Hydroa vacciniforme.

Two patients with hydroa vacciniforme, a rare photodermatosis of unknown etiology, demonstrated distinctive scarring and vesiculobullous skin lesions on light-exposed body areas. Results of blood and urine porphyrin studies were normal, and no systemic abnormalities were noted. A small bullous lesion was produced in normal skin in case 1 with 15 times the minimal erythema dose of ultraviolet energy. The conditions of both patients improved while they were taking beta carotene orally.