Photosensitivity in patients with lupus erythematosus: a clinical and photobiological study of 100 patients using a prolonged phototest protocol.

Background: There is a clear relationship between ultraviolet (UV) radiation (UVR) and the clinical manifestations of patients with lupus erythematosus (LE). Cutaneous lesions are induced or exacerbated by exposure to UVR. Of patients with LE, 24-83% are reported to be photosensitive to UVR.