Phototesting in lupus erythematosus: A 15-year experience

It has long been observed that sun exposure can induce or exacerbate skin l esions in patients with certain forms of lupus erythematosus. Despite the f requency of photosensitivity in these patients, the mechanism by which ultr aviolet radiation alters the pathogenic course of this disease remains poor ly understood. After development of standardized test methods, our group de monstrated in 1986 that skin lesions in patients with lupus erythematosus c an be experimentally reproduced by UVA and UVB irradiation. In the followin g years, phototesting has received much attention as a valid model to study photosensitivity of different forms of lupus erythematosus and the pathoge netic mechanism of this disease. Further investigations have also made it p ossible to find genetic and immunologic factors associated with photosensit ivity and have helped to identify the pathophysiologic steps involved in th e induction of such skin lesions. We present prototesting results and clini cal correlations of more than 400 patients with different forms of lupus er ythematosus and discuss the recent advances in provocative phototesting.