Birthmarks - pigmented

Alternative names:

cafe-au-lait spots; congenital nevus; hairy nevus; mole; nevi; nevus sebaceous

Definition:

A congenital pigmented skin marking that ranges in color from brown or black to bluish or blue-gray. (See also birthmarks, red.)

Causes, incidence, and risk factors:

Cafe-au-lait spots are a light tan spot, the color of coffee with milk. They may be a normal type of birthmark. The presence of several cafe-au-lait spots larger than a quarter may occur in neurofibromatosis (a genetic disorder that causes abnormal cell growth of nerve tissues).

Nevi (moles) are small clusters of pigmented skin cells. Nearly everyone has moles, which usually appear after birth.

Congenital nevi (moles present at birth) have an increased risk of becoming skin cancer (malignant melanoma). This is especially true if the nevus covers a large area of the body (larger than a fist). All congenital nevi should be examined by a health care provider and any change in the birth mark should be reported. Watch for changes in the size or color, or the appearance of sudden ulceration, bleeding, or itching in the birthmark.

A mongolian spot (also called a mongolian blue spot) is usually bluish or bruised-looking. It usually appears over the lower back or buttocks, sometimes in other areas including the trunk or arms. These are more commonly seen in darker-skinned populations and may persist for months or years but do not become cancer or develop other symptoms.