Common Childhood Conditions

Klippel-Trénaunay Syndrome

What does Klippel-Trénaunay Syndrome (KTS) look like?

Klippel-Trénaunay Syndrome

Klippel-Trénaunay Syndrome in the lower extremity.

KTS often has three characteristic signs:

  • Port wine stain covering one or more limbs (arm or leg)
  • Vascular anomalies, usually vein swelling or malformation
  • Hypertrophy or atrophy of a limb (one affected arm or leg is either larger or smaller than the unaffected limb)

Hypertrophy occurs most commonly in the lower limbs (legs), but may affect the arms, face, head or internal organs. A wide range of other bone and skin abnormalities sometimes also exists.

KTS involves the lower limbs in about 90 percent of the patients.

In rare instances, there is no port wine stain, and not all three abnormalities need always be present for the syndrome to exist.

In one type of KTS, which is known as the Parkes-Weber variant, patients have arteriovenous fistulae (multiple arteriovenous connections), which can result in heart failure if untreated.

How is Parkes-Weber Syndrome related to KTS?

In Parkes-Weber Syndrome, one or more high-flow arteriovenous malformations lead to overgrowth of limbs that is similar to, but usually more severe, than that found with KTS.

KTS does not include AV malformations. An angiogram will be normal in KTS and abnormal in Parkes-Weber Syndrome.

In Parkes-Weber Syndrome, the limb is usually pinker and warmer due to the fistulas (AV malformations). These fistulas are abnormal connections between the arteries and veins and are the type of lesions that can lead to cardiac problems.

Parkes-Weber Syndrome is rarer than KTS and more likely to affect an upper limb (but may still affect the lower limb).

What Causes KTS?

KTS is a rare congenital (present at birth) disorder. The cause is unknown. It is the most common condition involving combined vascular malformations (those including capillary, venous, lymphatic or arteriovenous malformations).

Will KTS Change?

Bony enlargement (usually in the arms or legs) is usually not present at birth, but may appear within the first few months or years of life and may become more problematic during puberty. The affected area grows longer and thicker due to increased blood supply.

Sometime after puberty and before age 30, the port wine stain develops small blood-filled, bubble-like lesions in the skin involved by the PWS that can bleed on their own.

I Believe My Child Has KTS. What Should I Do Now?

Referral to a specialty center such as Children's is crucial.

As a parent, you will want to ensure proper treatment by a team of medical specialists who are experienced with the special needs of a child with this condition. This team includes surgeons, interventional radiologists, dermatologists, and nurse practitioners.

How Will Seattle Children's Diagnose KTS?

In many patients, a thorough medical history and physical exam are enough to make the diagnosis. However, a number of imaging (radiology) studies is useful when there are complications.

Evaluation of the deep venous system can be done by Doppler ultrasonography and magnetic resonance imaging (MRI) studies.

An MRI scan is also helpful in taking images of the soft tissue hypertrophy (cell and tissue enlargement). Angiography is especially helpful in the diagnosis of arteriovenous fistulae that are seen in the Parkes-Weber variant of KTS.

With the guidance from the imaging techniques, the affected limb will be watched and measured often to assess differences in limb length and to create a plan for prevention and treatment of overgrowth.

If the child's leg overgrowth is close to one inch, referral to a bone specialist is important.

How Will Seattle Children's Treat KTS?

Management of KTS depends upon individual symptoms.

Compression garments, like elastic tight-fitting socks, are often used for chronic vein insufficiency (low blood flow back to the heart), lymphedema and recurrent bleeding from capillary or vein malformations of the limb. They also protect the limb from trauma.

Pain medicine, antibiotics and elevating the limb are all used to manage swelling or inflammation of cells and tissue.

Anticoagulant therapy (the use of substances that prevent blood clotting) is needed in cases of clotting and is also used as a preventive measure before surgery.

Heel inserts are sometimes used to manage limb-length discrepancies that are less than one inch. For greater discrepancies, bone surgery may be considered.

Laser therapy is often quite effective in lightening the color of the port wine stain or treating areas of pain. Many treatments are typically required to achieve a desirable result. Laser treatment is also used when there is ulceration or open sores, since it tends to help with healing.

Surgical options are sometimes advised depending on individual circumstances. These include vein ligation (closing), vein stripping and vein resection:

  • Vein ligation is a procedure that clamps off a section of veins. The clamp prevents blood flow through the damaged section of veins and promotes blood flow through veins that are not damaged.
  • Vein stripping uses a metal wire to remove swellings from within the damaged vein.
  • Vein resection is a procedure that removes a section of veins from the body.

Sclerotherapy consists of injecting a chemical into the vein, causing inflammation. As the inner wall of the vein becomes inflamed, blood is not permitted to flow through it. The vein then collapses and forms scar tissue.