Disseminated tinea corporis by Trichophyton mentagrophytes

Trichophyton(T.) mentagrophytes is a zoophilic or anthropophylic dermatophyte causing cutaneous human fungal disease. Atypical, disseminated clinical presentations may be seen in immunocompromised patients. It is also hard to diagnose tinea corporis when patients are using corticosteroid or have other dermatologie diseases. Herein, we report on an interesting case of tinea corporis caused by T. mentagrophytes in a patient with Cushing syndrome. A 75-year-old woman presented with pruritic, scaly, erythematous patches, papules and plaques on the face, neck, trunk and extremities for 7 months. She had been diagnosed with psoriasis at the local clinic and taking steroid (prednisolone, 20 mg/day) intermittently for 17 years. Potassium hydroxide smear showed several hyphae on microscope. Fungus culture showed a growth of colonies with whitish granular colonies surface and yellowish brown colored reverse. Characteristic grape-shaped microconidia, spiral hyphae and macroconidia were shown on the lactophenol cotton blue stain identified the colony as T. mentagrophytes. Lesions showed a marked improvement with oral itraconazole 200 mg/day for 14 days and topical lanoconazole cream for 30 days. It is important that when patient has eczematous lesions which are resistant to treatment, we should consider tinea incognito.