ABSTRACT
This chapter discusses a selection of common and important photoexacerbated diseases. Treatment is restriction of light exposure, use of high protection sunscreens, and appropriate treatment of the underlying disorder. Photoaggravated dermatoses represent a very heterogeneous group of conditions that share only one common feature: they can be induced or exacerbated by exposure to sunlight or to artificial therapeutic or cosmetic ultraviolet (UV) radiation. Bacteriological, immunohistopathological, and photo-experimental investigations failed to reveal a cause for this sunlight induced dermatosis. R. Grover’s disease is a nonimmune acantholytic dermatosis. The etiology and pathogenesis of Grover’s disease is unknown. Factors that can trigger the disease include sweat, fever, heat, and sunlight. Patients with psoriasis usually benefit from sunlight and UV phototherapy. However, some patients experience exacerbation of their disease after sun bathing, particularly, after sunburn. Sunlight is a major precipitating cause, with lesions occurring in the spring and summer, with residual hyperpigmentation in the winter.
