[The pathogenesis of lichen ruber planus--a modern concept]

Although lichen planus (LP) is still considered a disease of unknown origin, we succeeded in developing a synoptic pathogenetic concept based on the various scientific studies in this field, which may supply a rational foundation for the empirically established therapy. Genetic and metabolic factors predispose to the development of LP, which can be viewed as a type-IV reaction against immunologically altered keratinocytes. The papule is the result of exaggerated repair mechanisms.