Lichen nitidus. A study of forty-three cases.

Among forty-three cases of lichen nitidus studied, twenty-one patients were Caucasian, twenty-one were Negro, and one was Spanish-American, ranging in age from five to fifty-eight years. The arm, forearm, trunk, and genitalia were sites most commonly involved. Clinically, the eruption usually appeared as tiny papules. Histologically, the papules showed a parakeratotoic "cap," epidermal atrophy, liquefaction degeneration of the basal layer, and a dermal infiltrate of lymphocytes, epithelioid cells, and sometimes giant cells.