What causes von Willebrand disease?
Von Willebrand disease (vWD) is caused by low levels of a blood-clotting factor called von Willebrand factor, and it helps blood to clot by acting as a kind of glue for platelets.
The von Willebrand factor is one of a dozen substances in the body that contribute to the coagulation of blood. Factors are often designated by Roman numerals.
What are the different types of von Willebrand disease?
There are three main types of vWD:
- Type 1—The most common and mildest form of vWD. Levels of von Willebrand factor are lower than normal, and the levels of factor VIII also may be reduced.
- Type 2—In type 2, the von Willebrand factor does not function the way it is supposed to. Type 2 vWD is divided into subtypes 2A, 2B, 2M and 2N. Each subtype is caused by different gene mutations and treated differently. This is why diagnosing the exact subtype is essential.
- Type 3—The rarest and most severe type. People with type 3 vWD have virtually no von Willebrand factor and low levels of factor VIII, which means they are likely to experience serious bleeding.
At the time of diagnosis, your child’s doctor will tell you which type she has and will outline the best options for vWD treatment.
Risk factors for vWD
The only risk factor for von Willebrand disease is a family history of this type of disorder. The gene responsible for the low levels of von Willebrand factor is inherited (passed down) from a parent. A parent with the gene for von Willebrand disease has a 50 percent chance of passing the gene on to his or her children.
What are the symptoms of von Willebrand disease?
Symptoms can vary a great deal depending on the type and severity of the disease. Many children with mild cases of von Willebrand disease have no visible symptoms. Others can experience symptoms such as:
- frequent large bruises from minor bumps or injuries
- frequent or prolonged nosebleeds
- heavy or prolonged menstrual bleeding in girls
- unusually prolonged or heavy bleeding from the gums during teeth-cleaning or other dental procedures
- unusually heavy bleeding after surgery
- blood in the urine or stools
- excessive bleeding from minor cuts
When to see a doctor
You should call your doctor if you notice any of the above symptoms in your child.