ABSTRACT
Intertriginous granular parakeratosis is a condition presenting with erythematous hyperkeratotic papules and plaques localized to the intertriginous areas such as axilla, groin and perianal area. Although the etiology of granular parakeratosis remains obscure, it is probably caused by a defect in conversion of profilaggrin to filaggrin. The defect results in a failure to degrade keratohyaline granules and to aggregate keratin filaments during cornification. We report a 59-year-old man who presented with erythematous fissured patches on the perianal area for 1 year. Histopathologic examination revealed mild acanthosis and severe parakeratosis with prominent keratohyaline granules in the epidermis and vascular proliferation and RBC extravasation in the dermis.