People with von Willebrand's disease either lack, or have ineffective supplies of, a substance in the blood called von Willebrand factor (vWF). This promotes clotting.
People with the condition will have difficulty forming blood clots. For example, if they cut themselves, it will take longer to stop bleeding.
It occurs in up to 1 percent of people in the United States. No cure is available, but treatment can help people with the condition lead otherwise healthy lives.
In this article, we look at the different types of von Willebrand's disease, their symptoms, and ways to manage them.
Von Willebrand's disease can lead to frequent, intense nosebleeds.
There are four main types of von Willebrand's disease.
Type 1 is the most common. About 60–80 percent of people with von Willebrand's disease have type 1.
Type 1 is characterized by low levels of vWF. Clotting factor VIII, another essential blood-clotting protein, may also be affected. The severity of type 1 can range from mild to severe, but it mostly presents as mild.
Several subtypes might occur in type 2 von Willebrand's disease, but a doctor will generally diagnose type 2 when the vWF does not work properly, rather than there being a lack of it.
Different gene mutations can cause type 2, and each will require different treatment. Knowing the type 2 subtype can help a doctor shape treatment in a way that works best for the individual.
Type 2 is present in around 15–30 percent of people who have von Willebrand's disease.
In type 3, the individual typically has little to no vWF at all. This is the rarest and most severe form of von Willebrand's disease.
Around 5–10 percent of people with the condition have type 3.
While the more common types of von Willebrand's disease are inherited, it is also possible to develop the condition from an autoimmune disease such as lupus or cancer, or as a result of taking some medications.
This is called acquired von Willebrand's disease.
Signs and symptoms may be mild and difficult to observe, or they may occur in a range of ways. It is difficult for doctors to diagnose milder forms of von Willebrand's disease.
When symptoms do appear, they tend to include bruising and extended or excessive bleeding. Bleeding might occur around the mucous membranes, including the gastrointestinal tract.
Symptoms of bleeding include:
- nosebleeds, which may be prolonged, recurring, or both
- bleeding from the gums
- longer, heavier menstrual bleeding
- excessive bleeding from a cut
- excessive bleeding after a tooth extraction or other dental work
- bruising, sometimes with lumps forming under the skin
Sometimes, a doctor will only discover the condition after the person has undergone a surgical procedure, had dental work, or experienced serious trauma.
Women may notice the following signs when menstruating:
- blood clots that are at least 1 inch in diameter
- soaking through at least two tampons or pads in 2 hours
- a need for double sanitary protection to control bleeding
- menstruation that continues for over a week
- symptoms of anemia, including fatigue, pallor, and drowsiness
In rare and severe cases, the bleeding can damage internal organs. When internal organ damage occurs as a result of this condition, it can be fatal.
Risk factors and causes
When injury occurs in a blood vessel, small fragments inside a type of blood cell called platelets normally clump together to plug the wound and stem the bleeding.
vWF, which carries clotting factor VIII, helps platelets stick together to form a clot. Clotting factor VIII is either missing or faulty in people with the most common form of hemophilia.
Family history is the most common risk factor for von Willebrand's disease. That said, the genetic content needed for each type to develop will differ.
For example, in types 1 and 2, only one gene is necessary to cause the condition. Also, the biological parents will likely have von Willebrand's disease themselves.
In type 3, both parents need to pass on genes, and they will most likely be carrying the disease without actually having it.
Acquired von Willebrand's disease can happen later in life, so advanced age is a factor.
Blood tests can give a clear picture of how the blood clots.
Early diagnosis and treatment significantly increase the chances of living a normal and active life with von Willebrand's disease.
Some people with type 1 or type 2 may not experience major bleeding problems. Therefore, they may not receive a diagnosis until they have surgery or a serious injury.
The diagnosis of type 3 usually occurs at an early age, because major bleeding will probably occur at some time during infancy or childhood.
A doctor will look at the person's medical history, carry out a physical exam, and run some diagnostic tests.
