How Is von Willebrand Disease Diagnosed?

Early diagnosis of von Willebrand disease (VWD) is important to make sure that you’re treated and can live a normal, active life.

VWD is sometimes difficult to diagnose. People with type 1 or type 2 VWD may not have major bleeding problems. As a result, they may not be diagnosed until they have heavy bleeding after surgery or some other trauma.

On the other hand, type 3 VWD can cause major bleeding problems during infancy and childhood. As a result, children with type 3 VWD are usually diagnosed during their first year of life.

To find out if you have VWD, your doctor will review your medical history and the results from a physical exam and tests.

Medical History

Your doctor will likely ask questions about your medical history and your family’s medical history. He or she may ask about:

• Any bleeding from a small wound that lasted more than 15 minutes or started up again within the first 7 days following the injury.
• Any extended, heavy, or repeated bleeding that required medical attention after surgery or dental extractions.
• Any bruising with little or no apparent trauma, especially if you could feel a lump under the bruise.
• Any nosebleeds that occurred for no apparent reason and lasted more than 10 minutes despite pressure on the nose, or any nosebleeds that needed medical attention.
• Any blood in your stools for no apparent reason.
• Any heavy menstrual bleeding (for women). This bleeding usually involves clots or lasts longer than 7 to 10 days.
• Any history of muscle or joint bleeding.
• Any medicines you've taken that might cause bleeding or increase the risk of bleeding. For example, aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), clopidogrel (Plavix^®), warfarin, or heparin.
• Any history of liver or kidney disease, blood or bone marrow disease, or high or low blood platelet counts.

Physical Exam

The doctor also will do a physical exam to look for unusual bruising or other signs of recent bleeding. He or she also will look for evidence of liver disease or anemia.

Diagnostic Tests

No single test can diagnose VWD. Your doctor will order a combination of blood tests to diagnose the disease. These tests may include:

• Von Willebrand factor antigen. This test measures the amount of von Willebrand factor in your blood.
• Von Willebrand factor ristocetin (ris-toe-SEE-tin) cofactor activity. This test shows how well the von Willebrand factor works.
• Factor VIII clotting activity. Some people with VWD have low levels of factor VIII activity, while others have normal levels.
• Von Willebrand factor multimers. This test is done if one or more of the first three tests are abnormal. It shows the makeup or structure of the von Willebrand factor. It helps your doctor diagnose what type of VWD you have.
• Platelet function test. This test measures how well your platelets are working.

Your doctor may order these tests more than once to confirm the diagnosis. He or she may also refer you to a hematologist (a doctor who specializes in treating blood diseases) to confirm the diagnosis and for followup care.