Low-dose interferon alfa-2b for the treatment of Churg-Strauss syndrome with prominent skin involvement.

A 68-year-old man presented with a medical history of recurrent bronchial asthma and sinusitis maxillaris. He had a severe bronchial infection that was treated with a combinationproductofsulfamethoxazoleandtrimethoprimand subsequentlywithcefadroxil incombinationwith low-dose (20 mg/d of prednisolone) therapy for treatment of the asthma. Three weeks after discontinuation of of antibiotic therapy but continuation of use of prednisolone, 20 mg/d, he developed severe bronchial asthma, sinusitis, systemic hypereosinophilia, and characteristic granulomatous skin lesions on the upper half of the back, in the axilla and inguinal region, rapidlyexpandingwithindays (Figure1A). Skin lesionsconsistedof sharplymarginated,erythematous plaques of dull red with a central clearing and a centrifugalspread(Figure1A).Thepatientreportedoccasionalmild pruritus.ThepresumptivediagnosisofChurg-Strauss syndrome (CSS) was confirmed by histological examination of lesional skin, showing a massive inflammatory infiltrate composedofnumerouseosinophilsandlymphocytesreaching from the midcorium to the lower margin of the biopsy specimen (Figure2A). Pulmonary examination revealed an obstructive and restrictive respiratory disease, as shown by chest x-ray examination, body plethysmography with a forced expiratory volume in 1 second of only 50% (1.18 L), andbronchial lavage, containing81%eosinophils.Leukocyte and eosinophil counts and serum levels of interleukin 5 (IL-5) and eosinophilic cationic protein (ECP) were elevated (Figure 3A-B).