When assessing medical history, the doctor may ask whether the person has ever experienced the following symptoms:
- excessive bleeding after surgery or a dental procedure
- unexpected or easy bruising, or bruising with a lump underneath
- blood in the feces
- bleeding in the joints or muscles
- bleeding after taking medications, such as aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), or blood thinners
- abnormal blood platelet counts
- unexplainable nosebleeds that last for longer than 10 minutes, even after placing pressure on the nose
- frequent nosebleeds
- heavy menstrual bleeding for longer than a week, with clots
- kidney, liver, blood, or bone marrow disease
The physical exam will check for bruising and signs of recent bleeding.
Blood tests can assess:
- vWF levels
- the structure of vWF and its multimers, or protein complexes, as well as how its molecules break down, to determine the type of von Willebrand's disease
- ristocetin cofactor activity, to reveal how well vWF works and whether it is adequately clotting the blood
- factor VIII clotting activity, to establish levels of factor VIII
- platelet function
- bleeding time, to see how long it takes for a small wound to stop bleeding
It may take 2–3 weeks for the test results to come back, and some tests may need repeating to confirm a diagnosis. The doctor may refer the individual to a hematologist, a doctor who specializes in diseases of the blood.
No cure is currently available for von Willebrand's disease, but some options can prevent or stop bleeding episodes. Treatment tends to take the form of medication.
Symptoms are normally mild, and treatment for people with milder symptoms is only necessary during surgery, dental work, or after an accident or injury.
Management methods depend on the type and severity of the condition, as well as the person's response to therapy.
- release more vWF and factor VIII into the bloodstream
- control heavy menstruation
- prevent the breakdown of blood clots
- replace missing vWF
Desmopressin (DDAVP) is a synthetic hormone that a person can take by injection or through a nasal spray (Stimate). It is similar to vasopressin, which is a natural hormone that controls bleeding by making the body release more of the vWF already present in the linings of blood vessels. This raises factor VIII levels.
A doctor will usually prescribe this for those with types 1 and 2. They may use the nasal spray at the beginning of a menstrual period or before minor surgery.
If DDAVP is not sufficient, the doctor might prescribe doses of concentrated blood-clotting factors containing vWF and factor VIII for all three types of von Willebrand's disease.
Clot-stabilizing medications delay the breakdown of clotting factors. A doctor may call these antifibrinolytic drugs. They help keep a clot in place once it forms, especially during surgery or dental work.
A doctor may also apply fibrin sealant to a wound to stop the bleeding. This is a glue-like substance.
vWF and factor VIII levels tend to rise during pregnancy, but bleeding complications might occur during delivery. Bleeding may be heavier and last longer after giving birth.
Women who have a type of von Willebrand's disease should consult a hematologist and specialized obstetrician when they become pregnant.
They will likely carry out blood tests during the final trimester of pregnancy.
Preventing bleeding episodes
Some medicines affect blood clotting. Speak to a doctor before taking some OTC medications.
To prevent bleeding episodes, people who have any type of von Willebrand's disease should check with a physician before taking medications.
They should also avoid over-the-counter (OTC) medications that may affect blood clotting, such as aspirin, ibuprofen, and other NSAIDs.
It may also be worth a person informing healthcare professionals such as dentists about their condition, as well as sports coaches or people who oversee physical activity.
People with severe symptoms should also wear a medical ID necklace or bracelet.
To minimize common health risks, people with the condition should eat a healthful, balanced diet and exercise regularly. Normally, von Willebrand's disease does not interfere with daily activities, but doctors may recommend that children with the condition avoid contact sports, such as football and hockey.
Von Willebrand's disease is the most common type of heritable bleeding disorder. Type 1 is the most prevalent, affecting around 60–80 percent of all people with the condition.
Symptoms may be mild or severe, and they may include nosebleeds, excessive bleeding from a cut, and bruising more easily.
Though no cure is currently available for von Willebrand's disease, treatments tend to include taking medications that prevent the breakdown of blood clots and applying a glue-like substance called fibrin sealant to bleeding wounds.
What is the difference between von Willebrand’s disease and hemophilia?
While von Willebrand’s disease and hemophilia are both genetic and cause problems with blood clotting, they are distinctly different conditions.
Von Willebrand’s disease is usually milder than hemophilia and is more common. It affects males and females equally, while hemophilia almost always affects males.
Hemophilia causes low levels of clotting factors that are different than the vWF involved in von Willebrand’s disease.