Lichen Planus, Nitidus, and Striatus

Abstract

Lichen planus is an inflammatory disease of the skin, scalp, nails, and mucous membranes. Lesions are classically polygonal, violaceous, flat-topped papules often accompanied by intense pruritus. Postinflammatory hyperpigmentation commonly occurs. Several clinical variants of lichen planus have been reported, some of which have predilection for people of skin of color. Actinic lichen planus primary affects the Middle Eastern population in a sun-exposed distribution. Linear lichen planus has been reported to be more common in Japan. Lichen nitidus is another inflammatory disease of the skin and is often localized to a few areas, such as the penis, abdomen, chest, and arms. Lesions are discrete, flat-topped, uniform papules. A variant of lichen nitidus, called lichen nitidus actinicus, affects dark-skinned patients from the Middle East and Indian subcontinent. Lesions in this variant are found on sun-exposed areas, such as the hands, forearms, and neck. Lichen striatus is an asymptomatic eruption of small, erythematous papules usually seen in small children in which postinflammatory hypopigmentation is common.