenzymes, even the function of respiration ; so that it is not surprising that the Therapeutic Immunisation. microbial cell has produced a ferment that will attack living jtissues, on which it has to live. In this they are not unique, for do not cancer cells and the syncytium of the chorionic villi do the same ? Although many of these microbes, e.g,, the typhoid bacillus, the pneumococcus, the cholera vibrio, do not produce soluble toxins in vitro under ordinary circumstances, yet in some cases they can be made to do so in the test tube by special means and, undoubtedly, some of them do so in the body. For instance, Chantimesse has obtained a soluble toxin from the typhoid bacillus by growing it in broth made with an extract of the spleen. That soluble toxins are produced from the cholera bacillus in vivo has been shown by Metchnikoff, who intro- duced the virulent cholera vibrios enclosed in a collodion bag into the peritoneal cavity with the result that the animal died of cholera, although no vibrios escaped. The production of toxins soluble but more or less localised to the region in which the microbe is, owing perhaps to the comparatively small amount of the toxin produced, may be induced in some such way as ' hormones ' induce the secre- tion of ferments by the cells of glands, e,g,, just as secretin induces the secretion of the pancreas. The production of Chantimesse's typhoid toxin would certainly suggest something of the sort. With the same object in view microbes have been grown in the blood serum of an immunised animal, so that the antibodies contained in it may stimulate the microbe to produce more toxin. i8 Antitoxins. Antitoxins. As we have seen, toxins, like ferments, induce when injected into the circulation antibodies, that is, substances which antagonise the action of the ferment or toxin, preventing it from exercising its characteristic effect. Such antibodies are found normally in the blood — for instance, antitrypsin ; and there can be little doubt that antitoxins are similar substances. Antitetanolysin occurs com- monly in the blood of horses and cattle, in whose intestines the tetanus bacillus is a common parasite. These antitoxins or antiferments might act in two ways, viz., either by destroying the ' ergophore ' (zymo- or toxo- phore) group of the toxin molecule, or else by uniting with the haptophore group, and thus preventing the union of the toxin with the receptors of the molecules it is attacking. The latter has been found to be the case ; and according to Ehrlich the antitoxin is the receptor or side-chain, that is, the part of the protein molecule with which the toxin combines, which is cast off into the blood and tissue fluids and there unites with the haptophore group of the toxin molecule. As a matter of fact the molecule of antitoxin is much larger than the molecule of toxin, and it is quite possible that one molecule of antitoxin can neutraUse many molecules of toxin. That it is much larger is shown by the fact that it will not pass through an animal membrane or gelatinised Pasteur filter, and, as we know, toxin will. Ehrlich imagines the production of antitoxin somewhat as follows ; Therapeutic Immunisation. a molecule of toxin unites with a receptor, and the molecule of protoplasm finds that it cannot build up the toxin molecule into its substance owing possibly to the absence of a suitable endoenzyme for its destruction ; the presence of the indigestible molecule interferes with the nutrition of the cell — that is, the cell is poisoned. In order to get rid of the indigestible molecule it must cast off the receptor with it, for the two are chemically united. The protoplasmic molecule then replaces the cast- off receptor by a number of similar receptors, which are shed into the tissue fluids. This is quite similar to the process which we imagined to take place in the increase of toxicity of a strain of microbes. The amount of toxin which combines with the living unit must not be so great as to interfere with its nutrition to such an extent as to bring that nutri- tion to a standstill— that is, to kill the unit. The stimulus, in other words, must be submaximal. We see, therefore, that in order that antitoxin may be formed the toxin must be (i) able to unite with certain units of the living molecule ; otherwise the toxin is excreted unaltered and sometimes, as in the tortoise, remains so in the circulation for months ; (2) that the living unit must not contain an intracellular ferment for its digestion; and (3) that the living unit must not be killed. Antitoxic sera for the treatment of human beings are as a rule derived from the horse, and for the following reasons : — I. It can give a large supply of serum without injury to itself. 20 Antitoxins. 2. The serum proteins of it are comparatively little toxic to human beings. 3. The horse is susceptible to most of the diseases for which we desire to obtain antisera. After injecting the toxin, as a rule subcutaneously, there is a latent period of longer or shorter duration. This period is followed by a 'local' reaction con- sisting of a marked swelling and induration round the site of the injection, and a * general reaction ' of malaise, loss of appetite and fever. This reaction lasts for from hours to two or more days, according to the dose and the individual susceptibility of the animal. This period of reaction corresponds to a period in which the resistance of the animal to the disease in question is lowered — the animal is said to be in a ' negative phase ' or in a condition of ' hypersusceptibility.' Even before this negative phase has passed off considerable amounts of anti- toxin have appeared in the circulation. This may seem paradoxical, but we shall see later on that in the formation of immune body there is often a qualitative difference in the immune-body first formed (see p. 39). In the same way the early formed antitoxin may not be so efficient as that formed later on. This ' negative phase ' is followed by a ' positive phase ' in which the animal has an increased resistance to the disease ; and this is found to correspond to an increase in the amount of anti- toxin in the blood. The animal is given increasing doses of toxin during the positive phases, until it develops a large amount of antitoxin and can stand large doses of the live microbe itself. 21 Therapeutic Immunisation. The amount of antitoxin an animal can produce varies with the individual, and it is found that after a certain level of antitoxin production is reached, larger doses of toxin will not further increase the amount of antitoxin in the blood. The amount keeps constant for a longer or shorter time, then gradually falls until there is no antitoxin in the blood at all, although the animal is quite as immune to the disease — indeed, it may be more so. After a long rest such an animal may be induced to form some antitoxin again, but comparatively httle. EhrUch's explanation of this phenomenon of immunity without the presence of antitoxin is that the susceptible cells no longer form receptors for the toxin. But the receptors with which the toxin originally united must have been used for uniting with food atoms of some kind, and it seems unlikely that the living molecules could permanently do with- out these receptors. It seems more in accordance with Ehrlich's theory of nutrition to suppose that the living units have developed intracellular fer- ments to deal with the toxin so that it is no longer necessary for them to cast off the receptor-toxin combination; therefore the Uving units no longer receive the stimulus which induced them to form an abnormal amount of, and to cast off, the ' receptors.' The period of hypersusceptibility, the negative phase, has given a lot of trouble to makers of anti- sera ; for if another injection is given during this period the hypersusceptibility is further increased and the animal frequently dies. We shall see later that the negative phase corresponds to a fall in the 22 Antitoxins. phagocytic power of the leucocytes, and no doubt of the other phagocytic cells ; there is also a leu- copenia, at any rate, in the peripheral circulation. Probably all the tissues participate in this lowering of resistance. It will be useful to state some of the devices used for modifying this period. 1. The toxin is given mixed with antitoxin, or a dose of toxin given in one place and antitoxin in another. There is thus produced a condition of ' mixed ' immunity. 2. The toxin is converted into toxoid by sulphur tetrachloride or iodine in a solution of potassium iodide. As we have seen, toxoids are excellent antigen. 3. What might be called specific toxoids are given. The bacillus — e.g., of diphtheria — is grown in a medium to which a large amount (15 — 30 per cent.) of horse serum has been added. After a time the culture is heated to 65 deg. C. for thirty minutes and then filtered. The altered toxin (toxoid) gives rise to a general but no local reaction. There are many theories as to the exact way in which toxin and antitoxin interact. The subject is a very complex one and need only be treated of superficially here. Diphtheria toxin is considered of normal strength when c.c. will kill a guinea-pig weighing 250 grammes in about four days ; this is the ' mini- mum lethal dose ' (M.L.D.) of the toxin. A unit of diphtheria antitoxin is that amount which will neutralise 100 M.L.D. , that is, i c.c. of it. The 23 Therapeutic Immunisation. quantity of serum that does this varies with each sample of serum ; i c.c. of a serum may contain any- thing from 300 to 1,000 units or more. So for testing purposes the serum is diluted. The union of toxin and antitoxin is a complex one, and it is not easy to account for all the phe- nomena. For instance, take a serum i c.c. of which neutralises 100 minimum lethal doses of toxin, then one would expect that if j^(5% c.c. of antitoxin were added to the 100 M.L.D. of toxin i M.L.D. would be left free and the animal would die in the normal time if the mixture were injected. But it doe3 not ; and it is not until the antitoxin in the mixture is reduced to about c.c. that i M.L.D. is set free and the animal dies. Again, if i c.c. of antitoxin {i.e., 1 unit) is added by degrees to 100 M.L.D. of toxin, no diminution of toxicity is noticed until ^^.s^ c.c. is added, which means that, if less than this '25 c.c. is added, 100 lethal doses remain free and the antitoxin will kill 100 guinea-pigs. Ehrlich supposes that toxin and antitoxin react like a strong acid and a strong base, and accounts for the above phenomena by presuming the presence of other substances in addition to the true toxin. In the first case, just mentioned, he supposes the presence of a substance ioxon, which is not all com- bined until more than c.c. of antitoxin are added ; and in the second case he supposes the presence of prototoxoid , a non-toxic substance, which has a greater affinity for antitoxin than toxin has, and must all be combined before any toxin can be 24 Antitoxins. neutralised. The composition of the toxin might be represented diagrammatically thus : — Proto- toxoid. Toxin. Toxon. It was found, however, that there were many other anomalies of combination in particular cases. For each Ehrlich supposes the presence of a new substance. These need not be mentioned here. Toxon he supposes to be the cause of post-diph- theritic paralysis. Arrhenius and Madsen consider that the inter- action of toxin and antitoxin is like that of a weak acid and a weak base, and conforms to the law of mass action. They take as an example the inter- action of alcohol and acetic acid. In such a mixture there is always some free alcohol and free acid as well as the combination of both, viz., ethyl acetate, and the action is a reversible one. Similarly, in a mixture of toxin and antitoxin there will always be free toxin and antitoxin and the combination of both. It is well known that the reaction of antigen and ferment is a reversible one. There are certain facts for which this theory would well account. For instance, for the fact that active immunity can be produced by a mixture of toxin and antitoxin, that small doses of toxin-antitoxin are innocuous while large doses may be fatal, and that a similar mixture may be fatal to one animal and not to another. It would further explain the death of an animal from the effects of a toxin 25 Therapeutic Immunisation. when the animal akeady has some antitoxin in his blood. Blitz regards the interaction as one of adsorption between colloids, while Bordet thinks it like the absorption of stain by a tissue — the addition of antitoxin rendering the whole toxin less toxic. BUtz's hypothesis is probably nearest the truth. We need not discuss the matter further. It is only necessary to realise that toxin and antitoxin do unite and that the toxin molecule is thus rendered harmless. Now what is the source of the antitoxin ? From theoretical considerations it would appear that any cell with which the toxin combines without destroy- ing it can produce and cast off receptors, that is, antitoxin. Ehrlich at first supposed that antitoxin was only produced by the susceptible cells — for instance, tetanus antitoxin by nerve-tissue cells. It is probable, however, that less poisoned cells would be in a better position to produce the anti- substance, and that certain cells whose business it is to deal with invading micro-organisms would pro- duce more. It is found that more antitoxin is pro- duced if the toxin is injected subcutaneously than if injected intraperitoneally, and more if injected intraperitoneally than if injected intravenously — the same is true of certain other anti-substances, such as complement and opsonins. It would thus appear that the subcutaneous cells may produce more antitoxin than the peritoneal endothelium, and these cells than the vascular endotheHum. However, other factors may yet be discovered to account 26 Antitoxins. for these phenomena. Some facts point to the leucocytes as a great source of antitoxin. When an animal is injected with a toxin, it has a very marked effect on the conduct of the leucocytes, especially the polynuclears. If the dose is an overwhelming one, there is a permanent leucopenia in the peri- pheral circulation until death. If the dose is non- lethal, there is at first a leucopenia, followed, as the negative phase passes off and the positive phase comes on, by a leucocytosis. During the peripheral leucopenia, as Andrews has shown, the leucocytes are concentrated in the internal organs, the liver, the spleen, and especially in the lungs. He suggests that these cells are recuperating, especially in the lungs. The increase in the number of leucocytes runs parallel with the increase of the amount of antitoxin. Metchnikoff has shown that if after injecting a fowl with tetanospasmin an aseptic exudate is produced, the toxin can be recovered from the leucocytes in it. So that since the leuco- cytes take up the toxin they must, if they are not killed, produce a substance to neutralise it. More- over, we shall see later that leucocytes ingest live micro-organisms and digest them, and so must be able to produce antibodies to their toxins. Indeed, we should expect cells with such functions to be specially facile at producing such bodies. We may conclude, then, that phagocytic cells probably produce a large amount of antitoxin. We have already seen that tissue cells themselves can become immune in erysipelas and furunculosis. It is likely that such an organ as the liver, the cells 27 Therapeutic Immunisation. of which have various activities, and which is always receiving small doses of bacterial toxins from the alimentary canal, would be able to produce anti- toxin with ease. We must not forget that small doses of toxin may be dealt with without invoking much special aid. If a small dose is injected there is almost at once an increased blood supply to the part, which dilutes the toxin and thus renders it less toxic for individual cells, and possibly converts it by its oxidising powers into the harmless antigen toxoid. 28 CHAPTER III. BACTERIOLYSIS AND PHAGOCYTOSIS. The way in which the animal organism deals with the microbial cells must now be considered. There are two ways, either of which may act alone, or they may both act together in any given case. In the first the micro-organisms are broken up into their elements by the ferments or ferment-like substances in the body. In the second way they are taken up and digested by the phagocytic cells of the body, viz., the leuco- cytes, especially the polynuclear neutrophiles ; the endothelial cells of the blood-vessels, lymphatics and serous cavities ; the epitheUal plates of the lung alveoU ; the star cells in the liver ; large phagocytic cells in the spleen and bone marrow, and so on. The first method is called bacteriolysis. It was first observed by Pfeiffer, who found that when cholera vibrios were injected into the peritoneal cavity of immunised guinea-pigs they were killed and dissolved very quickly, first becoming immobile, then sweUing up into spherical masses, which became gradually smaller until they disappeared. Bordet furnished the explanation of this ; he found that if cholera vibrios were added to the fresh serum of an immunised animal they became dissolved, but if the 29 Therapeutic Immunisation. serum was first heated to 56 — 60 deg. C, no solution of the vibrios took place, but that if to this mixture of heated, and thus inactivated, immune serum a little fresh serum from a normal animal was added, solution of the microbes took place as before. There must, therefore, have been two substances present, one of which only occurs in the serum of an immu- nised animal and which is not destroyed by heating to 60 deg. C, and the other which occurs in the serum of normal animals and is destroyed by heating to this temperature. The first is said to be ' heat-stable/ and is called variously ' immune-body,' ' ambo- ceptor,' ' substance sensibilisatrice.' The second substance is said to be ' heat-labile/ and is called alexin or complement. Bordet calls the heat-stable substance ' substance sensibilisatrice,' because he thinks that it sensitises the microbes and so enables the alexin or comple- ment to act on it. Bordet also found that the same kind of thing occurred if red corpuscles of another animal were used as antigen, and much research work on the phenomena of lysis has been carried out on red blood corpuscles. For instance, if a rabbit is injected with guinea-pig's corpuscles it will develop substance sensibilisatrice, and if guinea-pig's cor- puscles are added to the fresh immune serum they undergo lysis (haemolysis), the haemoglobin being liberated. If this serum had been previously heated to 60 deg. C. no haemolysis took place until a little fresh normal serum had been added. Bordet, as we have seen, thinks the heat-stable substance acts as a sensitising agent, which further 30 Bacteriolysis and Phagocytosis. can become detached after the complement has united with the antigen. EhrUch, on the other hand, thinks the heat-stable substance acts as an intermediate link between receptor and complement and calls it amboceptor* The heat-stable and heat-labile substances will be referred to hereafter as ' immune-body ' and ' complement ' respectively ; the term ' immune- body ' does not commit one to any particular theory. Immune-body becomes attached to the receptors of the microbes or red corpuscles, for if either are mixed with an inactivated immune serum or with an active serum at o deg. C. and are then centrifuged and washed with normal solution, the corpuscles appear unchanged, but if after suspending them in normal saline solution complement is added haemo- lysis takes place. In this experiment Ehrlich showed that the corpuscles had removed all the immune- body, so that if more corpuscles were added to the original serum they were not sensitised. Ehrlich thus conceives that immune-body had two haptophore or combining groups, one which unites with the cell-receptors the ' cytophile ' haptophore, the other with the complement the * complementophile ' haptophore. He thinks once the combination of receptor, immune-body and complement has taken place that it is permanent, and that even after haemolysis immune-body cannot be recovered or set free again. It has been proved, however, that a certain amount of immune-body can be detached before and after 31 Therapeutic Immunisation. haemolysis, which would tend to support Bordet's ideas. Complement like toxin has a combining (hapto- phore) group and a zymophore. This latter can be inactivated by heat, light, oxidising agents, iodine, and sulphur tetrachloride, and thus the complement is converted into complement oid, just as toxin can be converted into toxoid ; indeed, complement has been called ' animal toxin.' This complementoid can unite with the immune body and so interfere with lysis by keeping out complement. Ehrlich thinks that complement can combine freely with immune-body when it is not attached to a receptor. Bordet denies this. Recent work has demonstrated that complement can itself be further subdivided into two, but it is unnecessary for our purpose to complicate the matter further. Complement can combine directly with antigen at a suitable temperature and the union is a firm one, but no lysis occurs even if immune-body is subsequently added. As we shall see presently, microbes are thus prepared for ingestion by phagocytes. I have stated advisedly that these substances, viz., immune-body and complement, are ferments, for the way in which the solution of these masses of foreign protein takes place is exactly the process by which carbohydrates and fats are split up in the tissues, the tissue-cells providing the complement- like part and the pancreas being, at any rate, the chief source of the immune-body-like part ; these have been, in this connection, called ' ferment ' and 32 Bacteriolysis and Phagocytosis. ' coferment ' respectively. We have no accurate information as to how the large and complicated protein molecule is broken down by the tissue-cells, but I think this process of bacteriolysis and haemo- lysis furnishes a clue to what takes place and would suggest the method of metabolism of all three substances in the tissues is similar. It would also suggest that a chief course of ' immune-body ' for bacteriolysis is the same as the source of the co- ferment for carbohydrates and fats, and this would tend to be confirmed by certain phenomena which take place on inoculation of bacterial vaccines into people with diabetes where the cells of the pancreas which produce the coferments are destroyed or not functioning properly. The immune-body is a strictly specific substance ; that produced by the stimulus of one antigen will act on that substance and no other. In contrast to it complement is much more feebly specific — in fact, many deny that it has any specificity at all ; they say that if an antigen is sensitised, practically any complement will unite and act. It appears, however, that there is a feeble specificity, for if sensitised antigen is added to fresh serum a certain fraction of the complement contained in it is attached quicker than the rest, but that eventually the whole comple- ment is fixed. The amount of this more specific complement is increased temporarily during the process of immunisation of an animal with any given antigen. Muir has shown that complement derived from certain animals absolutely refuses to act with immune-body produced from certain other animals ; 33 ' Therapeutic Immunisation. for instance, horse's complement will not haemolyse ox*s corpuscles when the immune-body for them has been produced by the rabbit. This fixation of complement to antigen by immune-body is utilised for diagnostic purposes ; for if antigen, heated patient's serum and comple- ment are mixed and incubated together and the complement becomes fixed, then immune body for that particular antigen, e,g,, the tubercle bacillus, is present in the patient's serum, and so that patient is suffering or has suffered from that particular infec- tion. The effect of the immune-body-complement combination on the microbe in many cases does not produce lysis of it, but kills it. This is spoken of as a ' bactericidal ' action. The second way in which living microbes are disposed of by the body, viz., phagocytosis, was first observed by Metchnikoff in the amoeba, which he watched engulfing and digesting bacteria ; he also described a similar process taking place in Daphnia, a small crustacean, when infected by the spores of a yeast Monospora, the immunity of the animal to the infection depending on the ingestion and digestion of the infecting micro-organism by the animal's leucocytes. He found that this method of removal of not only living organisms, but also of all sorts of foreign materials, which had got into the body, occurred throughout the animal kingdom, and came to the conclusion that the processes of immunity were the processes of nutrition, a truth which has become and is becoming more and more clear as our knowledge of the processes of nutrition increases. 34 Bacteriolysis and Phagocytosis. Leishman, Wright and Douglas, and following them many others, have worked out the details of this process of phagocytosis and have demonstrated that in the case, at any rate, of pathogenic micro- organisms, a certain preparation of the microbe is necessary before ingestion by the phagocytic cell can take place. Leishman mixed blood with a suspension of micro- organisms in normal saline solution, incubated the mixture under cover glasses in a moist chamber, then made smears of the incubated mixture, stained the films and counted the number of microbes in a certain number of polynuclear leucocytes and took the average. By dividing the average number ingested by the leucocytes in the blood from a normal person into that given by the blood from an infected person, he obtained what he called the ' phagocytic index.' Wright and Douglas, working with staphylococci, improved the technique by incubating the mixture in capillary tubes, and by separating the elements involved in the experiment, found that if the leuco- cytes were washed free from serum before being mixed and incubated with the microbial suspension, little or no phagocytosis took place, so that there must be some substance in the serum which either stimulated the leucocytes to, or prepared the microbes for, phagocytosis. They showed that the substance acted in the latter way, and they called it ' opsonin,' from the Latin word opsono — I prepare food for table. They further found that if the serum was first heated to 56 — 60 deg. C. before being used in 35 Therapeutic Immunisation. the experiment, little or no phagocytosis took place, and they described the opsonin as being heat-labile. They found, too, that this heat-labile opsonin rapidly disappeared on keeping, on being exposed to sun- light and by the action of chemical agents. By means of their technique they were able to follow the fluctuations of the opsonin content of the serum under varying conditions, and by dividing the average number of microbes, opsonised with normal serum, taken up by leucocytes into the average number taken up, which had been opsonised by a patient's serum, they contained what they called the ' opsonic index.' For instance, the average number taken up when prepared by the normal control serum might be 8, while when prepared by the patient's serum it might be 4, then the ' opsonic index ' would be .5. It was found that an index falling between -8 and i-2 might be considered normal, and that if a patient was infected with a given organism this opsonic index to it frequently lay outside these limits, being either low or high, or fluctuating from subnormal to supranormal. It was found, too, that, in such a disease as pneumonia, the index, which during the acute stages was subnormal, would rise suddenly very high just before the crisis. In a subsequent chapter I shall refer to the effect of inoculation on the opsonic content of the blood. Whilst studying the opsonising properties of com- mercial anti-staphylococcic and anti-streptococcic sera I found that, although they might contain none of the heat-labile opsonin described by Wright and Douglas, and, therefore, would produce no opsonisa- 36 Bacteriolysis and Phagocytosis. tion by themselves, yet if some fresh normal serum was added to them much greater phagocytosis was brought about than by the normal serum by itself. I found, too, that the substance in the immune sera producing this effect was not destroyed by heating to 60 deg. C, and I suggested that in these sera the greater opsonisation was produced by the inter- action of two substances just as in the case of bac- teriolysis — in short, that heat-labile opsonin was com- plement, and that the heat-stable was immune-body. Subsequent work by others has confirmed this work, and it is certain that this is one of the methods of opsonisation in immune-serum. I found, too, that there was a small amount of this immune-body to staphylococci and streptococci in my own and other human sera, and this is not surprising, since few human beings escape invasion by these common pathogenic organisms. Again, Neuf eld, working with the serum of rabbits very highly immunised against virulent streptococci, found that there was a substance in it which was not destroyed by heating to 60 deg. C, which would prepare the streptococci directly for phagocytosis without the help of any heat-labile substance. He called this substance ' bacteriotropin,' a term which has been more recently applied to anti-microbial sub- stances in general. This * immune-opsonin,' as it is called, is generally considered to be identical with immune-body, but I consider it far more likely to be anti-endotoxin, for it occurs in the sera of highly immunised animals and complement has no part in its action ; and further it seems reasonable to suppose 37 Therapeutic Immunisation. that if the toxins of the microbe were neutralised phagocytosis would readily take place. The fact that diphtheria antitoxic serum, which may contain no heat-labile opsonin but large amounts of anti- toxin, is a powerful opsonising serum would tend to confirm this view. What I have said above as to the specificity of complement applies to heat-labile opsonin, that is, it is feebly specific, a sensitised antigen removing all the opsonin (as well as the complement, for they disappear together), but some of it is attached quicker than the rest. The inoculation of a given antigen produces a temporary increase of this more specific heat-labile opsonin. On the other hand, the immune-body-like opsonin and the antitoxin-like immune-opsonin are absolutely specific, just as immune-body is and antitoxin is. I conceive that the difference between the opsonisa- tion in normal and immune-serum is this, that when a phagocyte takes up a microbe prepared with heat- labile opsonin, it may be able to digest it, but we know very often it cannot, but is destroyed by the toxin of the microbe, which microbe may thus be deposited in some place where it becomes a grave source of danger to its host (this is certainly one of the ways virulent microbes gain the interior of the body), while in the case of the microbe which has been prepared by the specific opsonising sub- stances the phagocyte can ingest and certainly digest it. From the point of view of prophylaxis and treat- ment the induction of these specific antibodies is of 38 Bacteriolysis and Phagocytosis. the utmost importance for the production of any kind of permanent immunity. They can be increased to a very high degree by steadily increasing the dose of microbial suspension during positive phases. The upper limit varies with the individual. It has been found that the immune-body that first appears in the process of immunisation is of poorer quality than that produced later. It must not be thought, however, that the quality and quantity of the leucocytes is of no importance in the matter. Frequently one finds in opsonic estima- tions that while the majority of polynuclear leuco- cytes have taken up few microbes, others will be found crammed with them, indicating a marked difference in the phagocytic capacity of individual leucocytes. It has also been found that using the same serum and bacterial suspension leucocytes from different individuals differ in their phagocytic capacity. It is well known that it is lowered in certain diseases, such as spleno-meduUary leukaemia. These observations have, of course, only been made with leucocytes, but without doubt the other phagocytic cells vary in their capacity in different individuals. Moreover, of the leucocytes themselves, for most microbes the polymorphonuclear-neutrophile leuco- cytes are by far the most active phagocytes, while the eosinophile cells are the least, the mononuclear taking an intermediate position. Another important factor for successful opsonisa- tion, as for all ferment and anti-ferment action, is 39 Therapeutic Immunisation. the reaction and salt content of the medium in which the action is taking place. It has been shown that if the reaction of the medium is made slightly acid to litmus, phago- cytosis is greatly reduced and an increased amount of acid totally inhibits it. The most favourable reaction is, of course, the faintly alkaline reaction of the normal blood. This may be a factor to be reckoned with and corrected in conditions of acidosis, as in fevers and in such diseases as rheumatism, gout and diabetes. I have noticed abnormal reactions, after inoculation with vaccines, in patients suffering from marked acidosis in diabetes. Acute pyeUtis has rapidly cleared up when the urine has been rendered alkaline, and in treating urinary infections with vaccines the urine must be rendered alkaline during the treatment, unless it is contraindicated by the presence of alkaline phosphate calcuU, where the urine, owing to decomposition, is alkaline already. Too strong a salt solution inhibits opsonisation under experimental conditions, and it is probable that in both lysis and opsonisation the presence of lime salts is essential. There remains the question whether the antibodies mentioned are present in the whole blood as they are in serum. It has been shown that the serum that first is squeezed out when the clot begins to contract is much poorer in opsonin and complement than that which comes out later, and it has been found that very little phagocytosis took place when staphylo- 40 Bacteriolysis and Phagocytosis. cocci were injected into a surviving heart in which no clotting took place. When virulent microbes are injected directly into the circulation, practically no phagocytosis takes place in the circulation, nearly all of it occurring in the spleen, liver, and lungs, and it is in the collecting of the leucocytes, especially of the polynuclear, in these situations that in a great part accounts for the leucopenia in the peripheral circulation after injection of certain micro-organisms. On the other hand, Wright and Douglas found that the opsonin content of citrated plasma was the same as the corresponding serum. I think myself that it is probable that the immune-body and antitoxin circulate as such in the plasma, but that the complement and heat-labile opsonin is cast out by the tissue cells at need. CHAPTER IV. AGGLUTINATION, PRECIPITATION, REACTIONS. We have still to consider two substances occurring in serum of infected or immunised animals, viz., agglutinins and precipitins, whose role in immunity we do not know. Indeed, it is quite likely that the phenomena of agglutination and precipitation are functions of other antibodies of a complement-like nature and not special bodies at all. The phe- nomena are very useful for diagnostic purposes. We will then discuss briefly aggressins and then pass on to consider intravital ' reactions.' Agglutinins. — If the serum of a patient suffering or recovering from typhoid fever, or that of an animal or man who has been inoculated with typhoid vaccine, be mixed with a suspension of the typhoid bacillus, the bacilli are observed under the microscope to approach one another and to become attached by their flagellae ; they whirl round and round as if making frantic efforts to free themselves and then gradually become quiescent as if from exhaustion ; more and more microbes become at- tached until all the microbes are united in clumps and are motionless. In the test-tube the uniform opalescence of the bacillary suspension is observed to become more granular, then flocculent ; then the 42 Agglutination, Precipitation, Reactions. flocculi adhere into masses which sink to the bottom of the tube. The phenomenon which is known as the Widal reaction can also be very well seen by making the dilutions in capillary tubes. This agglutination is brought about by comple- ment-like substances known as agglutinins, which are inactivated by heating to 70 — 75 deg. C, and by the same physical and chemical means as com- plement being converted into agglutinoids which have the haptophore group intact. They are produced by infection or inoculation with certain particulate substances of cellular origin, or by cells themselves, such as microbes, red and white corpuscles and other cells. Agglutinoids have the power of preventing agglutination, owing, apparently, to their more active combining power with the antigen, and of thus shutting out agglutinins. Agglutinins can combine at 0 deg. C, but agglutination does not take place until a temperature approaching the body temperature is reached. It has been found in doing the Widal reaction, for instance, that agglutination may take place when the serum is diluted to i in 10, and so on, when diluted up to, say, i in 100, and then there is a series of dilutions in which no agglutination takes place, but when a higher dilution, say i in 10,000 is reached agglutination again takes place. The explanation of these ' zones of inhibition ' I shall not go into here, but I mention it as it is of practical importance. Agglutinins are not absolutely specific. A 43 Therapeutic Immunisation. typhoid serum may agglutinate the Bacillus coli or the paratyphoid bacillus, but it only does so in low dilution ; for instance, it may clump the typhoid bacillus in a dilution of i in 500 or in i in 1,000, while it will only clump the colon bacillus in i in 10. These are known as ' group reactions,' the microbes, mentioned above, belonging to the typhoid-coli group of microbes. Agglutinins are also found in the serum of indi- viduals who have not been inoculated and have not suffered from the disease ; they have been found in the blood serum of infants. Probably they are produced by autoinoculation — for instance, from the intestine. Horse serum frequently clumps the typhoid-coli group and also the tetanus bacillus, and these are common inhabitants of the intestines of horses and cattle. Each injection of the antigen is followed by a negative phase, and this is succeeded by a positive phase. A marked drop in the amount of agglutinin has been observed to accompany a relapse in typhoid fever. If the bacilli are filtered off from an old typhoid culture and injected into an animal it will produce agglutinin, and if this filtrate be mixed with its antiserum a flocculent precipitate will form. This is known as Kraus' phenomenon. Agglutinins are often used as a test for the degree of immunity, and are sometimes extremely useful for this purpose. Precipitins are produced by inoculation of an animal with solutions of proteins. If the serum of an animal thus immunised and a solution of the 44 Agglutination, Precipitation, Reactions. antigen be mixed together a precipitate forms. One would naturally think that an antibody was formed which caused the precipitation of the antigen-protein, but this is not the case, for it has been clearly shown that the precipitate is so great that it could not possibly be formed from the antigen- protein present. To take an example. One milli- gramme of egg-white interacting with fifty- two cubic centimetres of its antiserum yielded a precipitate weighing 25-9 milligrammes. The supernatant fluid still contained antigen in solution. It is clear that 25 milligrammes of precipitate could not have been formed from i milligramme of antigen-protein. The bulk of the precipitate is added to by adsorption to it of all complement-like substances present in the serum. It appears that the same antigen may act over and over again with fresh additions of antiserum, and seems to suffer little sensible diminution. It will not be necessary for us to go further into the theory of the phenomenon. It is used as a test for the identification of an unknown blood, such as found in a blood-stain. Some remarkable diagnoses have been made by this means. The reaction takes place best at body tempera- ture, and precipitation does not occur if the anti- serum is inactivated by heat. It is found also that if antigen and heated antiserum are mixed together, incubated and then unheated antiserum added, no precipitation takes place. It has been shown that, provided the antiserum is strong enough, it will react with protein taken from alUed species, but it acts far more strongly 45 Therapeutic Immunisation. and in much higher dilution with the antigen pro- ducing it. An antiserum to human blood serum acts very strongly with it, less strongly with the blood serum of monkeys and much less strongly with that of other mammals, and not at all with that of birds, reptiles or fishes. The test is given with very dilute solutions of antigen; a solution containing i — 100,000 of egg albumen has been found to react, as has i — 50,000 dilution of human serum. If a blood-stain has to be tested, it is first broken up and dissolved in normal saline solution and then carefully titrated with various antisera, such as human, bovine, avian, etc. A strong precipitate indicates the identity of the blood. As mentioned above, when a precipitate forms complement is adsorbed or fixed to it, so that if sensitised red corpuscles are subsequently added to it no haemolysis takes place. The presence of a precipitate which may be invisible to the naked eye can in this way be detected. Aggressins. — It will only be necessary for me to briefly refer to substances which were supposed to act on phagocytic leucocytes in a negatively chemiotactic manner ; to these substances Bail gave the name of ' aggressins,' and built up a theory of immunity on his experiments. One would hardly expect that microbes would go to the trouble of making a special substance to act on leucocytes, when they already produced substances, viz., toxins, which must have already an aggressive effect, and it appears estabUshed that Bail's aggressins are really 46 Agglutination, Precipitation, Reactions. either exo- or endo-toxins and that there is no evidence of a negatively chemiot actio effect. I have now described all the immune substances that it is necessary to consider, and will conclude this chapter by describing certain intravital * re- actions ' which are of the utmost importance. They all of them depend on the presence in the blood and tissue fluids of antibodies to the antigen used to produce them. They are all major or minor manifestations of a condition known as anaphylaxis, a term which signifies the opposite of immunity, and was the name given by Richet to an illness, often fatal, produced in rabbits and guinea-pigs by an injection of protein material from sea-anemones, followed by another injection of the same protein at a certain interval. The first or sensitising dose was perfectly innocuous ; the second or assaulting dose, often a smaller one, sometimes caused death in a few minutes. Richet's explanation is that the first dose causes the formation of an antibody, and this reacts with the fresh antigen when injected to form a toxin (apotoxin) which produced the symptoms. This explanation is interesting, for the symptoms of anaphylaxis are very like those of peptone-poisoning, and it may be that the protein is broken down by the action of complement and immune-body (ferment and coferment) with the formation of a peptone-like body. Since the symptoms of anaphylaxis in a rabbit are more like those in a human being than those in a guinea-pig, they will be described somewhat in detail. 