General Medical Information

Hypopigmented and Hyperpigmented Lesions

Wilberto Nieves-Neira
Bhagirath Majmudar
Ira R. Horowitz

Vitiligo is a patchy but complete loss of skin pigmentation due to the absence of melanocytes. Microscopically there is no specific alteration, and on examination the texture of the skin is normal. Pinkish-white to ivory patches are sharply demarcated and may spread and coalesce. The patches of depigmented skin may occur anywhere in the body and are asymptomatic. Vulvar involvement should be assessed carefully. Trauma or irritation may lead to loss of pigmentation in the vulva. Likewise, it should not be confused with lichen sclerosus. There is no specific treatment. Reassurance to the patient and mother should make them aware that no serious problems are associated with vitiligo.

Melanocytic nevi (common moles) occur anywhere on the body, including the vulva. Nevi are caused by nests of melanocytes within the dermis and epidermis. They present as 2- to 5-mm, flat, well-circumscribed, brown or black macules. Compound melanocytic nevi are raised, dome-shaped, brown or skin-colored papules. Lentigenes are flat areas of hyperpigmentation caused by increased numbers of melanocytes in the basalis. Lesions are 1- to 2-mm, brown or brown-black macules on the skin and mucous membranes.

An epidermal nevus is a congenital cutaneous anomaly that can occur at any skin site, including the anogenital region. The lesion is characterized by a linear and whorled pattern with a midline demarcation (Blashcko’s lines). Epidermal nevi usually are present at birth, but they may not become apparent until childhood. The initial appearance is a smooth, hyperpigmented patch or a rough, skin-colored plaque. With time, epidermal nevi become verrucous and thus may be confused with condylomata. An inflammatory variant may be pruritic and present with unilateral, linear vulvar erosions.