The photoaggravated dermatoses.

The photoaggravated dermatoses are diverse diseases adversely affected by sunlight or artificial ultraviolet (UV) exposure. The role of UVR is often well-recognized, as in lupus erythematosus (LE) and bullous pemphigoid (BP). Immunologic theories for the cause of the photosensitivity in lupus erythematosus are the production of UV-DNA antibodies with subsequent immune complex formation, a partial defect in DNA repair following UV exposure, and the release or stimulation of potent cutaneous immunologic mediators. However, mechanisms are still not fully elucidated. Photosensitivity has also been described in erythema multiforme, actinic lichen planus, viral exanthems, cutaneous T-cell lymphoma, eczema, and psoriasis. Treatment is restriction of light exposure, use of high protection sunscreens, and treatment of the underlying disorder.