Tinea incognito due to Trichophyton mentagrophytes.

Tinea incognito is a dermatophytosis of atypical clinical character, usually misdiagnosed and treated with corticosteroids. We report a case of tinea faciei modified by high potency topical corticosteroids in a 54-year-old woman. Deep, intense inflammatory plaque with boggy, pustular surface located on the right cheek was found. Direct microscopy and culture confirmed dermatophytosis and led to the identification of Trichophyton mentagrophytes var. mentagrophytes. Complete resolution occurred after treatment with oral terbinafine.