47 Therapeutic Immunisation. The rabbit may be sensitised by giving 5 c.c. of the foreign protein {e.g., blood serum) per kilo of its body-weight. When a well-marked amount of anti- bodies are present, viz., immune-body and pre- cipitin, a small dose, say 0 3 c.c, of the antigen is given. It has been found that the severity of the symptoms is proportional to the amount of antibody present. Sometimes within fifteen seconds after starting to give the assaulting dose intravenously the ears are seen to flush and the veins to pulsate, the breathing is shortened and there are periods of apnoea : this phase lasts from two seconds to one minute and is followed by marked anaemia and cyanosis of the ears. It is most difficult to get the veins to bleed, and the blood that does flow has a prolonged clotting time, the respirations become panting and heart-beats extremely rapid. The animal is restless and appears anxious. In two or three minutes muscular weakness appears, the animal lies prostrate and unconscious, with flaccid muscles and distended abdomen with relaxed muscular walls. Urine and faeces are discharged. In five to ten minutes this stage of depression is at its maximum, and rapid death may occur, pre- ceded by convulsions. The heart keeps beating for several minutes after the loss of the corneal reflex and the cessation of respiration. In non-fatal cases {e.g., when little antibody is present) there may be only transitory anaemia of the ears and dyspnoea, the animal rapidly recovering ; or the animal may be unconscious for half an hour 48 Agglutination, Precipitation, Reactions. and recover in a couple of hours. If it does recover it is immune for one or more days, and is then as susceptible as ever. If the injection is given subcutaneously, there is severe oedema around the site of the injection. During the illness there is a marked leucopenia in the peripheral circulation. This is not due to a sudden destruction of the leucocytes, but to the fact that there is an enormous concentration of them in the capillaries of the lungs, liver and spleen, and also to the engorgement of the portal veins. There is marked spasm of the bronchioles. The clotting time of the blood in the veins is prolonged and there is a very marked diminution of complement-like substances in the blood. As I have already said, it is owing to the develop- ment of this hypersensitiveness that treatment of chronic diseases with sera given subcutaneously or intravenously is unsuitable. I myself have had a very unpleasant experience in treating a case of tuberculosis of the lungs with an anti-tubercular serimi. The patient had had a number of intra- muscular injections. After the tenth she got very ill ; when I saw her about six hours after she had a giant oedema from her hip, where the injection was given, to her shoulder, her pulse was fast and thready, she was cyanosed and had dyspnoea, this state of collapse gradually passed off and the oedema gradually disappeared. Two other cases of severe anaphylaxis occurred in my practice; the serum was being given intravenously for the treat- ment of pulmonary haemorrhage. In neither case had 49 4 Therapeutic Immunisation. the patient any knowledge of a previous injection of serum. Before 0*25 c.c. had been given the patients began to sniff owing to nasal irritation and within a few seconds were in a state of collapse with dilated pupils, thready feeble pulse and severe dyspnoea. The first case developed congestion of the lungs from which he died in ten days. In the second the symptoms were rapidly relieved by two 0*5 c.c. doses of pituitrin given subcutaneously. Pituitrin also rapidly relieves serum rashes. These cases were probably due to partial digestion of the proteins by the tryptoid ferments which were allowed to act by the destruction or removal of antitrypsin by some method not yet explained. Another interesting case of anaphylaxis was related to me by a colleague. A lady who had had a sub- cutaneous injection of anti-diphtheritic serum for prophylactic purposes noticed that a lump remained at the site of injection. About a week after she struck her hip at the site of inoculation against a chair and the lump disappeared. A short time after she was cyanosed and collapsed with severe dyspnoea, in a typical and alarming state of anaphy- laxis. Such an accident could not have occurred if the serum had been given intravenously, or if toxin had been used (see p. 105). Anaphylaxis sometimes occurs in the use of vaccines ; this is especially the case with those which most easily undergo lysis, such as typhoid vaccine. I have never found it of importance in practice, but it has been produced experimentally in animals. There are many explanations given for the condi- 50 Agglutination, Precipitation, Reactions. tion, e.g., severe shock to the central nervous system — it is said not to occur if the animal is anaesthetised with ether before giving the assaulting dose. Liberation of a toxin — the condition is very Hke that seen in peptone poisoning. Formation of a precipitate. Fixation of complement throughout the system by the sensitised antigen, and so on. All the symptoms could be explained by any of these hypotheses. Anything that would affect nutrition would be felt first, or rather first exhibited, by the nervous system, and fixation of complement- like ferments, which are essential to cellular- nutrition, must, however slightly, affect such highly organised and sensitive cells. Moreover, this fixation can take place either to sensitised antigen or to a precipitate. In the case of an antigen such as typhoid vaccine, whose lysis would liberate a toxin, an additional poisonous factor is added. The literature and experiments on this subject are enormous. But I think I have now mentioned as much of the subject as is necessary for practical purposes. Most of the skin reactions for diagnostic purposes are ' local ' manifestations of anaphylaxis ; they have been chiefly used for the diagnosis of tubercular disease. The local reaction may be due to fixation of complement affecting the nutrition of the cells locally or to lysis of the microbial protein liberating endotoxin. Anyhow, it does not take place unless antibodies to the particular antigen are present. Calmette's conjunctival reaction occurs if a drop of glycerine-free old tubercuhn (AT) (see p. 216) 5^ Therapeutic Immunisation. is dropped into the conjunctival sac of a tubercular patient. There is redness and swelling of the caruncle and mucous membrane, coming on generally within twelve hours when the reaction is positive. If it fails the first time, one is directed to do it again in the other eye. I do not think this is logical, as the first dose might have sensitised the patient. The test has been given up to a large extent owing to the fact that it has been done on inflamed conjunctivae with, in some cases, subsequent sloughing of the cornea necessitating removal of the eye. Von Pirquet's test is done by rubbing old tuber- culin into the Malpighian layers of the epidermis after rubbing off the horny layers. A positive reaction is indicated by an area of swelling of the skin with a brighter red colour round the abrasion. A control mark is also made into which no tubercuKn is rubbed. Some use a series of dilutions from, say, 10 per cent, to lOO per cent., and say it gives them an indication of the amount of antibody present. The test is not given in acute miliary tuberculosis nor in the last stages of the disease ; the same remark applies to all these tests. In Moro's test the tubercuUn is diluted with an ointment and is rubbed in ; red papules indicate a positive reaction. Another method is to make a small blister, remove the raised epidermis and apply the tubercuhn to the raw surface. Yet again, it has been injected into the skin with a needle and syringe. Except in young children none of these tests are 52 Agglutination, Precipitation, Reactions. very reliable. Since we have all been infected with tuberculosis on reaching adult years, a healthy adult without antibodies to the tubercle bacillus must be a curiosity. As a rule a negative reaction is of more importance than a positive one. A col- league of mine, a robust, healthy pathologist, did Von Pirquet's reaction on himself and got a most violent reaction. Similar reactions have been tried for the diag- nosis of other diseases, such as typhoid ; Widal and other such reactions are far more satisfactory. 53 CHAPTER V. THERAPEUTIC IMMUNISATION. , Having now, sufficiently for our purpose, con- sidered the different immunity mechanisms, we shall in this chapter consider how this knowledge can be applied to the prevention and treatment of infections. Therapeutic inoculation falls, naturally, under two heads, viz., (i) The production of passive immunity by means of antibody-containing sera of animals immunised against the disease and (2) the induction of active immunity by inoculating the patient with killed suspensions (vaccine) of the microbe itself more or less modified. A combination of the two processes is of great advantage in certain cases. The production of passive immunity can be used both for treatment and prophylaxis. Sera con- taining antitoxin for the toxin of the diphtheria bacillus and of the tetanus bacillus are used for both purposes, and these sera are efficient. The other sera in use are bacteriolytic or bacteri- cidal and are usually anti-endotoxic as well. As a whole they are not so satisfactory as the antitoxic sera, but brilKant results are sometimes obtained. For prolonged treatment all sera have the dis- 54 Therapeutic Immunisation. advantage that when given intravascularly or subcutaneously the patient often becomes hyper- sensitised to the protein contained in them, with the consequent production of rashes and other anaphy- lactic symptoms, so that unless given via a mucous membrane it is better to confine their use to acute infections. They are to be obtained commercially for the treatment of many of the common patho- genic micro-organisms, such as the staphylococcus, various strains of the streptococcus, pneumococcus typhoid bacillus, and the meningococcus. They are produced, as a rule, by inoculating the animal at first with small doses of the killed microbe ; these doses are gradually increased until the animal can eventually stand a large dose of the live microbe. The efficiency of these sera depends on the amount of anti-endotoxin present, for a dose of serum con- taining only bacteriolytic immune-body may in certain conditions, e.g., typhoid fever, do harm, owing to solution of bacilli and a liberation of a large amount of endotoxin, which would further poison the patient. Active Immunity. — Active immunisation for pro- phylaxis and treatment is becoming more and more extensively used. The production of active immunity for prophy- lactic purposes appears at once to be a logical and useful procedure. Such vaccines are used in the prophylaxis against various diseases, that is, active immunity is produced in the person who may be exposed to the disease ; one, two or more increasing doses are given which stimulate the antibody power 55 Therapeutic Immunisation. of the subject for a certain time and may tide him through an epidemic. This method is now extensively used against the typhoid bacillus, the bacillus paratyphosus A and B, the various dysentery bacilli and the bacilli of plague and cholera, and other epidemic infections, and I use it against the tubercle bacillus. On the other hand, the reasons for the inoculation of a patient, who is already suffering from an infection, with more of the virus of that infection are not so obvious and the procedure puzzles the minds of many. It seems to me that it is best to look at the matter in the following way, viz., that in the majority of infections not all the tissues of the body which are capable of producing antibodies are producing them, and that by inoculation these tissues are made to take their proper share in the fight. Even in acute septicaemic infections, such as typhoid fever, it has been conclusively proved that the subcutaneous tissues are capable of stimulation. No doubt the actively phagocytic endothelial cells of the blood-vessels, which control the passage of substances into the tissues, play an active part in the protection of the tissues from circulating toxins and microbes. The whole question of recovery or not in these acute generalised infections depends, I think, on whether these tissues have been sufficiently protected to be capable of further response. If they are not or are only capable of very little, then the only hope for the patient is the use of antibodies produced by another animal, or perhaps the use of specific antitoxic or germicidal drugs, such as 56 Therapeutic Immunisation. iodine or sulphur. It thus appears that the prog- nosis in acute septicaemic infections depends on the endotheUal cells. When the infection is very virulent their resistance is destroyed ; they are broken down with the appearances of haemorrhages into the tissues. These haemorrhagic forms of acute infection are almost invariably rapidly fatal, for instance, black small-pox, and the like. In acute cases the initial dose must be small, as a rule, so that little or no free toxin must get into circulation and so produce a negative phase. When the infection is strictly localised the rationale is not so difficult to understand, for the fact that it is localised presupposes a certain amount of resistance on the part of the patient's organism and of the tissue in which the infection is. The disease is more or less shut off by granulation tissue and the other processes of inflammation which prevent to a greater or less extent the escape of microbes, their toxins and the products of the tissues broken down by their action, into the general cir- culation, but are not quite capable of absolutely destroying the microbes. The leucocytes that do attack them are rapidly killed, for while they may be able to ingest the microbe which has been pre- pared by the normal opsonising action of comple- ment, yet owing to the absence of specific antibodies they are not able to digest them and are thus killed and form pus, the fluid part of which is found very poor in antibodies. It is difficult for fresh anti- bodies to get into an abscess cavity, owing to the back pressure of the increasing amount of fluid produced 57 Therapeutic Immunisation. by increasing liquefaction of the tissues by ferments. So that in treating a locaHsed infection, if an abscess is present it must be evacuated so that the effete fluid, in which the antibodies have been used up and which contains tryptoid ferments from the killed leucocytes, may be got rid of and fresh antibody- containing serum allowed to flush the infected area. It is necessary to get as clear a view as we can of what takes place in the subcutaneous tissues, at the site of injection, in the organism as a whole, and in the infected tissues. The phenomena that take place are known as reactions and are called ' local,' ' general ' and ' focal,' according as they occur at the site of injec- tion, in the whole system, and at the site of infection. Any or all of these may be absent or so slight as not to be apparent. When the dose is moderate the local reaction is often clinically absent or merely amounts to a slight tenderness, sometimes with a little redness or swelling. The changes in the subcutaneous tissue are those of the early stages of inflammation, viz., increased blood supply and oedema never going on to formation of granulation tissue or suppuration. Since there is practically always present a certain amount of specific immune-body (coferment) for all the common micro-organisms, especially if the patient is already infected, the micro-organisms probably undergo lysis, either in the subcutaneous tissues or in the lymphatic system, at any rate to a certain extent, with the liberation of their endotoxin. If the dose is very minute it is likely that little or 58 Therapeutic Immunisation. none of the bacterial protein and endotoxin gets into the general circulation, the protein being absorbed and digested and anti-endotoxin being produced, but in greater quantity than is necessary to antagonise the amount of antigen injected, so that this sub- stance is poured into the general circulation. If the dose is larger bacterial protein and endo- toxin escape into the circulation with the production of a general reaction. The symptoms of a general reaction vary in degree from a transitory feeling of tiredness to well- marked malaise, headache, fever, pains in joints, and rapid pulse. This general reaction passes off after a longer or shorter time and is perhaps followed by an increased feeling of well-being, if the dose has not been too great. These symptoms are accompanied by changes in the leucocyte and ferment content of the blood in the peripheral circulation. The injection of a moderate dose is followed by a drop, or 'negative phase,' in both the number of leucocytes and in the amount of complement-like substances in the peripheral circulation. This is followed by a positive phase, in which all are in- creased ; this increase lasts a longer or shorter time, and then returns to normal. There is no exact relation between the number of leucocytes present and the amount of complement. The fluctuations in the amount of heat- labile opsonin has been worked out by Wright and others, by means of the ' opsonic index,' which, as we have seen, is obtained by comparing the average number 59 Therapeutic Immunisation. of microbes taken up by polynuclear leucocytes in a mixture containing washed leucocytes, patient's serum and microbes, with the average number taken up in a preparation containing standard serum. It has been found that by increasing the dose during a positive phase it is possible to increase the opsonic index to several times the normal, and in Wright's method of inoculation, the ideal is to attain a dose of vaccine which will keep the patient's opsonic index as high as it will go until the patient is well. In many cases this plan succeeds, in other cases it is partially successful, while in others it fails. I think that many of these last two classes can be made successful if another plan of inoculation is adopted and it will be well to criticise briefly the opsonic index plan of treatment. The opsonic index has been attacked as being uncertain and unreliable in its results. I think that done by the same hands in the same way it gives reliable results. But it has been found that using the technique of Wright and Douglas it is only possible to force it up to a certain height, any further increase of dose not affecting it.* A comparatively small dose will effect this, a dose which is generally too small to induce sufficient specific antibodies to cure the patient in all but very recent infections. And yet we know that, by steadily increasing the dose, more and more specific antibodies, such as immune-body (coferment for the digestion of the protein of the microbe) and anti-endotoxin appear, ♦ To get a true measure of the heat-labile opsonin a dilution method must be used. 60 Therapeutic Immunisation. and I have already shown that these increase phago- cytosis of microbes and their intracellular digestion. One cannot say in any given case the dose which will have to be attained before the patient is well. For diagnosis a high, low, or fluctuating opsonic index is sometimes valuable. For spacing doses, if one was in doubt it may also be valuable, for it is better to give the injection when there is plenty of complement. But as a guide to the amount of the dose it is unsuitable, for it does not indicate the amount of specific antibodies present. As a rule, the more recent and unlocalised the infection the smaller is the dose that need be attained. In the more chronic and localised, one may have to attain very large doses. For instance, I have had to work up to 30,000 million in a case of chronic staphylococcal infection. Focal reactions are produced at the site of infec- tion after the injection of a vaccine. Some unaltered virus reaches it through the circulation and increases the poisoning of the tissue cells at the part and the virulence of the microbes present and so leads to increased inflammation. If the dose has been properly chosen, this is followed by a subsidence of the symptoms, since the general positive phase has occurred and the poisoned part is flooded by a large amount of new antibodies. The increased inflammation may be so slight that it does not give rise to symptoms, only the decrease of these being noticeable. Focal reactions are thus most useful in the cure of the condition. 61 Therapeutic Immunisation. It is by the extent of the local, general and focal reactions, especially the latter two, that we judge the spacing and amount of our doses. I will here give three examples of types of cases to illustrate the above considerations. First, the acute, in which there is a general septi- caemia. In this case one's ideal is to make a certain amount of antibodies and to give such doses as will effect this, without any free toxin getting into the blood. The doses must then, as a rule, be small. The effect of these injections is often magical. Whenever possible it is well to give a dose of appropriate antiserum, in order to produce a mixed immunity, viz., passive and active. The general rules for the spacing of doses in these cases is as follows : — If the temperature falls at once after a dose, give the next dose when it begins to rise again. If there is no effect on pulse and temperature, give the next dose in twenty-four hours. If the temperature and pulse rise, one must wait until the reaction is over, that is, until the tempera- ture and pulse fall and begin to rise again before giving the next dose, which should be a repetition of the last dose if the reaction is severe. Such reactions can be controlled by the injection of some form of iodine, such as iodoform or Szendeffy's combination of iodine, menthol and radium. Iodine, as we have seen, is an antitoxin of the best kind. The second type is a more recent and localised, more or less acute condition, such as an acute conjunctivitis produced, for instance, by the pneumo- ^2 Therapeutic Immunisation. coccus. Such a case might be expected to get well by regulating the size of the doses by means of the opsonic index. Personally, I find that if this is done a fair proportion of cases will relapse ; and I therefore prefer to follow the plan of steadily increasing the doses until the patient is well and then giving two or more doses of the series in order to leave a margin of safety. The last type is a chronic, very localised infection such as chronic eczema or acne. A very large dose may have to be reached before such cases are cured. The initial dose varies (i) with the microbe used ; (2) with the general condition of the patient ; (3) with the age ; (4) with the site of the lesion. If one finds that after the first dose there is too violent a reaction one waits until the reaction has passed and then gives, perhaps, the same dose again, or a smaller dose and works up. Some patients are very sensitive at first, and the dose must be very slowly increased. Later, as they gradually make more antibodies the doses may be more rapidly increased in size. A good rule about spacing the doses is not to give the next one until three clear days after all signs of reaction, local, general or focal, have disappeared. Children will, as a rule, require a smaller dose to begin with and elderly people also, and in the latter one has sometimes to be cautious about increasing the dose, for I find that one cannot always attain to doses that one can in the case of younger patients. I make it a rule not to give an injection during the few days before and during the first few days of 63 Therapeutic Immunisation. menstruation; reactions are likely to be more severe at this period. The best places to inoculate are the dorsum ihi, parts below the clavicle and on the back into the loose fold of skin behind the axilla and between the scapulas. There is frequently a certain amount of local tenderness and the injections should be given where they will least interfere with the patient's movements. I have a distinct preference for the dorsum ihi, the chest and the axillary fold, especially the first. I think the arm is a bad place ; there is not much subcutaneous tissue and the arm is constantly moved. One must also be careful to avoid getting the injection beneath the aponeurosis covering the muscle ; this causes considerable pain at the time of injection and great stiffness for some days after. And lastly, the injection must not be given so that the vaccine will pass through lymphatic glands that are already poisoned by the infection, e,g,, if the infection is on the leg, do not give the injection in the gluteal region of that side. If the infection is in the chest, give it in the gluteal region. If the infection is in the abdomen, inoculate in the chest or back. It is better also to change the site of injection each time. I generally alternate the sides, giving on one side one injection and on the other the next. Let us always keep clearly in our minds the anti- bodies that one desires to produce, and let us review them again briefly. They are : — Opsonins. Heat labile, compound and heat 64 Therapeutic Immunisation. stable. Heat labile are complement-like and feebly specific. The heat stable part of the compound opsonin is absolutely specific, as is the heat stable opsonin, which I beUeve to be anti-endotoxin. Bacteriolytic and Bactericidal Bodies. — These consist of immune-body, which is specific and of complement which is non- or feebly specific. This substance may be a danger if given in serum in certain general infections, owing to the liberation of endotoxins, if anti-endotoxin is not present in sufficient quantities. The compound opsonin and these substances are probably identical. Antitoxins. — If sufficient anti-exo or anti- endotoxins are present in the body for any given microbe, that microbe cannot possibly live in the body. In most infections all three processes take place, more or less, leading, as we have seen, to efficient phagocytosis. ; while in a few cases, such as that of infection by the cholera-vibrio, the immunity is chiefly bacteriolytic and antitoxic. In acute infections it is generally only necessary to temporarily increase the heat-labile opsonin and produce a small amount of specific antibodies. In chronic infections it is often necessary to produce a large amount of specific antibodies, and this is attained by steadily increasing the dose of vaccine until sufficient for the case is produced. We see, then, that in order to succeed in curing one's patient the patient's tissues must be capable of reacting, the doses of vaccine must be given at proper intervals, which are determined by the 65 Therapeutic Immunisation. quality of these reactions, and a sufficiency of specific antibodies must be produced in the patient. Besides these several further things are essential for complete success. (a) The antigen (vaccine) must be adequate — that is, must be of good quality and must contain all the microbes causing the disease, if the infection is mixed as it so often is. We cannot expect to produce suitable anti- bodies for the microbes invading the patient if the antigen given does not contain identical material, e.g,, protein and toxins. {b) The physiological derangements of the patient should be restored as far as possible to normal so that the tissues may be in the best possible condition for producing the antibodies for their action on the microbes by the various phagocytic cells. (c) For a completely ideal result the infected tissues must be capable of restoration to normal. We have already seen (Chapter I.), owing to the rapidity with which microbes reproduce themselves, how quickly they can adapt themselves to their environment and how often they lose their virulence (capacity for breaking down living tissues) when leading a saprophytic existence, and increase it when passed through a series of susceptible animals. The fact that a microbe has invaded a patient and survived shows that it has completely adapted itself to that particular host, which means that its fer- ments can break down that host's tissues. These ferments, however, might be quite helpless against 66 Therapeutic Immunisation. the tissues of another host. So that while the antigen may contain microbes identical with the microbes invading a patient it may not contain the qualities necessary for success unless it is isolated from the patient himself. This point is well illustrated by the meningococcus and pneumococcus, where the antiserum produced by one strain is quite helpless against the bodies and toxins of another strain. To overcome this antisera are produced by antigens containing microbes from as many strains as possible and stock vaccines contain microbes from many sources. Stock vaccines of some microbes, e.g,, staphylococci, the typhoid bacillus, and the tubercle bacillus, can often be used with success, provided an accurate diagnosis of the invading microbe has been made, provided they are made from recently isolated microbes on suitable media, and provided a suitable dosage is used. Too often, however, they are made from old laboratory strains, are spoiled in their manufacture and suitable series of doses are not obtainable commercially. Moreover, they are constantly used without any bacteriological diagnosis having been made. Furunculosis is not always produced by staphy- lococci. Acute urethritis is not always caused by the gonococcus. Further, while a primary infection is caused usually by a single infection, very con- stantly, as we shall see in succeeding chapters, the tissues whose resistance is thus lowered become invaded by other microbes, so that the infection is a 67 Therapeutic Immunisation. mixed one. It is impossible to accurately provide for these varying secondary invaders in a stock vaccine, and yet it is essential for success that the vaccine should contain them. Otherwise the case may be made worse instead of better because the resistance of the infected cells is lowered during the negative phase to all the infecting microbes, and if this is not compensated by the arrival of specific antibodies for a particular infecting microbe that microbe may be left with increased virulence while the phagocytic powers of the body-cells for that microbe are diminished. Microbes being so rapidly and readily influenced by environment it is most important that they should be grown on a medium as nearly as possible like that of the host. This is best attained in the case of human cases by adding fresh human blood pre- ferably that of the patient, to the culture medium in the proportion of about i c.c. of blood to lo c.c. of medium, solid or liquid. It is most important also that the medium should not have been heated to more than loo deg. C. in manufacture in order that the vitamines, which are as necessarj^ for the welfare of the microbe as for higher forms of Hfe, should not have been destroyed and that it should be made from fresh meat. Media made on these hues will grow practically all pathogenic microbes, even the most difiicult, such as the meningococcus, so that a causal microbe is not likely to be missed owing to its failure to grow. Stock vaccines have been prepared in several different ways, some being composed of suspensions 68 Therapeutic Immunisation. of living microbes modified in virulence by con- tinuous sub-culture, growing at a high temperature or other way, or live suspensions sensitised with immune-body have been used, as have dead sensi- tised suspensions. I have not found that these sensitised vaccines give any better results than the ordinary killed suspensions, and the sensitisation greatly complicates the manufacture and adds to its expense. Live vaccines are supposed to increase the quality of the immunity produced. The evidence on this point is quite inadequate and is more than counterbalanced by the greatly increased risk. Suspensions of microbes in '5 per cent, phenol in •9 per cent, sodium chloride recently isolated on media manufactured as described and containing fresh human blood have given in my hands entirely satisfactory results, and in my opinion any further complication is undesirable and unnecessary. It is of the greatest importance that the reaction of the blood and tissue fluids should be normal, so that the processes of nutrition may proceed effectively and the production of antibodies and their action be efficient. Owing to the over-production of acid products of metabolism and their deficient oxidation the normal mechanism by which abnormal concen- tration of hydrogen ions in the system is corrected is constantly upset in disease. This is best combated by giving disodium hydrogen phosphate or sodium citrate. Very frequently, too, in chronic infections the internal secretions of various glands is deficient as well as the various hormones acting on the glands producing the exoferments of the intestinal tract. 