Parkes Weber Syndrome

Parkes Weber syndrome is a rare congenital (present at birth) vascular disorder. It involves a tangled network of irregular blood vessels. In diagnostic images, the cluster of tangled blood vessels looks like a tumbleweed. This blood vessel cluster has a hard time circulating blood to areas that rely on it for their blood (and oxygen) supply.

This syndrome typically affects only one limb (usually one leg). This limb may develop skin ulcers (open sores) from a lack of oxygen. This type of wound is hard to heal due to a lack of blood supply.

Complications of Parkes Weber syndrome can be life-threatening. But regular monitoring helps catch issues that develop over time. Providers have many treatments they can use to help ease symptoms and slow the disease down.

What are the symptoms?

Parkes Weber syndrome symptoms and signs may show up at birth or during childhood. Symptoms include pain, swelling and fatigue in the affected area, usually in one leg.

Signs of Parkes Weber syndrome include:

• Capillary malformations: These appear as salmon-colored port wine stains with pale halos around them on your skin.
• Arteriovenous malformations (AVMs): These blood vessel tangles can happen anywhere in your body, but are often in one leg (or sometimes one arm).
• Hemihyperplasia: This is a noticeable difference in the size of one limb because of more bone and soft tissue growth than in the other limb.

This condition is like Klippel-Trenaunay syndrome, which has venous malformations and purple port wine stains.

What causes Parkes Weber syndrome?

A variation in your RASA1 gene can cause Parkes Weber syndrome. This gene plays a role in how your vascular system develops. You may inherit this variation from one biological parent. But it can also happen at random (without a biological family history).

Complications of Parkes Weber syndrome

High-output heart failure is a serious complication of this condition. This can lead to an enlarged heart and pulmonary edema (fluid buildup in your lungs). Skin infections from skin ulceration are common and require treatment.

Other complications may include:

• Skin ulcers (wounds)
• Rhabdomyolysis (muscle breakdown that can be life-threatening)
• Heart disease
• Hypertrophy (heart muscle thickening)
• Tachycardia (an abnormally high heart rate while at rest)
• High blood pressure
• Limb ischemia (low blood flow to your limb)
• Aneurysms (weakness in an artery wall)
• Blood clots (mass of blood cells)
• Varicose veins

How is it diagnosed?

It may be difficult to get a Parkes Weber syndrome diagnosis because the condition is rare. But a provider may suspect your child has it based on what they see in a physical exam. A provider may talk about different syndrome stages, from I to IV. Stage I usually doesn’t have symptoms. Stages II through IV include symptoms, with IV being the worst.

Tests to diagnose Parkes Weber syndrome may include:

• Doppler ultrasound
• CT (computed tomography) scan
• CT angiogram
• MRA (magnetic resonance angiogram)
• MRI (magnetic resonance imaging)

How is it treated?

Providers don’t have a cure for Parkes Weber syndrome. But treatments can ease symptoms and keep the syndrome from getting worse. Parkes Weber syndrome treatment varies from person to person. Treatments range from simple, noninvasive measures to procedures that destroy blood vessels.

Treatments may include:

• Compression stockings to reduce swelling and prevent deep vein thrombosis
• Orthopedic shoe insert for one foot to make up for the difference in leg length
• Wound care for skin ulcers
• Angiogenesis inhibitors to keep new blood vessels from forming
• Diuretics to reduce fluid buildup
• Stent to hold a blood vessel open
• Embolization of AVMs (creating a blockage inside a blood vessel)
• Endovascular ablation of AVMs (destroying them with a minimally invasive procedure)
• Sclerotherapy of AVMs (an injection to close off a blood vessel)
• Surgery
• Amputation (limb removal)

What can I expect if my child has Parkes Weber syndrome?

Parkes Weber syndrome is a chronic (long-term) condition. Vascular malformations tend to become more noticeable over time. And your child may develop more port wine stains as they age.

Some people need a hospital stay to treat bleeding or infected ulcers.

Embolization and other treatments can improve circulation. But your child will most likely need treatment more than once for an AVM. This is a condition that requires lifelong follow-ups.

What is the outlook for Parkes Weber syndrome?

Because the disease is rare, information about a Parkes Weber syndrome prognosis is limited. One study included a few people who had their first treatment in their 40s and even late 60s. Most of the others in that study had their first treatments before age 17. This suggests that most people need treatment during childhood.

Can Parkes Weber syndrome be prevented?

Because this syndrome is present at birth, you can’t prevent it. You can talk with a genetic counselor if Parkes Weber syndrome runs in your family and you’re planning a pregnancy. But the syndrome can happen even if you don’t have a biological family history of it.

How do I take care of my child?

Having a child with Parkes Weber syndrome means being extra observant. In addition to watching for typical childhood illnesses, it’s important to keep an eye out for signs that the syndrome is getting worse. Your child’s healthcare providers can help you monitor any changes in their condition.

Helping your child stay at a weight that’s healthy for them may help with their symptoms, as well.

When should my child see their healthcare provider?

The short answer is: regularly. A team that specializes in vascular issues may be the best bet for your child. You’ll likely need to take your child to regular checkups with several providers, like a:

• Dermatologist
• Interventional radiologist
• Hematologist or oncologist
• General surgeon

Your child may have regular tests like echocardiograms or MRIs to check for complications. They should see their provider whenever they have painful swelling in the affected area.

When should I take my child to the ER?

Seek immediate treatment for your child if they’re having:

• Skin breakdown or ulcers
• Chest pain
• Heart palpitations
• Shortness of breath (dyspnea)
• Dizziness
• Muscle weakness, pain or stiffness

What questions should I ask my healthcare provider?

Questions to consider asking your child’s provider may include:

• How often do they need checkups?
• What stage of the syndrome does my child have?
• What’s the best treatment for them?
• Which treatments have worked well for others with this syndrome?