Marguery M C
Service de dermatologie Hôpital Purpan, Toulouse.
Rev Prat. 2000 Jun 15;50(12):1315-9.
Photodermatosis are dermatoses where there is an abnormally exaggerated sensitivity to sunlight, termed photosensitivity, that is often drug-induced. Such drug-induced photosensitivity is due to the mechanism of photosensitivization that induces two types of reaction, phototoxic and photoallergic. The phototoxic reaction is photochemical, irritative and common, and can occur in any individual without any particular predisposition. The photoallergic reaction is a photoimmunologic, cell-mediated hypersensitivity reaction. It is much more rare and occurs only in some individuals with predisposition. Clinically, the phototoxic reaction usually manifests by a cutaneous "sunburn" type eruption, and the photoallergic reaction by eczema. Photosensitizing drugs are numerous: antibiotics, nonsteroid anti-inflammatory drugs, diuretics, antimitotic drugs, psychiatric drugs, amiodarone, calcium channel blockers, fibric acid derivatives, etc. Diagnosis is based on recognition of an eruption localized in zones exposed to sunlight occurring in the context of photosensitizing drug intake, correlated with the results of photobiological laboratory investigations.
光皮肤病是对阳光有异常过度敏感性（称为光敏感）的皮肤病，这种光敏感通常由药物引起。这种药物性光敏感是由于光致敏机制导致的，会引发两种反应，即光毒性反应和光变应性反应。光毒性反应是光化学性、刺激性且常见的，可发生于任何个体，无任何特殊易感性。光变应性反应是一种光免疫性、细胞介导的超敏反应。它更为罕见，仅发生于某些具有易感性的个体。临床上，光毒性反应通常表现为皮肤“晒伤”样皮疹，光变应性反应则表现为湿疹。引起光敏感的药物众多：抗生素、非甾体抗炎药、利尿剂、抗有丝分裂药物、精神科药物、胺碘酮、钙通道阻滞剂、纤维酸衍生物等。诊断基于认识到在服用光致敏药物的情况下，出现在暴露于阳光区域的皮疹，并与光生物学实验室检查结果相关联。
