Lab Code : VWD
Test Background Von Willebrand disease (vWD) is the commonest inherited bleeding disorder, affecting up to 1 % of individuals, irrespective of gender or ethnicity. It comprises a number of types, all of which are characterised by a bleeding defect that resembles a platelet function defect, as platelet adhesion is impaired. The von Willebrand factor (vWF) also serves as a carrier protein for factor VIII and levels of factor VIII are often decreased when vWF levels are decreased. vWD is usually inherited as an autosomal dominant condition.
Clinical Indications Bleeding diathesis/hypocoagulopathy with presentations of epistaxis, menorrhagia and GI haemorrhaging Differential diagnosis of haemophilia and other forms of bleeding diathesis
Reference Range See Factor Assays for the Factor VIII reference ranges and Collagen Binding assay for appropriate range also
Sample Required 3 x 2.7 mL sodium citrate (pale blue top) adults3 x 1.8 mL sodium citrate (pale blue top) paediatrics
Turnaround Time 14 days
Notes Special handling: avoid prolonged stasis during venepuncture. Sample must be received by lab within 4 hours of collection. Please note: samples will be rejected if underfilled or overfilled.