69 Therapeutic Immunisation. Opotherapy is exceedingly useful for the replacing or substitution of these. It is generally assumed that the therapeutic immunisator has no use for the older methods of therapeutics, mechanical, pharmacological, and so on. If anyone who practises the former methods assumes such an attitude he will frequently severely handicap himself in the treatment of his patient and is just as fooHsh as the physician who takes the opposite point of view. While it is impossible, with few exceptions, to effect the replacement of destroyed tissues, yet con- stantly the destruction can be limited to such an extent that the tissues destroyed will not be missed or, at any rate, can be done without, even if the patient may suffer physiologically for the rest of his life, as when nerve cells are destroyed. The great aim of medicine must be to prevent the invasion and damage of vital organs by microbes, an ideal the methods for the accomplishment of which will be especially dealt with in succeeding chapters. 70 CHAPTER VI. ALIMENTARY CANAL. There is no need to labour the importance, to the well-being of the individual, of keeping the gastroin- testinal in good working order. Owing to the constant ingestion of food, the gastrointestinal tract is peculiarly liable to infections which may be con- tained in it (the food), and the more distant parts of it can be infected by swallowing of pathogenic microbes, when these are causing lesions of the mouth and respiratory passages. Further, it is the home of certain micro-organisms, which are so con- stantly present as to be considered normal. Such are the Bacillus coli communis, streptococci, and certain anaerobic bacilli. We know that microbes are con- stantly passing through the intestinal wall into the radicals of the portal veins and lymphatics, being carried through by leucocytes which are carrying foodstuffs in ; such microbes have been found in distant parts of the body. This may be useful in keeping up the immunity of the individual to these intestinal microbes, so long as the microbes passing through are of low virulence or a virulent. We know from experience, however, that if the normal resist- ance of the intestinal cells is lowered, these normal intestinal microbes are capable of becoming patho- genic, and such microbes, getting into the circulation, may produce a general infection. This lowering of 71 Therapeutic Immunisation. resistance may be brought about by too much or unsuitable food, which may directly injure the mucous membrane or suffer abnormal decomposi- tion by micro-organisms, putrefactive or otherwise, with the production of poisonous substances, which may also poison the organism as a whole. In this way a vicious circle is set up. Again, the resistance of the mucous membrane may be lowered by the swallowing of pathogenic micro-organisms, so that very many of the infections of the intestinal tract are mixed ; while the stomach may be invaded by microbes ascending from the intestine. Other causes of lowered resistance will be considered when dealing with the different regions of the tract. Acute Infections. Typhoid and Paratyphoid Fevers — The Entericas. — These conditions are general infections, but as most of the symptoms point to the intestines, it is convenient to deal with them here. The symptoms, physical signs and lesions produced by the typhoid and paratyphoid bacilli A and B are practically identical ; indeed the condition may be caused by a mixed infection with the two organisms. Pathology,- — There is a general gastroenteritis with superficial necrosis of the lymphoid tissue of Peyer's patches produced by blocking of their afferent arterioles. The ulceration may be so deep as to pro- duce perforation of the intestinal wall and invasion of the peritoneum. The specific infection is aided in its depredations in the intestine by the ordinary 72 Alimentary ,Canal. microbial inhabitants of the patient's intestine becoming pathogenic owing to the lowered powers of resistance of the tissues. The gall bladder and spleen, which latter is usually enlarged, are favourite habitats of the typhoid and paratyphoid bacilli. Acute bronchitis is common in the disease. There is a poly nuclear leucopenia. Bacteriology. — The typhoid and paratyphoid A and B bacilli are morphologically indistinguishable from each other. In the tissues they are short, stout bacilli 2 — 3 in length and o*6— 0*7 /x broad with rounded ends. In culture they vary in size from cocco-bacilli to long filamentous forms. They are all motile (as a rule), flagellated and decolourised by Gram's method. They can be distinguished from each other by cultural reactions and agglutination tests. The chief sugar reactions are shown in the following table : — Glucose Lactose Saccha- rose. Man- nite. Dulcite. Litmus Milk. Typhoid . A. A. — or A., then AUc, no clot. Paratyphoid A. A. G. A. G. A. G. A., no clot. Paratjrphoid B. A. G. A. G. A. G. A., then Alk., no clot. A. = Acid. A. G. = Acid and Gas. Alk. = Alkaline. The microbe can be isolated from the blood, urine, or faeces. Much the quickest method of diagnosis is the isolation of the microbe from the blood. This can be done in the majority of cases 73 Therapeutic Immunisation. if the culture is taken during the first few daj^s of the illness or at least before the temperature begins to fall. Much the best medium to use is steriUsed ox- or sheep- bile, to which the blood withdrawn from a vein in the anticubital fossa is added. The bile culture is subcultured on to ordinary agar ; the microbe obtained is diagnosed by sugar and agglutination tests with specific sera. If the microbe does not appear on the first sub- culture the process of subculturing should be persisted in daily for a week before giving up hope. If the patient has diarrhoea the microbe can be isolated easily on differential medium, such as McConkey's, but if constipated the colon must be cleaned out by enemata and the liquid faeces obtained after a saline purgative used for culturing. After a varying time the serum of the patient strongly agglutinates the causative microbe (Widal test). Prophylaxis, — A great decrease in the case incidence and a marked decrease in the mortality has been brought about by prophylactic inocula- tion. The method is used in armies and those going to tropical countries. The usual practice is to give 500 — 1,000 units of typhoid vaccine as a first dose and 1,000 — 2,000 units ten days after. As a rule there is little or no reaction. In some indi- viduals, however, there is severe malaise, rise of temperature, swelling, and pain at the site of inoculation. Wright, who introduced the method, uses strains of microbes which have been reactivated by passage through guinea-pigs. Personally, I prefer to use the first subculture of a strain re- 74 Alimentary Canal. activated by growing in broth, to which fresh human blood has been added. The subcultures on agar plates are grown for twenty-four hours, and the suspensions in -5 per cent, phenol saKne are counted on Thoma Zeiss slides. The '5 per cent, phenol in the saline solution kills the typhoid bacillus, as a rule, in a day or two. Further, since there is a great lia- bility to paratyphoid fever, vaccines of paratyphoid A and B are now generally given at the same time. I use for the first dose 500 million each of para- typhoid A and B, followed by double this dose in five to twelve days, according to the reaction. Treatment. — The treatment of typhoid and para- typhoid fevers by vaccine has not been so firmly established as has its use for prophylaxis, although good reports have been published of its influencing the course of the disease in the direction of lowering the temperature and lessening liability to relapse, especially when used early in the disease. This is probably due, as already mentioned, to the fact that, when the resistance of the intestinal tissues is lowered by the typhoid bacillus, the coliform and, probably, other microbes present become patho- genic a mixed infection results. These microbes increase the ulceration produced by sloughing of Peyer's patches and may bring about perforation. Coliform bacilli can frequently be isolated from the urine as well as the typhoid bacilli and paratyphoid bacilli in the entericas. My practice is to give a mixed vaccine containing the patient's typhoid or paratyphoid bacilli and his B. coli in equal proportions. In two bad cases of paratyphoid 75 Therapeutic Immunisation. B fever, one of which had been a week ill, the other three weeks, the pulse and temperature were normal at the end of twenty-four hours, and delirum and other symptoms had disappeared. In three cases of typhoid fever in different stages the temperature came down to normal and remained there after the second injection of mixed vaccine. The vaccine must be autogenous. The initial dose is 2j millions, and the sequence 2|, 5, 7|, lo, and so on. The vaccine should be continued until all the typhoid or paratyphoid bacilli have disappeared from the urine and faeces. The injection should be given sub- cutaneously on the upper part of the chest. The general principles for giving vaccines in acute injections should be followed (see p. 62). In the treatment of carriers several thousand million may have to be attained and any other microbe present, such as the B. coli, included in the vaccine. Antityphoid sera are chiefly bacteriolytic and, instead of being of use, may even be dangerous, as they bring about a large amount of lysis of bacilli in the body with liberation of their toxins, and so the patient may be overwhelmed with toxin, since there is not sufficient antitoxin present to neutra- lise it. Cholera is an acute gastroenteritis caused by cholera vibrio. Owing to copious watery evacua- tions, the system becomes rapidly depleted of fluid and the specific gravity of the blood becomes abnormally high. The microbes are said to undergo rapid lysis in the blood stream, and so cannot be 76 Alimentary Canal. isolated from it. They are, however, excreted in the urine so that there must be a septicaemia. Pathology. — The lesions are most marked in the lower part of the ileum and are those of serous enteritis. There is desquamation of the superficial epithelium and coagulation necrosis of the villi with shght infiltration of the mucosa with leucocytes. Bacteriology. — The cholera vibrio is a small curved motile bacillus with one or more fiagella at one or both ends. It is i*5 — 3 \x in length and 0*5 — 0*6 broad. It is Gram-negative. Its toxin outside the body appears to be an endotoxin, but the experi- ment already cited (see p. 18) points to the proba- bility of an exotoxin being produced in the body. Its lysis in the blood must of course liberate its endotoxin. According to some authorities most of the poisonous effects are produced by its manufac- ture of nitrites in the intestines. Diagnosis is made by isolation of the microbe from the stools. Their identity is confirmed by agglutination tests, Pfeiffer's phenomenon, or complement fixation. Treatment : Prophylaxis. — Haffkine's methods are the best known. In his former method the first two injections consisted of usually J of an agar slope culture 10 c.cm. long of low virulence. The lowering of virulence was brought about by Repeated sub- culture and growth at 39*6 deg. C. The final dose was \ of an agar slope culture, 10 c.cm. long of an exalted strain. His present method is to give 0*5 c.c. of a suspension of an agar slope culture of a virulent strain suspended in 5 c.c. of sterile water. The 77 Therapeutic Immunisation. exaltation of the virulence is brought by 20 — 30 passages through guinea-pigs. The immunity lasts on an average about a year. The method has greatly reduced the case incidence and has had some effect on case mortality. Vaccines do not appear to have been used in the treatment. Probably in most cases the disease is too overwhelming. However, vaccine ought to play a useful role in clearing up carriers. Attempts have been made to produce efficient anti- endotoxicsera by various methods of breaking up the microbes before inoculation ; their use combined with symptomatic treatment (hypertonic salt solu- tion, etc.) has given encouraging results in some cases. Epidemic Dysentery is, as a rule, caused by B. dysenteries. Shiga, Flexner Kruse and others have isolated similar bacilli differing somewhat in cultural characteristics and in their serum tests. But very many other micro-organisms are capable of producing epidemics of acute gastroenteritis, such as the Bacillus pyocyaneus, Morgan's No. i bacillus, B. enteridis of Gaertner, and other members of the typhoid-coli group. The acute outbreaks of diarrhoea that occur on sudden changes of tempera- ture in the spring and autumn are probably due to the ordinary coliform microbes of the intestinal tract, which increase in virulence when the resistance of the intestinal tract is lowered. Pathology. — As a rule the onus of the infec- tion is in the lower part of the ileum and colon. The mucous membrane is intensely swollen, infil- trated with inflammatory cells, while, here and there, haemorrhages occur and it is covered with 78 Alimentary Canal. blood-stained mucus. The infection may be so severe that the whole membrane may slough, and the infection may penetrate to the peritoneum. Bacteriology. — The B, dy sentence is a small rod- shaped, non-motile non-flagellated, Gram-negative microbe, I — 3 in length. In culture filamentous forms develop. None of the varieties isolated ferment lactose, their other sugar reactions are often variable and the identity of the various strains are best ascertained by agglutination with specific sera. This table contains the chief sugar reactions of typical members of four strains. Glucose Lactose Saccha- rose. Maltose Man- nite. Dulcite. Litmus Milk. B. Dys. Shiga A. A., then Alk. Flexner A. A. A. A., then Alk. Y A. A. A., then Alk. Strong A. A. A. A. A. A., late Clot. A. = Acid. Alk. = Alkaline. The toxin of Shiga's bacillus is an endotoxin which is unusually thermostable. It has been obtained by allowing cultures to undergo autolysis, by grinding, and other methods. Powerful agglutinating bac- teriolytic and antitoxin sera have been produced. In acute cases the microbe swarms in the stools, the diagnosis of type being made by cultural characteristics and agglutination tests. In chronic cases and carriers isolation may be more difficult, 79 Therapeutic Immunisation. but agglutination of laboratory strains by the patient's serum is helpful, agglutination in a dilution of 1*50 being a diagnostic. The microbe has also been isolated from the blood and urine. Treatment : Prophylaxis, — Various sera have proved their value for prophylactic purposes, both in the laboratory and in practice, but o^ving to the possibility of sensitising the patient with consequent anaphylaxis if the patient should develop the disease and serum is used it is much better practice to use vaccine for this purpose. This has been done on a large scale by Shiga and others, various types of vaccine — ordinary, sensitised, and so on — being used. Shiga's vaccine is made by suspending a twenty-four- hour agar slope culture in 5 c.c. normal saUne, and heating to 60 deg. C. for an hour. The dose begins with '05 c.c. and rises to '5 c.c. ; by this method he has largely reduced the case mortaUty, but has produced less effect on the case incidence. Shiga, Kruse, and others speak highly of the excellent results produced by the use of serum in acute cases. Probably the results would be greatly improved if the serum treatment were combined with autogenous vaccine from the whole growth from the patient's stools. The vaccine should be continued until all bacilli disappear from the faeces. As one would expect, serum is of little use in the chronic cases. Here vaccine has been most successful. Undoubtedly, as in other intestinal infections mixed autogenous vaccine should be used. This method should also be used in non-specific dysen- teries. In those due to coliform microbes I generally 80 Alimentary Canal use an initial dose of 2| million. It is better to give the inoculations subcutaneously on the chest. Regional Infections. Pyorrhoea Alveolaris. — This condition is an inflammation of the gums around the teeth, varying in intensity from slight catarrh of the tissue in the small normal groove between the apex of the gum and the teeth to complete destruction of the bony alveolus with consequent falling out of the teeth. In some cases the soft tissues of the gums are swollen and spongy, and on pressure pus wells up around the tooth, in others the soft tissues are destroyed as well as the bony alveolus, the tooth becoming ' stripped.' The condition is most important, as it is so common. The constant swallowing of pathogenic micro-organisms infects the whole gastrointestinal tract ; further, microbes infect the blood stream through broken blood vessels and lymphatics, and so any tissue in the body may become infected from this source. Bacteriology, — Many different kinds of microbes have been isolated from the pus. The infection is commonly a mixed one, the most usual combina- tion, in my experience, being microbes belonging to the Micrococcus catarrhalis group and streptococci. Staphylococci of various sorts, bacilli related to Friedlander's pneumobacillus. Gram negative bacilli, morphologically like the influenza bacillus, but differing from it in its profuse growth on blood-agar, are also common. I have found the Bacillus fusi- formis involved with other microbes in several cases. T.I. 8i ^ Therapeutic Immunisation. The diagnosis of the causative microbe is made by (i) Making smears of the pus and staining by Gram's method ; (2) Making cultures on blood- agar. If the smear shows the presence of the Bacillus fusiformis cultures must be made on glucose agar and grown anaerobically. Cultures may be made from the fang of a root or of a hopelessly loose tooth or, faiUng this, a small firm platinum loop is passed down into a pocket alongside a tooth and jigged about until blood appears. The loopful of blood and pus is inoculated on to a plain agar slope. The amount of blood in the loop is sufficient so that a special blood-agar need not be made. As a rule a good growth results in 24 or 36 hours. The different colonies that grow are picked off for investigation and subcultured on to blood-agar. TreaUnent. — It is of course impossible to save teeth from falling out when the destruction of the alveolus has gone beyond a certain point, but it is remarkable how teeth tighten up sometimes. It is necessary to invoke the aid of a painstaking dentist who must remove tartar with meticulous care, split down pockets in order to drain them and level up a tooth which is projecting beyond its fellows and is thus exposed to abnormal shocks and so on ; even when many or all the teeth are hopelessly loose and have to be removed, a course of vaccine therapy is indicated, for it is seldom indeed that the disease has lasted for such a time without causing lesions in other tissues, and that it is the source of infection in many diseases of these tissues there can be little or no doubt. 82 Alimentary Canal. The disease is constantly present in diabetes mellitis, pernicious anaemia and most of the chronic infections of the gastrointestinal tract. It is constantly present in diseases of the spleen, such as Banti's disease and spleno-meduUary leucaemia, the etiologies of which are at present obscure. It is seldom one finds a case of rheumatism without it ; it is often present in phthisis and chronic bronchitis. It may also be the source of origin of the microbes producing rheumatic fever, endocarditis and acute and chronic nephritis. In many of the diseases mentioned I have produced focal reactions by inoculating the patients with vaccines made from microbes isolated from their gums. For most combinations of microbes found I begin with a dose of 2 J million of a vaccine containing the isolated microbes in equal proportions, the usual series being 2|, 5, 7I, 10, 15, 20, 30, 50, 75, 100, 200, and so on to 1,000. I seldom like to stop before 800 — 1,000, as this dose usually guarantees against relapse. I have often had to attain very much larger doses, 10,000 miUion or more. The general rule applies, viz., that there is no fixed upper limit of dosage for any case, each must be worked out on its merits. If a staphylococcus is isolated I begin with 25 miUion of it, the series being 25, 50, 100, 200, 400, 600, and so on up to 4,000 or more but for most combinations 2| millions is the best initial dose. The intervals depend on the reaction and the size of the dose. Usually a few days is sufiicient between the lower doses, gradually extending to a week or ten days between the larger. I usually give the doses 83 Therapeutic Immunisation. on the dorsum ilii unless there is reason for not doing so, such as a rheumatic joint in the lower limb. The vaccine treatment of pyorrhoea alveolaris is most satisfactory as a rule. Infective Gastritis is brought about as a rule by the swallowing of pathogenic microbes con- tained in infected material from the nose tonsils or mouth. So that in any case of gastric indiges- tion such a source of infection should be looked for and, if present, it is more than probable that the microbes causing it are the cause of the gastritis. In some cases the infection spreads upward from the intestine. It is commonly thought that the hydrochloric acid in the gastric juice offers complete protection from the action of pathogenic micro- organisms. Even during the height of digestion it is probable that when mixed with the food the amount of hydrochloric acid does not rise above 0*1 per cent., and this strength is quite inadequate to kill most microbes during the time it is in contact with them in the stomach. In the intervals of digestion hydrochloric acid is not produced and, therefore, there is no inhibition of the action of any microbes that may be swallowed. Pathology. — Infective gastritis may be acute or chronic, the latter often being a sequel of the former ; acute exacerbations of the chronic form are common. In the acute there are the usual changes seen in inflammations of mucous mem- brane, viz., swelling and redness of the mucous membrane with mucus lying on its surface. This has entangled in it leucocytes, desquamated epithe- 84 Alimentary Canal. Hum and red blood corpuscles. The secretory cells of the glands are cloudy and desquamated, while there is small round-celled infiltration between them. The blood-vessels are congested and there may be capillary haemorrhages. The lymphatics may also show desquamation of their endothelial cells. In the chronic cases there are minor degrees of those changes, while if the inflammation is long con- tinued there is an increasing degree of fibrosis of the membrane. The gastric juice is absent completely or partly and the condition is aggravated by the abnormal decomposition products produced from the food by microbes. Bacteriology. — The diagnosis of the causative microbes may be made by plating out material from the stomach itself during fasting by passing down a small bucket attached to a flexible steel ribbon, the whole being enclosed in a rubber tube ; when in the stomach the bucket is pushed out, by means of the ribbon, from the end of the rubber tube, a sample of the infected mucus is obtained and the bucket drawn back into the tube before being withdrawn. As a matter of practical experience most cases of gastritis also suffer from intestinal inflammation, so that if cultures are made from the faeces and from the source of infection above one is certain to obtain the right microbes. Since streptococci are the most common causes of lesions in the mouth, throat and respiratory passages, they are the most common causes of gastritis, but any of the microbes producing these conditions may be causative. The B, coli sometimes spreads up 85 Therapeutic Immunisation. from the intestine. Various saprophytic microbes, e,g,, sarcinae, may aggravate the condition by produc- ing abnormal decomposition of foodstuffs. Prophylaxis, — Prophylaxis consists in clearing up the sources of infection and so preventing infected material reaching the stomach. Treatment. — The quickest way of relieving the symptoms of acute gastritis is by giving the patient normal horse serum or any other antiserum ; anti- diphtheritic serum, even if out of date, does very well. Ten c.c. of normal horse serum disguised in a little milk given by the mouth when the stomach is empty the first thing in the morning every twenty four hours quickly reheves the symptoms. Whether it acts in a germicidal manner or by increasing the resistance of the cells by improving their nutrition, has not been ascertained. As soon as a vaccine is ready it should be used, the serum being continued if necessary. If the vaccine consists of the ordinary catarrhal microbes 2| millions is the ordinary initial dose. If, as is usually the case, intestinal inflammation is also present, or if the B. coli has invaded the stomach 2| millions of this vaccine should also be given. The usual sequence is 2| + 5 + 5> 7i + 7h 10 + 10, 15 + 15, 20 + 20, 30 + 30, 50 + 50, 75 + 75* + to 500 + 500 or more. In acute cases it may not be necessary to push the dose very high, but in chronic cases high doses may have to be reached before the infection is got rid of. It is best to inoculate the patient in the upper part of the body. Of course, appropriate diet and other symptomatic treatment is of the utmost importance. 86 Alimentary Canal. Gastric Ulcer. — The cause of this condition is obscure. Personally, I am of the opinion that most cases are infective in origin and have the same etiology as infective gastritis. In severe cases of this (gastritis) the mucous membrane may slough, and it seems reasonable to suppose that in general inflammation of the stomach the inflammation may be more severe in one place than another and so lead to localised necrosis partly due to direct action of microbial toxins on the cells and partly due to interference with the nervous and blood supply of the area. If the rest of the mucous membrane has not been involved or if the inflammation in it sub- sides the action of the digestive ferment on the tissues infected may aggravate the condition ; in this way what is known as a peptic ulcer may arise. It is doubtful if the pepsin could attack living cells. Pathology, — If the ulcer is seen in the recent acute phase there are evidences of acute inflamma- tion, but as usually seen the peptic ulcer is oval terraced, narrowing to its base, making it funnel shaped ; on section there is a certain amount of infiltration with leucocytes, some fatty degenera- tion and proliferation of the endotheKum of the blood vessels. This endarteritis may be caused by poisons or microbes in the circulation and so pro- duce ulceration. This is generally thought to be the origin of the ulcers of the stomach and duo- denum that follow burns of the skin. If the ulcer is very chronic there may be a great deal of fibrosis, and the stomach may be adherent to adjacent parts. Bacteriology. — See under gastritis. 87 Therapeutic Immunisation. Treatment. — The treatment is exactly the same as for gastritis {q.v,). The serum treatment is par- ticularly effective in bringing about rapid heahng and stopping haemorrhage, while immunisation removes the cause. Surgical interference is only necessary if the ulcer has produced mechanical obstruction, if there is perforation or if the ulceration has opened into a large blood-vessel. Duodenum. — Lesions of the duodenum are of particular importance because (i) in its mucous membrance is produced the hormone or hormones essential for the working of the pancreas ; (2) in it, as in the upper part of the jejunum, is also produced the enterokinase, without which the protease of the pancreas cannot work ; (3) into it open the ducts of the liver and pancreas, up which infec- tions are liable to spread and infect these essential organs. Etiology, — The cause of infections and ulcer of the duodenum are the same as in the case of the stomach with the almost constant addition of intestinal micro-organisms which spread up when the resistance of the duodenal tissues has been lowered by the primary infection. As in the case of the stomach, unsuitable food, or food improperly prepared by the stomach, or hyperacidity of the chyme, act as predisposing causes if the infecting microbes are present, and in this case microbes capable of becoming pathogenic have always easy access to the duodenum from lower down the intestine. Treatment, — The treatment is exactly the same as in the case of the stomach, serum being used for 88 Alimentary Canal. the rapid amelioration of the symptoms, while the infecting microbes are isolated from the mouth or respiratory passage and from the stools, and vaccines prepared. If examination of the faeces indicates imperfect digestion produced by pancreatic or hepatic insuffi- ciency it is well to replace the absent secretions. The Pancreas. — The pancreas being essential to proper preparation of the food for absorption by the tissues and also for the digestion by the tissues of the absorbed foodstuffs it is of the utmost importance to keep it undamaged. Inflammation of the inter- acinar connective tissue involves the cell islands of Langerhans, where most probably the coferments or internal secretions for the metabolism of carbo- hydrates, fats, and very possibly, for that of pro- teins, are produced. Once these cells are damaged they can never be replaced. No other cells of the body seem capable of taking on their functions, and they are comparatively few in number for the production of these so essential substances. Pathology, — In acute general infections, such as typhoid fever and pysemia, the secreting cells have been seen in a state varying from cloudy sweUing to fatty degeneration and necrosis, while there is a round-celled infiltration in the interstitial tissue. I have seen a case such as this in which sugar appeared in the urine. In other cases of septicaemia, and in cases where the gland becomes infected by extension from the stomach, kidney, or other adjacent tissue, there maybe general suppura- tion of the gland, and localised abscesses, or destruc- 89 Therapeutic Immunisation. tion of blood-vessels may give acute haemorrhagic pancreatitis. By far the most common forms of pancreatitis are the chronic. This may arise as a blood infection, as in the chronic septicaemia, which often occurs in pyorrhoea alveolaris and chronic inflammation in the gastrointestinal tract or the infection may spread up the ducts. Very frequently, no doubt, both sources of infection are present. Two types of inflammation have been described : (i) intralobular and interacinar, involving the cell islets, and (2) the interlobular ; the former may be a sequel to the latter. In the inter- acinar type there is small round-celled infiltration of the connective tissue which gradually passes into fibrosis. The small round cells may invade the cell islets or they may be destroyed by the contraction of the newly-formed fibrous tissue. In other cases the onus appears to fall on the islets themselves, which may be poisoned by circulating toxins, under- going various degenerations, e.g., hyaline or fatty. In the ascending inflammation there is infiltration followed by fibrosis round the ducts, and between the lobes and lobules, and the interacinar tissues may escape. Bacteriology. — The microbes causing the lesions in acute septicaemia, as in typhoid fever, staphy- lococcal septicaemia, and rheumatic fever, are easily isolated. In chronic septicaemia it will usually be found that they are derived from areas of local infection, such as post-nasal catarrh, pyorrhoea alveolaris, tonsillitis, chronic entero-colitis. The causative microbe can sometimes be isolated from 90 Alimentary Canal. the blood or urine. As we have seen, there are many microbes capable of producing these lesions, and it may be assumed, as a rule, if these lesions are present, as they practically always are, that some or all of these microbes are causing the inflammation in the pancreas. Probably more commonly the infection spreads up the pancreatic ducts, the infection being derived from the microbes causing duodenitis. Inflamma- tion in the duodenum may cause obstruction of the combined opening of pancreatic and bile duct, or a gallstone in the bile duct or ampulla of Vater may produce this result. Bile injected experimentally into the pancreatic duct has produced inflammation of the pancreas. Chronic inflammation of the duct may produce phosphatic calculi in it and bring about partial obstruction. In these cases the intralobular connective tissue is involved last. As we have seen, the causes of the duodenitis are swallowed microbes, while intestinal microbes may spread upwards. So that the causa- tive microbes can be isolated from these sources. That this is the case it is open to any one to prove by producing focal reactions with vaccines made from microbes isolated from these sources. This reaction is easily followed in diabetes, where an injection of vaccine is almost invariably followed by an in- creased excretion of sugar, often accompanied by a sHght tenderness over the pancreas. Prophylaxis. — Since the pancreas is probably irretrievably damaged when symptoms appear it is of the utmost importance to prevent the infection. 91 Therapeutic Immunisation. Except in acute septicaemias this ought always to be possible. The clearing up of the sources of infection when they occur will absolutely prevent the inflammation. An intestinal vaccine should be used if there is any sign of intestinal derangement. Treatment, — If the inflammation has not gone much beyond the ducts it can be quite cleared up with vaccines made from the two sources of infection. If the destruction has gone to the extent of involving the cell islets, with the appearance of sugar in the urine, it is only very exceptionally that the pancreas can be sufficiently restored so as to cause this symptom to disappear with an ordinary diet. A few cases of diabetes in cases of furunculosis have been recovered by clearing up the furunculosis with staphy- lococcus vaccine. It is known, too, that the removal of the source of infection such as a gangrenous limb has also caused the sugar to disappear. As a rule, however, the pancreas is irretrievably damaged, and it is only possible to prevent further destruction. It is particularly difficult to sufficiently immunise diabetics. They get general and focal reactions with doses that would have little effect on other patients. This is probably owing to the pancreas being an important source of immune body or cofer- ment. It is consequently necessary to begin with a much smaller dose, to increase the dose slowly, and it is in my experience impossible to push the dose beyond a very low maximum. In the most common case where the vaccines consist of Micrococcus catarrhalis and streptococci from the gums and coliform bacilli from the intestines, an 92 Alimentary Canal. initial dose of i + i, followed at suitable intervals by 2 + 2/3 + 3, 4 + 4, 6 + 6, 8 + 8, 10 + 10, and so on, if possible. I find I cannot usually get much beyond the latter dose. I have never entirely cleared up the pyorrhoea alveolaris of a diabetic, but I have very greatly improved it, and the patients have all improved in general health. Of course, pancreatic extract must be given to supple- ment as far as possible the diminished pancreatic secretions. In the ordinary cases of chronic pancreatitis, where there is no symptom of involvement of the intra- lobular tissue the usual dosage may be used. In the case of the microbes given above and for practically all microbes from these sources, 2| + 2j, 5 -f 5, 10 + 10, and so on, as in the case of duodenitis, may be used. In typhoid and other septicaemias the method of dosage recommended in these infections should be used. The Liver. — The Uver can be infected by (i) direct extension; (2) through the hepatic artery; (3) through the portal vein; and (4) by extension up its ducts. It probably can deal better than most organs with micro-organisms, for it must constantly have them carried to it by the portal vein. Whether the liver cells can ingest and digest microbes is not known certainly, the star cells of Kupffer and the various endotheUal cells can, and it is well known that in general infections, such as typhoid fever, microbes are excreted in the bile. The liver seems to have a special faculty for recovery from destruction of 93 Therapeutic Immunisation. its cells, for destroyed cells seem to be replaced by proliferation of surviving cells. It is surprising, too, how comparatively well the individual can remain when his liver is badly damaged as in cirrhosis. Acute inflammation occurs in the course of general infections, such as typhoid fever, puerperal septicaemia, and the like. In chronic inflammation the usual source is infection from the portal vein, which is probably the cause in ordinary cirrhosis, or by extension up the duct. Pathology, — In general infections the parenchyma cells may be in a condition of cloudy swelling, with their cells undergoing fatty degeneration or necrosis, and there is round-celled infiltration in or about the portal canals and between the liver cells. Abscess formation may occur by direct extension of infection, by infection through the hepatic artery, portal vein or bile ducts. It is nearly always secondary to suppuration elsewhere. Chronic infection leading to interstitial hepatitis and cirrhosis takes place through the portal vein. This is probably predisposed to by abnormal amounts of poisonous substances produced by abnormal breakdown products of foodstuffs by microbes. The catarrhal inflammation of the intestine and the cirrhosis may be predisposed to by the ingestion of abnormal amounts of irritants, such as alcohol. Bacteriology, — As the liver inflammation is secondary to infections elsewhere the micro- organisms producing these will be the cause of the liver condition. Prophylaxis, — Cirrhosis of the liver could probably 94 Alimentary CanaL be prevented by clearing up the catarrh of the intestine. Chronic infection via the portal vein or bile duct could be prevented in the same way. Treatment. — Nothing special need be said about the treatment of the liver infections by vaccines, as they are always secondary and the microbes must be isolated from the source of the infection. Nor is there any modification of the course of inoculation to be observed on account of the liver being involved. The Gall Bladder and Bile Ducts. — Chole- cystitis and cholangitis are most commonly pro- duced by infection ascending from the duodenum. In certain cases they are produced by microbes excreted by the liver. This occurs frequently in the ent ericas. The gall bladder and ducts may, of course, also be infected through the blood stream and by direct extension. There are three points of special interest in con- nection with infection of these structures, viz. : (i) The production of jaundice ; (2) the formation of gallstones ; (3) the persistence of the microbe in the gall bladder after certain infections, especially the entericas, cholera, and microbic dysentery. Jaundice. — Pathology. — In jaundice produced by catarrhal inflammation the infection usually ascends from the duodenum and the infecting micro- organisms can be obtained from any source of infec- tion above and from the faeces. The mucous mem- brane of the bile duct is swollen and there is a plug of mucus in the ampulla of Vater. The ducts are distended with bile and the liver enlarged somewhat. Treatment, — When, as is usual, the microbes 95 Therapeutic Immunisation. involved are the ordinary catarrhal microbes, the most common, as we have seen, being M. catarrhalis and streptococci plus coliform baciUi, the initial dose should be 2| + 2| million, and the series 5 + 5, 7i + 7h + 15 + 15, 20 + 20. This method will be found to cut short these usually tedious cases in a most satisfactory manner. Gallstones. — Pathology. — Gallstones are, with few exceptions, caused by infection of the gall bladder with microbes of the typhoid-coU group. The chronic inflammation leads to increased excre- tion of cholesterin, mucinous material, and to stagnation of the bile. B, coli spreads up from the duodenum during chronic inflammation of it. Typhoid and para- typhoid bacilli lurk in the bile passages after they have disappeared elsewhere. The multiplication of the typhoid-coU group of microbes is favoured by bile. Prophylaxis consists in clearing up inflamma- tion of the duodenum by vaccines and treating typhoid and paratyphoid fever with vaccine. Treatment. — It is possible that gallstones, if they are not too large and if one is not impacted, might be got rid of by exhibition of oleic acid and by use of vaccine made from the patient's faecal microbes. If the stones have to be removed by surgical methods the bacteriology of the gall bladder should always be investigated and if microbes are present a vaccine used. Otherwise there can be no guarantee that more gallstones may not form. Enterica Carriers. — As just stated the gall bladder is a favourable environment for the 96 Alimentary Canal. growth and persistence of typhoid and paratyphoid bacilli, the microbes being excreted into the bowel and passing out with the faeces. Many epidemics have been produced by cooks, dairymaids, and others engaged in food preparation, who are carriers. In other of these cases the infection remains as a chronic pyelonephritis, the microbes being excreted in the urine. (See Typhoid Fever.) Prophylaxis and treatment has been discussed under typhoid fever. Appendicitis.