Loading...
Patients with von Willebrand disease (VWD) have repeated nose bleeding, menorrhagia, and excessive blood loss with surgery or trauma. Diagnostic tests include assays of von Willebrand factor (VWF). If the test values fall below the normal range, VWD is usually suspected and the diagnosis confirmed by genomic analysis. However, it is possible that not all VWF mutations are pathogenic; some might be innocent sequence variations. For example, the D1472H mutation affects the ristocetin binding site on VWF, resulting in decreased ristocetin cofactor activity. But do persons with this mutation have excessive bleeding?
To answer this question, investigators evaluated 277 patients with a pre-existing diagnosis of VWD; all had VWF antigen <60 IU/dL. …