Verrucous porokeratosis of Mibelli on the buttocks mimicking psoriasis.

The typical presentation of porokeratosis of Mibelli is of a solitary plaque with a prominent raised border cleaved by a central furrow. The central portion of the plaque is usually slightly atrophic. The plaques vary in size from a few millimeters to several centimeters in diameter and tend to be acrally distributed, though they can occur on any part of the body. We report an unusual case of verrucous porokeratosis of Mibelli, localized to the natal cleft, that mimicked psoriasis. This entity, though unusual, is not unique. Two similar cases of verrucous porokeratosis of Mibelli limited to the natal cleft region and resembling psoriasis have been reported in the British literature. Verrucous porokeratosis of Mibelli localized to the natal cleft appears to be a distinct clinical entity that can mimic psoriasis. Better recognition of this form of porokeratosis of Mibelli may result in earlier diagnosis and initiation of appropriate therapy.