- — While foreign bodies, such as faecal concretions, may act as predisposing causes by lowering the resistance of the appendicular tissues by direct injury of the cells or by interfering with the circulation, there can be no doubt that the lesions themselves are microbial in origin. Pathology, — The histological changes may be chiefly confined to the mucous membrane as in catarrhal appendicitis, where there is a mucopurulent exudate into the lumen of the organ and infiltration of the mucous membrane with leucocytes, or the inflamma- tion may involve all the tissues which are infiltrated with leucocytes and there is marked proliferation of the lymphoid cells. In these generalised cases the swollen appendix is covered with plastic lymph. In cases where there is a foreign body there is ulceration where this is in contact with the tissues. The ulcer frequently deepens, perforation occurs, and the foreign body is discharged into the peri- toneal cavity. In the worst cases the tissues are completely destroyed by the microbes and become gangrenous. In the last two cases there is either T.I. 7 Therapeutic Immunisation. general peritonitis or an abscess is formed by matting together of the intestines by plastic inflam- mation and the infection thus localised. Bacteriology. — In practically all cases B, coli can be isolated from the pus of an appendicular abscess, and unless the pus is carefully plated out the other microbes almost invariably present may not grow, as they are overwhelmed by the profuse growth of the B, coli. Sometimes this occurs in the body and the other microbes have disappeared when the culture is made. The microbes commonly found are streptococci and staphylococci. One or other of them is probably the primary infection and is carried to the appendix through the blood, or probably most commonly along the intestines. In most cases of appendicitis there is, as in other gastrointestinal infections, a source of infection above in the pos- terior nares tonsils or gums ; these microbes lower the resistance of the appendix and the Bacillus coli becomes pathogenic. In exceptional cases the pneumocor.cus, B. pyocyaneus, B. typhosus and paratyphosus have been isolated in pure culture. Treatment. — As in other infections of the gastro- intestinal tract and its adnexa, if the sources of infection were removed by means of immunisation with the causative microbes, the infection would, of course, not occur. Vaccines from these sources will permanently cure mild cases of appendicitis and remove the necessity, at present generally recog- nised, for operation during the quiescent period. In fulminating cases and in cases of abscess forma- tion immediate operation is necessary. Cultures 98 Alimentary Canal. should always be made at the time of operation and a vaccine prepared as soon as possible. In the usual case of B, coli and streptococci growing, the initial dose may be 2^ + 2j million of the mixed vaccine, and the series 3 + 5> 7i + 7h + lo, 15 + 15, and 20 + 20, etc., at appropriate intervals, according to the reaction. If staphylococci grow the initial dose is 25 million, and the series 25 + 2|, 50 + 5, 75 + 7h + 150 + 15, 200 + 20. The inoculations are best given on the upper part of the chest ; I + I of streptococci and B. coli is the best initial dose for a child and 10 + i if staphylococci are present. This procedure saves many lives and greatly reduces the period of convalescence. The Colon. — Since certain surgeons seem to think that the colon can be very well done without, it will not be out of place to give a brief description of the physiology of this part of the alimentary canal in man. Its functions are three in number : absorption of water and foodstuffs, excretion of waste products, preparation and lubrication of unused and unusable material for defaecation. The absorption by the large intestine is chiefly confined to water. According to Starling about 500 c.c. pass the ileocolic valve in twenty-four hours ; about 400 c.c. of these are absorbed in the colon, chiefly in the caecum, ascending, transverse and upper part of the descending colon. Of foodstuffs practi- cally only glucose is absorbed. The chief excretory function of the large intestine in man is the excretion of lime, magnesium, iron and phosphates. In man about 70 per cent, of the lime 99 Therapeutic Immunisation. and 50 per cent, of the magnesium leaving the body is contained in the faeces. Most of the iron excreted by the body is excreted in the fseces. Bismuth and mercury given medicinally are chiefly excreted by the colon. The chief secretion of the colon is mucus produced by the goblet cells of its tubular glands. It is important then to keep this excretory organ in good order. Infections. — The specific infections have been already dealt with. Most of the other inflammations are part of a general gastro-entero-colitis. There are two conditions, however, which call for special mention: they are (i) chronic constipation or, as it is called at present, intestinal stasis ; (2) mucous colitis. Whatever the primary cause of constipation, such as a diet containing too little indigestible material, for instance, cellulose or astringents, such as tannin in tea, or substances interfering with the neuro-mus- cular mechanism, or, chief of all causes, failure to go regularly to stool, there can be no doubt that when the resistance of the mucous membrane is lowered by [a) direct pressure of the faecal masses, and {b) by being poisoned by the reabsorption of excreted products, {c) infection from above, or as a sequel to a specific infection, the ordinary intestinal microbes become pathogenic and produce inflammation of the mucous membrane. So that in a case of intestinal stasis it will be found that there is evidence of this action both in the mucous membrane, which may be ulcerated in the pouches, in the musculature of the 100 Alimentary Canal. colon, and frequently evidence of chronic inflamma- tion in its peritoneal covering, e.g., formation of adhesions and membranes. In these cases, too, there is abnormal decomposition of foodstuffs by microbes, evidenced by constant production and passage of large quantities of foul-smelling gases. The general condition of the patient is poor. He, or more often she, appears pale, pasty and has foul breath. The patient is neurasthenic and easily tired. The symptoms are aggravated in the more intense degree of this condition known as mucous colitis ; sometimes there is diarrhoea in this disease, more often the patient suffers from chronic constipation. When the hard masses are passed there is a large excretion of mucous on their surface ; in the worst cases complete casts of portions of the colon come away. Treatment. — It will be frequently found, not only in cases of mucous colitis, but also in cases of ordinary constipation, that there is a source of infec- tion capable of infecting the gastrointestinal tract. The vaccine must then be made from the microbes isolated from this source as well as from the faeces or mucus passed with them. As in other cases, the faecal vaccine is made from the mixed aerobic growth on agar plates, and the initial dose, 2| million of each vaccine and the series 5 + 5, 7I + 71, 10 + 10, etc., a dose of 500 + 500 or more should be reached. It is well to empty completely the colon, if necessary, by washing it out thoroughly before the initial dose, otherwise a focal reaction in the colon may be very lOI Therapeutic Immunisation. painful. Of course the ordinary medicinal aids must be used. Liquid paraffin is a great stand-by, and it ought not to be forgotten that spleen extract stimulates both the musculature and the glands of the colon and pituitary extract the muscular coats. Seldom, indeed, in these cases ought it to be necessary to risk the patient's life by the dangerous operation of colectomy. Ischiorectal Abscess. — Vaccines made from the microbes isolated from the pus of ischiorectal abscesses, usually caused by a mixed infection, com- monly B, coli and staphylococci or streptococci, will rapidly bring about heaUng if used at once after opening. If the sinus is allowed to become chronic a very large dose may have to be attained before cure results. If the sinus opens into the rectum an operation to close this will be sometimes necessary, but this ought not to be done until the patient's resistance to the infecting microbes is raised, as it will then have a much better chance of success. 102 CHAPTER VII. RESPIRATORY SYSTEM. Diphtheria is caused by the B, diphthericB , which produces a superficial necrosis of the mucous membrane, usually starting in the upper respiratory tract, commonly on the tonsils, fauces or pharynx. The inflammation may spread up into the nose, down into the tracjiea and bronchi, more rarely down the oesophagus. Quite commonly it spreads over the uvula and soft palate, and may infect the skin, especially on the hands, if there is a superficial abrasion. The infection may be conveyed by the fingers to other mucous membranes, such as that of the vulva and vagina. Pathology, — The membrane consists of cellulo- fibrinous inflammatorj^ exudate, enmeshing the tissues which have undergone necrosis, the epithe- lium of the part having been previously cast off. Underneath it the blood-vessels and lymphatics are distended ; there is cellular and fibrinous exudate and the glands are blocked with exudate and desquamated cells. The B, diphtherice or Klebs- Loefifler bacillus is mostly confined to the superficial tissues, few of them getting into the circulation ; the general symptoms and the various paralyses which often supervene being due to the soluble toxins which this microbe produces. Bacteriology, — The bacillus is a highly pleomorphic, 103 Therapeutic Immunisation. Gram-positive, non-motile bacillus, varying in length from a cocco-bacillus to one 4 — 5 /x in length; it often stains unequally along its length, giving it a beaded appearance. When characteristic it is larger at one end than the other and slightly curved. On suitable media branching forms develop. Its morphology is determined largely by its environment. Loeffler's serum-glucose medium is best for producing the characteristic ' diphtheroid ' shape. This microbe is pleomorphic, and the true diph- theria bacillus is resembled by morphologically similar microbes, the only difference being in their capacity for producing the characteristic toxin. Con- sequently, the only absolute test is an immunity one. Equal doses of the suspected microbe are injected into two guinea-pigs, one of the animals being protected by a dose of antitoxic serum given at the same time. If the protected animal lives and the other dies, then the microbe dealt with is the diphtheria bacillus. For practical purposes, diphtheroid bacilli isolated from the throat of a patient suffering from mem- branous inflammation may be taken as true diph- theria bacilli. The crucial test is necessary for the diagnosis of diphtheria carriers, that is, apparently healthy persons who harbour diphtheroid bacilli in their throats, as frequently occurs during an epi- demic, and frequently after an attack of the disease. Immunity. — The body probably chiefly relies for its protection on antitoxin, which g,lso enables the diphtheria bacillus to be phagocyted. No doubt 104 Respiratory System. immune-body and heat-labile opsonin is also formed in small amounts, for, as we have seen, only a few bacilli seem to get into the circulation. Prophylaxis, — The common practice is to give 500 units of antitoxic serum to the members of a household or of a school in which a case of diphtheria occurs. This seems to me a doubtful practice, owing to the danger of producing anaphylaxis when serum is used should one of these patients develop the disease. A much better plan would be to use a vaccine for this purpose. A dose of 10 million for a child and 20 million for an adult may be used, or a small dose of toxin might be used. Treatment, — For the treatment of the disease at least 2,000 units should be at once given to a child and 4,000 to 8,000 units to an adult, and should be repeated until the membrane disappears. Serum rashes which may develop after an interval are rapidly got rid of by giving | to i c.c. of pituitrin. Should anaphylaxis develop the patient should be given at once to i c.c. of pituitrin, and the dose repeated at once if the symptoms return. The exhibition rapidly relieves the terrible bronchial spasm and other symptoms. If the bacilli are slow to disappear from the throat, as they frequently are, one or two doses of mixed autogenous vaccine made from microbes grown from the throat rapidly brings about their disappearance. A dose of 2\ million for a child and 5 million for an adult are average initial doses. The progression is 2|, 5, 7I, 10, 15, 20. As a rule the infection has cleared by the time the 10 million dose is reached. 105 Therapeutic Immunisation. Inflammations of Nasal Passages, their Acces- sory Sinuses, Larynx, Trachea and Bronchi. There are a great many different microbes infecting the respiratory passages. They produce catarrhal inflammation which varies from a shghtly increased production of mucus to ulceration and destruction of the underlying tissues. The openings of the sinuses may become closed, leading to the production of empyemata. In Acute and Chronic Catarrh of the Nose the sinuses probably always are involved. The infec- tions are important, as they interfere with respiration, frequently spread down into the bronchi, and swal- lowing of the microbes infects the gastrointestinal tract and the central nervous system through the ethmoidal plate. Pathology, — In acute infections the mucous mem- brane becomes swollen and cells of the epithelium become cast off ; an abnormal number of these cells turn into goblet cells and pour their mucus on the surface, which is mixed with a serous exudate and leucocytes. The blood-vessels beneath the epithelium are engorged and there is a serous and cellular exudate into the submucous tissues. Similar changes occur in the larynx, trachea and bronchi in acute infections. Most commonly such an infection begins in one part of the respiratory tract and spreads rapidly along the mucous membrane. In chronic infections there is a generalised cellular io6 Respiratory System. infiltration which leads to thickening of the mucosa. The goblet cells and glands continue to overact, so that there is a chronic mucous discharge containing a varying amount of desquamated cells and pus cells. In the nose this thickening is especially great over the inferior turbinals. Later, the sero-cellular exudate begins to contract owing to the formation of fibrous tissue, and an atrophic condition may result. In the nose this may result in atrophy of the bones. If the condition is due to the ozaena bacillus, the muco-pus and scabs produced by its drying have a characteristically foul odour. In the bronchi there is cellular infiltration of the whole wall, and the inflammation may spread to the peribronchial tissues, leading to peribronchial fibrosis. In places the wall of the bronchus may become so weakened that dilatation (bronchiectasis) takes place. Similar hypertrophy and atrophic changes occur in the larynx. Bacteriology, — Numerous microbes are capable of producing epidemics of colds as well as chronic in- fections. Very frequently the infection is mixed, the most common combination being the M, catarrhalis and streptococci, pneumococci, the B, influenzce, B, pertussis, staphylococci of various kinds. Fried- lander's pneumobacillus, Micrococcus meningitidis, the B. septus, diphtheroid bacilli, the ozaena bacillus. I have several times found a small non-motile Gram- negative bacillus resembling the influenza bacillus in appearance, but differing from it in its abundant growth on blood- agar. M. tetragegenus 107 Therapeutic Immunisation. and paratetragenus, B. pyocyaneus and B. coli occur sometimes, and the typhoid and paratyphoid A and B baciUi in the bronchitis that often occurs in these diseases. Staphylococcus. — Staphylococci are strongly Gram- positive spherical cocci about '9 in diameter. They grow rapidly in opaque, sharply-outlined colonies. They are classified into 5. aureus if the colonies are orange-yellow, 5. citreus if lemon-yellow, 5. albus if milky white. When spread on a slide they adhere in little clumps, so that they appear when stained somewhat like bunches of grapes. Hence the name. The three above all liquefy gelatine. On blood-agar some strains are lytic to the haemo- globin, others not. Pneumococcus, — The pneumococcus is a Gram- positive coccus about i /u. in length which usually grows in pairs (diplococcus) . Each coccus is, when typical, lanceolate in shape, and the thick ends of the cocci are approximated in the pairs. The cocci are frequently surrounded by a capsule of clear material which is not stained by Gram's method. They grow as small transparent, clear-cut colonies on blood-agar, not attaining a size greater than I mm. as a rule. When grown in broth they sometimes form short chains, so that it is difficult to distinguish them from streptococci, to which they are closely related. Pneumococci are said to be distinguished from streptococci by the fact that they ferment inulin and are soluble in bile-salt solutions. Four chief strains have been isolated for serum 108 Respiratory System. manufacture purposes. No doubt there are many more. Streptococcus, — Streptococci are Gram-positive, more or less spherical cocci which grow in longer or shorter chains. They vary in size from i ju, in diameter to sometimes a quarter of that size, and it is quite common in some strains to find the chain increasing in the size of its elements from one end to the other, so that at one end the cocci may be quite small, say "25 jit ; at the other they may be 2 /x. In some strains the elements of the chains tend to become elongated into bacillary forms. The colonies are small like those of the pneumo- coccus, but they look slightly less translucent. In some strains the colonies are very minute. Chain formation develops best in broth. Some strains develop a capsule. They vary enormously in toxicity. By passage through rabbits a strain has been so increased in virulence that, while at first it took the growth from several agar slopes to kill the animal, after several passages one microbe under the skin of a rabbit was certain death. There are niany Gram-negative cocci that infect the respiratory passages. The following are the most common in catarrhs : — Micrococcus, or Diplococcus Catarrhalis. — This microbe is on the average about i /x in diameter and usually occurs in pairs, the sides in apposition being flattened. It grows vigorously both at 37 deg. C. and at room temperature. The colonies attain a size of 2, 3 or 109 Therapeutic Immunisation. more millimetres in diameter, are heaped up, and usually have a yellowish tint. The colonies are firm though friable, but it is very hard to get the cocci separated from each other, as they adhere in masses. Another kind much less common is the Diplococcus pharyngis siccus, whose colonies are very tough and adhere to the surface of the medium. It actively ferments glucose, maltose, saccharose, and inulin. The Diplococcus mucosus has slimy colonies. There are other diplococci which produce pigment, such as the Micrococcus flavus. Micrococcus tetragenus is fairly common. This Gram-positive coccus commonly divides in two plains, so that groups of four arise, the elements of which are about i in diameter. The whole group is usually surrounded by a capsule. It grows on blood-agar as white colonies, large and tending to spread. The colonies are very tenacious and viscid owing to the gelatinous nature of the sheaths of the cocci. The M. paratetragcmts also sometimes occurs ; the individual elements of the tetrads are quite 3 or 4 /X in diameter. Pneumobacillus of Friedlander. — This Gram-nega- tive, frequently capsulated bacillus varies in size from coccobacillary forms to bacilli 4 or more microns in length. It is non-motile. It grows as white, shiny, viscous colonies on blood-agar. It actively ferments most of the sugars used in bac- teriological tests. It produces acid and gas in glucose, lactose, saccharose, mannite, dulcite, adonite, sorbite, inosite ; and produces acid in milk, but no Respiratory System. sometimes no clot. It does not liquefy gelatine. It is, in fact, closely related to the Bacillus coli group. Bacillus coli, — Members of the group are rare in sputum. They vary in size from coccobacilli to bacilli 10 /x in length ; the average size is 2 to 4 /x and about '5 /x broad. It is usually feebly motile. Gram-negative, and grows as large, dense, greyish-white colonies. It has characteristic fermentation reactions on sugars, producing acid and gas in glucose, lactose, mannite, dulcite, sorbite, and acid and clot in milk. It does not liquefy gelatine. Bacillus pyocyaneus. — Another uncommon para- site in the respiratory tract. B. pyocyaneus is a small Gram-negative motile bacillus 1*5 [jl to 3 /x in length and less than -5 [jl in thickness. On ordinary agar this microbe is easily identified by the development of a green pigment. Bacillus influenzce is a tiny Gram-negative non- motile bacillus, usually not exceeding 1*5 /x in length and '3 jtx in thickness, with rounded ends. It grows as minute transparent colonies on blood-agar. The Bacillus pertussis, — Bordet's whooping-cough bacillus is very similar to the influenza bacillus in morphology and growth. Fairly common in sputum as well as in pyor- rhoea alveolaris is a tiny Gram-negative bacillus morphologically like the influenza bacillus, but growing profusely on blood-agar. That it is patho- genic there can be no doubt, since the sputum of III Therapeutic Immunisation. patients reduced markedly on treatment with a vaccine of it, and focal reactions occurred. Other larger Gram-negative bacilli occur which need working out and description. Diphtheroid bacilli. — These microbes grow as small, clear colonies, and in morphology resemble the true diphtheria bacillus — some more and some less. Diphtheroids are quite common in tubercular sputum and catarrhal conditions, and often produce epi- demics of colds. There are, I think, many varieties which need working out and description. Most of these catarrh-producing microbes grow best on blood- agar plates . The specimen for examina- tion can be obtained by passing a platinum loop backwards through the anterior nares after thorough cleansing the atrium. It is better, however, to get the patient to aspirate the gobbet of sputum from the nose and expectorate it into a sterile bottle. This is washed, conveniently in a sterile tea- strainer, in order to get rid of mouth microbes. The centre of the piece of sputum is then spread on the blood-agar plate. A smear is made from the muco-pus and stained by Gram's method, to compare with the microbes that grow. If more than one microbe grows, as is usually the case, the microbes must be subcultured and a vaccine should be made from each. The ozaena bacillus grows well on blood-agar. Other catarrhal microbes are commonly present, notably staphylococci, so that a mixed vaccine is always necessary. 112 Respiratory System. Prophylaxis : Treatment. — There are two methods of ' catching cold ' : (i) The patient suffers from a chronic infection and gets acute exacerbations when his resistance is lowered by chills and other causes of lowering his resistance, or (2) both this class and those who do not suffer from chronic catarrhs get infected with virulent microbes from infected patients. The first class are in fact carriers, and their microbes become more virulent when their resistance is lowered or when they get into susceptible individuals. The chronic infections are, as a rule, sequels to the acute, and therefore prophy- laxis consists in either treating the acute catarrhs with vaccine or, at any rate, doing so if they do not completely clear up. It is not practicable to inoculate a healthy person against all the microbes that cause catarrh. In the case of whooping-cough epidemics, prophylactic inoculation is practicable and has given good results. All the contacts should receive doses ranging from 50 to 200 millions, according to age. It is remarkable how quickly an acute catarrh will clear up with an autogenous vaccine. The initial dose of most of the microbes is small. A dose of 2| million is a usual one for all except the staphylococci, when 25 million may be given ; the usual sequence is 2|, 5, 7I, 10, 15, 20, 30, 50, 75, 100, and so on; for staphylococci, 25, 50, 75, 100, 200, or more. These acute catarrhs usually clear up with a few injections. In chronic cases or when the acute is grafted on to the chronic it may be necessary to attain 500 — 1,000 million or more, or T.I. J 12 8 Therapeutic Immunisation. 2,000 — 5,000 million or more in the case of staphy- lococci. As in other cases, the upper limit of dosage must be judged for each individual. The initial dose may appear small, but one frequently gets focal and general reactions with it in chronic cases. The intervals are usually one or two days between the smaller doses, gradually increasing the period as the dose gets larger or if there is marked reaction. In acute cases it is quite possible to have a vaccine ready in twenty-four hours or less by omitting the usual tests and making sure of sterility by giving a rather longer heating than usual. In such emergency cases a vaccine made from the original plate may be used containing all the microbes that grow, pending the making of a more accurate vaccine from sub- cultures. In the early stages of whooping-cough a pure B. pertussis vaccine may be used, but later the infection becomes mixed, and therefore a mixed autogenous vaccine becomes necessary. The treatment of empyemata of the accessory sinuses is the same as for the nasal passages except that drainage must be produced by operation. Nasal obstruction produced by swollen turbinals is due, as we have seen, to infection, and local treat- ment by cautery is generally useless as it does not remove the cause and at best only gives temporary relief, and removal of the inferior turbinals is most harmful, often leading to ' dry nose.' Adenoids are the result of chronic inflamma- tion in the naso-pharynx. If the microbe or microbes that produce the condition are not dealt with by 114 Respiratory System. inoculation the adenoids frequently return after removal. The microbes are those that ordinarily produce catarrh. No inflammation of the respiratory tract should ever, nor need ever, become chronic. Asthma. — While there can be no doubt that there is a neurosis in this condition it is equally certain that the hypersensitiveness of the nasal mucous membrane is very frequently, if not always, pro- duced and kept up by infection of it by catarrh- producing microbes, since it is nearly constantly accompanied by chronic nasopharyngitis and bron- chitis. If the vicious circle is broken by over- coming the chronic infection the hypersensitiveness of the mucous membrane gradually subsides. Great care must be exercised in immunisation ; the initial dose must be half the usual one and the dose very gradually increased, since these cases are more liable to severe reactions then ordinary cases of bronchitis. Hay Fever. — In hay fever the attack is produced by the irritation of the nasal mucous membrane and conjunctivae by pollen or dust. The condition can frequently be cured by immunising the patient to the protein of various kinds of pollen. The pollen extract is made by grinding up the mixed pollen in normal saline containing 0*5 per cent, phenol. The initial dose is the extract of •0001 mg. of dry pollen, and the dose should be increased until one thousand times ('i mg.) this dose is attained. The intervals depend on reactions, generally 3 — 5 days. 115 Therapeutic Immunisation. Tonsillitis is an important condition, as the microbes causing it may produce inflammations of the intestinal tract and also invade the blood stream via the lymphatics and cause endocarditis, rheumatic fever, or the infection of other tissues. Bacteriology, — Many different microbes cause tonsillitis. Undoubtedly the most important are streptococci, which are the most common cause of rheumatic fever. Many others also cause it, e.g., staphylococci, pneumococci, M. catarrhalis. The Bacillus fusiformis is found in some cases of chronic follicular tonsillitis ; it is commonly found associated with other microbes, notably streptococci and staphylococci and spirilla. It is strictly anae- robic and grows best on glucose-agar. Pathology. — In acute tonsillitis the gland is en- larged and congested, there is hyperplasia of the lymphoid elements, and there is exudation of serum and cells into the tissues and sometimes on the surface. This exudate mixed with microbes may be most marked in the crypts, and the condition may go on to suppuration in the tonsil itself or behind it, producing a tonsillar abscess or quinsy. Treatment. — If the acute tonsillitis becomes chronic, or if repeated suppurations (quinsy) occur, the condition should always be treated by removal of the tonsil and a course of vaccine. This is especially important in children where tonsiUitis caused by streptococci is the common precursor of endocarditis and rheumatic fever. The initial dose depends on the microbes found : generally, 2| milhon of streptococci, 25 to 50 million 116 Respiratory System. of staphylococci. Five million will be quite large enough of B, fusiformis to start with. The series of doses are the same as those given in nasal infections {q.v,). Lungs. — Inflammation of the lung parenchyma may be produced by any or several of the catarrh- producing microbes already mentioned. In acute bronchitis affecting the smaller bronchi, lobules of the lung attached to inflamed bronchioles are con- stantly involved ; this condition is known as broncho-pneumonia. It is sometimes so extensive that the inflamed areas coalesce, so that the whole or part of a lobe may be involved. The most common cause of inflammation of the lung affecting the whole lung, a lobe or a large part of a lobe is the pneumococcus, either alone or combined with other of the catarrh- producing microbes. This lobar pneu- monia is really a septicaemia with focal manifesta- tions in the lung. It must not be forgotten that the lungs are one of the chief sites of the phagocy- tosis of microbes which are circulating in the blood. They can be infected via the respiratory passages and also by the lymphatic channels. Microbes of all sorts are found in healthy individuals in the mucous membrane down as far as the smaller bronchi, but not in the bronchioles or alveoli. Lobar Pneumonia is usually caused by the pneumococcus of Frankel, less commonly by the pneumobacillus of Friedlander. The infection may take place through the respira- tory passages or through the blood stream. The pneumococcus may be inhabiting the mouth or 117 Therapeutic Immunisation. upper respiratory passages, or the infection may come from without. The blood infection may come from pyorrhoea alveolaris or the tonsils. If the microbes are aspirated into the bronchi they may be carried by leucocytes into the lymphatic glands at the hilus. They may cause inflammation here of the glands draining a lobe or part of a lobe, obstructing the lymph flow from that area ; this leads to reversal of the lymph stream and the carrying outwards of the infection along the lymphatics of that area. These may reach the pleura, infect it and be carried inwards by the lymphatics of other areas. When the blood stream is first infected it is a little difficult to understand what determines the inflammation of a particular area of the lung. Probably a lowering of the resistance of that area, produced among other ways (i) through the nervous sj^stem by chilling of the skin over it or by injury ; (2) interference with its nutrition by previous interference with its lymph circulation by infection, for instance, with the tubercle bacillus ; (3) or it may be at the time being attacked by other microbes so that the infection is, as it commonly is, mixed. Pathology. — The alveolar capillaries become dis- tended and tortuous, the alveoli then become filled with plasma containing red corpuscles, leucocytes and alveolar cells which have desquamated from the alveolar walls or have become budded off ; the plasma clots, so that the cells are enmeshed in a fibrin network. Fibrino-cellular plugs block the alveolar and lymphatic capillaries, and there is a sero-cellular exudate into the interlobular connective 118 Respiratory System. tissue. There is always inflammation of the over- lying pleura, unless the pneumonia does not reach the surface, with a deposit of fibrin on it. There is acute inflammation of the bronchi of the part. The red cells are gradually phagocytosed by leucocytes and other cells, so that the lung looks grey instead of red. If the patient survives and recovery is normal the fibrin . blocking the alveoli and capil- laries becomes phagocytosed or digested by tryptic ferments ; the phagocytic cells which are effete undergo fatty degeneration and autolysis and the softened exudate is removed via the lymphatics, or comes away via the bronchi. If resolution does not take place the fibrino- cellular clot in the lung tissue may become organised, just as a blood clot does, fibrosis resulting. Or it may be invaded by other microbes, which may have been present from the first, for instance, the tubercle bacillus with subsequent caseation, or pyogenic microbes which may cause abscess or grangrene. The causative microbe can be isolated from the sputum, from the blood or from lung by puncture. The latter is a very rapid and effective way and appears to be perfectly safe. A syringe with i c.c. of sterile broth or normal saline and a long No. 7 needle attached is plunged into the solid lung, a little of the fluid is injected and aspirated back into the syringe and from it cultures are made. If the cultures are made from the sputum, mouth microbes should be first washed away from it with sterile water and the central part of the sputum used. To isolate from the blood 10 c.c. of blood should be 119 Therapeutic Immunisation. taken from a vein in the anticubital fossa and put in 100 c.c. of broth. At the same time some blood should be taken to add to the agar medium on which the microbe is to be grown. The material should be sown thickly on the plate so that a vaccine can be made from the first plate, as the vaccine must be available in as short a time as possible, subcultures being first made for diagnostic purposes so that pure vaccines can be made if more than one microbe grows. The pneumococcus can be distinguished from other members of the streptococcal group by its solution in bile salts and less certainly by its fermentation of inulin. Friedlander's pneumobacillus has quite charac- teristic sugar reactions. There are, of course, many strains of the pneumo- coccus. At the Rockefeller Institute pneumococci are divided into four groups. Antisera produced for any one group will not agglutinate a microbe from any other group nor, in vivo, neutralise their toxins. The toxin of the pneumococcus is an endotoxin, the microbe producing no soluble toxin in vitro. The filtered blood of animals dying of the infection and of patients before the crisis is toxic, so that in the body an exotoxin may be formed. Of course this toxicity of the blood may be due to lysis of the microbe with liberation of endotoxin. Before the crisis the amount of complement and the opsonic power of the patient's serum is low; both rise abruptly immediately before it. Small amounts of specific antibodies are formed. Immunity appears to depend practically entirely on efiicient phagocytosis. 