Abstract
A 72-years old man visited our department with the chief complaint of a subcutaneous tumor in the left first interdigital area that was growing relatively rapidly. The fluctuating subcutaneous tumor measured 3cm, and an induration 2cm in size was palpated in the lower layer. When the subcutaneous tumor was incised, bloody pus was discharged. Histopathologically, the induration in the lower layer was a granuloma. In the granuloma, structures assumed to be the fungal hyphae that stained black with Grocott staining were presented. Trichophyton rubrum was isolated from the samples of both the pus and granuloma, and we confirmed the diagnosis of trichophytic granuloma. He has diabetes, but has no previous treatment with systemic immunosuppressive agents or topical use of steroids. Tinea unguium was noted in the feet, but no tinea superficialis was evident in the hands.
