Photosensitive psoriasis provoked by a suberythematous dose of ultraviolet-B light.
An unusual case of 'photosensitive psoriasis' is reported. This patient had experienced an exacerbation after sea-bathing, and psoriatic eruptions were observed on the sun-exposed areas of the body. Phototesting with ultraviolet-B (UV-B) revealed his minimal erythema dose to be within normal limits. Three to four weeks after phototesting, however, he developed a psoriatic macule on the area exposed to the suberythematous dose of UV-B. The histologic features of the skin lesion provoked by UV-B irradiation were similar to those of naturally occurring lesions on areas covered by clothes. Moreover, failure to reproduce skin lesions following tape-stripping ruled out a proneness of this patient to develop the Köbner phenomenon nonspecifically.
Kudoh
K
K
Department of Dermatology, Tohoku University School of Medicine, Sendai, Japan.
Obata
M
M
Torinuki
W
W
Tagami
H
H
D000328:Adult; D006801:Humans; D008297:Male; D010787:Photosensitivity Disorders / Q000209:etiology* / Q000473:pathology; D011565:Psoriasis / Q000209:etiology* / Q000473:pathology; D011829:Radiation Dosage; D013472:Sunlight / Q000009:adverse effects; D014466:Ultraviolet Rays / Q000009:adverse effects*