120 Respiratory System. Prophylaxis, — If the patient has had a previous attack of pneumonia which has not been treated with vaccine his resistance to the microbe ought to be increased by a course of autogenous vaccine, as repeated attacks are common. Any focus of infec- tion, e.g,, post-nasal catarrh or pyorrhoea alveolaris, ought never to be allowed to continue. Treatment, — To judge of the results of any form of treatment in pneumonia requires very large figures, since the death rate varies so much with the virulence of the infecting microbe and the reactivity of the patient. Spontaneous recovery in a few days is quite common without any form of treatment. The mortality of the disease, however, is so very high that a great deal more than expectant treatment is desirable. Many polyvalent sera are obtainable and should always be used on the chance that the particular one used may contain antibodies appropriate for the strain infecting the patient. If it does not it is useless, but does no harm. The same considerations apply to stock vaccines. They must be polyvalent, and, since most com- mercial pneumococcic vaccines are of feeble potency a comparatively large dose, 25^ — 50 millions, must be given. Serum and vaccine should be given simultaneously so as to produce a mixed immunity. As soon as possible an autogenous vaccine must be available. The method of obtaining the specimen and the most suitable medium have already been referred to. Heating for fifteen minutes at 58 deg. C. is quite sufficient to kill the microbe. The initial 121 Therapeutic Immunisation. dose is 2j million and the sequence 2j, 5, 7J, 10, 15, 20. The rules laid down for the giving of vaccines in acute cases must be followed. I have no doubt that there is a great future for intravenous chemo- therapy in this and other acute infectious diseases. Especially is this so in pneumonia, where the focal lesion is in the lungs. I have not yet had an oppor- tunity of using the sodium salt of di-iodosalicylic acid in pneumonia, but its rapid effect in streptococcal infections, including those of the lungs, is such that 1 am very hopeful of its future in this disease; 2 to 5 c.c. of a I per cent, solution, according to age, is the dose indicated. It should be given every twenty-four hours. If possible the clotting of the blood in the capillaries and alveoli should be pre- vented. The best way we have of doing this is by giving sodium citrate i gramme (gr. xv.) every four hours. Ethylhydrocuprein has given very dis- appointing results. Broncho-pneumonia. — The etiology and treat- ment of broncho-pneumonia is the same as that of acute bronchitis and need not be considered separately. Pleurisy. — The pleura is always infected when the underlying lung is, and the cause is, of course, the same, viz., the various catarrh-producing microbes. By far the most common cause of pleurisy with effusion is the tubercle bacillus. Pathology, — When infected the pleura becomes hyperaemic and there is an increased exudation of lymph from the capillaries ; this lymph contains more fibrin than normally. The surface becomes 122 Respiratory System. roughened owing to the endotheKal cells becoming cuboidal and budding off or desquamating, fibrin becoming deposited on the surface. The stomata become plugged with fibrin. If, then, there is a con- tinued exudation of lymph it cannot escape and an effusion results. If the causative microbes attract large numbers of leucocytes and kill them an empyema results. The fibrinous deposit frequently becomes organised and adhesions result. If the toxin of the microbe produces lysis of the endothelial cells of the capillaries the effusion is haemorrhagic. Diagnosis, — When the pleurisy is connected with lung lesion or occurs in the course of an acute catarrh the cause may be presumed to be that of the lung lesion. Pleurisy with effusion is most commonly tuber- cular, but sometimes it is not, so that it is always well to make an ordinary bacteriological examina- tion. The fluid should be drawn off into a sterile vessel and allowed to clot ; the clot is removed and digested with liquor pancreaticus, centrifuged, and cultures made from the deposit, which should also be stained for tubercle bacilli. If no microbes grow and no tubercle bacilli are seen the patient should certainly be tested for tuberculosis by subcutaneous injections of tuber- culin (see p. 215). When there is an empyema there is no difficulty, as a rule, in isolating the microbe from the pus. The most common causes are pneumococci, streptococci, or staphylococci; but any microbe almost can produce it, for instance, B, coli, B. typhosus, or 123 Therapeutic Immunisation. the paratyphoids. In the entericas, however, the empyema is often not caused by the primary infec- tion, but by other microbes. Treatment, — When the pleurisy is connected with a lung lesion the treatment is that of the lung lesion. Sometimes dry pleurisy occurs with no obvious lung lesion in rheumatic conditions. There is then a focus of infection somewhere as in the gums, from which the causative microbe, usually but not always streptococci, can be procured. If microbes other than the tubercle bacillus are found in a pleurisy with effusion, vaccines are made from them and an ascending series of doses given. A very useful adjuvant treatment is to inject 5 to 10 c.c. of the effused fluid, taken from the chest, underneath the skin every few days. An empyema (non-tubercular) must be drained as soon as possible and an ascending series of doses of a vaccine from the causative microbe given. The initial dose is 2| million for all microbes except the staphylococcus, where it is 25 million, the series is 2|, 5, 7J, 10, 15, 20, etc., up to at least 500, while in the case of staphylococci it is 25, 50, 100, 150, 200, and so on, up to at least 2,000. 124 CHAPTER VIII. URINO-GENITAL SYSTEM. Nephritis. — Except in the case of acute pyogenic infections the cause of inflammations of the kidneys which do not produce pus in the urine (acute and chronic Bright 's disease) is not properly understood ; indeed, as far as I know, httle or no attempt has been made to investigate them bacteriologically. The kidneys may be infected through the blood stream, probably much the most common way, or they may be infected by pyogenic organisms ascending along the ureter. In either case the pelvis of the kidney may be involved as well, a pyelo- nephritis resulting. Acute and Sub-acute Non-suppurative Nephritis (Bright's Disease). — In most fevers the kidneys are more or less affected. This is not surprising since excretion of microbes by the kidneys is one of the chief methods of getting rid of microbes in the circulation. In scarlet fever the kidneys are commonly in- fected by way of the blood stream, the cause probably always being streptococci. I have seen many cases of a similar kind associated with acute tonsillitis. They also may become infected as a sequel to pneumonia and similar infections. So also 125 Therapeutic Immunisation. in the typhoid and the paratyphoid infections the kidneys may become acutely infected. I have made bacteriological investigation of a few cases of sub-acute nephritis in soldiers and found various microbes (see p. 130). These microbes were found on several examinations ; both focal and general reactions occurred on giving the patient vaccines made from them ; and in most cases the albumen entirely disappeared from the urine or was reduced to a trace. I have little doubt that I was using the causative organisms. No causative organism has been isolated from acute trench nephritis. Amte suppurative nephritis occurs in the course of pyaemias and septicaemias with pyogenic microbes and as an extension of a suppurative pyelitis. Chronic nephritis may be a sequel to the acute condition, or may come on so sub-acutely as to be chronic from the beginning. As I have said, their origin is quite obscure. I have little doubt that many of them will be found to be microbial in origin, for the more one examines bacteriologically the urine of patients suffering from chronic rheu- matism and such conditions, the more one realises the number of people who are excreting microbes in their urine without any trace of pus cells or albumen in the urine. It seems to me improbable that the kidneys in a certain number of such cases will not become affected sooner or later, especially as their resistance may be lowered by excretion of products of abnormal metabolism (see p. 154), which they may have to excrete. These abnormal 126 Urino-Genital System. metabolic substances may act on the blood-vessels primarily and, by affecting the nutrition of the cells, bring about their degeneration. As I have already stated, it is not difficult to find sources of chronic septicaemia, chronic pyorrhoea alveolaris, tonsillitis and gastroenteritis being common sources. The whole subject needs careful and prolonged bacteriological and other investigations. Pathology. — The cellular changes depend on whether the glomeruli, tubules, interstitial tissue or blood-vessels are primarily affected, the viru- lence of the causative microbe, and whether it is pyogenic or not. In acute scarlet fever nephritis the first changes appear in the glomeruli, the endothelial cells of the capillaries of the tuft are affected and red blood corpuscles escape into the glomerular space. The endothelial cells of the capillaries become swollen and cuboidal, and a similar change of these cells in the arterioles leads to narrowing of their lumen ; these endothelial cells of the arterioles proliferate, and there is proliferation of the cells of the glome- rular capsule. The walls of the arterioles and of the glomeruli become invaded with leucocytes. The result of these changes is that the circulation in the glomeruli ceases and there is no excretion by the glomeruli, consequently the tubules normally flushed by the fluid secreted by the glomeruli are not flushed. Partly owing to this and partly owing to the action of the toxin, cloudy swelling, degenera- tion, desquamation, and even necrosis of the cells of th^ tubules result. The interstitial tissue also 127 Therapeutic Immunisation. becomes more or less affected. As a rule, all the glomeruli are not affected. If they are, complete or nearly complete suppression of urine results. In acute parenchymatous nephritis the onus falls on the tubules, the cells of which undergo cloudy swelling and proliferation or, if the toxin is powerful, necrosis. Desquamation follows, and the tubule becomes filled with degenerating or degenerated cells, cell debris, fibrin and blood cells. The changes in the glomeruli are slighter, but there is usually oedema or congestion of the interstitial tissue. In acute interstitial nephritis the first changes are in the interstitial tissue. There is infiltration of this tissue with lymphocytes, polynuclear leuco- cytes and plasma cells, especially between the tubules of the cortex and round the stellate and interlobular veins. From the acute stage, if the patient survives, the condition either completely clears up or passes through a sub-acute to the chronic stage. Fibrous tissue forms, which contracts and leads to various appearances according to its extent and position. Abscess is either produced by a septic embolus in pyaemia or by an ascending infection from the renal pelvis. In pyaemia the embolus lodges in the inter- lobular arteries, arterioles or capillaries, and abscesses form round them. The microbes later infect the tubules through which some of them are being excreted, and the pelvis of the kidney as a rule becomes infected. If the primary infection is in the pelvis the inflammation spreads up along the col- 128 Urino-Genital System. lecting tubules, elongated abscesses being formed. In both conditions the whole kidney is more or less affected, the interstitial tissue showing oedema, congestion and infiltration with inflammatory cells. Further, if the patient survives, the inflammation may spread to the surrounding tissues and a perinephritic abscess result ; pyelitis and ureteritis may result either from infection from above, due to microbes excreted from the kidney or from below by infections ascending from the bladder. They are often complicated or originated by the presence of a calculus. Bacteriology. — The diagnosis of the kind of infec- tion and the settling of the question as to whether one or both kidneys are affected require some care, since in one-sided cases the symptoms may be referred to the opposite side to the one affected. Cystoscopy and catheterisation of the ureters must be resorted to in such cases. Great care must be taken in taking the specimens for bacteriological investigation. In the male, either a catheter can be used, or the specimen may be passed directly into a sterile vessel, the whole glans penis being thoroughly disinfected first. The first half ounce of urine passed should be rejected. In the female, a catheter must be used and the external genitaUa and the meatus most carefully cleansed and disinfected before passing it. Thorough douching in a proper gynecological chair is desirable. The diagnosis should be checked by several examinations. In the later stages of chronic neph- ritis it is improbable, in most cases, that the original T.I. 129 9 Therapeutic Immunisation. causative organism will be present so that it is of the utmost importance to examine these cases in the early stages. There is, as a rule, no difficulty in identifying the causative microbe or microbes. The acute glomerular nephritis which occurs in scarlet fever and after acute sore throats is probably alwaj^s caused by streptococci. Some cases of acute and sub-acute parenchymatous nephritis I investi- gated were caused by Staphylococcus aureus (one case), Staphylococcus albus (two cases). Gram-posi- tive bacilli (two cases) ; a Gram-negative bacillus, non-motile, producing acid in litmus milk but not affecting the ordinary sugar media nor producing liquefaction of gelatine. The acute descending pyelonephritis is usually staphylococcal, strepto- coccal or produced by members of the typhoid-coli group. Quite commonly B, coli is associated with the typhoid or one of the paratyphoids in post- typhoidal inflammation, while B, coli and staphy- lococci may be associated. In ascending inflammation the infection is most commonly produced by the B. coli, very rarely by gonococci. Prophylaxis and Treatment. — The treatment of scarlet fever and acute streptococcal infections of throats by immediate use of antisera and the inocula- tion of an autogenous vaccine as soon as possible will certainly reduce the number of cases of acute nephritis. Failing these the exhibition of sali- cylates is certainly better than nothing. If localised infections, such as pyorrhoea alveo- laris, tonsillitis and gastroenteritis, are the source of 130 Urino-Genital System. infection in some of the cases of acute and chronic nephritis, prophylaxis consists in clearing up these infections with vaccines before chronic septicsemia occurs. The prophylaxis of ascending infections consists in treating the infection of the lower urinary passages with vaccines so as to prevent the spreading of the infection. Acute streptococcal nephritis should be treated by the immediate injection of efficient polyvalent antistreptococcal serum, pending the isolation of the causative microbe from the urine and the making of the vaccine. The doses should be 2|-, 5, 7I, 10, 15, 20 million, and larger if necessary, the intervals depending on reactions. The initial doses and series of all other causative microbes are the same except in the case of staphylococci, when the doses are ten times larger, viz., 25, 50, 75, 100, 150, 200, and so on. As in other cases the more chronic the condition the larger the dose that will have to be attained. When the infection is a double one, as it quite commonly is — for instance, when B. coli is associated with the typhoid or paratyphoid bacilli — then the initial dose is 2| + and the series as before, or if staphylococci and one of the others 25 + 2|. Such were the doses I used with the Gram-positive and Gram-negative bacilli mentioned above. These microbes were isolated several times from care- fully collected specimens, and vaccines of them produced general and focal reactions in the patients. After the second dose (5 miUion) in one of the cases excreting the Gram-negative bacillus, the albumen 131 9-2 Therapeutic Immunisation. entirely disappeared from the urine. In chronic cases very high doses may have to be reached ; the final dose in a case of double acute pyelonephritis caused by the B. coli was i,ooo million. In ascending pyelonephritis with abscess and in cases of perirenal abscess the pus must be evacuated through the loin, and in calculus pyelonephritis or pyelitis the stone must be removed. Vaccines will help the surgeon to save many kidneys which otherwise would have to be removed. The urine must always be kept neutral, when acid, by the exhibition sodium citrate, i gramme (15 grains) three or four times a day is usually about right. Cystitis is caused by infection coming either by way of the ureters or urethra, so that it may occur during urethritis, prostatitis or pyelonephritis. It is a very common occurrence during ' catheter life ' where decomposition of residual urine is a potent predisposing cause. By far the most common cause is B. coli, but many other microbes occur, typhoid and the paratyphoids A and B, staphylococci, streptococci, gonococci, and various microbes producing decom- position of urine. Pathology. — In acute catarrhal cystitis the mucous membrane is congested with red points, due to congested vessels and haemorrhages ; the epithelium is swollen and desquamating. The mucous mem- brane is infiltrated with leucocytes which make their way to the surface and into the urine. In chronic catarrhal cystitis the bladder wall becomes thickened, owing to infiltration of the submucous 132 Urino-Genital System. coat as well, with inflammatory cells, while, if there is obstruction to the outflow of urine there is hyper- trophy of the muscular walls with increase of fibrous tissue between the muscle bundles. If the inflammation is very intense it may lead to superficial necrosis forming a necrotic membrane. This may be localised and cast off, an ulcer resulting. In very severe cases the inflammation may spread to the surrounding tissues. Treatment. — Acute cystitis yields very rapidly to vaccines. In chronic cystitis it is necessary to work up to a very big dose, as a rule ; this is not surprising, considering the anatomical changes just described. If the prostate is enlarged it is much better to have it removed. The dosage of vaccine is the same as for other parts of the urino- genital system. The initial dose of staphylococcus may be loo million unless the kidneys are involved, when it must be 25 million, B. coli 2| million, streptococci 2\ million, typhoid and paratyphoids 2| million, gonococcus 2-| million. In acute cystitis, when a dose of 500 million staphylococci and 100 million of the other microbes is reached the patient is usually well. As already mentioned, in chronic cystitis very large doses may have to be reached. In these cases lavage with hypertonic saline solution is very useful. As in other conditions a stitch in time saves nine; bladder infections ought not to be allowed to become chronic. If the urine is acid it must be kept neutral with citrate of soda. 133 Therapeutic Immunisation. Urethritis in Male. — Urethritis in the male is, for all practical purposes, the result of infection from a vagina infected with the gonococcus. Cases occasionally occur in which the original infection is some other microbe, but as a rule the male urethra seems able to resist infection by other microbes until its resistance is lowered by infection with the gonococcus. Pathology. — The inflammation may be confined to the anterior urethra or may spread back to the posterior urethra and infect the prostate, vesiculae seminales, epididymis and testis. It rarely spreads to the bladder. It may get into the circulation through an ulcer and produce gonorrhoeal rheumatism or endocarditis and septicaemia. The pathological changes in the urethra are those of inflammation, viz., hyperaemia, infiltration with leucocytes and pus formation. Ulceration pro- duced by sloughing of the mucous membrane is common. The changes in the prostate may amount to simple catarrh of the tubules with desquamation of their cells and infiltration with leucocytes. As a rule the inflammation spreads to the interstitial tissues, which become infiltrated with inflammatory cells. The prostate on examination may be uniformly enlarged and boggy if the inflammation is catarrhal, but if the interstitial tissue is infected the whole gland, one lobe or parts of lobes are hard and nodular and very tender. These conditions if not suitably treated may last for months or many years. Areas may break down 134 Urino-Genital System. to form abscesses which may be so extensive as to involve the whole gland. The tubules of the epididymis and testis show catarrhal changes and are invaded with leucocytes. The tubules may dilate and form abscesses, the interstitial tissue being involved and the abscesses may burst on the surface. More frequently under suitable treatment resolution occurs. The tunica vaginalis is always involved in epididymitis and usually in orchitis. Bacteriology. — The diagnosis of gonorrhoea is not difficult in the acute stages. Smears of the purulent discharge from the urethra show Gram-negative diplococci ingested in leucocytes and desquamated epithelial cells. Such appearances are for all practical purposes diagnostic. Cultures must be made. The gonococcus is a very delicate micro-organism and requires special culture medium, which must be warmed to body tempera- ture before insemination ; + 6 agar with i c.c. of human blood to every lo c.c. of agar grows the microbe excellently. The agar must be accurately + 6 ; must be made with fresh meat extract, and must not have been heated to more than lOO deg. C. in its preparation. On this colonies of the gono- coccus grow to as much as i mm. in diameter at the end of twenty-four hours. They are slightly milky in appearance and have a clean-cut contour. The colonies increase in size for several days until they are several millimetres or more in diameter with a characteristic irregular outline. They should be subcultured not later than three or four days, 135 Therapeutic Immunisation. as the microbes in the primary culture die out, as a rule, towards the end of a week. For making the blood agar the patient's own blood may be conveniently used. It is taken with a syringe from one of the veins in the anticubital fossa, the agar being melted and cooled down to 50 deg. C. before adding the blood ; one plate and several slopes for subculture should be made for each patient. The gonococcus is a Gram-negative diplococcus with the contiguous sides slightly hollowed out, so that each element is somewhat kidney shaped. It keeps its shape fairly well on subculture if the medium is suitable {e.g., if there is sufficient blood present). After several subcultures, as a rule, pleomorphism occurs, small and large round cocci appearing and the diplococcal form disappearing. If the urethritis becomes chronic and spreads up to the posterior urethra other microbes constantly invade it and take part in and continue the condition, while the gonococcus frequently entirely disappears from the smears. There may be one or more of these secondary invaders. The most common are haemo- ly tic and non-haemolytic staphylococci ; diphtheroids, of these there are two chief kinds, one forming very large pinkish, clear cut, round colonies on blood agar, the other small translucent or very shghtly opaque colonies like those of the diphtheria bacillus ; streptococci and Gram-negative bacilli of several kinds. Some of the latter give the sugar reactions of coliform bacilli; others do not affect the ordinary sugars at all, and are not motile. The Gram-negative bacilli infecting the urethra need working out. 136 Urino-Genital System. To take cultures the end of the penis must be disinfected with ether, the patient then opens the meatus by puUing the hps sideways on each side and the loopful of pus is removed. If the prostate is involved it must be massaged first through the rectum so as to get a fresh discharge. The toxin of the gonococcus is an endotoxin, and it is probable that spontaneous recovery is due to the development of sufficient specific antibodies to enable the phagocytic cells to digest the microbes they so readily ingest, for, during the acute stages, the ingested microbes do not appear to be in the least affected by the ferments of the leucocyte. Inoculation with efficient antigen brings this condi- tion about, as a rule, with certainty and rapidity. Prophylaxis. — The best prophylactic measure is the abstention from illicit sexual intercourse, a counsel of perfection which will never be attained as long as the sexual instinct is one of the most powerful forces in nature. Failing abstention, washing the penis with an efficient antiseptic, such as 3 per cent, carbolic solution, will probably prevent infection in the majority of cases, if applied at once after copulation. Treatment, — I am afraid ' an attack of the clap ' is frequently not at all regarded seriously enough. The consequences of neglect of efficient treatment are so serious that it is quite worth while to take the trouble of making an autogenous vaccine. Acute Stages. — Pending the production of an autogenous vaccine the patient should be given a dose of stock vaccine which should be made, if 137 Therapeutic Immunisation. possible, from the strain prevalent in the neighbour- hood from which the patient got the infection or, at any rate, be made from many strains. Much of the vaccine to be obtained commercially is quite useless. The microbe from which the stock vaccine is made must be grown on fresh human blood. If the antigen is efficient a dose of 2j million is quite large enough to start with, and the progression 5, 10, 20, is suitable. The first dose of the auto- genous vaccine is the next dose of the series begun with the stock vaccine. The series continues 40, 80, 120, 200, and so on, if necessary. The intervals depend on reactions. The urethra of the patient should be kept flushed out by making him drink plenty of water, and his urine should be kept amphoteric by giving him citrate of soda, i gramme (15 grains) four times a day is usually sufficient. If on culture another or other microbes grow, they must be included in the vaccine. I do not believe in douching. I think it is in most hands liable to spread the infection backwards. I know a large number of cases of acute gonor- rhoea get well of themselves or by ordinary methods, but I see too many chronic cases to think these methods very efficient. Chronic Cases, — Still more inefficient is the ordi- nary treatment of gleet or prostatis. Posterior urethral douches to kill microbes deep in the tissue of the prostate are, to my mind, ridiculous. Perhaps the most common combination of microbes in these conditions is staphylococci and diphtheroids ; the other microbes already mentioned 138 Urino-Genital System. are also quite common. The gonococci have fre- quently disappeared, but an efficient gonococcus vaccine must always be included in the mixed vaccine used, as this microbe may be still lurking deep in the tissues and not appear in the discharge. The initial dose of the staphylococcus vaccine is 25 million, of all the others million. So that if staphylococci and diphtheroids grow the doses would be 25 million staphylococci, 2-| million diphtheroids, and 2J million gonococci, and the ascending series : — 50+5+5 100 + 10 + 10 200 + 15 + 15 400 + 20 + 20 600 + 40 + 40 800 + 80 + 80 1,000 + 120 + 120 2,000 + 200 + 200, and so on, if necessary. The intervals depend entirely on the presence or absence of reactions. As a rule, one or two clear days between the earlier doses, increasing to a week between the larger are suitable intervals. As before, the urine must bekeptamphotericwithsodium citrate. It is essential periodically and methodically to massage the prostate, if enlarged, through the rectum. Female Genital Organs. Gonorrhea. — The gonococcus infects the vulva, first producing swelling, oedema and ulceration of the labia, urethritis, inflammation of the vaginal glands, 139 Therapeutic Immunisation. including the ducts and glands of Bartholini ; the vaginal wall is, as a rule, not so much affected. The infection, if not checked, spreads up the cervix and uterus to the tubes, producing pyosalpinx and sterility. Adhesions of the fimbriated end to the ovary may occur with abscess formation in the latter. As in the male, when the inflammation becomes chronic the gonococci may disappear and other microbes continue the condition. These are much the same as those in the male. That the gono- coccus may lurk deep in the tissues is shown by the fact that sometimes the gonococcus may be isolated during or just after menstruation, but not during the intervals. The principles of treatment are identical with those described for the male. It is a question worth considering, whether prophylactic inoculation of prostitutes might not reduce the case incidence. Other cases of vaginitis occur caused by other micro-organisms, the flora being very various. The infection is usually a mixed one, and some of the causative microbes I have found were not referrable to any described group. Acute Endometritis occurs during the puer- perium, the infection being introduced by hands or instruments or is due to spread of infection from a preceding vaginitis. Pathology. — Septic infection occurs chiefly at the placental site where there are areas of necrosis ; the rest of the endometrium is acutely inflamed. Septic thrombosis occurs in the veins, and the 140 Urino-Genital System. lymphatics become infected and form large swellings with smooth inner walls filled with pus (Shennan). Puerperal fever is always a septicaemia or pyaemia. I have no belief in sapraemia as a probable clinical entity. Pyaemia is due to detachment of pieces of septic clot in the veins. The infection frequently spreads to the pelvic cellular tissues, and not infrequently to the peritoneum. Bacteriology, — Streptococci, staphylococci, and Bacillus coli are much the most common causes. Quite commonly the infection is mixed, staphy- lococci and streptoccoci, or either of them with the 5. coli. Much less commonly other microbes, such as Micrococcus catarrhalis are the cause. Blood cultures and cultures from the interior of the uterus must be made at once before any douch- ing, except a vaginal douche with sterilised water or normal saline. An antiseptic intrauterine douche before making a culture may take away a patient's one chance of survival. Cultures should be made on a blood agar, a McConkey plate (or a plate of other differential medium) and in broth. The blood culture in broth should be kept shaken occasionally during the first quarter of an hour or contain a little liquor pan- creaticus to prevent the blood clotting (Douglas). Subcultures may be made in twelve hours. Smears stained by Gram's method may give one an idea what the causative infection is, but it is frequently impossible in smears to differentiate between staphylococci and short-chained streptococci. One blood-agar plate should be plentifully inseminated 141 Therapeutic Immunisation. with the pus so that sufficient growth may be present in twelve hours to make a vaccine if it is a pure culture. Prophylaxis is, as a rule, outside the sphere of vaccine therapy. If, however, the patient has a history of infection, after one or more previous con- finements, or has an obvious mucopurulent discharge, a bacteriological investigation of the cervix should be made and a course of vaccine given. Treatment. — At once, besides the usual focal treat- ment, a dose of stock vaccine, containing the three commonest causes, should be given, viz., 25 million staphylococci, 2-| million each of streptococci and Bacillus coli. If the smear shows cocci the vaccine may be usefully accompanied by 25 c.c. antistrepto- coccus serum. As soon as possible an autogenous vaccine should be prepared. This can often be ready within eighteen hours. The initial doses are 25 million for staphylococci, 2| million for B. coli and streptococci and for most of the other microbes which may be exceptionally isolated. The series is for staphylococci 25, 50, 75, 100, 150, 200 million, for the others 2|, 5, 7I, 10, 15, 20. It is always well to give several increasing doses after the temperature has permanently subsided to guard against chronic endometritis. The intervals are judged according to the rules laid down for acute infection (see p. 62). Acidosis must be guarded against by giving sodium citrate, 15 — 20 grains every four hours. In very severe infections intravenous anti- septics may be very helpful. Iodine preparations may be used first, iodoform in ether, 66 mg. (i grain) 142 Urino-Genital System. in I c.c. pure ether given intravenously daily, or di-iodosalicjdic acid, 3 — 5 c.c. of a i per cent, solution of the sodium salt given intravenously daily. If these do not appear to be working, chlorine preparations may be tried, such as chlora- mine T or Eusol. I have had some very promising results with di-iodosalicylic acid in septicaemias, except in the typhoid and paratyphoids. Extract of the posterior lobe of the pituitary gland should be given so as to keep the uterus contracted and so help to expel septic material and lessen the area and channels of septic absorption. Chronic Infections. — Chronic endometritis with a white discharge is one of the most common causes of ill-health in women and, in many cases, one of the most obstinate to cure by ordinary methods. There can be little doubt that the chronic irritation pro- duced by microbes is the most common cause of cancer of the uterus in women, when the environ- ment for its development is suitable. Pathology, — The mucous membrane becomes thickened, oedematous and vascular, and there is a great increase in the size or number of the glands, which may grow on to the vaginal aspect of the cervix, producing ' erosions.' Later the glands may atrophy. Continued hypertrophy of the mucous membrane in a particular situation leads to the formation of a polypus. In some cases there is infiltration with leucocytes. Although the bacteri- ology of these cases has not been worked out on a large scale, yet in the cases I have investigated I have always found a microbial cause. The most 143 Therapeutic Immunisation. common infections are staphylococci or Bacillus coli. In a case of membranous endometritis I isolated Micrococcus tetragenus in pure culture; in another case the condition was due to a mixed infection with Bacillus coli and diphtheroid bacilli. This patient suffered from a most irritating herpetic irruption of the vulva, the irruption spreading even up to the mons. From the blebs the diphtheroid bacilli were isolated in pure culture. One case with an irritating vaginal discharge had been operated on three times for recurrent epithelioma of the vulva. Coliform bacilli were isolated from the discharge ; the discharge cleared up with a full course of vaccine. There has been no re- currence, so far, of the epithelioma (over three years). To obtain cultures, after thorough douching of the vagina with sterile water a speculum is passed, the uterus pulled down with a bullet forceps and the platinum loop passed up into the interior of the uterus. Cultures are made on agar or blood-agar slopes or plates. Treatment. — As in other chronic conditions a large dose will generally have to be attained before a permanent effect is obtained. The initial dose of staphylococcus vaccine is lOO million and of the others 2-| million. It is usually necessary to attain a dose of 4,000 million in the case of staphylococcus infection and a dose of 500 — 1,000 miUion in other infections. As in all cases in women it is inadvisable to give a dose for the two days before and the first two days of menstruation. Adjuvant Treatment. — Testicular substance, 10 144 Urino-Genital System. grains three times a day, will be found to tone up the uterus and reduce menorrhagia. In some cases a curetting of the hypertrophied mucous membrane will hurry matters up. Fallopian Tubes and Ovaries. — These are so inaccessible that they cannot be examined direct. Generally, the cause of salpingitis is the same as that of endometritis. In acute pus tubes and abscess of the ovary the immunisator may be able to help the surgeon to do conservative surgery with increased prospect of success. The successful reproductive results in some cases produced by a small piecj of ovary attached near the opening of the stump ol an amputated Fallopian tube are most remarkable. Successful early inoculation of gonorrhoeal infec- tion in the female ought to prevent such cases occurring. 