Lichen sclerosus is a chronic dermatosis of uncertain etiology affecting the skin and mucosa of individuals of all races. Lichen sclerosus most commonly presents in 2 peaks of incidence: postmenopausal women and prepubertal girls. Childhood and adolescent cases in boys have increasingly been recognized. Lesions occur mostly on the genitalia, perineum, or perianal skin, but extragenital lesions are also observed. Lichen sclerosus lesions are atrophic patches or ivory-white plaques preceded by papules. Because of petechiae, erosions, and purpura, the disease can easily be mistaken for sexual abuse in young girls. Lesions can itch, burn, and cause dysuria, constipation, and painful defecation. Advanced disease may obliterate genital anatomy. Extragenital lesions are rarely symptomatic.

There is a well-documented association of lichen sclerosus and autoimmune diseases such as alopecia areata, autoimmune thyroiditis, and vitiligo. Some cases are thought to due to infectious etiology including Borrelia spp. and hepatitis C virus.

Lichen sclerosus does not usually resolve with puberty, but it may improve.

An increased risk of genital squamous cell carcinoma (SCC) has been observed in adult male and female patients with chronic untreated genital lichen sclerosus. For girls and women with vulvar lichen sclerosus, the lifetime risk of vulvar SCC is about 5%.