von Willebrand Disease

A hereditary or acquired coagulation disorder resulting from either a qualitative change of vWF (usually a mutation giving rise to an abnormal vWF) or quantitative deficiency of vWF. There are three types of hereditary vWF deficiencies: Type 1, Type 2, and Type 3. Type 1 is the most common form and is a quantitative defect where vWF are decreased. Most patients are asymptomatic; however, symtoms such as prolonged bleeding post-surgery, menorrhagia, or easy bruising can occur. Type 2 is subdivided into 2A, 2B, 2M, and 2N, and it is a qualitative defect of vWF. Type 2B is unique in that the mutation leads to an increased binding of platelets to vWF and increased clearance thus producing a mild thrombocytopenia. Type 2M and 2N are rare. Type 3 is the most severe form and has no detectable levels of vWF.