UV-A-PROVOKED LOCALIZED BULLOUS PEMPHIGOID

A 71-year-old woman had noticed the development of blisters on her for ehead 4 months before she was referred to our department. Treatment wi th oral corticosteroids resulted in complete healing, but new blisters subsequently developed on the face, neck and backs of the hands. Afte r the possibility of phototoxic and photoallergic reactions, as well a s an abnormal porphyrin profile, had been excluded, the diagnosis of b ullous pemphigoid was made by histological and direct immunofluorescen t examination. UV-A provocation on the upper arm produced lesions hist ologically and immunohistochemically typical of bullous pemphigoid. Of particular importance was the fact that the blisters were limited str ictly to light-exposed skin areas.