An Overview of Klippel-Trenaunay Syndrome

Klippel-Trenaunay syndrome (KT) is a blood vessel disorder that is present at birth. Researchers aren't sure why it happens because it doesn't seem to be passed down genetically. Klippel-Trenaunay syndrome affects both males and females. It is not known exactly how often it occurs.

Blood vessel with blood cells, illustration


The symptoms of KT syndrome may include:

  • A large port-wine stain birthmark (usually the first symptom noticed) caused by tiny blood vessels under the skin. It may be dark red, purple, be raised up, or may have bumps on it that bleed easily. Most often the port wine stain is large and since KT syndrome usually affects a leg (three times more likely than other parts), the birthmark may cover from buttock and hip to toe on the affected side of the body, as an example.
  • Hemangiomas (abnormal masses of blood vessels)
  • Varicose veins
  • Excessive growth of soft tissue and bone in the affected leg

The blood vessel problems and the overgrowth lead to bleeding, pain, skin infections (cellulitis), difficulty walking, and blood clots (which may cut off blood circulation in the leg, or travel to other parts of the body and cause damage). Each person with Klippel-Trenaunay-Weber syndrome is affected differently, and the problems experienced may range from only mildly uncomfortable to severely disabling.

Other blood vessel disorders with similar symptoms are Parkes-Weber syndrome and Sturge-Weber syndrome. Both cause port wine stain and blood vessel malformations. However, unlike Klippel-Trenaunay syndrome, Parkes-Weber syndrome and Sturge-Weber syndrome include tangles of blood vessels called arteriovenous malformations (AVMs), and are more likely to be severe with more difficult symptoms.


The symptoms of Klippel-Trenaunay syndrome are present at birth. Diagnosis is based on the symptoms, especially the presence of the port wine stain and excessive growth of soft tissue or bone. A CT scan and MRI are helpful in determining the extent of the syndrome.


Treatment of KT syndrome focuses on the symptoms. Many people are helped by simple treatments such as elastic compression stockings, which reduce pain and swelling. Laser therapy can reduce or eliminate the port wine stain.

Sometimes surgery is needed to remove a large hemangioma or to remove excess tissue from a leg that is badly overgrown. In rare instances, the affected leg may need to be amputated because of blood clots or severe overgrowth.

Although debilitating and painful, many people who have Klippel-Trenaunay syndrome do well with little treatment. Surgery is only needed in severe cases.

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  • "Description of Klippel-Trenaunay Syndrome." Understanding Klippel-Trenaunay Syndrome. Klippel-Trenaunay Syndrome Support Group. 26 May 2009