von Willebrand Factor Antigen VWFAC
|Method(s)||Microlatex-Particle Mediated Immunoassay (LIA)|
One adequately filled 3.0 mL light blue (sodium citrate) top tube.
**TIME SENSITIVE** For specimens that cannot be shipped to the laboratory to arrive within 4 hours of collection, see Collection and Processing of Coagulation Specimens information (link below).
Draw blood into citrate (light blue) top tube filled to the proper level (1 part anticoagulant to 9 parts blood). Invert tube 3-4 times to avoid clotting.
|Stability||Ambient or Refrigerated: 4 hours; Frozen platelet-poor plasma: 2 weeks.|
Specimens that are clotted, hemolyzed, collected in the wrong tube, less than 90% filled, exceed stability limits or non-frozen plasma are unacceptable for testing.
|Notes||Anticoagulent therapy may interfere with test results.|
|Preferred Specimen Collection Device(s)|