What is von Willebrand disease (VWD)?
Named after the doctor who discovered it, von Willebrand disease (VWD) is an inherited bleeding disorder that impacts the body’s ability to make blood clots. VWD is the most common inherited bleeding disorder.
Formation of blood clots depends on a process where proteins called clotting factors join platelets, a type of blood cell. With VWD, the body makes less von Willebrand clotting factor or it makes factor that doesn’t work the way it should.
Most people with VWD don’t experience severe bleeding. For people with a less common, more severe form of VWD who need ongoing treatment, therapy advances have made bleeding prevention more effective.
Von Willebrand disease types and von Willebrand factor
There are three types of VWD, depending on how von Willebrand factor is affected:
- Type 1: With Type 1, people still produce von Willebrand factor, but at lower amounts. It’s the mildest and most common form of the condition.
- Type 2: People with Type 2 make normal or below-normal amounts of von Willebrand clotting factor, but it doesn’t work correctly. The proteins might not be the right size, might try to start clotting too soon, or might not attach to platelets or other clotting factors. Each specific problem represents a subtype of Type 2. While many people with VWD Type 2 don’t need regular treatment, it’s important to find the subtype in case they do.
- Type 3: With this rarest type of VWD, people make very small amounts of von Willebrand clotting factor or none at all. Type 3 poses the greatest bleeding risk and often needs ongoing treatment.
Von Willebrand disease symptoms
Most people with VWD have a milder form. Symptoms may include easy bruising and prolonged nosebleeds or bleeding from injuries. Women with mild VWD can also experience heavy menstrual periods, which is why they tend to get diagnosed more often than men. Experts at Penn offer evaluations of heavy periods for people who may have VWD or another bleeding disorder.
People with less severe disease may still need to take precautions under special circumstances. These situations include medical and dental procedures and childbirth.
People with more severe VWD face a risk of significant bleeding from injuries. They may also experience bleeding for no apparent reason, a complication called spontaneous bleeding. Without treatment, bleeding can damage muscles or joints or harm the brain and other organs.
Causes of von Willebrand disease
VWD is most often inherited from a parent and is present at birth. Very rarely it is acquired, developing at some point in a person’s life. In such cases, VWD may be caused by diseases that affect the bone marrow or the immune system.
All people have two copies of the VWF gene — one from each parent. Changes to the VWF gene get passed along and can cause inherited VWD. How this inheritance takes place depends on the VWD type.
Von Willebrand disease diagnosis
Tests for VWD look at the blood’s ability to clot and how long the process takes, as well as the amount of von Willebrand clotting factor. While genetic testing can look for the inherited change responsible, it’s not always identified.
More severe VWD is often diagnosed in childhood. For other forms, you may get diagnosed in childhood or later in life. An older girl may get diagnosed after menstruation begins, for example. Or someone experiences an injury, has a medical procedure, or gets blood work done for an unrelated reason. Sometimes VWD is not discovered until adulthood.
Von Willebrand disease treatment
Doctors may prescribe certain medications when inherited VWD causes significant bleeding or to prevent bleeding with medical or dental procedures.
Drugs known as antifibrinolytics slow naturally occurring clots from breaking down, to help control bleeding. Another medication called desmopressin encourages the body to release more von Willebrand clotting factor. If that approach isn’t enough, you may need to inject replacement clotting factor.
Treatment for acquired VWD may target the cause of the disease.