VON WILLEBRAND FACTOR (O.S.)

Overview

Diagnosis of von Willebrand disease (VWD) and differentiation of VWD subtype (in conjunction with von Willebrand factor ristocetin cofactor activity and factor VIII coagulant activity)Differentiation of VWD from hemophilia A (in conjunction with factor VIII coagulant assay) VWF is an acute-phase reactant and may be elevated above baseline in association with a variety of conditions including inflammation, stress, exercise, liver disease, pregnancy or estrogen therapy. Baseline VWF levels also increase with aging. These conditions may obscure diagnosis of the milder forms of von Willebrand disease (VWD). 6 mL Whole blood in 2 Blue Top (Sodium Citrate) tubes. Mix thoroughly by inversion. Transport to Lab within 4 hours. If this is not possible, make PPP within 1 hour of collection as follows: Centrifuge sample at 3600 rpm for 15 min. & transfer supernatant to a clean plastic tube. Centrifuge this supernatant again at 3600 rpm for 15 min. & finally transfer the supernatant (PPP) to 1 labelled clean plastic screw capped vial. FREEZE IMMEDIATELY. Ship frozen. DO NOT THAW.