A rare case of allergic bronchopulmonary mycosis caused by Alternaria alternata.

A rare case of allergic bronchopulmonary mycosis (ABPM), caused by Alternaria alternata, is reported in an immunocompetent resident of Delhi. Her complaints included a generalized, urticarial skin rash and occasional pain in the right lower chest. Her differential count showed eosinophils, 22%; absolute eosinophil count (AEC), 2400 cells/μl; and total IgE, 4007 IU/ml. The computerised tomogram (CT) scan of her thorax showed an enhancing lesion with surrounding ground glass haziness in the right lower lobe. Histopathologic examination of the resected lung revealed a necrotizing granulomatous inflammation, parenchymal infiltration by eosinophils, lymphocytes, neutrophils, plasma cells and some exudative bronchiolitis suggestive of ABPM. Observation of KOH wet mounts of repeat sputum and BAL samples demonstrated the presence of septate, brownish hyphae and cultures of these specimens yielded A. alternata (identified by sequencing of the ITS region). Her serum showed a three-fold higher specific IgE to A. alternata antigens than control levels, and the type I cutaneous hypersensitivity response to antigens of A. alternata was strongly positive. She was treated successfully with oral glucocorticoids and itraconazole. To our knowledge, ABPM due to Alternaria alternata has not been reported previously.