What is von Willebrand Disease (VWD)?
Von Willebrand disease (VWD – also known as von Willebrand disorder) is a bleeding disorder that affects both males and females.
People with VWD have a problem with a clotting protein in their blood called von Willebrand factor (VWF) that works with another protein factor VIII (8) to help control bleeding. They do not have enough VWF or it doesn’t work the way it should. As a result it takes longer for blood to clot and for bleeding to stop.
How common is VWD?
VWD is the most common hereditary bleeding disorder worldwide. It is estimated that 1 in 1,000 people have a form of VWD that needs medical treatment.
Most people with VWD are born with the disorder as VWD is usually inherited genetically. Sometimes VWD will show up when the person is a child. Others don’t find out until they are adults and have a bleeding problem, or until a relative is diagnosed and it is suggested that they are tested as well.
Many people with VWD may not know they have the disorder because they may not have bleeding problems needing medical treatment very often. VWD can also be difficult to diagnose accurately and testing and diagnosis needs to be done by specialists with experience in VWD. More than 2,500 people have been diagnosed with VWD in Australia, but research suggests that many others are not yet diagnosed.
There are also severe forms of VWD, but these are rare.
It is important to remember that there can be bleeding problems with all forms of VWD and any bleeding that occurs with VWD needs to be assessed and treated.
Types
There are three main types of von Willebrand disease. Bleeding symptoms can vary from person to person within each type. It is important to know which type of VWD a person has to make sure they receive appropriate treatment.
- Type 1 VWD is the most common form. Around 80% of all people with VWD have this form. In type 1 VWD, the von Willebrand Factor (VWF) works normally, but there is not enough of it. Symptoms are usually mild, depending on the level of VWF in the blood. However, some people with type 1 can have very low levels of VWF and have severe bleeding problems.
- Type 2 VWD is divided into subtypes 2A, 2B, 2M and 2N. Certain subtypes may be treated differently, which makes knowing the exact type of VWD you have very important. In type 2 VWD, the amount of VWF in people’s blood is often normal but the VWF doesn’t work properly.
- Type 3 VWD is very rare. People with type 3 VWD have very little or no VWF in their blood. Bleeding can occur more often, be more severe and can also include joint and muscle bleeding.