Delayed contact allergies in patients with photosensitivity dermatitis.

Delayed contact allergies and the clinical course of the skin disease were investigated in 14 patients with photosensitivity dermatitis/actinic reticuloid and 145 patients with polymorphous light eruption type eczema. Hypersensitivity to chromium and rubber chemicals was encountered in photosensitivity dermatitis more often than in polymorphous light eruption eczema and in the comparison series of 1714 patients with other types of dermatitis. In the eczema group, delayed contact allergies to chromium, rubber chemicals, neomycin, clioquinol, balsam of Peru, fragrance and colophonium were more frequent than in the comparison group, suggesting that at least delayed contact allergy to chromium and rubber chemicals may be of significance in the development of photosensitivity in many patients who suffer eczematous reaction to sunlight.