Lichen sclerosus et atrophicus is a disorder of the skin that can occur anywhere on the body and in all age groups but mainly affects middle-aged and elderly women in the vulvoperineal area. It consists of ivory or pink papules or macules that eventually coalesce into thin, gray, parchment-like areas. Clinically, the main symptoms are severe and intractable itching and vaginal soreness with dyspareunia. Although it has been described to be associated with an increased risk for epithelial malignancy this, in fact, very rarely occurs. The exact nature of LSA is still unknown. The accumulation of evidence does little to clarify its pathogenesis and etiology. The different reports indicate at least three general possibilities; autoimmune, metabolic, and more recently infectious etiology. The coexistence of such diverse findings in one disease entity may indicate one of the two; either we are facing a group of very similar conditions, which will be separated in the future into several closely related clinical entities, each with its own etiology, or that all findings represent a complex multi-step single pathogenetic mechanism. The latter possibility seems more probable because it has previously been suggested that B. burgdorferi, a recent prime suspect in the pathogenesis of LSA, may induce both metabolic and autoimmune abnormalities in the course of infection. New therapeutic options and attitudes emerge that dramatically improved the conservative treatment of this disease (Table 5).(ABSTRACT TRUNCATED AT 250 WORDS)