Human dermatophytosis caused by Trichophyton equinum.

A case of dermatophytosis caused by Trichophyton equinum is reported. A 25-year-old man employed at a breeding center of a horse racing course was infected on the left arm in August, 1981. The lesion had a vesicle or a small pustule accompanied by severe itching. The fungal elements of the scale were identified by microscopic observation. Griseofulvin administration was found to be very effective for treating this infection. In a mycological examination, T. equinum was isolated mainly on cycloheximide-chloramphenicol Sabouraud's dextrose agar and chloramphenicol potato dextrose agar. Equine dermatophytosis was quite prevalent at this race course, so that this area as well as equipment used for the maintenance and care of the horse was very likely to be the source of the patient's infection.