Dermatophytic granuloma caused by Microsporum canis in a heart-lung recipient.

We present a case of dermatophytic granuloma caused by Microsporum canis in a heart-lung recipient. This 66-year-old man was seen for erythematous pustules and papules on the forearm. The diagnosis was suspected after histological examination showing an inflammatory infiltrate in the upper dermis with giant cells containing intracytoplasmic fungal elements. Cultures of the skin biopsy confirmed the diagnosis identifying M. canis. Our case emphasizes the possibility of deep dermatophytic infections in immunocompromised patients. There are only 4 additional reports of M. canis infection responsible for invasion of the dermis in such patients. The follicle involvement probably explains these dermal lesions due to the progression of the dermatophyte from the hair follicle to the dermis. In our observation topical antifungal therapy alone was unsuccessful and fluconazole seems to be the treatment of choice for these M. canis invasive dermal cutaneous infections.