A 39-year-old woman is admitted to the hospital for a one month history of worsening dyspnea and cough accompanied by occasional fever. She recently developed hemoptysis which is what brought her to the hospital. During the same time period she has noticed the onset of skin nodules along the outer surfaces of her arms from the wrist to the elbow. Her past medical history is pertinent for atopic dermatitis and allergic rhinitis. She uses an intranasal steroid for rhinitis but takes no other medications.
On physical examination, her temperature is 100.4 °F, blood pressure is 135/78 mm Hg, pulse rate is 88/minute, and respiration rate is 25/minute. Nasal polyps are noted. Diffuse crackles are heard in both lung fields. There are palpable subcutaneous nodules along the extensor surfaces of the arms and legs. The remainder of the physical examination is normal.
Lab findings include:
Leukocyte count
14,500/µL, 22% eosinophils
Creatinine
0.8 mg/dL
IgE
250 U/mL
ANCA
Positive
Antimyeloperoxidase antibodies
Positive
Antiproteinase 3 antibodies
Negative
Urinalysis
Normal
A chest x-ray shows patchy opacities in both lung fields.
Which of the following is the most likely diagnosis?
A. Granulomatosis with polyangiitis
B. Microscopic polyangiitis
C. Rheumatoid arthritis
D. Eosinophilic granulomatosis with polyangiitis
E. Eosinophilic pneumonia
Correct answer:D – Eosinophilic granulomatosis with polyangiitis
Key Point: Eosinophilic granulomatosis with polyangiitis (formerly known as Churg-Strauss disease) is characterized by eosinophilia, migratory pulmonary infiltrates, skin findings such as nodules or purpuric rash, and peripheral neuropathy (usually mononeuritis multiplex) in a patient with a history of atopy (allergic rhinitis, dermatitis, asthma).
Discussion: Eosinophilic granulomatosis with polyangiitis is an ANCA-associated vasculitis that is notable for its associated eosinophilia and occurrence in patients with a history of atopy. It is a multisystem disease when in its most active phase and particularly affects the pulmonary, ENT, skin, and nervous systems. Antimyeloperoxidase antibodies are most common, but ANCA may be absent in up to 40% of patients.
Other ANCA-associated vasculitides to consider in this scenario are granulomatosis with polyangiitis (GPA) and microscopic polyangiitis. These would be unusual diagnoses in the presence of prominent eosinophilia, and, in the case of GPA, in a patient with a lack of sinus involvement.
Rheumatoid arthritis can involve the pulmonary and skin systems but is not associated with significant atopy or eosinophilia. Also this patient has no history of joint symptoms.
Acute eosinophilic pneumonia can appear much like this clinically although skin findings are not a prominent feature. Also, there is no association with ANCA. If ANCA testing were negative in this scenario, the diagnostic workup should probably include testing to investigate acute eosinophilic pneumonia as a possibility.
PMID: 23044708