145 10 CHAPTER IX. BONES, JOINTS, WOUNDS. Acute Osteomyelitis. — The initial symptoms are constantly mistaken for those of acute rheu- matism, from which conditions the diagnosis at first may be very difficult if the site of the infection is near a joint. Pathology. — The inflammation may start either in the periosteum, medulla, or both, and may occur in the diaphysis or epiphysis; a sKght injury usually determines the site. Pus forms in the marrow and under the periosteum, and this is followed by osteitis and necrosis of the bone itself. The inflammation spreads to overlying tissues and may work through the cartilage into joints. If the patient does not die of pj^aemia the disease becomes chronic and new bone is laid down by the periosteum, the dead bone inside forming a sequestrum lying in an abscess cavity. In cancellous bone if the suppuration becomes chronic, an abscess is present surrounded by dense bone. Bacteriology, — The causative microbe is isolated from the pus after incision of the periosteum and, if necessary, trephining. The most common microbes are Staphylococcus aureus, albus or citreus, or streptococci. Prophylaxis, — The patient must have been suffer- ing from a chronic septicaemia with the microbe found. It becomes more virulent on growth in the tissues 146 Bones, Joints, Wounds. whose resistance have been lowered by injury or other causes. The source of these microbes is some badly locahsed infection, such as pyorrhoea alveo- laris, tonsiUitis or gastroenteritis. As in other cases, prophylaxis consists in clearing up such infections with appropriate vaccines and local treatment. Treatment, — The surgical treatment must be prompt and energetic, free incision and trephining of the patient's limb, if life is to be saved. As soon as possible a vaccine should be prepared. It is usually possible to have it ready in fourteen to eighteen hours. Cultures should be made on agar or blood-agar and in broth — in the latter to dis- tinguish, as soon as possible, between staphylococci and streptococci. The initial dose of staphylococcus vaccine is 25 million, and the progression 25, 50, 75, 100, 150, 200, and so on. In chronic cases, in which there is often chronic pyaemia or septicaemia with multiple abscesses, very high doses may have to be attained. In one case due to Staphylococcus albus I attained a dose of 30,000 million before the patient remained permanently well. The initial dose of streptococcus vaccine is 2j million, and the progression 2J, 5, 7I, 10, 15, 20, 30, 50, 75, 100 million, and so on. The intervals depend on presence or absence of reactions. Of course, sequestra must be removed as soon as they become loose. Acute Suppurative Arthritis occurs in pyaemia and septicaemia or is the result of spread of infection from neighbouring bones. Pathology. — The synovial membrane becomes infil- 147 Therapeutic Immunisation. trated with inflammatory exudate and cells, the lining cells desquamate, and there is increased secretion of synovial fluid which becomes purulent. If suitable treatment is not used, or is unsuccessful, and the patient lives, the membrane becomes con- verted into a layer of granulation tissue. The articular cartilages become vascularised, infiltrated and, finally, eroded, so that the end of the bone is left bare. The underlying bone undergoes a rare- fying osteitis and necrosis. The capsule and liga- ments are infiltrated and softened, so that spon- taneous dislocation may occur. Bacteriology and Treatment, — At once in acute synovitis not due to injury the joint should be aspirated and cultures made. In bone disease the cause is usually staphylococci or streptococci and the treatment that already described. In typhoid and paratyphoids it may be due to the causative bacilli. In scarlet fever it is usually due to strepto- cocci. In other cases it may be due to other microbes, such as the Bacillus coli or pneumococcus. The initial dose of all these microbes is 2\ million, and the progression 2|, 5, 7^, 10, 15, 20, 30, 50, 75, 100 million, and so on. If the joint is to be saved treatment must be prompt and energetic. Repeated aspiration or free drainage is essential. In both acute suppuration of bones and joints intravenous antiseptics are often a most useful adjuvant treatment ; 3 — 5 c.c. of a o'l per cent, solution of sodium salt of di-iodosalicyclic acid, or if this fails, eusol or chloramine T. should be tried. 148 Bones, Joints, Wounds. Rheumatism. — Rheumatic conditions, like many others, appear to be septicaemias, with focal mani- festations. In typhoid fever, for instance, the focal manifestations are in the intestine ; in pneumonia, in the lungs ; in rheumatic infections, in the joints, muscles, or nerves, while other organs, such as the heart and kidneys, may be involved. The clinical conditions fall naturally into two groups — the acute and chronic ; and this classifica- tion is suitable pathologically, for the chronic cases, unless sometimes when they are a sequel to the acute, are usually complicated by secondary infec- tions, while the acute conditions are generally produced by a single infection. They all appear to agree in having a primary focus of infection, from which the blood and other tissues become infected. Acute non-suppurative inflammations of joints occur in rheumatic fever, gonorrhoeal infections, and acute gout. Acute gout will be considered with the chronic variety ; acute gonorrhoeal arthritis need not be considered here. Pathology, — In Rheumatic Fever the most common primary focus of infections is in the tonsils, adenoids or gums ; from these the blood stream becomes infected via the lymphatics. The onset of the fever is accompanied by lesions in the joints, where there is considerable inflammatory infiltration of the subsynovial and periarticular tissues, the cartilages are swollen, their cells pro- liferated, and there is more or less effusion into the joints. Lesions in other tissues may follow — endocarditis (which is the rule rather than 149 Therapeutic Immunisation. the exception), myocarditis, pericarditis, pleurisy, pneumonia. Bacteriology, — The causal organism has been studied by many people, notably Poynton and Payne and Beattie, and has received various names — e.g., the Diplococcus rheumaticus. It is morphologically and culturally identical with the streptococcus commonly found in pyorrhoea alveolaris, tonsils and adenoids. It can be isolated from the primary lesion, from the joints, from the blood, and it will most probably be found in the urine and faeces in these cases. As in the case of all other microbes, its virulence varies. Prophylaxis. — Since there is nearly always a primary lesion in the regions already indicated, and this lesion is usually present for a longer or shorter time before the symptoms of acute general infection arise, it is obvious that the clearing up of such training grounds for pathogenic microbes will prevent the onset of the general infection. Tonsils and ade- noids should be removed, the streptococcus isolated from them or from the pus from the gum, if that is the lesion, and a course of vaccine given. The sequence of doses, 2i, 5, 7I, 10, 15, 20, 30, 50, 75, 100 million, will usually be found suitable and adequate. Care must be taken that the patient should not be over-fatigued or exposed to chill for twenty-four hours after a dose. The intervals must be regulated by the occurrence of reactions. No dose must be given with a shorter interval than forty-eight hours. If reactions, focal or general, occur, the next dose must not be given until three days after all signs of reaction have disappeared. 150 Bones, Joints, Wounds. Treatment. — I think I may fairly state that the sole methods of treatment at present in use are rest and salicylates. As to the adequacy of these measures, I will quote an article by French in the Medical Annual for 1916. He says : The fact that salicylates in rheumatic fever do practically nothing towards curing the disease is apt to be lost sight of. What salicylates do is to bring down the temperature and reheve the joint pains, an immense boon to the patient, but the pains will recur if the salicylates are stopped, up to a period which is approximately the same as used to be the case before salicylates were employed. ... It is, however, probable that the mere fact that salicylates relieve the joint pains renders the severity of the subsequent valvular heart disease even greater than before ; for endocarditis is not prevented by salicylates, and some patients who would rest in bed longer, if they were in pain, get up, and add unnecessary strain to their inflamed heart valves ; when not being in pain, they believe they are cured of their acute rheumatism." The universal method of treatment then is entirely inadequate, either to cure the disease or prevent relapse. My personal opinion is that a combination of chemo- and immuno-therapy will give the best results. I know from clinical experience that an iodine salicylic acid compound in the form of the sodium salt of the di-iodosalicylic acid is a powerful intravital killer of streptococci, and I think it would be well worth a trial in acute rheumatism. The doses 151 Therapeutic Immunisation. I would suggest would be 2 to 5 c.c. of a i per cent, solution given daily intravenously. As soon as possible an autogenous vaccine should be made, the dose being 2|, 5, 7I, 10, 15, 20 million, and more if necessary. Even if a vaccine is not used in the acute stage, as I am quite sure it should be, it should be used in order to prevent relapse, which is notoriously common after an attack. Acidosis — so constant in the disease — should be combated by giving sodium citrate until the urine is amphoteric. Chronic Rheumatism. Pathology, — In subacute and chronic rheumatism the exudate in the joint and surrounding tissues becomes gradually organised. The cartilages may be at first unaffected, or may be so only near their margins, where they may become eroded. Later these erosions may spread until the whole cartilage is destroyed, and bony ankylosis may result from spread of the infection to the bones {rheumatoid arthritis). In other cases the cartilages may be eroded and destroyed where there is pressure, while they become hypertrophied and ossified at the edges, so as to produce osteophytes, some of which may be broken off, and become loose in the joints. Where the bare bones are in contact, they become polished and atrophied. This atrophy may be so extreme that eventually the whole head of the bone disappears {arthritis deformans) . In chronic gout sodium urate, or the urates of calcium, magnesium, or ammonium, become de- Bones, Joints, Wounds. posited in the articular cartilage, which becomes eroded. Later these urates become deposited in the synovial membrane, periarticular tissues, liga- ments, tendon sheaths in the periosteum, bursae, deep connective tissues, and subcutaneous tissue. Chronic rheumatism attacks men and women of all ages, and gout attacks people from middle age onwards, who are usually of an alcoholic habit. Rheumatoid arthritis affects people, usually females, between 20 and 40, and arthritis deformans is com- monest in females between 40 and 60. I am perfectly aware that it is the general opinion that each of these clinical conditions — rheumatism, rheumatoid arthritis, arthritis deformans and gout — has a different etiology. I have reason to think, however, that this is not the case, but that the mechanism of their production is the same, and that the differences in the pathological condition are due to differences in the quality of either the toxins or the tissues attacked by them, and the quantity of urates in the patient's circulation. This opinion has been reached as the result of observing that they all have similar foci of infection other than those of the joints, and as the result of favourable effects on the joint conditions produced by measures adopted to cure these other lesions. For the large majority of all such patients have chronic infections in the upper alimentary or respiratory tract, the microbes from which can and do infect the rest of the gastrointestinal tract, which is evident from signs and symptoms. These microbes produce the primary infection, and lower the resistance of the 153 Therapeutic Immunisation. tract ; the colif orm microbes inhabiting the intestine then become pathogenic, so that there is a mixed infection. This chronic inflammation not only interferes with normal digestion by interfering with the proper production of digestive enzymes, but also produces abnormal breakdown products of ingested foodstuffs, such as abnormal amino-acids, abnormal in quality and quantity, besides aromatic amine compounds, which produce rise of blood pressure. In addition to the chronic infection in the intestinal tract, there can be no doubt that microbes from the foci of infection, both primary and intestinal, are passing continually into the circula- tion. Quite commonly such microbes are excreted by the kidneys, and can be isolated from the urine. There are thus continuously passing into the blood products from normal and abnormal digestion and micro-organisms. As a rule, much more protein than is necessary for nitrogenous equilibrium — that is, for the maintenance of the nitrogen element in the structure of the protoplasmic molecule — is ingested. The superfluous amino-acids to which it is reduced are deaminised, in the intestinal cells especially, and in the muscles, and the resulting ammonia is synthesised into urea in the liver. In fatigue of the muscles and in abnormal meta- bolism produced by fever, where there is anoxaemia, acids are formed, such as sarcolactic acid, and these, getting into the circulation, interfere with the normal metabolism, since the intracellular and tissue ferments work best in an alkaline medium. Any- thing that leads to an increase of acids from the 154 Bones, Joints, Wounds. intestine, such as are produced from deaminised amino-acids, will aggravate the condition, or any poison which interferes with oxidation in the tissues, such as alcohol. Again, the interference with the oxidation in the tissue cells may be due to microbial infection. I have had one patient in whom an acute exacerbation of gout was brought on by over-indul- gence in tobacco. In all these conditions an abnormal amount of uric acid appears to be formed — and it is not — as it is normally — changed into the harmless urea. In gout it is deposited in the inflamed tissues in the form of salts. To sum up, the original condition appears to me to be produced by microbes from a focus of infection, supplemented by secondary infections, and is maintained by vicious circles produced by the abnormal metabolic products formed — {a) in the intestine, (&) in the tissues. Such is the hypothesis on which the treatment of these conditions is founded. If it is correct, then removal of the infecting focus and reduction of the action of the microbes in the intestine ought to pro- duce cure if the tissues affected are not too damaged to allow of this result. And this I have found to be so. By the methods described below several cases of typical gout have been cured. Prophylaxis. — As in the acute cases, the prophy- laxis of chronic rheumatic joints consists in the clearing up of the sources of infection that pro- duced them. The first twinge of rheumatic pain should be sufficient warning to the patient that he 155 Therapeutic Immunisation. must have his microbial inhabitants investigated, his foci of infection cleared up, and his resistance in- creased to the microbial inhabitants of his intestine. Treatment consists in inoculation with a vaccine made from the microbes found in the focus of infection, with a vaccine made from the patient's coliform bacilli and with a vaccine made from any microbe, other than B, coli or streptococci, which is being excreted from the patient's urine. If staphy- lococci are being excreted by the kidneys, strepto- cocci isolated from the gums, and coliform bacilli from the intestine, the series of doses would be in the order mentioned : — 25 million + 2j million + 2j million 50 5 5 75 „ + 71 , , + 5 100 „ + ID ID „ 150 „ + 15 , , + 15 „ 200 „ + 20 , + 20 and so on up to 2,000 + 200 + 200 million or more. Not uncommonly other microbes than the strepto- cocci are responsible for the primary infection. In several cases I have found Gram-negative bacilli, not described, in the gums or being excreted in the urine. The initial dose of these is 2| millions. One such bacillus was motile, it did not liquefy gelatine. It produced acid, but no clot in milk. It produced acid and gas in glucose, saccharose and mannite. It produced acid very slowly, but no gas in lactose. Another, feebly motile, produced acid in saccharose and glucose. It did not ferment lactose 156 Bones, Joints, Wounds. or mannite in five days, and produced acid and clot in milk. Another, non-motile, produced acid in lactose, saccharose and glucose, but not in mannite, and acid and clot in milk. So that many different kinds of these Gram-bacilli appear to infect. The correction of acidosis is particularly important in the treatment of these conditions, and the control of reactions by iodine therapy most helpful. Muscles. — Muscular rheumatism or fibrositis is investigated and treated in exactly the same manner as that of the joints. Infected Wounds, Compound Fractures, etc. Pathology. — The cavity of the wound is filled with blood clot, and this clot extends along the blood vessels as far as the nearest uninjured vessel to which it is joined. Portions of tissue, muscle, bone, which have been separated off from their nerve and blood supply are undergoing necrosis. In the case of wounds made by projectiles there is the complication of the presence of foreign bodies, metal, portions of clothing and suchlike. If the wound is aseptic the clotted blood, injured tissues, and so on, become invaded by phagocytic cells and plasma from the surrounding uninjured capillaries. Their removal is also brought about by autolysis and absorption by the lymphatics and veins. In the case of necrosing bone the process is so slow that it acts as a foreign body. When the effused blood is absorbed the fibrinous exudate is organised by the invasion of fibroblasts, derived from the 157 Therapeutic Immunisation. division of connective tissue cells, and new capil- laries are formed by the budding of cells from the walls of the capillaries which join together and become canalised. These are later obliterated by the fibrillation and contraction of the matrix in which they lie, as are the connective tissue cells that sur- round them. The surface of the wound is covered by the spreading over it of epithelial cells derived from the deeper layers of the epidermis round its margins. If the wound is infected the conditions present form a perfect culture medium for the development of micro-organisms, and the general system is easily invaded through the lymphatics and the blood vessels, the clots in the injured branches of which become infected. This general infection is aided by the general lowering of the activity of the body by shock and by the absorption of breakdown products produced by normal methods and the action of bacterial ferments. General infection is ' especially severe after bone injury, owing to the greater difficulty in it of walling off the infection by the processes of inflammation. It is evident that the conditions must be suitable for the bacillus of malignant oedema and of the B. perfringens to produce gas, since these microbes are often isolatable from wounds where no gas is being formed. Probably a sufficient activity of aerobic microbes is necessary to produce a sufficient degree of anaerobiosis. The gangrene is largely due to the gas separating the tissue elements from each other as well as to the toxins of the microbes. 158 Bones, Joints, Wounds. Bacteriology. — The most common aerobic microbes found in infected wounds are staphylococci, jB. pyo- cyaneus, streptococci, B. coli, other coKform baciUi, and various Gram-negative baciUi not classified, some of which are gelatine liquefiers, and probably belong to the B, proteus group. Diphtheroids and other Gram-positive bacilli are also very common. Besides these aerobic microbes gunshot and other wounds contaminated with soil and decomposing organic matter are liable to become infected with anaerobic microbes, the most important of which are the tetanus bacillus, the bacillus of malignant oedema and the B, perfrigens {B. aerogenes capsulatus of Welch). All these microbes are spore-forming, and the last two produce gas in the tissues. Gas is also produced by other anaerobes and aerobes, e.g., B. aerobicus sepis, but they are rarer. Prophylaxis and Treatment. — Owing to the great variety of microbes found in infected wounds it is practically impossible to attempt to prevent focal and general infection by the use of stock vaccines. The prevention of severe systemic infection and of the invasion of uninjured tissues is in the hands of the surgeon, whose aim must be the most complete possible removal of foreign bodies, blood clot and free drainage. Wherever possible a vaccine con- taining all the aerobic microbes isolatable from the wound grown on human blood agar should be made at the earliest moment if there is suppuration with signs of general infection. This is additionally important where, as is usually the case in war, especially on cultivated soil, the wound is infected 159 Therapeutic Immunisation. with soil and faecal micro-organisms containing anaerobic gas- producing microbes, for it appears that unless aerobes are present these anaerobes cannot produce their disastrous results. My own opinion about the saline-antiseptic con- troversy is that, with one exception perhaps, no antiseptic in use is effective in the depths of a wound, for seldom does it get there, and if it did, it would only be effective in such a strength that it would do more harm than good by kiUing the tissue cells as well as the microbes. Sterile isotonic saline is undoubtedly the best fluid to use for the early wash- ing out and irrigation of a wound. When specific antibodies have been produced by the proper use of vaccine then the judicious use of a slightly hypertonic saline is sometimes useful, but it must always be remembered that, as Wright has demon- strated, it has an antiphagocytic action and should, if used at all, be only used intermittently. The antiseptic I hold a brief for is iodoform.* When split up, as it is in the body, especially in the presence of pus, the iodine is germicidal ; it is antitoxic, destroying the toxic, but not the antigenic property of microbial toxins, while Hamburger has demonstrated the fact that iodoform as such increases the phagocytic power of phagocytic cells. The iodoform must be dissolved in ether, the vapori- sation of which leaves it in a finely divided state on the surface of the wound, while the ether itself has an antiseptic action. Sixty-six milligrammes * This was written before the acryl compounds were intro- duced. I have no practical experience of these. i6o Bones, Joints, Wounds. (i grain) of iodoform are soluble in i c.c. of pure ether. Ten c.c. containing lo grains will be sufficient to leave a fine deposit on the whole surface of most wounds if injected into the bottom of them, and in this dose is not likely to produce iodoform poisoning. Further, the absorption of iodoform or its breakdown products from the surface of the wound is most valuable in combating general infection. The iodo- form in ether given intravenously in doses of | to I grain daily is extremely valuable for this purpose. Another drug which is most valuable for combating general infection with many kinds of microbes is di-iodosalicylic acid in the form of a i per cent, watery solution of its sodium salt ; 3 — 5 c.c. is given every day intravenously. Vaccines are especially useful when there is acute general infection, where the wound has become slug- gish and indolent and where the patient is becoming cachectic. Vaccines will hasten the heaUng of all suppurating wounds. As in all other cases, it is essential for success that the vaccine should contain all the microbes that are infecting the patient, that the doses should be steadily increased until the result is attained, that the vaccine should be given at suitable intervals, which are determined by the absence or degree of focal and general reactions. If no obvious reaction occurs the next dose may be given in forty- eight hours ; if reactions occur the next dose should not be given for three days after all signs of these reactions have disappeared. If the reaction is severe after an injection it can be controlled by 161 " Therapeutic Immunisation. intravenous iodoform or di-iodosalicylic acid already mentioned, or iodine-menthol-radium compound in I c.c. doses given subcutaneously. The vaccine must not be given into an area the lymphatics of which drain into infected lymphatic glands. Frequently, owing to the profuse growth of one microbe in the primary culture, an important microbe may be missed ; after some doses this microbe is reduced or has disappeared, and fresh culture will then give the other microbe. A mixed infection containing B, pyocyaneus is a good example. This poisonous microbe grows very freely and rapidly overgrows everything else. The original smear may show other microbes, for instance, streptococci. A B, pyocyaneus vaccine is made ; a dose of i or 2 million is quite a big enough initial dose, and the series 2, 4, 8, 10, 15, 20, given ; a fresh culture will then enable the streptococcus to be isolated. If the patient is not doing well with the vaccine his flora should be reinvestigated, for the wound may have become invaded with other microbes, or, as we have seen, a microbe which was there in small numbers, as compared with the others, may have been missed ; as the others disappear it may become aggressive. The initial dose of staphylococci is 25 million, as a rule ; if the case is very acute 10 million is sufficient, and the series 50, 100, 150, 200, 400, 600, 800, 1,000, 1,500, 2,000, and so on ; 2|, 5, 71, 10, 15, 20, 30, 50, 75, 100, 150, 200, or higher, in the case of all the others. If the general infection is severe the progression i, 2, 4, 6, 8, 10, 15, 20, and so on, is the safest to use, as in the case of the Bacillus pyocyaneus, 162 CHAPTER X. THE SKIN. Erysipelas is an acute spreading inflamma- tion of the skin accompanied by symptoms of acute generalised infection. It is caused by infection with the Streptococcus erysipelatis. There is a definite spreading edge, the inflammation subsiding behind it, the tissues having acquired a local immunity. Pathology. — There is acute hyperaemia and cellulo- fibrinous exudation into the dermis. The strepto- cocci are found in the tissues, but chiefly in the lymphatics, along which they spread. The cells of the epidermis are swollen and vacuolated, and often undergo colliquative necrosis, forming bullae. Frequently the infection involves the subcutaneous tissues, a cellulitis resulting. Abscesses may form or sloughing of the skin from gangrene. Bacteriology,' — The streptococci which have no special morphological or cultural characteristics are easily isolated from the blebs. They grow strongly on blood- agar. Treatment. — Specific sera are obtainable com- mercially, which frequently give excellent and rapid results. Twenty-five c.c, repeated in twenty-four hours, is a suitable dose for an adult. Even if the serum is successful an autogenous vaccine is necessary, as the disease is very liable to 163 ^^-^ Therapeutic Immunisation. relapse. The dose should be 2|, 5, 7I, 10, 15, 20, increasing to 50 or 100 miUion, given at suitable intervals. The doses should be given subcutaneously into an area as far away as possible from the site of the disease. Vaccine and serum may be given together as soon as the vaccine is available. Anthrax. — The anthrax bacillus produces two kinds of lesions in man, viz., * malignant pustule ' of the skin and acute inflammation of the lungs, or ' woolsorter's disease.' The mortality of the former has been greatly reduced by serum therapy. Woolsorter's disease is almost invariably fatal. Pathology, — The infection of the skin occurs through abrasions or from bites of insects. A pustule or carbuncle results. The papillary layer and the corium become infiltrated with inflammatory cells, exudate, and extravasated blood. In the inflamed tissues are many anthrax bacilli. The cells of the overlying epidermis undergo lysis, with the conse- quent formation of blebs. If not checked the infec- tion spreads and bacilli make their way into the circulation, producing generalised infection and death. Bacteriology, — The anthrax bacillus is 5 — 10 ^ x I — 1*5 Gram-positive and non-motile. According to Besson and Hutchens, the ends of the bacilli seen under a high magnification show a ragged or sinuous rather than straight edge, as though the bacillus had been roughly broken. This, they say, is quite characteristic. Under suitable conditions the microbe produces a central spore. It is aerobic and grows well on ordinary media. 164 The Skin. Immunity. — Local immunity is marked ; the skin is more highly resistant than the lungs. Serum of immunised animals contains immune-body, which, when activated, has a bactericidal effect and leads to effective ingestion and digestion by phagocytes. It also contains a certain amount of antitoxin, probably anti-endotoxin. Marmier has isolated a toxin which may either be an exotoxin or an endo- toxin liberated by lysis of the bacilli. The filtered blood of infected animals appears to be toxic. In human beings one attack, if recovered from, immunises. The isolation of morphologically characteristic bacilli from a characteristic lesion is sufficient for practical diagnostic purposes. If a septicaemia is present the microbe can be isolated from the blood and urine. Prophylaxis. — Pasteur immunised sheep and cattle by two inoculations. In Pasteur's method the bacilli are alive but are attenuated in virulence by being grown at 42° C. — in the case of the first vaccine for twenty-four days, in the case of the second vaccine for fourteen days. A certain per- centage of animals are killed by this method. Larger doses of a killed vaccine would probably be suffi- ciently effective, and would not kill any animal. Undoubtedly, workers engaged with hides and wool, especially the latter, since woolsorter's disease is always fatal, should receive prophylactic inocula- tion with a killed vaccine. Treatment. — Very efficient sera, such as Sclavo's, are to be had commercially for the treatment of the 165 Therapeutic Immunisation. disease. Forty c.c. should be given at once and repeated if necessary. There is frequently a sharp rise of temperature following the injection, but it soon subsides. If any anaphylactic symptoms appear they can be controlled with pituitrin in i c.c. doses. Seborrhcea, Comedones, and Acne.— These con- ditions are produced by overaction of the sebaceous glands of the skin due to infection with the acne bacillus. Pathology. — In seborrhcea the gland swells and the increased secretion (sebaceous matter and desquamated cells) dries on the surface (5. sicca, dandruff), or when more profuse leads to a greasj^ condition of the skin (S. oleosa). The nutrition of the hair root is frequently interfered with, with conse- quent falling out of the hair. In comedones the secretion becomes dried at the orifice of the gland, where it forms a plug which becomes dark in colour owing to admixture with dirt and, possibly, with a special pigment. In acne the blocked gland becomes distended, forming a papule which may become red from hypera^mia and periglandular invasion with inflam- matory cells [Acne simplex). If the papule then becomes infected with staphylococci suppuration usually results {Acne pustulosa). The suppuration frequently spreads to the subcutaneous tissues, considerable pockets of pus resulting. Chronic inflammation often leads to great pitting and fibrosis of the skin. Bacteriology, — In seborrhcea and comedones squeezing of the skin produces worm-like masses of l66 The Skin. greasy material. Staining of this material shows large numbers of short Gram- positive acne bacilli, which can be grown by culturing on + 30 agar anaero- bically. The colonies thus grown, which take ten to fourteen days to become characteristic, are buff- coloured round colonies, the colouring being deeper in the centre, where the colony is characteristically heaped up. I believe the bacillus exists in both a coccal and bacillary form, for if the cultures are taken out of the anaerobic chamber after a fortnight and grown aerobically each colony (consisting of bacilli) becomes surrounded by a halo of Gram-positive cocci indistinguishable from staphylococci. Further, by growing on different media anaerobi- cally I have been able to turn the coccal form into the bacillary form and this back again into a coccal form. The media used (a + 10 glucose agar and a serum medium) were equally suitable for growing ordinary staphylococci. In Acne ptistulosa staphylococci are always present with the acne bacilli. Treatment. — Seborrhoea and comedones can be treated by acne bacillus vaccine alone, but if there are any pustules a staphylococcus vaccine must be used as well. The initial dose of each is 100 million and the series 100 + 100, 200 + 200, 400 + 400, 600 + 600, 800 -f 800, 1,000 + 1,000, 1,500 + 1,500, 2,000 + 2,000, and so on up to, at least, 5,000 million + 5, 000 million. In old-standing cases very large doses up to, perhaps, 30,000 million -f 30,000 million may have to be attained before the patient is permanently well. 167 Therapeutic Immunisation. Chronic intestinal infection is frequently a predis- posing cause and must be suitably treated if present. Ethereal antiseptic soap is the best thing to wash the skin with. Comedones and acne pustules ought to be squeezed out or evacuated as they appear. FuRUNCULOSis.' — Boils and carbuncles are usually due to staphylococcal infections, the infection starting, as a rule, in the sweat glands, sebaceous glands or hair folUcles. Pathology, — In generalised furunculosis the staphy- lococci are circulating in the blood ; in other cases they may be rubbed into the skin. In boils there is one focus of infection, while carbuncles have several centres which become confluent. The infection produces necrosis of a mass of tissue which is sur- rounded by an area of acute inflammation; the central slough becomes surrounded by pus, which burrows towards the surface, where it discharges. The inflammation spreads beyond the skin into the subcutaneous tissues. Bacteriology, — Furunculosis is caused by Staphy- lococcus aureus as a rule, sometimes by alhus or citreus ; rarely by other microbes, such as strepto- cocci. When making the culture it is well to take the specimens from the granulation tissue wall after evacuating the pus. Treatment, — Stock polyvalent vaccines often do quite well in furunculosis and may be used pending the making of an autogenous vaccine. In recent cases a course of vaccine consisting of lOO, 200, 400, 600, 800, 1,000, 1,500, 2,000 million will generally be sufficient. In chronic cases it may be necessary to 168 The Skin. attain a dose of 10,000 million or more. It is always necessary to inquire into the state of the alimentary canal and to search for a focus of infection in the upper ahmentary and respiratory tract. If the infecting microbe is a streptococcus the series 10, 20, 40, 60, 80, 100, 150, 200 million or more will be generally found suitable. The intervals between the doses may be usually four to six days at first in staphylococcus infections, increasing the intervals as the dose gets larger. After 4,000 milHon the intervals should be ten to fourteen days. Sycosis is caused by an infection of the hair foUicles and perifoUicular tissues. Pathology, — The inflammation starts in the peri- follicular tissue and spreads into the hair follicle, the pus exuding from the mouth of the follicle round the hair. The centres of infection become confluent and a crust of dried pus and desquamated cells forms, underneath which is a granulating surface. Except in bad cases the hair follicle is not destroyed. Bacteriology, — The disease is, as a rule, caused by the Staphylococcus aureus, which is easily isolated from the pus. The hair roots should be examined to make sure that ringworm is not present. Treatment, — The disease heals up readily with an autogenous staphylococcus vaccine, the series being 100, 200, 400, 600, 800, 1,000, 1,500, 2,000, 3,000, 4,000 million or more. As a rule intervals of six days should be left between the earlier doses, increased to ten days between the larger. 169 Therapeutic Immunisation. Impetigo is an infection of the skin produced by staphylococci ; sometimes streptococci are said to be the cause ; I have never found them in the disease. The disease occurs in epidemics and spreads by contact, towels, etc., from one area of the skin to another and from one person to another. The areas are, as a rule, small, and there is little infiltration. When the areas are large and there is more infiltration, the condition is known as ecthyma. Closely related to this disease is pemphigus neona- torum, also caused by staphylococci, which often occurs in epidemics. Pathology, — The inflammation starts in the dermis. The overlying cells of the deeper layers of the epidermis undergo colliquative necrosis, so that a bleb forms ; this bursts through the horny layers and the secretion dries into a yellow crust. In pemphigus the microbe is in the circulation, the blebs in the skin being focal manifestations. Treatment, — In ordinary local treatment (a strong iodine ointment or liq. iodi fort, being the best), the condition can be cleared up with an autogenous vaccine, the series being lOO, 200, 400, 600, 800, 1,000 million, or more if necessary, of the staphylo- coccus vaccine. In infants with pemphigus the initial dose should be 25 miUion, followed by 50 and 100 million. Eczema is a general term for dermatitis which may have many primary causes. Staphylococci are generally found in the lesions and the infection with them may be the primary cause, but frequently the resistance of the skin is lowered first by external 170 The Skin. irritation, chemical, thermal. X-rays, or mechanical or chronic poisoning or infection from the gastro- intestinal tract, as in gout. Pathology. — The inflammation generally starts in a papilla, which shows the usual signs of inflamma- tion (papular eczema). This may work downwards into the chorium and spread so that extensive areas may be involved. The overlying layer of cells of the epidermis becomes hypertrophied. This may lead to over-keratinisation with the formation of scales, or the Malpighian cells may undergo lysis with the formation of bullae ; the shedding of the cuticle over these leaves a weeping surface. This weeping sur- face may be so extensive as to cover the whole body (weeping eczema). Bacteriology, — The infecting microbe can be easily isolated from pustules or bullae, or a weeping surface. In dry erythematous or scaly eczema the best way to obtain the microbe is to make an artificial bulla by means of blistering fluid and obtain the culture from the raw base of this. Much the most common microbe found is the staphylococcus, but it is by no means the only cause. I have isolated in one case streptococci and Gram-negative bacilli of the B, proteus group ; later during a relapse Staphylococcus aureus was isolated in pure culture from this case, the other microbes having disappeared after a few doses of vaccine. Treatment, — Autogenous staphylococcus vaccine, as a rule, gives very good results. In chronic case very large doses must be attained. The initial dose is 100 million and the series loo, 200, 400. 