Part 1: von Willebrand Disease: Approach to Diagnosis and Management

Natalia Rydz, MD

Clinical Assistant Professor, Division of Hematology and Hematologic Malignancies, Foothills Medical Centre, Calgary AB, Canada

Question 1

A 30-year-old man presents with prolonged bleeding after a dental extraction. Mild hemophilia A is suspected based on a baseline factor VIII (FVIII) level of 9 IU/dL. Further testing reveals the following: genotyping is negative for a F8 mutation; a desmopressin (DDAVP) trial shows a brisk but short-lived FVIII response; von Willebrand factor antigen (VWF:Ag) level is 0.55 IU/dL and VWF ristocetin cofactor (VWF:RCo) is 0.50 IU/dL.

What is the next most useful test?

  •   VWF multimer analysis
  •   Low-dose ristocetin-induced platelet aggregation (RIPA)
  •   VWF:FVIII binding assay (VWF:FVIIIB)
  •   VWF:collagen binding assay (VWF:CB)
  •   Mixing studies

Updated 1/22/2014 • jdw | Copyright ©2014 Turner White Communications