Coagulation
Coagulation laboratory tests
von Willebrand disease testing - general

Author: Jeremy Parsons, M.D. (see Authors page)

Revised: 18 May 2016, last major update November 2012

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed Search: von Willebrand disease testing

Cite this page: von Willebrand disease testing - general. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/coagulationvWFtestinggeneral.html. Accessed December 3rd, 2016.
Definition / General
  • Often need to repeat tests because von Willebrand factor and factor VIII are elevated during acute phase reactions, pregnancy, estrogen use and in newborns - can measure fibrinogen (acute phase reactant) to determine if acute phase condition exists

  • Tests: von Willebrand factor antigen assay, von Willebrand factor activity (ristocetin cofactor activity), factor VIII levels, fibrinogen (or other acute phase reaction marker) or multimer analysis
Interpretation
  • All results normal (considering ABO blood type) - unlikely to have vWD if no acute phase reaction, pregnancy, estrogen use or newborn (Thromb Haemost 1994;71:520)
  • All results normal but elevated fibrinogen / factor VIII - acute phase reaction may mask abnormalities; repeat when fibrinogen and factor VIII levels are normal
  • Reduced antigen, activity and factor VIII - likely type 1 vWD
  • Severely reduced (< 10%) or undetectable antigen, activity and factor VIII - likely type 3 vWD

  • Activity reduced more than antigen and factor VIII - possibly type 2 vWD; perform multimer analysis and low dose ristocetin cofactor
    • Normal multimer analysis - likely type 2M vWD
    • Missing high molecular weight multimers - likely type 2A vWD
    • Missing high and intermediate molecular weight multimers - likely type 2B or platelet type vWD
    • Increased low dose ristocetin aggregation - likely type 2B or platelet type vWD
    • Normal or decreased low dose ristocetin aggregation - not type 2B or platelet type vWD
    • Reduced factor VIII (5 - 40%), normal activity and activity - possibly type 2N vWD or in males, mild hemophilia A; also possibly factor VIII degradation due to processing delay