600, 800, 171 Therapeutic Immunisation. 1,000, 1,500, 2,000, and so on, up to 30,000 million or more if necessary. If the patient has a chronic alimentary infection, as in rheumatism and gout, it must be treated suitably. Of course, chemical or other irritation must be removed. If streptococci are the cause, or other microbe, the initial dose is 2| — 5 miUion, and the series 2|, 5, 7|-, 10, 15, 20, up to 500 miUion or more. 172 CHAPTER XL VASCULAR SYSTEM, LYMPHATIC SYSTEM, NERVOUS SYSTEM, EYE AND EAR. Microbial infections of the vascular system are usually associated with some focus of a disease from which the blood stream becomes infected, either by direct invasion through the walls of a blood vessel or via the lymphatics. Most of these sources of infec- tion have already been noticed, e.g., the ent ericas, rheumatic fever, puerperal fever. In other cases the infection seems to be carried into the interior through apparently intact mucous membrane by phagocytes, which the ingested microbes eventually kill, or into the lymph stream, for instance, through the stomata in the alveoli of the lungs. It may be that there is always some local inflammatory change insufficient to give rise to symptoms. A good instance of a septicaemia without an apparent focus of infection is Mediterranean fever, which may suitably be considered here. Undulent or Mediterranean Fever is caused by a minute bacillus, the B, Melitensis. Typically, the temperature is undulating, rising steadily to a maximum, then falKng by lysis to 99 deg. F. or less for some days, then rising again as before. Severe perspirations are a feature of the symptoms. This sequence of events sometimes continues with ordi- nary expectant treatment for months, even for a year 173 Therapeutic Immunisation. or two. In the worst cases, which are frequently fatal, the patient is in a severe ' typhoid ' state with a continuously high evening temperature and delirium. In other, abortive, cases there is only one temperature period. Pathology, — There are no particular pathological changes to be described, the spleen and liver are enlarged and the microbe can be isolated from them by puncture during life, as it can from the blood and urine and also from the kidneys post mortem. Bacteriology, — The B, Melitensis, or, as it is usually called, the Micrococcus Melitensis, is in its coccal form about 3 in diameter ; if grown on suitable media it is in appearance and size identical with the influenza or whooping-cough bacillus and, as in the case of these microbes, occasional longer forms are seen. It is aerobic and Gram- negative. It grows excellently on fresh human blood-agar. A catheter specimen of urine is centrifuged and the deposit sown thickty on the slopes. During the fever, especially during the rising period, the microbe can, usually, be isolated from the blood; lo c.c. of blood taken from an arm vein should be put into 50 c.c. of broth and after some days subcultures made on blood-agar. Subculturing may have to be con- tinued for ten days or more before colonies appear. As with other delicate microbes, the media must be made from fresh meat and not heated above 100 deg. C. in their manufacture. The colonies when they appear first are translucent and I — 3 mm. in diameter. Afterwards they become raised and white, and, as they become older, 174 Vascular System. brown in appearance. The microbe will not liquefy gelatine and will not grow at 22 deg. C. Prophylaxis. — The prevention of the disease is very simple and consists in not drinking goat's milk unless it is sterilised. As the poorer classes cannot be persuaded to do this, preventive inocula- tion would probably be effective. The doses would have to be large, 500 to 2,000 million at least. Treatment. — No effective serum has been pro- duced. Vaccine therapy is very effective. In ordinary undulent cases the initial dose is 50 million, and the subsequent series 100, 150, 200, 300, 500, 750, 1,000 million and higher, given at suitable intervals. In ' typhoid ' cases the initial dose should not be more than 25 million. If possible the vaccine should be autogenous and grown on the patient's blood. Heart Disease. — Infections of the heart are always associated with septicaemias and occur in such diseases as rheumatic fever, scarlet fever, pneu- monia and gonorrhoeal septicaemia. By far the most common causes of endocarditis, pericarditis and myocarditis are microbes belonging to the pneumo- streptococcal group, to which the microbes causing scarlet fever, rheumatic fever and pneumonia belong. Pathology. — Pericarditis. — The pericardium may be infected through the blood stream, as already mentioned, or by extension of infection from neigh- bouring organs, such as the heart, lungs, pleura, mediastinal glands, or through the diaphragm from abdominal infections. The first histological changes are hyperaemia with 175 Therapeutic Immunisation. increased exudate of fluid having a large amount of fibrin, which becomes deposited on the surface, and migration of leucocytes. The endothelial cells become cuboidal and desquamate or bud off. The causative microbes are seen in the cellulo-fibrinous mass or phagocyted in the cells. If these microbes are pyogenic they produce suppuration, if their toxins produce lysis of the capillary cells the effusion is haemorrhagic. If there is little effusion the peri- carditis is ' dry.' If the stomata are blocked with fibrin plugs the effusion may be very large. The fibrin may become organised and adhesions form, or the visceral and parietal layers may become firmly united in this way. Sometimes the whole process ends in calcification. In MYOCARDms the infection either spreads into the muscle from the pericardium or endocardium, or is carried to it by the blood stream. The earliest change is swelling of the muscle cells with obscuring of the nuclei (cloudy swelling) ; this is accompanied by hyperaemia, migration of leuco- cytes into the connective tissue and proliferation of connective tissue cells. In pyogenic septicaemias small abscesses result. If the infection is overcome the changes may completely resolve. In other cases organisation of the exudate results, with consequent increase of fibrous tissue, some of the muscle fibres undergoing fatty degeneration. In some non-pyo- genic infections, e.g,, pneumonia, the muscle cells are so poisoned that fragmentation occurs, with consequent dilatation of the heart, which may be so extreme that the heart stops beating. 176 Vascular System. Endocarditis. — The most common and impor- tant sites of endocarditis are the valves, and the most common parts of them to be affected are those which are appHed together during the closing of them ; but any part of the intima of the heart may be infected. Pathology. — The processes are briefly as follows : microbes are deposited on the surface, probably being clasped on to them from the blood during the closure. The endothelial cells in contact with the microbes become cuboidal and ingest the microbes and are killed and thrown off. On the denuded surface blood platelets are deposited and afterwards fibrin and leucocytes. The subjacent tissues react and there is proliferation of small round cells and oedema. If the infection is very virulent the microbes entangled in the cellulofibrinous deposit destroy the subjacent tissues and an ulcer results which may perforate through or destroy the whole or a large part of the valve. In less virulent infec- tions the fibrinocellular deposit may attain large proportions and become organised by the ingrowth of fibroblasts and capillaries. This occurs early in the case of the tricuspid and mitral valves, which have blood-vessels in their proximal parts ; later, in the case of the aortic and pulmonary valves, which have not. When the patient survives the valves become distorted from contraction of the fibrous tissue and the damaged valves are liable to become more damaged from the increased strains they have to bear, with resulting increase of fibrous tissue from Therapeutic Immunisation. their reaction to these strains. The valves are also less able to resist fresh infections if they occur, as they so commonly do, mostly from the primary focus of infection. Prophylaxis and Treatment. — Since the heart valves once damaged can never be restored to normal, and, since once damaged, the sclerosis is likely to increase from strain reaction, it is all-important to prevent the occurrence of infection by destroying the primary foci likely to produce the septicaemia by vaccines and surgical measures ; and, if septicaemia occurs, to reduce its activities to a mini- mum by means of the methods already described for scarlet fever and rheumatic fever. Infections of the Blood-vessels. — There will be no necessity to discuss these separately, as those which occur as part of a septicaemia have the same etiology and treatment as heart disease and those which are produced by spread of disease from surrounding infection are only of separate interest, since they may lead to septicaemia or pyaemia. There is one condition of the arteries, how- ever, about which a word or two may be said, viz. : — Arteriosclerosis. — There are several methods by which this condition may be brought about. Leaving out syphilis and chronic poisoning, such as lead poisoning, there can be no doubt that acute and chronic septicaemia can produce this condition. Such septicaemias and toxaemias occur in gout and rheumatism, where, ' -not only is there chronic 178 Vascular System. bacteriaemia, but also chronic intoxication produced by abnormal intestinal and tissue metabolism; while also the balance between the various internal secretions is upset and the quality of them sub- normal or abnormal. Pathology. — The first change when a strain is put on the vessel wall is a thickening of the muscle coat; there is next a subendothelial collection of small round cells produced by reaction of the connec- tive tissues in this situation. If the cause of this hypertrophy is not removed fibroblasts develop in the intima and muscular coats, and there is also an increase of the connective tissue of the adventitia. The last state is fatty degeneration and the deposit of lime salts, turning the vessel into a rigid tube. The extent of recovery that is possible in an hypertrophied artery can best be reaKsed by remem- bering what happens to the arteries after parturition. I have seen the same thing occur in a case of very severe exophthalmic goitre in a man in whom there was a large pulsating artery on the surface of each greatly enlarged lateral lobe. Under treatment with, first, adrenalin and then pituitrin, the enlargement of the thyroid completely disappeared, leaving the hypertrophied arteries running a visible and tortuous course over where the enlarged lateral lobes had been. After some months these completely disappeared. In another case, which had been diagnosed as a case of cardio- and arteriosclerosis in a man of 55, the retinal arteries were tortuous, had the typical silver wire appearance and the veins were obliterated Therapeutic Immunisation. where they passed under them. After six months of treatment they were restored to an appearance normal for a man of the patient's age. So that a large degree of recovery of thickened arteries is possible and, unless they are calcified, worth trying for. The primary cause in some cases is not an intoxication, but a neurosis. Treatment must aim at (i) a permanent reduc- tion of high blood pressure ; (2) restoration of the salt content of the blood ; (3) removal of the fundamental toxaemia. Thyroid extract is by far the best way of reducing blood pressure. It should be increased to the patient's physiological limits and should be kept up for a long time. The salt content is restored by giving the salts of Trunecek's serum, which may conveniently be given in tablet form. Each tablet has the following formula : — Sod. chlor., '4 gramme. Sod. sulphat, '04 ,, Sod. cart., "016 ,, Sod. phosph., '012 „ Mag. phosph., '016 ,, Calc.glycerophosph., -012 „ Two should be given three times a day with ten ounces of water. The toxaemia should be cleared up in the way already described in the chapter on intestinal infec- tions. Even in neurasthenic cases the intestinal infection comes to play an important part as a factor in the vicious circle. 180 Lymphatic System. Lymphatic Glands. Lymphatic glands are usually infected through the lymphatics coming from an infected area or from a place where microbes get carried into the interior by phagocytes, which place is often a collection of lymphoid cells close to the surface of a mucous membrane, such as in the tonsils, respiratory passages and intestinal tract. The glands are places where the microbes are filtered off and so prevented from getting into the system, for in them there are particular facilities for phagocytosis. If their resist- ance is overcome inflammation of them results or the infection may be carried on into the vascular system. The lesions produced in connection with other areas of infection need not be separately considered. Since the usual type of plague is associated with enlargement of the lymphatic glands this disease may be briefly considered here. Plague is caused by the Bacillus pestis and is a septicaemia, sometimes without focal manifestations but generally with focal lesions in the lymphatic glands (bubonic plague), more rarely in the lungs (pneumonic plague) as in the terrible Manchurian epidemic. Pathology, — In bubonic plague the microbe is inoculated into the skin by fleas generally from infected rats. The most common agent is the rat- flea {Xenopsylus or Pulex cheopis). But infection from man to man can take place by the human flea [Pulex irritans) or bed-bugs [Cimex lectularius) . i8i Therapeutic Immunisation. The glands receiving the lymphatics from the area of skin first infected, where a haemorrhagic oedema occurs, are naturally the first to enlarge. In 50 per cent, of cases these are the inguinal glands, in 25 per cent, the axillary glands. Rapidly the other collections of glands are infected, e.g., the glands at the roots of the lungs, those of the mesen- tery and of the pharynx. The glands become enlarged and haemorrhagic, the surrounding tissues show haemorrhagic oedema. The blood-vessels and lymphatics of the glands are engorged and full of bacilli and desquamated and budded off endothelial cells containing the microbes. The lymphoid cells also proliferate and a number of large cells con- taining coarse basophile granules are present ; a few plasma cells are seen, but very few polynuclear cells. In abortive cases {pestis minor) the glands undergo resolution. As a rule necrosis takes place, the cells undergoing degeneration and the whole either becoming like lard or a semi-fluid gummy material. Haemorrhages are common owing to lysis of the endothelial cells of the capillaries. Haemorrhages from the same cause are found in the skin and internal organs, such as the liver and spleen, which also contain areas of necrosis. In pneumonic plague the lungs are primarily infected, the infection being conveyed by atomised droplets of sputum from one case to another. Pneumonia sometimes occurs as a secondary focus in bubonic plague, and haemorrhages from the lungs are not uncommon. There is no special pathological histology of the lungs requiring notice. 182 Lymphatic System. Bacteriology, — The B, pestis is, when seen in smears made from material withdrawn by puncture of the enlarged glands or otherwise, a short, fat. Gram-negative bacillus, 2 /x X i /x, with rounded ends. When stained with weak aniline dyes the ends stain more deeply than the middle. By varying the environment, as in the case with so many microbes, S. Roland has produced forms resembling micro- cocci, streptococci, bacteria, streptothrices and mould fungi. In broth the coccobacillus often forms chains, the masses fall to the bottom, leaving a clear supernatant fluid with sometimes a pellicle on the surface. If a layer of oil has been placed on the surface the microbes adhere to its under-surface and grow down into the broth in the form of stalactite. The bacillus grows as rounded white colonies on agar, glycerine agar and serum. When grown for vaccine purposes fresh human blood-agar should be used. The toxin of the microbe is probably an endo- toxin, which may be liberated by autolysis into fluid culture media. Roland has isolated a toxic nucleo- protein. Immunising sera, such as Yersin's, produced in horses by inoculating with gradually increasing doses of dead vaccine, followed by injections of suspensions of live bacilli, are powerfully bacterio- lytic. Lustig and Rowland have prepared antitoxic sera, the latter by injecting his toxic nucleoprotein. Any antibacterial serum cannot be of much use unless it contains antitoxins in sufficient amounts. 183 Therapeutic Immunisation. Any recovery under unaided conditions must be chiefly due to effective phagocytosis. Prophylaxis. — The case incidence and case mor- taUty of bubonic plague have been greatly reduced by preventive inoculation. In the Punjab in 1902 — 1903 the case incidence amongst the unin- oculated inhabitants was 7*7 per cent., and the case mortality 60* i per cent., while the figures amongst the inoculated were i'8 per cent, and 23*9 per cent, respectively. Haffkine's vaccine has been most largely used for the purpose. It consists of broth cultures grown for two months and sterilised by heating to 65 deg. C. ; 2*5 — 5 c.c. are given sub- cutaneously. The immunity lasts on an average twelve to eighteen months. The negative phase lasts, as a rule, not more than twenty-four hours. If there is any suspicion that the patient may have already become infected, a first dose of 2*5 c.c. com- bined with 10 c.c. of Yersin's or other serum should be given as a first dose and 5 c.c. of vaccine given after a suitable interval. Rowland has produced very good prophylactic results in rats by the injection of one minute dose ('02 — 'oooi mg.) of his nucleo- protein extract ; 10 c.c. of Yersin's serum protects, as a rule, for ten days. Treatment. — No treatment, prophylactic or cura- tive, is of the sUghtest use in pneumonic plague. Serum therapy appears to have some effect in the treatment of bubonic plague. Large doses must be used and frequently repeated until the temperature is normal and for some days after. Yersin's serum obtained from horses, in the usual way has been 184 Lymphatic System. mostly used ; lOO c.c. should be given at once, intravenously, and 40 — 60 c.c, subcutaneously or intramuscularly within twenty-four hours, and this dose repeated once or twice a day as long as is necessary. Rowland has protected rats with a serum pre- pared from horses by giving them an ascending series of doses ('Oi — 240 mg.) of his nucleoprotein. Control experiments with Yersin's serum failed. As it is essential in dealing with an easily lysed microbe like the plague bacillus that sufficient anti-endotoxin should be present in the serum, it is probable that Rowland's serum will be found more efficient than those prepared in the ordinary way. Rowland records eighty-seven cases of plague treated with vaccines. Of these all forty-three septicaemic cases died, while the forty-four non- septicaemic cases recovered. F. P. Connor has treated three cases of plague, one very severe, by repeated intravenous injections of 7 min. of tincture of iodine in i dr. of distilled water. All three recovered. Lymphadenoma (Hodgkin's Disease). — Several observers have isolated a diphtheroid bacillus from the lymphatic glands and in acute cases from the the blood in cases of this disease. Vaccines pre- pared from this microbe have given encouraging results in some cases. There are no infections of the other ductless glands peculiar to them. They are involved in septicaemias, but their treatment does not require separate mention. 185 Therapeutic Immunisation. Nervous System, With few exceptions, such as acute infections, for instance, cerebrospinal meningitis and meningitis occurring as complications of other infections, tuber- cular disease and syphilitic infections, little has been done to elucidate the cause of such diseases of the central nervous system as disseminated sclerosis, acute myelitis and the various other paralyses, and so on. It is interesting in this connection that Cruickshank has found that about 25 per cent, of the inmates of the Creighton Institute were excreting microbes in their urine, while acute mania has often the characteristics of an acute infectious disease. Cerebrospinal Meningitis. — Epidemic cerebro- spinal meningitis is caused by the meningococcus. The disease appears to start as an infection of the nasopharynx, a septicaemia results, and from these microbes in the circulation the central nervous system becomes infected. In some cases the infection of the meninges may occur directly from the nasal passages. Pathology, — The cerebrospinal fluid is purulent, containing numerous, mostly polynuclear, leuco- cytes and fibrin. The meninges show the usual signs of inflammation, ix,, distended blood-vessels and exudation. The vessels of the cortex of the brain and cord are distended and surrounded by aggregations of leucocytes. Many small haemor- rhages occur and sometimes larger areas of necrosis. The choroid plexuses are inflamed and the ven- tricles may become distended. In chronic cases 186 Nervous System. the closure by inflammatory processes of the foramen of Majendie and the other foramina may lead to internal hydrocephalus. Quite often septic arthritis and less often abscesses due to the meningo- coccus occur. Petechial spots are very common. Bacteriology, — The Diplococcus intracellularis or meningococcus of Weichselbaum is a Gram-negative diplococcus occurring frequently inside the poly- nuclear cells in the cerebrospinal fluid and in the pus from arthritis. It is very like the gonococcus in appearance, and like it is very particular as to the medium it grows on. Many special media have been advocated for its growth ; all that is neces- sary is that the medium should be made from fresh meat, should be accurately lo in reaction and should contain about i c.c. of blood, preferably the patient's, to each lo c.c. of medium. The cere- brospinal fluid should be centrifuged and the cultures, agar plates or slopes, made from the deposit. A good way also, if the microbes are not very numerous, is to add an equal part of the pus to broth, incubate overnight and then inoculate solid media. The cultures should be made without delay as the organism soon dies out unless kept at body tempera- ture. If the medium is suitable the microbe grows rapidly, the colonies being clear and regular in out- Hne and may attain several millimetres in diameter. The meningococcus ferments glucose and maltose slowly. It has no action on levulose, saccharose or inulin. For all practical purposes a case of menin- gitis in the cerebrospinal fluid from which are seen Gram -negative diplococci situated intracellularly 187 Therapeutic Immunisation. may be taken as being due to the meningococcus, pending a report on the cultural and serological characteristics of the microbe isolated. When the cultures are made from nasopharyngeal swabs the diagnosis is not so easy, since many varieties of Gram-negative cocci can be isolated from this region. Some of these, such as the Micrococcus catarrhalis, the Diplococcus pharyngis siccus, and the Micrococcus flavus, have colonies quite unlike the meningococcus. But sugar reactions and agglutina- tion tests will have to be applied to microbes from characteristic colonies before a definite diagnosis can be made. The microbe can often be isolated from the urine and blood. The toxin of the microbe is an endo- toxin ; at least, no exotoxin appears to be formed in vitro. Immunity is produced by the formation of coferment or immune-body, which enables the phagocytic cells to ingest and digest the microbe, and of anti-endotoxin, which neutrahses its toxin. Phagocytosis is aided by the agglutinating functions of antibodies. In fact the mechanism of immunity is quite typical. Accompanying and secondary infections are of frequent occurrence, such as diph- theroid bacilli. Gram-positive cocci and pneumo- cocci. Prophylaxis. — Contacts frequently carry the microbe in the nasopharynx and excrete them in their urine in some cases. Many nose washes have been used for these cases ; "2 per cent, benzoyl chloride in liquid paraffin used in an atomiser will probably be found more effective than most. All contacts—at any rate, all in whom the microbe is i88 Nervous System. found — should receive prophylactic inoculation with the particular strain of microbe ; the series 25, 50, 100, 200 million will generally be found effective. Treatment, — The first essential is to reduce at once the tension of the cerebrospinal fluid to normal and then to keep it there. No manometer is neces- sary ; when the fluid from the puncturing cannula drips normally the cannula can be removed, or if serum is being used the serum injected. I have removed as much as 80 c.c. at one time. The serum treatment is that chiefly in vogue. It is usually injected intrathecally and the foot of the bed raised to facilitate its spread upwards. Various reports as to its efficacy have been recorded, giving mortalities varying from 8 — 40 per cent, or more. The serum is evidently useful if it happens to hit off the strain, as is the case with all anti- bacterial sera. Quite as good or better results have been reported from simple lumbar puncture alone, especially when efficiently carried out. In a small series of cases I have recovered five out of six cases with lumbar puncture and vaccine. The case that died had been unconscious for four days before admission. One case that recovered had chronic nephritis with a large amount of albumen in the urine. My practice is to do a lumbar puncture at once and give 2| million of a vaccine made from another case. The patient is watched for any slowing of the pulse ; if this occurs, puncture is at once done again. If there is increase of symptoms after the vaccine the 2| million dose of autogenous vaccine is given after these have passed off. If no increase 189 Therapeutic Immunisation. of symptoms or if improvement has taken place the autogenous vaccine is given thirty-six hours after the first dose. The series 2-|, 5, 7I, 10, 15, 20 is usually sufficient ; sometimes higher doses are neces- sary. Unless the patient is unconscious I much prefer to do the puncture under light general anaesthesia, which prevents shock and relaxes the arching of the back. Acute cerebrospinal meningitis produced by other microbes, such as the pneumococcus, are investi- gated and treated on the same lines. Neuritis. — Inflammation of the nerves produced by microbes, apart from that produced by direct extension, has the same etiology and treatment as other rheumatic conditions, for instance, rheumatism of joints iq^v,). Tetanus is one of the few instances of disease produced solely by an exotoxin, for the toxin- producing microbes appear to be entirely confined to the wound into which the tetanus bacilli or their spores have been introduced. Pathology, — The wound is usually a lacerated one with sloughs and the infection is always mixed, the aerobic microbes producing the anaerobic condi- tions necessary for the development of the tetanus bacillus by absorbing oxygen and distracting the attention of the phagocytes from it. The toxin tetanospasmin has a very strong affinity for nervous tissue and is said to reach the central nervous system by ascending along the nerves serving the infected area. The lesions found post mortem are confined 190 Nervous System. chiefly to the large gangUonic cells of the brain and anterior horns of the spinal chord which show evidences of degeneration when stained. Bacteriology. — In pus the bacillus usually appears as a long slender rod 3 — 4 /x in length and 0*3 — 0-4 fi in breadth. It shows, in the absence of oxygen, slow waving movements; these movements cease when the bacillus develops a spore, as it does sometimes in pus and always in anaerobic cultures. The spores are spherical and terminal. The non-sporing bacillus has numerous lateral flagella. The bacillus is Gram- positive. It grows well on ordinary broth or solid media made with freshly made extract of meat which has not been heated above 100 deg. C. It is strictly anaerobic when grown in pure culture. If other microbes are present, such as the Bacillus subtilis, it will develop under aerobic conditions. The presence of the tetanus bacillus is generally not recognised until the onset of characteristic symptoms infallibly indicate its presence. If it is present in a wound an injection of the pus into a rabbit, guinea-pig or mouse produces the charac- teristic symptoms. It can sometimes be seen in Gram-stained smears of the pus, and grown from this pus developing the characteristic spore on culture. Prophylaxis, — As I have stated, once the toxin becomes attached to the nerve cells it is out of the reach of antitoxin which acts by forming a com- bination with the combining group of the toxin molecule and not by destroying its zymophore 191 Therapeutic Immunisation. group (see p. 19). It is all-important, therefore, to give a patient who has received a gunshot injury or dirty wound a dose of antitoxin of at least 25 c.c. at once and to repeat the dose every seven days until there is no probability of his developing tetanus, i.e., for three or four weeks. This is the usual practice. This measure is usually effective, but there is no reason why a mixed immunity should not be produced by giving a small dose of toxin at the same time. Probably one dose of combined toxin and antitoxin would be effective. The wound should be treated with either iodine in solution or iodoform in ether, since iodine destroys the zymo- phore group of the toxin molecule. Treatment.- — Antitoxin having no effect on toxin already attached to the nerve substance its only use in treatment is to prevent further toxin becoming attached, that is, to neutralise toxin in the circula- tion. Unfortunately, it can neither get through the walls of the capillaries of the brain nor through the secretory cells of the choroid plexus, so as to gain access to the nerve cells, so that the only way to effect this is to inject it into a lateral ventricle after trephining or into the cerebrospinal fluid by lumbar puncture. Ballance's operation devised for the introduction of salvarsanised serum into the lateral ventricle is very neat. A trephine hole is made in the angle between the sagittal and coronal sutures. The dura is incised and turned aside. The hemisphere is gently pulled sideways from the falx cerebri and a small blunt trocar and cannula is pushed through the 192 Nervous System. anterior part of the corpus callosum into the lateral ventricle. Through the cannula the serum is introduced. Generally about 25 c.c. should also be given intravenously and 25 c.c. into the tissues near the wound. Probably the intraventricular method is the only method of any use in fulminating cases. Intensive iodine therapy will probably prove very useful. I think intravenous injections of i grain (64 mg.) of iodoform in i c.c. of pure ether once a day or oftener or 5 c.c. doses of a i per cent, solution of sodium di-iodosalicylate would be well worth trying. It is quite possible that the iodine, which can pass the barrier of the choroid plexus, will neutralise the toxin already attached to the nerve cells. It is absolutely essential to control the spasms by reducing the sensitiveness of the reflex mechanism. Various methods have been used, chloral or morphia by the mouth ; 10 c.c. of a 5 to 25 per cent, solution of magnesium sulphate intrathecally or subcutaneously have been used with success. I have found Hutchings' method of giving 60 grains (4 grammes) of chloretone in warm olive oil by rectum daily, or as often as necessary, very effective. Rabies. — Rabies or hydrophobia is an infection of the central nervous system with a virus intro- duced by bites of infected animals, such as dogs and cats. Pathology and Bacteriology. — The organisms ascend to the brain along the nerves. It is beheved that the 193 ^3 Therapeutic Immunisation. bodies described by Negri, which vary in size from 0*5 — 14 /X, in the cells of Purkinge and the large cells of the cerebral cortex and anterior horns of the spinal cord are the cause of the disease. More recently Noguchi has cultivated similar bodies in vitro and has produced the disease with these cultures in rabbits, guinea-pigs and dogs. They are described as granular nucleated and corpus- cular bodies and very pleomorphic. The smallest size must be capable of passing through a porcelain filter, since filtered suspensions of the brain of infected animals will infect. Leuco- cytes accumulate round the blood-vessels and large motor nerve cells and also round the cells of the sympathetic and cerebrospinal ganglia, in fact, round all the cells that harbour the Negri bodies. It is, of course, of the utmost importance to dis- cover as soon as possible whether or not an animal which has bitten the patient is harbouring the para- site or not. The animal's brain should either be removed at once and placed in 10 per cent, formalin in normal saline or, better, the body decapi- tated, the head packed in ice and despatched to the laboratory. If the brain is allowed to decom- pose at all bodies produced by degeneration may simulate the Negri bodies which are diagnostic. Suspensions of the suspected brain should be in- jected under the dura of rabbits, which will develop the disease in fifteen to twenty days if the material contains the parasite. Prophylaxis, — Since the disease is quite incurable 194 Nervous System. by present methods, once it sets in, prophylaxis is of the first importance. Pasteur found that by passage through about fifty rabbits the virulence of the microbe was so increased that the incubation period was reduced from from fifteen to twenty days to six, but could not be reduced further ; he called this the virus fixe. By keeping the spinal cords of rabbits, inoculated intracerebrally and dead from this virus, in a dry atmosphere the virulence of an extract of them diminished each day until on the fourteenth day it was safe to inoculate a patient ; by giving a series of inoculations of cords kept a shorter time, and therefore more virulent, the patient's immunity was gradually built up, so that he was able to take with impunity an inoculation of a cord of full virulence. Emery gives a typical series : — Day I. — Inoculation with vaccine made by drying the cord for fourteen days. A second injection with a cord treated for ten days. Day 2. — Two injections ; cords dried for eleven and nine days. Day 3. — One injection Day 4. — One injection Day 5. — One injection Day 6. — One injection Day 7. — One injection Day 8. — One injection Day 9. — One injection cord dried for eight days, cord dried for seven days, cord dried for six days, cord dried for five days, cord dried for four days, cord dried for three days, cord dried for two days. Day 10. — One injection ; cord of rabbit which had died the same day and was therefore of full virulence. 195 Therapeutic Immunisation. In severe cases the inoculations are kept up for a longer period. If Noguchi has isolated the causative microbe probably less laborious methods will be devised. The incubation period in man is generally two months or more, so that there is usually plenty of time to kill off the microbe before it reaches the central nervous system. It has been calculated that about 15 per cent, of cases bitten by mad dogs and untreated develop the disease. Thirty thousand odd cases have been treated at the Pasteur Institute with 125 deaths. Anterior Poliomyelitis is an acute infection of the central nervous system produced by an organism which, like that of rabies, is a ' filter passer.' Pathology. — The lesions are those of an acute polio- encephalo-myelitis. The infection begins in the meninges, to which it spreads from the nose through the cribriform plate of the ethmoid along the olfac- tory nerves. Inflammatory changes occur through- out the pia-arachnoid, consisting of perivascular small round-celled infiltration, vascular dilatation, oedema and small haemorrhages. These changes spread inwards along the pial septa. Inflammation is especially severe in the anterior cornua, where the pyramidal cells are especially affected. At first the cerebrospinal fluid contains considerable numbers of polynuclear leucocytes, later mono- nuclear cells predominate. This fluid is said not to be infective, in the majority of cases, in animal experiment. 