von Willebrand Factor Antigen
Also known as: VWF/AG
Use
von Willebrand Factor Antigen testing is crucial in the diagnostic process for von Willebrand Disease (VWD), a genetic disorder caused by missing or defective von Willebrand factor (VWF), a clotting protein. This test measures the amount of von Willebrand factor in the blood, providing essential information for the diagnosis and management of bleeding disorders. It is typically ordered together with von Willebrand Factor Activity (Ristocetin Cofactor) and Factor VIII, Activity as part of the initial workup for suspected VWD.
Special Instructions
Order this test in conjunction with von Willebrand Factor Activity (Ristocetin Cofactor) (0030250) and Factor VIII, Activity (0030095) as these tests collectively help provide a clearer clinical picture in suspected cases of von Willebrand Disease. Follow ARUP’s specimen handling guidelines for optimal results.
Limitations
This test may not be sufficient to diagnose von Willebrand Disease independently; it should be paired with other tests like Factor VIII, Activity and von Willebrand Factor Activity for a comprehensive assessment. Sampling must be handled according to specified guidelines to maintain the validity of results. Unacceptable conditions including serum, EDTA plasma, clotted or hemolyzed specimens, may lead to rejection and a need for recollection.
New York Approved
Methodology
Immunoassay (Microlatex Particle-Mediated Immunoassay)
Biomarkers
LOINC Codes
- 27816-8
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1.5 mL
Minimum Volume
1 mL
Container
Lt. blue (sodium citrate) tube
Collection Instructions
Collect in a Lt. blue (sodium citrate) tube. Transfer 1.5 mL platelet-poor plasma to an ARUP standard transport tube.
Storage Instructions
CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.
Causes for Rejection
Serum, EDTA plasma, clotted or hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 hours |
| Refrigerated | Unacceptable |
| Frozen | 3 months |