Klippel-Trenaunay Syndrome (KTS) | Symptoms and Causes

What are the symptoms of Klippel-Trenaunay syndrome?

KTS often has three characteristic signs:

  • capillary malformation covering one or more limbs (arm or leg)
  • hypertrophy — or excessive growth — of a limb (usually a leg)
  • abnormal blood vessels, including veins, capillaries and lymphatic vessels
  • (vessels that drain fluid that leaks from arteries and veins and return that fluid to the bloodstream)

KTS affects different kids in different ways. One child may have a mild form of the syndrome with a small capillary malformation and one hand or foot slightly larger than the other. Another child may have a capillary malformation that runs from their chest down their leg, lots of swelling and one limb that is much larger than the other. Symptoms of KTS include:

  • blood clots
  • cellulitis (infections in the skin) — your child may be more prone to infection because they are more likely to bleed easily as a result of the abnormal capillaries near the surface of their skin
  • anemia due to blood loss from easy bleeding
  • pain and heaviness of the affected limb, often severe
  • difference in size between the affected and non-affected limb
  • lymphatic abnormalities such as cysts and swelling
  • swollen veins

What causes Klippel-Trenaunay syndrome?

No one knows the precise cause of KTS. Some doctors think it's caused by a mutation that occurs before birth (but isn’t inherited) in the cells that form the lymphatic system, veins and other tissues. No known food, medication or activity during pregnancy can cause KTS.