Cutaneous dermatophyte invasion below the stratum corneum in an immunocompetent patient: To blame mixed creams or not?

Abstract

Dermatophytes are pathogenic fungi that infect human skin, nails, and hair. Dermatophytes very rarely invade the epidermis below the stratum corneum in an immunocompetent host. Herein, we report a case of invasive cutaneous dermatophytosis in a 30-year-old immunocompetent male who had a history of intermittent mixed cream application on the lesion. Biopsy from the plaque showed neutrophilic spongiosis with superficial perivascular infiltrate of neutrophils, eosinophils, and lymphocytes. On periodic acid–Schiff staining, multiple branched septate hyphae in the stratum corneum were seen. Some of them were seen invading the stratum granulosum and upper spinous layer. On culture, Trichophyton schoenleinii species was isolated.