Phaeohyphomycotic cyst caused by Colletotrichum crassipes

A case of phaeohyphomycosis is reported in a male renal transplant recipien t with a nodular lesion in the right leg who was treated with immunosuppres sing drugs. The lesion consisted of a purulent cyst with thick walls. The c yst was excised surgically, and the patient did not receive any antifungal therapy. One year later he remains well. Histological study of the lesion s howed a granulomatous reaction of epithelioid and multinucleate giant cells , with a central area of necrosis and pus. Fontana-Masson staining demonstr ated the presence of pigmented hyphal elements. The fungus Colletotrichum c rassipes was grown in different cultures from the cyst. The in vitro inhibi tory activities of eight antifungal drugs against the isolate were tested. Clotrimazole and UR-9825 were the most active drugs. This case represents t he first known reported infection caused by this rare species.