A case of chromomycosis caused by Fonsecaea pedrosoi and a review of reported cases of dematiaceous fungal infection in Japan

We report a case of chromomycosis caused by Fonsecaea pedrosoi that developed in the left buttock of a 63-year-old female farmer. About 4 years ago, the patient developed erythema in the left buttock, which gradually spread. At the first consultation, we noted a well-defined, red-brown, infiltrated erythematous plaque (8 x 6 cm). Histopathological examination revealed a granulomatous lesion, containing sclerotic cells, associated with giant cells in the upper dermis. The causative fungus was difficult to identify due to low conidiogenesis, but was eventually identified by slide culture as F. pedrosoi. Excision and skin graft were performed, and no recurrence has been observed after 2 years. In Japan, 212 cases of dematiaceous fungal infection were reported in the period from 1982 to 2001. The causative fungus was F. pedrosoi in the majority of cases (126/212; 66%), followed by Exophiala jeanselmei (36/212; 19%). Similar incidence of dematiaceous fungal infection was reported in male and female patients. The upper limbs were affected most frequently in both male and female patients. Ten cases were associated with visceral lesions.