Port-wine stain

Nevus flammeus
Mikhail Gorbachev has a prominent port-wine stain on his forehead.
Classification and external resources
Specialty	medical genetics
ICD-10	Q82.5 (ILDS Q82.510)
ICD-9-CM	757.32
OMIM	163000
DiseasesDB	10384
MedlinePlus	001475
eMedicine	derm/295
MeSH	D019339
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A port-wine stain (nevus flammeus), also commonly called a firemark, is almost always a birthmark; in rare cases it can develop in early childhood. It is caused by a vascular anomaly (a capillary malformation in the skin). Port-wine stains are named for their coloration, which is similar in color to Port-wine, a fortified red wine from Portugal.

Port-wine stains ordinarily persist throughout life. The area of skin affected grows in proportion to general growth. Port-wine stains occur most often on the face but can appear anywhere on the body, particularly on the neck and upper trunk. Early stains are usually flat and pink in appearance. As the child matures, the color may deepen to a dark red or purplish color. In adulthood, thickening of the lesion or the development of small lumps may occur.

Port-wine stains may be part of a syndrome such as Sturge–Weber syndrome or Klippel–Trénaunay–Weber syndrome.

Nevus flammeus may be divided as follows:

Port-wine stains were shown to be caused by a somatic activating c.548G→A mutation in the GNAQ gene. An association with RASA1 has also been described.

A healthcare provider can usually diagnose a port-wine stain based entirely upon the history and appearance. In unusual cases, a skin biopsy may be needed to confirm the diagnosis. Depending on the location of the birthmark and other associated symptoms, a physician may choose to order a measurement of intraocular pressure or X-ray of the skull.

A MRI scan of the brain may be performed (under anesthesia) on infants who have a port-wine stain in the head area in order to check for signs of Sturge-Weber syndrome.

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Wikipedia