Trichophyton violaceum infection in three black brothers

Abstract

Case 1 was a 3-year-old with tinea capitis, while Case 2 was a 5-year-old with kerion celsi. These conditions developed between December 1997 and January 1998 when the patients were living in Canada. Case 3 was a 7-year-old who developed kerion celsi in March 1998 in Japan. For Cases 1 and 2, the referring doctor had detected a fungal infection a few weeks previously, and griseofulvin was administered orally to Case 1 for three weeks and Case 2 for one week prior to consultation at our department. Both Cases 1 and 2 visited our department initially on May 7, 1998 with the causative agent separated from their lesions by the referring doctor respectively. The causative agent was identified as Trycophyton violaceum by our department. KOH-prepared direct microscopy and culture were positive for Case 1, but negative for Case 2. Infected hairs of Case 1 showed a chain of large arthrospores arranged in parallel rows inside the hair. Case 3 visited our department initially on May 21, and T. violaceum was also isolated from this patient's lesion. A reddish purple isolate that was stored for five months after isolation and culture was subcultured using a Sabouraud agar containing thiamin. After two months, brown colonies without red pigment were seen in the reddish purple colonies. Slide culture performed for both colonies showed intercalary and terminal chlamydospores, thus confirming that they were the same fungus. These findings appear to represent the conversion of T. violaceum into T. glabrum.