First Japanese case of disseminated blastomycosis imported from North America: A case report.

Blastomycosis is a fungal infectious disease that can occur in both immunocompromised and immunocompetent populations endemic in North America, with no previous reports in Japan. A 26-year-old Japanese female patient with no relevant medical history presented intermittent left back pain and an abnormal shadow in the left upper lung field eight months ago at a local clinic. She was referred to our hospital for further evaluation and treatment. The patient currently lives in Japan, but until two years ago had spent several years in New York, Vermont and California. Chest computed tomography revealed a 30 mm mass with a cavity in the left pulmonary apex. The specimens obtained by transbronchial biopsy showed periodic acid-Schiff stain (PAS)-positive and Grocott-positive yeast-like fungi scattered among the granulomas, with no malignant findings, and the initial pathology did not lead to a definitive diagnosis. She was empirically started on fluconazole because of onset of multiple subcutaneous abscesses and was referred to the Medical Mycology Research Center. Although antibody tests could not diagnose the disease, blastomycosis was suspected based on the pathology of the skin and lung tissue at the Medical Mycology Research Center, and Blastomyces dermatitidis was identified by ITS analysis of the rRNA region. Her symptoms and CT findings gradually improved with fluconazole. We reported the first Japanese case of blastomycosis with pulmonary and cutaneous involvement in Japan. As the number of overseas travelers is expected to continue increasing, we would like to emphasize the importance of travel history interviews and information of blastomycosis.