Polymorphous light eruption: successful reproduction of skin lesions, including papulovesicular light eruption, with ultraviolet B.

Thirty patients suffering from polymorphous light eruption (PLE), selected by criteria pointing to UVB sensitivity, were phototested for reproduction of skin lesions. Twenty-seven patients (90.0%) had symptoms compatible with or very similar to papulovesicular light eruption (PVLE). Of the 30 patients, 56.7% developed typical lesion of PLE at the test site by provocative phototesting with UVB. Eruptions of the immediate onset type were apt to be reproduced by multiple repeated irradiation, but those of the delayed onset type were reproduced by a single high-dose exposure. In addition, pruritus at the test site seen in all patients was thought to be an important diagnostic symptom. It was obvious that UVB played an etiological role in PLE, including PVLE.