Diagnosis

Mild forms of von Willebrand disease can be difficult to diagnose because bleeding is common, and, for most people, doesn't indicate a disease. However, if your doctor suspects you have a bleeding disorder, he or she might refer you to a blood disorders specialist (hematologist).

To evaluate you for von Willebrand disease, your doctor will likely ask you detailed questions about your medical history and check for bruises or other signs of recent bleeding.

Your doctor will also likely recommend the following blood tests:

• Von Willebrand factor antigen. This determines the level of von Willebrand factor in your blood by measuring a particular protein.
• Von Willebrand factor activity. There are a variety of tests to measure how well the von Willebrand factor works in your clotting process.
• Factor VIII clotting activity. This shows whether you have abnormally low levels and activity of factor VIII.
• Von Willebrand factor multimers. This evaluates the structure of von Willebrand factor in your blood, its protein complexes and how its molecules break down. This information helps identify the type of von Willebrand disease you have.

The results of these tests can fluctuate in the same person over time due to factors such as stress, exercise, infection, pregnancy and medications. So you might need to repeat some tests.

If you have von Willebrand disease, your doctor might suggest that family members undergo tests to determine if this condition runs in your family.