196 Nervous System. Bacteriology. — In 1913 Flexner and Noguchi cultivated and demonstrated microscopically a small filterable micro-organism with which they produced poliomyelitis in monkeys. They isolated from throats, tonsils, abscesses in tonsils and from the central nervous system a peculiar streptococcus. Paralysis has been produced in various animals by intravenous and intracerebral injection of cultures of this organism and lesions of the grey matter of their central nervous system have been demon- strated. The microbe is very pleomorphic and its size appears to depend on the medium on which it is grown, even after passage through a filter. It is probable tha,t in the environment of the central nervous system the streptococcus takes the form of the ' filter passer. ' This influence of environment on morphology is not peculiar to this microbe, but can be demonstrated on many microbes, even the stolid Staphylococcus aureus. Prophylaxis and Treatment. — So far as T know little or no attempt has been made to produce active or passive immunity for prophylactic purposes. One attack of the disease, however abortive, protects, and the serum of such persons given intravenously, intrathecally, or subcutaneously in doses of 5 — 20 c.c. has been used with encouraging results in some cases. Disseminated Sclerosis. — One case of this con- dition has markedly improved with inoculations of a vaccine made from the staphylococci he was excreting from his urine plus a vaccine (streptococci) made from his post-nasal catarrh and B, coli vaccine 197 Therapeutic Immunisation. from his faeces. Lyon Smith and Grainger Stewart record a successful case where the staphylococcus was isolated from the cerebrospinal fluid. The Eye. The extraocular infections of the eye, that is, infections of the eyelids, conjunctiva and cornea, respond readily to specific therapy. As can be easily imagined the intraocular infections, unless perhaps recent wound infections, are much less satis- factory, since even if the infection is cleared up the eye is often permanently damaged. However, a great deal can be done to help infections after operation. Eyelids. — Most of the infections of the eyelids are staphylococcal in origin ; they are eczema, marginal blepharitis and stye. Other infections associated with special forms of conjunctivitis can, of course, occur. Eczema of the margins of the lids can be caused by other primary irritants than microbes, such as irritating fumes and discharges, but staphylococci generally invade the tissues whose resistance is thus lowered and form part of a vicious circle. In other cases the staphylococcal infection is primary. A further stage, known clinically as marginal blepha- ritis, is the infection of the follicles of the eyelashes, the hair being surrounded with pus, the cuticle between the lashes is cast off and crusts form, leaving a moist red granular surface (granulation tissue) when removed. The hair follicles may be destroyed and the lashes cast off. In other cases the formation of fibrous tissue distorts the follicles and lashes and leads to lacrimation. 198 Eye. Styes are furuncles, the infection starting in the glands of Moll, the hair follicles or the Meibomian glands. In the latter the etiology may be similar to that of acne, since the primary infection may be due to the acne bacillus whose natural habitat is the sebaceous glands. Treatment, — The vaccine treatment and dosage of the vaccines is exactly similar to that already described for eczema, sycosis and acne [q.v., p. i66). Conjunctiva and Cornea. — Ophthalmia is so easily treated by local antiseptic methods that I suppose the majority of eye surgeons will not think any further methods necessary. However, no one will deny that in some acute and chronic infections which may lead to opacities in the cornea or to its perforation or even sloughing every weapon available should be used. Pathology. — There is nothing peculiar about the pathological histology of the conjunctiva. The microbial toxins may produce an effect varying from a slight hyperaemia with a small amount of sero- purulent discharge to sloughing of the conjunctiva and cornea and destruction of the eyeball. Diph- theria bacilli, as elsewhere, produce a membranous slough. It is not within the scope of this book to go into the pathology of the many clinical forms of ulcer of the cornea ; the general mechanism of their produc- tion is as follows : The corneal tissue is invaded from the surface by microbes ; a collection of leucocytes occurs at the site and the superficial tissues slough. When healing takes place the trans- 199 Therapeutic Immunisation. lucent corneal tissues are replaced by opaque fibrous tissue. Bacteriology. — ^Acute epidemic catarrhal oph- thalmia is produced most commonly by the Koch- Weeks bacillus, less commonly by the Morax- Axenfeld bacillus or by such microbes as the pneu- mococcus. Very many other microbes produce opththalmia. The gonococcus is quite the most important, for it produces acute suppurative in- flammation which frequently leads to permanent blindness. Pollock gives the following list of microbial findings in 361 cases : — Of 236 cases of acute mucopurulent catarrh 177 contained Koch- Weeks, 9 ,, Morax-Axenfeld, 6 pneumococci, 2 gonococci, I gonococci and Koch- Weeks, 6 staphylococci, 4 „ indeterminate microbes. 28 were negative. Of 69 cases of subacute catarrh 7 contained Koch- Weeks, 51 ,, Morax-Axenfeld, 3 „ undiagnosed microbes. 8 were negative. Of 10 cases of purulent catarrh 3 contained Koch- Weeks, I ,, Koch- Weeks and B. subtilis, I pneumococci, 5 „ gonococci. 200 Eye. Of i8 cases of ophthalmia 2 contained Koch- Weeks bacilli. 7 pneumococci, 10 gonococci (pure), I „ gonococci and streptococci. I gonococci and Koch-Weeks, I gonococci and pneumococci, I was negative. Two cases of membranous conjunctivitis con- tained staphylococci. Sixteen cases of phlyctenular conjunctivitis were negative. Of 10 cases of catarrh complicated with ble- pharitis 2 contained Morax-Axenfeld bacilli, 5 staphylococci, 2 staphylococci and streptococci. I was negative. So that apart from the specific microbes the Koch- Weeks and Morax-Axenfeld bacilli the most common enemies are the gonococcus, pneumococcus, staphylococcus and streptococcus. A diphtheroid bacillus, the B. xerosis, is a common inhabitant of the conjunctival sac, as is also the Staphylococcus epidermidis. Treatment. — The infections with the Koch- Weeks and Morax-Axenfeld bacilli appear to be so amenable to antiseptic treatment that no special means need be employed in their treatment. In acute suppurative inflammation serum, if available, or vaccine should be used at once. The only sera likely to be effective are anti-pneumonic or 201 Therapeutic Immunisation. anti-streptococcic, and they can be given both sub- cutaneously and also instilled into the conjunctival sac. Pending the making of an autogenous vaccine stock vaccine, if available, should be used. The commercial gonococcic and pneumococcic vaccines are of very weak toxicity and comparatively large doses can be used ; lo million of either may be given as an initial dose to an infant and 50 million to an adult. If these vaccines are made from the patient or from a recently isolated microbe i million is quite a large enough initial dose for an infant and 2 J million for an adult, and the progression is 5. 7h io> ^5> 20, 30, 50, 75, 100, 150, 200 million. Commercial streptococcus vaccine is more effi- cient and the smaller doses mentioned should be used. The doses of staphylococcus vaccine may be 50 million in children and acute cases, 100 million in adults and chronic cases. In chronic cases very large doses may have to be reached before complete success is attained. In one case of trachoma with pannus and a secondary infection with the Staphylococcus aureus a dose of 10,000 million of a vaccine of this microbe was reached. This case had resisted all local treatment and the man was unable to read anything but large print, and that only with one eye. The condition cleared up in a most satisfactory manner, leaving nearly perfect vision in one eye and only a slight opacity in the other. Intraocular Infections occur from wounds, 202 Eye. either perforation of a corneal ulcer, operation in- cisions or accident, or through the blood-stream. Bacteriology. — According to Axenfeld the pneu- mococcus is the most frequent operation wound infection, but any of the pathogenic microbes may be the cause, especially those infecting the nose and 'mouth and, not uncommonly, the saprophytic B. xerosis and the Staphylococcus epidermidis become pathogenic. In infections produced by accident other, usually saprophytic, microbes, such as the B, subtilis, when introduced into the vitreous become pathogenic. In such cases the only thing to do is to remove the eye. In blood-borne infections a focus of infection will always be found elsewhere. Iridocyclitis is most common in rheumatic conditions and the commonest cause, therefore, streptococci. I have treated a case of chronic iridocyclitis with a vaccine made from a diphtheroid bacillus isolated in pure culture from a chronic nasopharyngitis ; marked focal reactions occurred so that there can be no doubt that this was the infecting microbe. Quite as commonly, the infecting microbe can be isolated from pyorrhoea alveolaris. Treatment. — In infected operation wounds the microbe can be isolated from them. Although I have no personal experience, I have no doubt vaccines, if given according to the principles already laid down in this book, will be of very great help in these very anxious cases. The treatment of rheu- matic infections need not be repeated ; they have already been treated of (see p. 156). 203 Therapeutic Immunisation. The Ear. From the point of view of local therapy the infections of the Eustachian tube and middle ear are very unsatisfactory owing to their inaccessible- ness ; this is especially so when the mastoid cells and labyrinth become involved, when recourse must be had to operation if involvement of the meninges or lateral sinus is to be prevented. Pathology. — The infection is practically always a sequel to that of the nasopharynx. The Eustachian tube is first involved, its mucous membrane becoming swollen owing to serocellular infiltration of its tissues with, at first, a serous dis- charge on the surface which becomes mucopurulent. It soon becomes obstructed, the closure taking place first at its narrowest part, the isthmus. The inflam- mation may then spread to the tympanum, the surface spread being probably helped by the closure of the tube, absorption of the air producing a negative pressure tending to the aspiration of infected dis- charge into the cavity and to retraction of the drum. According to the kind of microbe or the quality of its toxins the inflammation may be catarrhal or suppurative. The changes in the lining membrane of the tympanum are similar to those in the Eustachian tube, the muco-sero-cellular secretion poured out on the surface fills up the cavity, the cells of the mastoid and the pockets of mucous membrane in the attic. The membrana tympani is involved and the inflammatory changes spread along the walls of the 204 Ear. external auditory meatus, where often bullae are formed. If the microbial toxins are pyogenic the effusion rapidly becomes purulent. As a rule per- foration and discharge takes place through the mem- brana fiaccida. In the worst cases the drum becomes totally destroyed and necrosis of the ossicles takes place and acute osteitis and necrosis of the mastoid. Involvement of the tegmen tympani leads to abscess in the brain ; and of the wall of the lateral sinus to septic thrombosis and pyaemia. Non-suppurative inflammation may be so subacute from the start as to attract little attention until gradually increasing deafness is noticed. Bacteriology. — The infection is very commonly a mixed one. By far the most common primary infec- tion is the streptococcus ; this is not surprising, as it is the most common cause of post-nasal catarrh. In scarlet fever the condition may be caused by the diplo-streptococcus, the probable cause of that disease, or by the ordinary Streptococcus brevis or both. A combination of staphylococcus and strepto- coccus is common, as is also the pneumococcus and pneumobacillus. Other Gram-negative bacilli of various kinds are not uncommon, e.g., the ozoena bacillus and the B. pyocyaneus. Various Gram- positive and diphtheroid bacilli are not infrequently found and microbes of the Micrococcus catarrhalis group. Except during epidemics of them the influenza and whooping-cough bacilli are uncommon. The causative microbes can be obtained from the discharge via the perforation if it is present or by incision if bulging of the membrane shows that pus is 205 Therapeutic Immunisation. present. In chronic cases the microbes isolated from the discharge in the nasopharynx may be assumed to be the cause of the changes in the tympanum. Furunculosis in the external meatus is nearly always staphylococcal, and eczema of it, if secondary to middle ear disease, is caused by the microbes producing this, plus staphylococci as a complicating infection. Prophylaxis and Treatment. — Middle ear disease, following as it does on acute and chronic post-nasal infection, is an additional and potent reason for not allowing post-nasal catarrh to continue. As I have already said, a few injections of vaccine of the causative microbes in the acute stages will usually insure this. In such diseases as scarlet fever specific therapy with streptococcal serum or vaccine or both will prevent these complications. If middle ear suppuration occurs the discharge should be liberated at once by incision and a vaccine prepared. It is remarkable how rapidly, in the acute stages, suppuration in the middle ear can be controlled, provided the vaccine contains all the causative microbes. The dosage is the same as for post-nasal catarrh and has already been described (see pp. 113, 114). 206 CHAPTER XII. INFECTIONS PRODUCED BY STREPTOTHRICES. Tubercular Infections. — The tubercular infec- tions of the different tissues are being considered together, since the essential changes and treatment are similar. Tubercular disease of the lungs is too big and important a subject for a single chapter and has been dealt with in a separate book.^ Pathology. — The effect of streptothrices on the tissues is to produce granulomata, the cells of the tissue being destroyed and replaced by masses of cells newly formed under the stimulus of the microbe. The miliary tubercle is the primary formation. It consists of a central mass of epithelioid cells pro- duced by the division of the endothelial cells of the part and also, in the lungs, by division of the alveolar epithelium. The central mass of cells becomes surrounded by small round cells produced by reaction of the tissues. If the condition is very acute and generalised the lesion does not get beyond this stage owing to the death of the patient, the tubercle being about the size of a millet seed. If the disease is more chronic, giant cells form ; they arise by the nucleus of an epithelioid cell, which has ingested tubercle bacilli, dividing and sub- dividing without division of the protoplasm. As the mass gets larger the toxins of the microbe and 1 Pulmonary Tuberculosis." J. & A- Churchill. 207 Therapeutic Immunisation. the cutting off of nutrition produce necrosis of a peculiar kind, the cells losing their identity and being converted into a uniform cheesy mass. This casea- tion spreads outwards with the invasion of the tissues by the infection, so that by this invasion and the coalescence of neighbouring areas, large masses of caseous material may form. In hard tissues such as bone, masses of the bone may die undestroyed by the tubercle bacillus, but killed by the cutting off its blood supply. In this way sequestra form. If the patient's immunising mechanism responds sufficiently the disease is got rid of, either by its isolation due to the reaction of the tissues producing dense masses of fibrous tissue which gradually contracts, while lime salts may be laid down in the caseous mass, or, more commonly, the caseous mass softens down into tubercular pus, a thick creamy fluid characterised by the absence of polynuclear pus cells, which burrows its way along a path of least resistance to the surface by a process of pressure and colliquative necrosis. A sinus is thus formed, which commonly becomes invaded by pyogenic microbes. This is always the case when the disease is superficial and the necrosis produces ulceration as in lupus and in the intestine, where the process starts in the Peyer's patches. A mixed infection is the rule rather than the exception in the lungs and also in tubercular glands in the neck, where the tonsils are the source of infection, as a rule. In the case of bones, if the infection is overcome by suitable treatment, for instance, in cancellous tissue, the diseased bone may be absorbed and new bone laid 208 Infections Produced by Streptothrices. down so that the bone is reconstituted. If a large mass of bone is destroyed, for instance, the whole of the shaft of a long bone, it can be removed and, if the periosteum is intact and a suitable skeleton provided, a new functionally perfect bone is pro- duced. The cellular changes described have as their object the isolation of the infected area by reaction of the tissues and the ingestion and digestion of the microbe by the epithelioid cells. The microbe pro- duces no chemiotactic substance for the polynuclear leucocytes, which do not arrive on the scene unless other microbes are present, when they also ingest tubercle bacilli. The efficiency of the phagocytosis is dependent on the formation of immune-body and antitoxins by the tissues in general. Bacteriology. — ^The tubercle bacilli as they occur in the tissues are 2-5 /x in length and about 0-3 /x in thickness. They are straight or slightly curved and often exhibit unstained areas — polar staining. They are, as a rule, acid-fast, not being decolorised by acid when stained with carbol fuchsin, but some- times, especially when young, they are not acid-fast, but can be demonstrated by a modification of Gram's method. The bacillus can split up in the tissues into minute granules, acid-fast or non-acid-fast, which are infective. By injecting tubercle bacilli into a solid organ like the kidney, or under the dura mater of an animal, spherical masses may form, consisting of radiating filaments with clubbed ends. There are several strains of tubercle bacilli, viz., the human, bovine, and avian types. In lupus, which can be produced by either the human or T.I. 209 ^4 Therapeutic Immunisation. bovine type, the infection is of low virulence. A large proportion of the cases of tuberculosis in children are caused by the bovine type, the infection being conveyed in milk. Most cases of pulmonary tuberculosis and of ' surgical ' tuberculosis in adults are produced by the human type. Both types are equally infective to man. Methods of Invasion. — There are two vehicles for tubercle bacilli — uncooked food and air. Milk and butter are the principal food vehicles of the bovine type. Since the human type bacillus does not cause disease in the cow all cases produced by milk are bovine in origin. The infection is conveyed by the air in the form of atomised sputum or dust. What- ever the method of infection, the bacilli are conveyed by leucocytes through the mucous membrane, especially at sites of collections of lymphoid cells, such as the tonsils, Peyer's patches, lymphoid areas in the bronchi and through the stomata of the pulmo- nary alveoli, into the lymphatic system. They may be destroyed at once or be isolated in the lymph glands, where they set up a chronic infection, or the infection in these glands may act as a source of slow general infection of the blood stream. Blocking of glands may produce a reversal of the lymph stream of a particular area, and the infection may spread peripherally, producing disease, for instance, in the lungs and pleura in the case of the glands of the hilus, in the peritoneum or intestine in the case of the abdominal glands. If the infection is severe the lymphoid entrance gate becomes markedly infected and ulcerates, the ulceration being increased by 210 Infections Produced by Streptothrices. invasion with other microbes, especially the B. coli in the intestine. If a broken-down gland ulcerates into a vein acute miliary tuberculosis results. Evidently an infection may lurk for years in the lymphatic gland traps, in patients whose immunity is not just sufficient to kill them off entirely, until invasion by other microbes or other cause of lowering resistance, e.g,, psycho- logical, alcoholic or environmental, determines its spread. The tubercle bacillus can be grown in pure culture by two methods. The tissue or discharge containing it can be treated with antiformin (equal parts of liq. sodae chlorinatae B.P. and 15 per cent, caustic soda), which destroys rapidly all other microbes (except spores) but the tubercle bacillus and liquefies the material, which, after this treatment for varying times up to half an hour, is centrifuged and cultures made from the deposit. Or the infected material can be broken up in water and injected into a rabbit or guinea-pig, which does the killing off of the other microbes. An infected gland is then removed aseptically, broken up and inoculated on egg slopes or other suitable media. The tubercle bacillus does not grow well on ordinary -f 10 agar, but it does much better if fresh human blood is added. Both human and bovine bacilli grow excellently on Dorset's egg medium, the addition of glycerine to which is said to increase the growth of the human type and inhibit the growth of the bovine type. Both types grow quite well on plain egg medium. If the medium 211 '4-^ Therapeutic Immunisation. is to be used for making tuberculin, fresh human blood should be added. The microbe grows well on serum media and glycerine veal broth. Further details are outside the scope of this book. Prophylaxis. — The tubercle bacillus is so universally present that it is practically impossible to prevent infection, as the accompanying table shows. Incidence of Tuberculosis in Vienna. Diagnosed by : — Autopsy. Tuberculin Reactions. Lethal; Non- lethal. Non- lethal only. Cutaneous. Cutaneous and In- jectional. Investigator : — Ghon. Ghon. V. Pirquet. Gang- hofner. Hamburger and Monti. Hamburger and Monti. 2nd year of life 3rd — 4th years 5th-^6th yth — loth nth — 14th Per cent. 40 60 56 63 70 Per cent. 17 30 34 35 53 Per cent. 2 13 17 35 55 Per cent. 12 27 47 57 70 Per cent. 9 23 36 47 51 Per cent. 9 27 51 71 94 The large majority of cases that get infected overcome the disease, their immunising mechanism being normal. Those whose resistance is subnormal, however, develop the disease. The lowering of their resistance may be due to — 1. Bad hygienic surroundings. 2. Infection with other microbes. , 3. Inheritance of a low resistance. 4. The overcoming of a normal resistance by a virulent or continuous infection. I. The effect of bad environment is well illustrated 212 Infections Produced by Streptothrices. by figures of tuberculosis mortality among the different classes in the Dublin registration area for Professional and independent classes 1-84 per 1,000 Middle class . . . .2-18 Artisans and shop keepers . • 3'ii General service classes . . . 3-61 It is often argued that improvement of hygienic surroundings — good housing, food, etc. — is all that is necessary to stamp out the disease. That a good environment is essential is obvious from these figures. And yet, since we may take it that the middle class enjoy a sufficiently good environment, and usually die at home, while their death-rate from the disease is 1-92 per 1,000, it is clear that something else is necessary. 2. Infections with other microbes often lower resistance — measles, whooping-cough, and so on. In the alimentary canal when sputum is swallowed containing a mixture of tubercle bacilli and virulent catarrh microbes, these latter are potent factors in lowering the resistance of the intestine to the tubercle bacillus. 3. Inherited Low Resistance. As I have written elsewhere (''Pulmonary Tuberculosis"), it seems to me unreasonable to suppose that germ cells inhabiting a person poisoned with tubercular toxin should not participate in the poisoning effect and hand on the lowered resistance, especially if the infected person is the mother. Karl Pearson has investigaged the matter statistically, and has come to the conclusion that this supposition is true. 213 Therapeutic Immunisation. 4. A normal resistance may be overcome by a massive or continuous infection with virulent microbes. The most common source of this infection in infants and children is infected milk. A large pro- portion of milch cows supplying milk to cities have been found to be infected, as many as nine out of thirty-five in one case, and these without obvious disease of their udders. A properly managed municipal milk supply from immunised cows is the only sound solution of the milk difficulty ; in no other way can rich or poor be assured of a sound supply at a reasonable figure. There is only one certain method of bringing up a low resistance to a microbe to normal or of increasing a normal resistance, and that is the production of specific antibodies or of a mechanism facile in the production of these antibodies in the individual by inoculating him with the toxin or vaccine of that microbe. In the case of a universal infection like tuberculosis it is the one measure that will protect when the constitutional resistance is lowered by the various environmental and inherited causes of low resistance. I give the following series of doses of a solution of the tubercle bacillus, human or bovine type, H.T.S. orB.T.S. (see p. 217), in benzoyl chloride, to an infant of three months or more at weekly intervals : -oooooi mg., -ooooi mg., -oooi mg., •001 mg. For older children, unless they are sus- pected of being tubercular, when the first dose should be -ooooooi mg., the series may be -oooooi mg., -OOOOI mg., -0001 mg., -ooi mg., and 'Oi mg. 214 Infections Produced by Streptothrices. For adults an additional dose of O'l mg. may be added. Diagnosis. — There is an additional advantage in doing this preventive inoculation, for if the patient is tubercular a reaction will occur after one of the doses, and a proper course of treatment can be instituted while the disease is easily curable. In this way tuberculosis of bones, joints, kidneys and other organs can be discovered in its early stages, by the occurrence of focal reactions, and recovery thus assured with the minimum of damage. The doses should be -ooooooi mg., -oooooi mg., •poooi mg., -0001 mg. H.T.S. or B.T.S. If no reaction occurs after any of them the lesion is most unlikely to be tubercular. It must not be forgotten that the relief of focal symptoms is just as significant as their increase for diagnostic purposes. If tubercle solution is not available A.T. (old tuberculin) may be used; the doses should be o-i c.mm., o-2 c.mm., 0*4 c.mm. and i c.mm. The intervals between the doses should be forty-eight hours, as sometimes the reaction does not come on for twenty-four to thirty- six hours. The inoculations should be given sub- cutaneously, care being taken that the needle is not in a vein before injecting, and that it is not given into an area, the lymphatics of which drain into glands which may possibly be infected, that is, they should be given into an area as far from the lesion as possible. Treatment. — The treatment of chronic tuber- culosis of the lungr, except before the ' open ' stage, by tuberculin alone has been a failure because the 215 Therapeutic Immunisation. infection is nearly always a mixed one. A similar failure may be expected in tuberculosis of other tissues under similar conditions. If a tubercular abscess has burst on the surface and the sinus becomes infected the secondary infection must be cleared up first before starting tuberculin. Some- times, but not often, the tubercular infection is secondary to chronic infections with other microbes, such as the diplostreptococci, the common primary cause of rheumatism. Any pyogenic microbe may be the secondary invader, the most common being staphylococci, streptococci or B. coli. As usual the initial dose of staphylococci may be 25 to 100, according to the age and condition of the patient, and the series 25, 50, 100, 200, 400, 600, 800, 1,000 million, and higher if necessary ; that of the other microbes 2 J million, and the series 2^, 5, 7|, 10, 15, 20 million, and so on. Especial care should be taken if the secondary infec- tion is B. pyocyaneus, a safe series, such as i, 2, 4, 6, 8, 10, etc., being necessary, as this microbe is frequently exceedingly poisonous. If the tubercle infection is closed, or if there is no evidence of secondary infection of the sinus, treat- ment with tubercle bacillus antigen may be begun at once. These tubercle bacillus antigens or tuber- culins are of many kinds and of varying degrees of efficiency. Of all the usually used tuberculins Koch's old tuberculin (A.T.), which is a concen- trated filtrate of a glycerine-veal-broth culture, is as good as any. There are many others produced by Koch, such as A.F. or albumose-free tuberculin, 216 Infections Produced by Streptothrices. T.R., an extract of the ground-up bacilli, T.O., a by-product of the manufacture of T.R. and B.E. or bacillary suspension. Corresponding preparations of the bovine type are also used, called P.A.T., P.T.R., P.T.O., P.B.E. One often finds that when the human type gives too much reaction the bovine type will not, and vice versa. The initial doses of A.T., A.F. and P.T.O. are the same, varying, according to the age and condition of the case, from •001 c.mm. to -oi c.mm. The initial dose of T.R. should not be larger than -oooi. Although it is not a mathematical progression I find the series i, 2, 4, 6, 8, 10, e.g., -01, -02, -04, -06, -08, -I, answers all practical purposes and is safe. If the patient is not having marked reactions one can shorten the course by omitting the 6's and often the I's, skip- ping, for instance, from -04 to -08 and from this to -2 in the above example. However, it generally pays to go slowly and not to risk undue reactions. I have never found it necessary to attain doses higher than 10 c.mm. of any of the above prepara- tions. The intervals between the doses depend entirely on reactions. If there is no apparent reaction, focal or general, the next dose may be given in forty- eight hours, that is, with one clear day's interval. If there is a reaction three clear days should be left after all signs of it have disappeared and then the next dose given, or if it has been severe the last dose repeated. If the patient gets continuous unpleasant reactions with one type of tuberculin it is well to change to the other. 217 Therapeutic Immunisation. None of these tuberculins are, in my experience, as good antigens as the benzoyl chloride solutions, which I have already mentioned. These appear to me to be more likely to have all the essential anti- genic substances present, since they are solutions of living tubercle bacilli, the waxy constituent of which is soluble in benzoyl chloride, but not in water. It might be thought that the endotoxin would be destroyed by the solvent, but the success of the product clinically would point to this not being the case. The initial dose of these is 'ooooooi mg. or 'Oooooi mg., according to the age and condi- tion of the patient, and the progression -000002, •000004, -000006, -000008, -ooooi, and so on, up to •01 mg., or occasionally o-i mg. The dilutions are made in liquid paraffin containing 2 per cent, of benzoyl chloride. As in the case of the other tuberculins, it is often possible to skip the 6's and sometimes the I's. The directions for intervals between doses are the same as for the other tuberculins. A combination of iodine therapy and immuno- therapy, as in other cases, gives the best results. Either iodoform intravenously in ether or the iodine-menthol-radium compound act well. An excellent way of exhibiting iodine therapy in children, especially in tubercular peritonitis, is to rub an amount of ung. iodoformi B.P., the size of a pea, daily, into the skin of the abdomen. Of course every adjuvant measure should also be used, e.g., abscesses drained, sequestra removed, joints immobilised, and so on. 218 Infections Produced by Streptothrices. Actinomycosis. — The ray fungus also produces a granuloma. Pathology, — The most common primary site of infection is the jaw, where a subperiosteal collection of cells forms, which may be mistaken for a sarcoma until suppuration occurs. These epithelioid cells may fuse to form giant cells and are phagocytic. In the pus the little yellow masses, 0-5 — 2 mm. in size, of the fungus are seen. Any organ of the body may become infected, especially the lungs, in which the physical signs and symptoms resemble those of tuberculosis. The lesions nearly always become secondarily infected. Bacteriology, — There are several species of actino- myces which infect man, the most common is the Actinomyces {Discomyces) bovis. The above-men- tioned masses consist of a central mass of segmented filaments (mycelium), the terminal radiating seg- ments of which are club-shaped. The filaments measure about 10 — 12 fi long and the clubs 20 — 30 fi long by 8 — 10 broad. The filaments are Gram- positive and acid-fast, but more easily decolorised than the tubercle bacillus. The clubs are decolorised in both methods. The organism is best isolated by sowing the yellow granules on gelatine plates after thorough washing in sterile waten The granules that do not become surrounded by a halo of other microbes are then picked off and sewn on serum or glycerine-agar slopes. The colonies are yellowish-white, dry, firm and wrinkled, and soon become confluent. Treatment, — Vaccine therapy has proved to be by 219 Therapeutic Immunisation. far the most successful method of treatment. It may be usefully combined with iodine therapy. The vaccine is made by breaking up the masses picked out of the pus and washed, or the growth on the culture, and counting the fragments, taking a standard length. The initial dose is 5 million frag- ments, and the dose should be increased steadily until cure is attained. Vaccines of the secondary infections, if present, should be used at the same time. Leprosy. — Some successful cases of this disease treated with vaccines of Kedrowski's bacillus have been recorded. I have obtained focal and general reactions in ten or more cases, with a vaccine of a non-acid-fast diphtheroid bacillus isolated from lepra modules ; but the results so far are not sufficiently good to warrant further description at present. 220 INDEX. Acidosis, 40, 152 Acne, 166, 167 Actinomycosis, 219 Adenoids, 114 Agglutinins, 42 Agglutinoids, 43 Aggressins, 46 Alexin, 30 Amboceptor, 30 Anaphylaxis, 47 Andrews, 27 Anterior poliomyelitis, 196 Anthrax, 164, 165 Antiformin, 211 Antistaphylococcic serum, 36 Antistreptococcic serum, 36 Antitoxic sera, 20 Antitoxins, 19, 20, 65 Antitrypsin, 11, 19 Appendicitis, 97 Arrhenius and Madsen, 25 Arteriosclerosis, 178 Arthritis, 147, 152 Asthma, 115 B. aerobicus sepis, 159 B. cholercB, 29, 76, 77 B. coli, 7, 85, 98, 102, III, 123, 130, 132, 141, 159 B. diphtheric^, 23, 104 B. enteritidis, 78 B. fusiformis, 81, 82, 116 B, influenzcs, iii B. Melitensis, 174, 175 B. perfringens, 158 B. pertussis, 111, 114 B. pestis, 9, 183 B. proteus, 171 B. pyocyaneus, 78,98, 1 11, 159, 205 B. suhtilis, 191 B. xerosis, 201, 203 Bacillus of malignant oedema, 158 Bactericidal substances, 34, 65 Bacteriolysis, 29, 65 Bacteriotropin, 37 Bail, 46 Ballance, 192 Beattie, 150 Bile ducts, 95 Blitz, 26 Blood vessels, 178 Bordet, 26, 30, 32 Bright's disease, 125 Calmette's conjunctival re- action, 51 Chantemesse, 18 Chloramine T, 143, 149 Cholera, 29, 76, 77 Cimex lectularius, 181 Coferment, 33 Colitis, mucous, 10 1 Colon, 99 Comedones, 166 Complement, 26, 30, 32, 34 Complementoid, 32 Compound fractures, 157 Conjunctiva, 199 Connor, 185 Cornea, 199 Cruickshank, 186 Cystitis, 132 Diabetes, 40 Di-iodosalicylic acid, 122, 143, 149, 152, 161 Diphtheria, 23, 103, 104, 105 Diphtheroid bacilH, 112, 185, 205 Diplococcus intracellularis, i8y Diplococcus mucosus, no 22X Index. Diplococcus pharyngis siccus, no Diplococcus rheumaticus, 1 50 Disseminated sclerosis, 197 Douglas, 35, 41, 141 Duodenum, 88 Dysentery, 78, 80 Ecthyma, 170 Eczema, 170, 198, 206 Emery, 195 Empyema of pleura, 123 Endocarditis, 177 Endometritis, 140 Epididymis, 135 Erysipelas, 163 Eusol, 143, 149 Eustachian tube, 204 Eyelids, 198 Fallopian tubes, 145 Ferment, 32 Fibrositis, 157 Fischer, 14 Flexner, 197 French, 151 Furunculosis, 168, 206 GALL-bladder, 95 Gallstones, 96 Gastric ulcer, 87 Gastritis, 84 (^-Glucose, 13 /-Glucose, 13 Gonococcus, 130, 132, 135, 200 vaccine, 138 Gonorrhoea, in male, 134 in female, 139 Gout, 40, 152 HiEMOLYSis, 30 Haffkine's cholera vaccine, 9, 77 Haffkine's plague propnylac- tic, 9, 184 Hay fever, 115 Immune-body, 21, 30, 31 Immunity, acquired, 8 active and passive, 8, 54 definition of, i mixed, 10, 23 natural, 7 Impetigo, 170 Intra-ocular infections, 202 Invertase, 14 Iridocyclitis, 203 Jaundice, 95 Kedrowski, 220 Koch-Weeks bacillus, 200 Kraus' phenomenon, 44 Labyrinth, 204 Leishman, 35 Leprosy, 220 Liver, 93, 94 Lungs, 117 Lustig, 183 Lymphadenoma, 185 Lymphatic glands, 181 Marginal blepharitis, 198 Mastoid, 204 Mediterranean fever, 173 Meningitis, 186 Meningococcus, 187, 189 Metchnikoff, 18, 27, 34 Microbes, virulence of, 5, 6 Micrococcus catarrhalis, 81, 109, 116, 141, 188 Micrococcus fiavus, no, 188 Micrococcus paraietragenus, no Micrococcus tetragenus, no Middle ear, 204 Milk-souring microbes, 3 Morax-Axenfeld bacillus, 200 Morgan's No. i bacillus, 78 Moro, 52 Mucous colitis, 10 1 Muir, 33 Myocarditis, 176 222 Index. Nasal catarrh, io6 Negative phase, lo, 21 Negri, 194 Nephritis, 125, 126 Neufeld, 37 Neuritis, 190 Nitrifying microbes, 2 Noguchi, 196, 197 Opotherapy, 70 Opsonic index, 36, 59 Opsonins, 25, 35, 64 Osteomyelitis, 146 Ovaries, 145 Ozaena bacillus, 112, 205 Pancreas, 89 Parasitic microbes, 3 Paratyphoid, 72, 73, 75, 124, 130, 132 Pasteur, 165, 195 Pavlow, 16 Pemphigus, 170 Pericarditis, 175 Pfeiffer, 29, 77 Phagocjrtosis, 34 von Pirquet, 52 Plague, 181 Pleurisy, 122 Pneumobacillus of Friedlander, 81, no, 117, 205 Pneumococcus, 98, 108, 116, 117, 120 — 123, 200, 205 Pneumonia, 117, 122 Positive phase, 21 Poynton and Payne, 150 Precipitins, 44 Prototoxoid, 24 Pyorrhoea alveolaris, 81 Saprophytic microbes, 2 Schizomycetes, 2 Sclavo, 165 Seborrhoea, 166 Sera, antitoxic, 20 Shennan, 141 Side-chain theory, 15, 16, 19 Spleno-meduUary leucaemia, 39 Staphylococcus, 82, 98, 102, 108, 116, 130, 132, 141, 146, 159, 167 — 171, 197, 198, 200, 205 Starling, 99 Streptococcus, 85, 98, 102, 109, 116, 130, 132, 141, 146, 159, 163, 170, 171, 175, 205 Stye, 199 Substance sensibilisatrice, 30 Sycosis, 168 Symbiotic microbes, 3 Szendeffy, 62 Testis, 135, 144 Tetanolysin, 15 Tetanospasmin, 12, 14, 15 Tetanus, 190 — 192 Tonsillitis, 116 Toxins, 4, 12 endotoxins, 17 exotoxins, 12 haptophore group of, 15 taxophore ( = zymophore) group of, 15, 19 Toxoids (= zymoids), 16, 23 Toxon, 24 Tuberculins, 214 et seq. Tuberculosis, 207, 209 Typhoid, antiserum, 76 bacillus, 73, 98, 123, 130, 132 fever, 72 toxin, 18, 23 vaccine, 74 Rabies, 193 Reactions, 21, 58, 59, 61 Receptors, 16 Rheumatism, 40, 149 Rheumatoid arthritis, 152 Richet, 47 Roland, 183 223 Undulant fever, 173 Urethritis, 134 Urine, reaction of, 133 Index. Vaccines, 54, 68, 69 Weichselbaum, 187 Whooping-cough, 114 Widal reaction, 43 Wounds, 157 Wright and Douglas, 35, 41 Xenopsyll us(^ — Pulex cheopis) , 181 Yersin, 183 Zones of inhibition, 43 THE WHITEFRIARS PRESS, LTD., LONDON AND TONBRIDGK.