Von Willebrand Disease - Article Immune Thrombocytopenic Purpura
Article: Von Willebrand Disease
What Is von Willebrand Disease?
Von Willebrand disease is an inherited bleeding disorder. Children born with the disease have one or both of the following:
- Low levels of a protein that helps the blood to clot, or
- The protein does not work as it should.
This clotting protein is called von Willebrand factor. When some of this factor is missing or defective it can cause prolonged bleeding after an injury or accident.
What is 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. Clotting is your body's reaction to bleeding to keep 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?
Certain proteins in your blood help the blood to clot. Von Willebrand factor is one of those proteins. It is made by the lining of cells in the wall of blood vessels (veins and arteries). 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 that helps the platelets stick together. Von Willebrand factor is also a carrier of clotting factor VIII, another protein that helps your blood to clot.
Types of von Willebrand Disease
There are three major types of von Willebrand disease:
- Type 1: A low level of the von Willebrand factor. Levels 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 of all people with von Willebrand disease have Type 1.
- Type 2: Due to a defect, the von Willebrand factor does not work as it should. Type 2 is divided into 2A and 2B. Each is treated differently so it is important to know the exact type.
- Type 3: People with this type usually have no von Willebrand factor and low levels of factor VIII. Type 3 is severe and very rare.
What Causes von Willebrand Disease?
Von Willebrand disease is almost always inherited. This means that parents pass a gene for the disease on to their children. The gene for the disease is usually dominant. That means that a parent with the disease has a 50 percent or 1 in 2 chance of passing the gene to each of his or her children. Type 1 and Type 2 von Willebrand disease are usually inherited this way.
The gene for Type 3 von Willebrand disease is usually recessive. That means the child would have to inherit the gene from both parents. Even if both parents have mild or no symptoms, the child can have severe symptoms.
In rare cases, von Willebrand disease can be acquired (developed later in life).
Who Gets von Willebrand Disease?
Von Willebrand disease is the most common inherited bleeding disorder. It occurs in about 1 in every 100 to 1,000 people. Unlike hemophilia, another inherited bleeding disorder that occurs mostly in males, von Willebrand disease occurs equally in males and females.
Parents pass the disease to their children through a gene. One or both parents can pass the gene to their children. This is true even for parents who do not have bleeding symptoms.
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 do not have bleeding symptoms.
Patients with Type 1 and Type 2 disease may have the following mild to moderate bleeding symptoms:
- Easy bruising
- Bleeding from the gums after a dental procedure
- Heavy menstrual bleeding in women
- Blood in their stools (from bleeding in the intestines or stomach)
- Blood in their urine (from bleeding in the kidneys or bladder)
- Excessive bleeding after a cut or other accident
- Excessive bleeding after surgery.
Heavy menstrual bleeding is the most common symptom in women. If untreated, it can lead to iron deficiency and anemia. Doctors usually test for the disease in women who have heavy menstrual bleeding. Some people may only be diagnosed after an episode of prolonged bleeding after an accident or surgery.
Patients with Type 3 disease (rare and severe) are usually diagnosed in childhood. They may have:
- Any of the symptoms listed above.
- Severe bleeding episodes for no reason. These bleeding episodes can be life threatening without immediate treatment.
- Bleeding into soft tissues or joints, causing severe pain and swelling. Bleeding into the joint is called hemarthrosis.
How is von Willebrand Disease Diagnosed?
Von Willebrand disease is sometimes difficult to diagnose. Mild symptoms may be mistaken for other illnesses. Specific tests for the disease must be done because some people with a mild form of the disease (Type 1) may have normal results on the usual test for bleeding disorders. If you have bleeding symptoms, your doctor will order blood tests that specifically check:
- The ability of your blood to clot
- The level of von Willebrand factor in your blood
- How well the von Willebrand factor works
These tests should be repeated several times in order to be sure of the diagnosis.
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 may not have significant bleeding problems and may not be diagnosed until adulthood.
Your doctor will order a combination of blood tests to diagnose the disease. These tests may include:
- Von Willebrand factor antigen. This test measures the amount of von Willebrand factor in your blood.
- Ristocetin (ris-too-SEE-tin) cofactor activity. This test shows how well the von Willebrand factor works.
- Test for factor VIII clotting activity. Some people with von Willebrand disease will have low levels of factor VIII activity, while others will have normal levels.
- Von Willebrand factor multimers. This test shows the makeup or structure of the von Willebrand factor. It helps your doctor diagnose what type of disease you have.
- Platelet function test. This test measures how well your platelets are working.
How is von Willebrand Disease Treated?
Most cases of von Willebrand disease are mild and often do not require treatment. Treatment may only be needed after a surgery, tooth extraction, or an accident. For those who need treatment, one or more of the following may be used:
- Medication to increase the production of the von Willebrand factor
- Medication to prevent breakdown of clots
- Medication to control heavy menstrual bleeding in women
- Injection of clotting factor concentrates (containing von Willebrand factor and factor VIII).
