von Willebrand factor (vWf).activity [Units/volume] in Platelet poor plasma by Immunoassay

vWf:Ac PPP IA-aCnc

Definition

Von Willebrand Factor Activity (VWF Activity, vWF:Act) in plasma specimens can be quantitatively determined by immunological methods. This code is created for, but not limited in use to, the submitter's kit, HemosIL Von Willebrand Factor Activity Kit, which determines VWF activity by measuring the increase of turbidity produced by the agglutination of the latex reagent. This assay uses a specific anti-VWF monoclonal antibody directed against the platelet binding site of VWF, glycoprotein Ib receptor, and reacts with the VWF in patient plasma. The degree of agglutination is directly proportional to the activity of VWF in the sample and is determined by measuring the decrease of transmitted light caused by the aggregates. The submitter's lab reports the results in U/mL where U represents "units" rather than the standard meaning of U, which is mmol/Min, a measure of enzyme rates. Additional testing (e.g. ristocetin cofactor assay) may be needed to confirm a diagnosis of von Willebrand disease (VWD).

Activ; Actvty; Arbitrary concentration; COAGULATION; EIA; ELFA; ELISA; Enzyme immunoassay; Fac; Fact; Hematology; Heme; IAA; MEIA; Movements; Plas; Platelet poor plasma; Point in time; QNT; Quan; Quant; Quantitative; Random; SUDS; Von will; Vonwillebrand; vWf; vWf:Ac