Von Willebrand Disease

• In Type 1 (70-80%), the level of von Willebrand factor (vWF) in the blood is reduced. Although the condition can be made worse by taking aspirin and other nonsteroidal anti-inflammatory drugs, the symptoms might be so mild that the person isn't ever diagnosed. People with Type I vWD usually do not bleed spontaneously, but they can have significant bleeding with trauma, surgery, or when they have a tooth pulled.
• In Type 2 (15-20%), of which there are 5 subtypes, the building blocks that make up the vWF (called multimers) are smaller than usual or break down too easily. Type 2 vWD can be either autosomal dominant or recessive.
• Type 3 (autosomal recessive) patients have severe bleeding problems and have no measurable von Willebrand factor and factor VIII (the protein that helps with blood clotting).
• Aquired type – vWD can occur in those with Wilms tumor, Congenital heart disease, Systemic lupus erythematosus and Hypothyroidism

What does it look like?

• bruising that is unusual in location or frequency
• abnormal menstrual bleeding
• bleeding in the mucous membranes, such as the gums, nose, and lining of the gastrointestinal system
• excessive or prolonged bleeding after a tooth is pulled or tonsils are removed or prolonged oozing from cuts
• The rare type 3 vWD can manifest with severe bleeding symptoms similar to severe hemophilia (eg, bleeding in joints or muscles).
• Family history of a bleeding tendency - bleeding from wounds, gingival bleeding, postpartum bleeding

Because the symptoms can be mild, vWD can be difficult to diagnose and often goes undetected. Many children are diagnosed as a result of a positive family history or during routine preoperative screening (eg. prolonged bleeding time).

The tests to diagnose vWD may include:

• bleeding time
• factor VIII level test (also called factor VIII coagulant) - measures the level of factor VIII and its ability to function
• vWF antigen test (also called factor VIII antigen) - measures the amount of von Willebrand factor. The disorder is considered mild if a person has 20% to 40% of the normal amount. It is severe if the amount is less than 10% of normal.
• vWF activity (ristocetin cofactor activity test ) - measures how well the von Willebrand factor is working
• vWF multimers analysis - helps classify the type of vWD
• platelet function tests - determine how well the platelets work and help identify the type of vWD or the presence of another disorder

Tests may need to be done more than once because these levels may rise and fall over time in an individual.

The most common treatment for von Willebrand disease is desmopressin. This medication causes a temporary increase in the von Willebrand factor levels by causing release of vWF from blood vessel storage sites. It can be given intravenously or intranasally (into the nose), but may be ineffective in some Type 2 and all Type 3 patients. Patients with Type 3 (and some Type 2) will need intravenous treatment with Factor VIII concentrates that contains both factor VIII and von Willebrand factor in high molecular weight form. Patients with Type 1 may also require the use of this medication in certain situations, such as major trauma or major surgery although they can generally be treated with desmopressin. No evidence suggests that extensive activity restrictions are necessary for most patients with mild type1 vWD. Patients with more severe forms of vWD should follow guidelines developed for patients with severe hemophilia. Avoid medications with known antiplatelet effects such as aspirin, ibuprofen and naproxen. Heavy menstrual bleeding can sometimes be controlled with birth control pills. Call your child's doctor immediately if your child experiences any excessive or unexplained bleeding.