Definition of Klippel-Trenaunay syndrome:

Klippel-Trenaunay syndrome is a group of findings consisting of:

• Multiple port wine stains or other blood vessel malformations, including dark spots of skin.
• Excessive growth of bones and soft tissue. This occurs most commonly in the legs, but may affect the arms, the face, head, or internal organs.
• Varicose veins that may be noted in early infancy. However, they are more likely to be seen later in childhood or adolescence. Bleeding from the rectum and blood in the urine may also occur.

Causes, incidence, and risk factors:

Most cases of Klippel-Trenaunay syndrome occur for no apparent reason, although a few cases are thought to be passed down through families (inherited), possibly as an autosomal dominant trait.