von Willebrand Factor Antigen

Test Code
VWAG


Alias/See Also
VWF Antigen


CPT Codes
85246

Preferred Specimen
One 4.5ml blue top. Minimum volume 2.7 mL.


Instructions
Collect one full sodium citrate tube (blue top).  Send to lab immediately.  If the specimen needs to be transported, centrifuge the specimen, aliquot the specimen into a separate container, spin again, aliquot the specimen into a new container and freeze.


Transport Container
Sodium citrate (blue top)


Transport Temperature
Frozen


Specimen Stability
Specimen must be centrifuged within one hour of collection. 

Room Temperature: 4 hours (centrifuged)
Refrigerated: Not acceptable
Frozen: 30 days


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Specimens which are not properly filled do not contain the proper anti-coagulant to blood ratio and are therefore rejected.  Hemolyzed and clotted specimens are also unacceptable for testing.



Methodology
Turbidimetric

Setup Schedule
Set up daily


Report Available
Turn around time: Reports in 24 hours.




The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.