1st June 2023

Von Willebrand disease

In von Willebrand disease (VWD), the protein, von Willebrand factor, which is required for platelet adhesion is defective or diminished due to an autosomally inherited defect. VWD causes increased bleeding and can be divided into three types: type 1 (the mildest and commonest), 2 and 3 (the most severe and rarest).

Signs and symptoms

Some cases of VWD can be asymptomatic and are only diagnosed if a family member has the disease.  Signs and symptoms depend on the type of VWD. Usually, Type 1, 2A, 2B and 2M VWD present with mucocutaneous bleeding, such as easy bruising, epistaxis, and menorrhagia. Type 2N WVD can present similarly to mild haemophilia and type 3 WVD can present with severe bleeding as patients have almost no von Willebrand’s factor.

Diagnosis

Screening tests include:

• FBC – may be normal, but can show microcytic anaemia due to ongoing blood loss or thrombocytopenia in some types of VWD
• APTT – can be normal or prolonged (if factor VIII levels are reduced)
• PT – usually normal
• Bleeding time – prolonged

Diagnostic tests include:

• VWF antigen levels – to measure the amount of VWF
• VWF ristocetin cofactor activity – to measure how well the VWF is working
• VWF multimers – this can help to diagnose the type of VWD
• Factor VIII clotting activity – to measure how well VWF is binding to factor VIII

Management

• Desmopressin – works by stimulating the body to release more von Willebrand factor (it can be used for mild/moderate type 1 VWD and it can occasionally be useful in type 2 VWD)
• VWF/FVIII concentrates – can be used to treat bleeding in patients with severe bleeding in type 1 VWD or type 1 WVD which is unresponsive to desmopressin, type 2 and type 3 VWD
• Fibrinolysis inhibitors, such as tranexamic acid
•  COCP for menorrhagia
•  Local measures to stop bleeding