Von
Willebrand assay
Specimen requirements:
Fresh whole blood collected in
sodium citrate at a 9:1 ratio of blood to anticoagulant
Function:
Acts in primary hemostasis by acting
as a receptor for platelet adhesion to collagen
The level of von Willebrand protein
can be measured using:
Tested within 8 hours or stored at
-20oC for 1 month
Testing methods:
ELISA
Electroimmunoassay
(EIA)
Radioimmunoassay (RIA)
Abnormal levels result in prolonged
bleeding time
Clinical application: