Definition: An inflammatory, pruritic disease of the skin and mucous membranes, which can be either generalized or localized. It is characterized by distinctive purplish, flat-topped papules having a predilection for the trunk and flexor surfaces. The lesions may be discrete or coalesce to form plaques. Histologically, there is a "saw-tooth" pattern of epidermal hyperplasia and vacuolar alteration of the basal layer of the epidermis along with an intense upper dermal inflammatory infiltrate composed predominantly of T-cells. Etiology is unknown.
a skin dis; sometimes called simply "lichen": check text & its bibliog; lichen planus atrophicus: index here & do not confuse with LICHEN SCLEROSUS ET ATROPHICUS
ExamplesLichen Planus, Oral
Other names Lichen Ruber Planus; Lichen Rubra Planus