Porokeratosis in chronic leg plaques in a patient with poor health literacy

Porokeratosis is a rare disease of the skin, characterized histopathologically by abnormal keratinization; it commonly affects photo exposed sites. Its exact etiology is unknown, but it may result from the interaction of genetic and environmental factors. However, this is an important disease to keep on the differential diagnosis of papules or plaques in the lower limbs, as it may progress to malignancy, most commonly squamous cell carcinoma.