Your doctor will decide what treatment you need based on the severity and the type of disease your have. Specific treatments include:
- Desmopressin (DDAVP) is a synthetic hormone usually given by injection or nasal spray. It works by making the body produce more von Willebrand factor, which also increases the level of factor VIII activity. DDAVP is effective in treating most patients with Type 1 disease and some with Type 2a disease.
- Replacement therapy is the injection of a concentrate of von Willebrand factor and factor VIII. This treatment can be used in:
- Patients who cannot take DDAVP or who need prolonged treatment
- Patients with Type 1 disease who do not respond to DDAVP
- Patients with Type 2b disease
- Patients with Type 3 disease.
- Oral contraceptives (or birth control pills) can help women who have heavy menstrual bleeding. The hormones in the pills can increase von Willebrand factor and factor VIII activity.
- Antifibrinolytic drugs help prevent the breakdown of clotting factors in the blood. They are used mostly in von Willebrand patients to stop bleeding following minor surgery, tooth extraction, or an injury. They may be used alone or together with DDAVP and replacement therapy.
- Fibrin glue is medicine placed directly on a wound to stop the bleeding.
Living with von Willebrand Disease
It is important that you try to prevent bleeding and stay healthy. You should:
- Avoid over-the-counter medications that can affect the clotting process:
- Aspirin and other drugs that contain salicylates
- Other nonsteriodal anti-inflammatory drugs
- Always check with your doctor before taking any medication.
- Tell your doctor or dentist that you have von Willebrand disease. You can receive medication before dental work that reduces bleeding.
- Wear a medical ID bracelet so that in case of serious injury or accident, the doctors caring for you will know about your disease.
- Exercise regularly and maintain a healthy weight. Exercise helps keep muscles flexible and helps prevent damage to muscles and joints. Always stretch before exercising. Some safe exercises or activities are swimming, biking, and walking. Football, hockey, wrestling, and weightlifting (heavy weights) are not safe activities if you have had bleeding problems. Always check with your doctor before starting any exercise program.
Frequently Asked Questions
Is there a cure for von Willebrand disease?
No, von Willebrand disease is a lifelong disorder. Most people have a mild form of the disorder that causes little or no change in their lives.
Who should know that I have von Willebrand disease?
Adults should be sure that persons such as their doctor, dentist, employee health nurse, gym trainer, and sports coach are aware of their disorder. You should wear a medical ID bracelet stating that you have von Willebrand disease. In case of an accident or emergency, this will be very helpful to the health care team treating you.
Who should know that my child has von Willebrand disease?
It is important that anyone who will be responsible for your child know about his or her disorder. For example, the school nurse, teacher, daycare provider, coach, or any leader of any after-school activity should know that your son or daughter has von Willebrand disease.
Why is this condition called von Willebrand disease?
A man named Erik von Willebrand discovered the disease in 1925. The disease was named after him.
Is von Willebrand disease life threatening?
Most people with von Willebrand disease have a mild form, which usually does not cause bleeding that is life threatening. But any bleeding that cannot be controlled can be life threatening. Rarely, people with severe forms of von Willebrand disease will need to seek immediate emergency treatment to stop life threatening bleeding.
Do all people who have the gene for von Willebrand disease have bleeding problems?
No. Many people carry the genes for the disease but do not have bleeding symptoms. Even though they do not have symptoms, they can still pass the disease on to their children. How will I know if I have von Willebrand disease?
If you or anyone in your family has a history of bleeding, your doctor will use a number of blood tests to find out whether or not you have the disease. These tests will check how quickly your blood clots and the levels of clotting factors in your blood. Your doctor will use these test results to diagnose your bleeding disorder.
Von Willebrand disease is the most common inherited bleeding disorder.
People with von Willebrand disease may have low levels of or a defective clotting protein in their blood. This clotting protein is called von Willebrand factor.
Low levels of clotting factors or factors that do not work correctly can slow the process to stop bleeding after an injury.
Von Willebrand disease is an inherited disorder. This means that it is passed down from parent to child.
Von Willebrand disease affects men and women equally.
The signs and symptoms of von Willebrand disease depend on the type you have. Most cases of von Willebrand disease are mild.
Blood tests are used to diagnose von Willebrand disease. These tests check how long it takes for your blood to clot, your level of von Willebrand factor, and how well the von Willebrand factor in your blood is working.
There are three types of von Willebrand disease:
- Type I is the most common and mildest form of the disease
- Type II is usually a mild-to-moderate form of the disease
- Type III is very rare and is the most severe form of the disease.
Doctors use medicines and factor replacement therapy to treat the disease.
Once the type of von Willebrand disease is diagnosed, your doctor will determine what treatment you will need. The severity of your symptoms will also determine what treatment is best for you.
It is important to follow your treatment plan and see your doctor regularly. Contact your doctor if you have any questions or concerns.
Source: National Heart, Lung and Blood Institute
Cache Date: December 10, 2004
- Abnormal Uterine Bleeding - ACOG Publication #AP095 (American College of Obstetricians and Gynecologists (ACOG) Resource Center)
- aPTT (American Association for Clinical Chemistry)