Erythropoietic Protoporphyria (EPP)

Cutaneous photosensitivity followed by acute, then chronic, skin lesions on sun-exposed areas characterizes this disorder. Shown here on the dorsum of a 46-year-old man's hand is the papular thickening that gives the cobblestone appearance typical of chronic untreated EPP. Diagnosis was not made until 8 years after the onset of lesions, and follow-up was poor because of patient noncompliance. This patient also had generalized jaundice.

EPP is marked by protoporphyrins in red blood cells, plasma, and feces. Beginning early in life, patients experience a burning, stinging sensation on exposure of skin to sunlight. Lesions are initially erythematous and edematous; purpura is not uncommon. After repeated episodes of sun exposure, small, atrophic, waxy scars may develop on the ears and nose, around the eyes, and on the dorsum of the hands. Changes of papular thickening with hyperpigmentation or hypopigmentation occur later.