Laboratory Diagnosis of von Willebrand Disease

Von Willebrand disease (VWD) is considered the most common congenital bleeding abnormality in the world and an accurate diagnosis is often very challenging. Clinical laboratories usually provide screening assays along with more complex assays to aid clinicians with the diagnosis. These assays measure different properties and activities of von Willebrand factor. They may be adversely affected by numerous preanalytical variables and often have variable performance characteristics that may contribute to an inadequate interpretation. This review describes methods used in the laboratory for diagnosing VWD and basic mechanisms of each of these assays. A thorough understanding of the assays and associated preanalytical variables in VWD testing is essential for accurate diagnosis. ABBREVIATIONS: ADAMTS13 - a disintegrin and metalloproteinase with a thrombospondin type 1 motif, DDAVP - 1-desamino-8-D-arginine vasopressin, EC - endothelial cell, VWD - von Willebrand disease, VWF - von Willebrand factor, VWF:Ag - von Willebrand factor antigen, VWF:CBA - von Willebrand factor collagen binding assay, VWF:RCo - von Willebrand factor ristocetin cofactor activity