noun, plural: port-wine stains
Birthmarks are marks on the skin at birth or shortly afterwards. One of the two major types of birthmarks is the vascular birthmark (the other, pigmented birthmark). Vascular birthmarks are those that arise when blood vessels do not form correctly whereas pigmented birthmarks are those that are associated with a localized overgrowth of melanocytes. They include naevus simplex (salmon patches), hemangiomas, and port-wine stains.
Port-wine stains are a birthmark appearing usually on the head and neck, although they are also seen to form elsewhere, such as on the upper trunk. Those that form on the upper eyelid or forehead may be an indication of pathologic conditions such as Sturge-Weber syndrome (a rare congenital neurological and skin disorder) and Klippel–Trénaunay syndrome (a rare congenital medical condition characterized mainly by port-wine stain, venous and lymphatic malformations, and soft-tissue hypertrophy of the affected limb).
Port-wine stains arise due to an overgrowth of cutaneous capillaries, thus, producing a purplish or reddish skin discoloration. The color accounts for the name. They have color resemblance to Port wine, which is a Portuguese fortified wine produced in Portugal. They are also irregular in appearance and may become thick, forming ridges or bumps. Unlike naevus simplex that usually fades as the child grows, port-wine stains persist throughout life.
Port-wine stains are congenital although in certain rare cases form in early adulthood.
- n(a)evus flammeus