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von Willebrand Factor

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Also known as: VWF:Ag; VWF:RCo; von Willebrand Panel; Ristocetin Cofactor
Formal name: von Willebrand Factor Antigen and von Willebrand Factor Activity

At a Glance

Why Get Tested?

To help determine the cause of unexplained excessive or repeated episodes of bleeding, to diagnose von Willebrand disease (VWD), and to distinguish between different types of VWD

When to Get Tested?

When you have a personal or family history of heavy, prolonged, and/or spontaneous bleeding; when your health care provider suspects that you may have a bleeding disorder

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?