Authors: Dr Achala Liyanage, Dermatology Fellow, Waikato Hospital, Hamilton, New Zealand; Assoc Prof Patrick Emanuel, Dermatopathologist, Auckland, New Zealand. January 2015.
Tinea incognita (often spelled incognito) is an atypical presentation of tineainfection when topical steroid applications are used incorrectly for the treatment of dermatophytosis. The disease extends despite improvement of itch.
Histology of tinea incognita
In tinea incognita, the epidermis is often mildly spongiotic, and the dermalinflammatoryinfiltrate is less heavy than usual dermatophytosis. Multiple branched, septate hyphae and small spores are present in the stratum corneum. These can often be seen on H-E stain (figures 1, 2, 3) but special stains are often needed to reveal the fungi and demonstrate their morphology.