Allergic bronchopulmonary mycosis in Schizophyllum commune with positive Aspergillus-specific IgE antibodies: A case report.

Schizophyllum commune is the third most common causative fungus of allergic bronchopulmonary mycosis(ABPM). Two-thirds of ABPM caused by S. commune can be positive for Aspergillus fumigatus-specific IgE, which can be difficult to diagnose. Our patient presented to our hospital with wet cough for 3 months and chest pain for 3 days. Blood tests showed IgE 1522 IU/mL, eosinophils 688/mm³, A. fumigatus -specific IgE 2.24 UA/mL, and chest computed tomography showed high-attenuation mucus. Bronchoscopy showed mucus plugs and speculum examination showed filamentous fungi, but various culture tests did not detect A. fumigatus, Asp f 1-specific IgE was negative, and S. commune was detected in the culture of bronchial washing. Since he was positive for S. commune-specific IgE and IgG, he diagnosed ABPM caused by S. commune. These findings demonstrate the importance of identifying the causative fungus in ABPM by detailed examination.