What Are Capillary Malformations?
A capillary malformation (also known as a port-wine stain or port-wine birthmark), is a flat, sharply defined pink to red discoloration of the skin. A person may have one or multiple capillary malformations. These lesions may cover a large surface area or may be scattered and appear as smaller spots of color. Capillary malformations can be found be anywhere on the body.
Capillary malformations are a group of capillaries (tiny blood vessels of the skin) that form abnormally Capillary malformations have increased diameter (wider blood vessel tube) and number of capillaries, which makes the skin blood vessels more visible. These vessels form incorrectly before a baby is born. Capillary malformations are not caused by any known drug, medication or environmental factor that the baby may have been exposed to during the pregnancy.
A genetic change (mutation) has been found in affected skin of capillary malformations, but not present in nearby normal skin. Most common genetic mutations are GNAQ and GNA11. Most capillary malformations are not inherited. When a person has multiple lesions or has other family members with similar birthmarks, he or she could have an inherited condition.
Another capillary vascular lesion, nevus simplex, is seen in newborn infants. This is often confused with capillary malformations. When these birthmarks appear on the forehead, eyelids, nose, or upper lip, they are called "angel kisses." When located on the back of the neck, scalp, or back, the lesions are called "stork bites." These lesions have a typical pattern on the skin and typically fade by 1-2 years of age. They do not require treatment.
