Von Willebrand Disease
What is Von Willebrand Disease?
Von Willebrand Disease is a condition first described in 1926 by Dr. Erik Adolf Von Willebrand at the University of Helsinki in Finland. It is caused by low amounts or structural abnormalities in a protein called Von Willebrand Factor. This results in prolonged clotting and easy bleeding and bruising.
Von Willebrand Disease likely affects 1% of the US population (1 in every 100 people). The symptoms are often mild, and many people don't know they have it. Men and women are equally affected, but the condition is more common in Caucasians than other ethnic groups.
What are the Symptoms of Von Willebrand Disease?
Some people have no symptoms. The most common problem is mucocutaneous bleeding. This includes easy bruising, gum bleeding, nosebleeds, heavy menstrual periods, and unexpected bleeding after child birth and surgery. Most people with type 1 or type 2 disease will only have one or two of these symptoms. Type 3 disease results in spontaneous, severe and prolonged bleeding.
Two other conditions cause symptoms similar to type 1 and type 2 Von Willebrand Disease: platelet function disorders and collagen vascular diseases. Type 3 Von Willebrand symptoms are similar to those seen with hemophilia. In addition, problems unrelated to VWF and platelets can lead to mucocutaneous bleeding. Abnormal blood vessels and allergies may result in frequent nosebleeds, and hormonal disruption can cause heavy menstrual periods.
What Causes Von Willebrand Disease?
The Von Willebrand Factor (VWF) is a very large protein that helps platelets stick together and to injured blood vessel walls. This makes the protein critical for clot formation. Inherited genes result in low amounts of VWF (type 1 disease), abnormalities in the structure of VWF (type 2 disease) or the near absence of VWF (type 3 disease). Type 1 is most common and results in the mildest symptoms. Type 3 is rare, but severe.
How is Von Willebrand Disease Diagnosed?
Diagnosing Von Willebrand Disease can be difficult. There is no one test that definitively says yes or no to the diagnosis. Instead a panel of tests are run which look at how much VWF is present and how well it is working. Stress, health and physical activity may affect these numbers, so borderline results often need repeated to be sure of the diagnosis. The best place to get these tests run is a children's hospital laboratory with dedicated pediatric pathologists and hematologists to interpret the results.
Treatment Options for Von Willebrand Disease
The primary treatment for Von Willebrand disease is DDAVP. This is a hormone administered as a nasal spray or given through an IV. DDAVP stimulates clotting by releasing surplus VWF that is stored in the lining of blood vessels. The effect of a single dose of DDAVP usually lasts about twenty-four hours. DDAVP is not given every day, but reserved for times of severe nosebleeds, heavy menstrual periods, before dental and surgical procedures, and following traumatic injuries. In severe cases of abnormal bleeding or prior to major surgery, replacement VWF (Humate-P) can be given through an IV.
Complications Associated with Von Willebrand Disease
Complications from type 1 and type 2 Von Willebrand Disease are rare. However, significant trauma and head injury can result in abnormal bleeding into joints, the abdomen, and the brain, so medical attention following injuries is important. Complications are more common for kids with type 3 disease, and these kids should avoid contact sports and activities associated with a high likelihood of injury.
Type 1 and type 2 Von Willebrand Disease does not affect day-to-day life or life expectancy. Patients need to anticipate when problems could occur (surgery, dental procedures, menstruation, traumatic injury) and follow their doctor's advice on what to do in these situations.
There is no way to prevent Von Willebrand Disease. It is an inherited disorder and can not be prevented. At this time, there is no cure, but research in gene therapy may provide a cure for those with severe disease in the future.