A 19-year-old college student is seen in your office for cough. She recently joined the intramural soccer team and has noticed cough during her practices and matches. The cough generally appears 1-2 hours into her exertional activities, but it has occasionally occurred suddenly after she has been at rest after exertional activities. The cough is non-productive and associated with wheezing, especially when the weather outside is colder. She denies having chest pain, abdominal pain, or symptoms at night. She has no allergies and takes no medications.
Previously her primary care physician checked spirometry (which was normal) and prescribed an inhaler for her to use prior to exertion and sports activities. She used it only a few times and doesn’t recall if it was effective.
On examination, her vital signs are within normal limits. Her cardiovascular and abdominal examinations are normal. Her pulmonary examination reveals good air movement, no crackles, wheezes, or other abnormal sounds.
A chest-x-ray is normal.
What is the next step in care?
A. Prescribe albuterol inhaler for pre-activity use
B. Prescribe a leukotriene inhibitor for daily use
C. Prescribe a brief warm up prior to full activity
D. Order repeat spirometry
E. Order methacholine challenge test
Correct answer:E – Order methacholine challenge test
Key Point: A methacholine challenge test can help diagnose exercise-induced bronchospasm. Other causes may also be investigated with this test. Appropriate treatment can be initiated after diagnosis.
Discussion: Exercise-induced bronchospasm is also called exercise-induced asthma and is a form of reactive airway disease. The symptoms are consistent with asthma and include dyspnea, wheezing, cough, and chest tightness. The symptoms are exacerbated by any activity that requires increased respiratory ventilation and typically increase with the inhalation of cool, dry air.
Spirometry may show the usual findings indicating reactive airway disease and reversibility, but as in asthma, this test may be normal in many patients. A methacholine challenge test can help make the diagnosis in these particular patients. A repeat spirometry in this patient will likely be normal.
Answer choices A, B and C are all appropriate therapeutic choices for the treatment of exercise-induced bronchospasm. The diagnosis should be confirmed prior to beginning these options. The leukotriene inhibitors should be used on a daily basis. The short acting beta agonist should be used 5-20 minutes prior to activity and provides symptom relief for up to 4 hours. A brief warmup period in which 60-80% of maximum heart rate is reached may also provide similar benefit.
PMID: 23634861