Von Willebrand disease
Von Willebrand disease is an inherited bleeding disorder. The disease is named after the doctor who discovered it, Erik von Willebrand. People born with the disease have one or both of the following:
What is blood clotting?An injury, like a cut, to a blood vessel causes a complex chain of events called the clotting process, which results in a blood clot. Blood clotting is your body's reaction to bleeding; it keeps you from losing too much blood. Losing too much blood can be life threatening and can damage your internal organs.
What is von Willebrand factor?Von Willebrand factor is one of the proteins in your blood that helps it to clot. The cells that line the walls of your blood vessels (veins and arteries) make von Willebrand factor. When blood vessels are damaged, platelets (small blood cells that collect and stick together to plug cuts and breaks in blood vessels) clump together at the site of the injury. Von Willebrand factor acts like glue and helps the platelets stick together. Von Willebrand factor also carries and stabilizes clotting factor VIII, another protein that helps your blood to clot.
OutlookVon Willebrand disease is a lifelong disorder. Most people with von Willebrand disease have a mild form of the disorder, which usually doesn't cause life-threatening bleeding and often doesn't require treatment. If treatment is needed, medicines and medical therapies are used.
Types of von Willebrand disease
Type 1In type 1 von Willebrand disease, there is a low level of von Willebrand factor. The level of factor VIII may also be lower than normal. This is the mildest and most common form of the disease. About 3 out of 4 people diagnosed with von Willebrand disease have type 1.
Type 2In type 2 von Willebrand disease, a defect in von Willebrand factor causes it to not work properly. Type 2 is divided into 2A, 2B, 2M, and 2N. Each is treated differently, so knowing the exact type is important.
Type 3People with type 3 von Willebrand disease usually have no von Willebrand factor and very low factor VIII. Type 3 is severe and very rare.
What causes von Willebrand disease?Von Willebrand disease is usually inherited – that is, passed in the genes from parent to child. Genes are located in the cells of the body and control how the cells make proteins, such as von Willebrand factor. Each cell in the body has two copies of every gene (except some genes related to gender). You inherit one copy from your mother and one from your father.
In a person with von Willebrand disease, one or both of the genes that control the production of von Willebrand factor are defective. Type 1 and type 2 von Willebrand disease can develop if a person inherits one copy of the defective gene from one parent and a normal copy of the gene from the other. Type 1 and type 2 von Willebrand disease also can develop if the person inherits a defective copy of the gene from both parents. Type 3 von Willebrand disease develops only if a person inherits a defective von Willebrand gene from both parents.
In rare cases, von Willebrand disease isn't inherited, but develops due to other reasons later in life. This is called acquired von Willebrand syndrome.
Who is at risk for von Willebrand disease?Von Willebrand disease is the most common inherited bleeding disorder. It occurs in children who inherit one or two defective von Willebrand genes from their parents.
Mild defects in von Willebrand factor that occasionally cause bleeding occur in about 1 in every 100 to 1,000 people. Significant bleeding from von Willebrand disease occurs in about 1 in every 10,000 people. Unlike hemophilia, another inherited bleeding disorder that occurs mostly in males, von Willebrand disease occurs equally in males and females.
What are the signs and symptoms of von Willebrand disease?The signs and symptoms depend on the type and severity of the disease. Some people have the gene for the disease but don't have bleeding symptoms.
People with type 1 and type 2 von Willebrand disease may have the following mild-to-moderate bleeding symptoms:
Doctors may test for von Willebrand disease in women who have unusually heavy menstrual bleeding. Some people may only be diagnosed after an episode of prolonged bleeding after an accident or surgery.
People with type 3 von Willebrand disease (rare and severe) are usually diagnosed in childhood. They may have:
How is von Willebrand disease diagnosed?Von Willebrand disease is sometimes difficult to diagnose. Mild symptoms may be mistaken for other illnesses. Severe von Willebrand disease can cause significant bleeding problems during infancy. Because of this, people with severe von Willebrand disease are usually diagnosed during the first year of life. People who have milder forms of the disease may not have significant bleeding problems, or they may have mild bleeding symptoms. People with milder forms of von Willebrand disease may not be diagnosed until adulthood.
Your doctor will review your personal and family history for signs and symptoms that indicate a bleeding disorder, including von Willebrand disease. Your doctor also may order laboratory tests.
If your doctor thinks that you have von Willebrand disease, specific tests must be done because some people with a mild form of the disease (type 1) may have normal results on the usual tests for bleeding disorders. If you have bleeding symptoms, your doctor will order blood tests that specifically check:
Your doctor will order a combination of blood tests to diagnose the disease. These tests may include:
How is von Willebrand disease treated?Most cases of von Willebrand disease are mild and often don't require treatment. Treatment may only be needed to prevent or treat bleeding associated with surgery, tooth extraction, or an accident. For those who need treatment, one or more of the following may be used:
Living with von Willebrand diseasePreventing bleeding and staying healthy are important. If you have von Willebrand disease, you should:
Related category• HEALTH AND DISEASE
Source: U.S. National Heart, Lung and Blood Institute
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