Laboratory Services
Von Willebrand Factor Activity
Print this pageUpdated Test Information:
| Test Description |
Von Willebrand Factor Activity
|
|
|---|---|---|
| Synonym(s) |
Ristocetin Cofactor Alternative, VWF Activity, UOW843 |
|
| Test ID |
VWFACT
|
|
| General Information |
VWF activity is measured using latex particles coated with purified anti-vWF mouse monoclonal antibody directed against the platelet binding site of VWF (the glycoprotein Ib receptor). This assay is used instead of the ristocetin cofactor assay due to better assay performance. Clinical assay interference and limitations: The presence of rheumatoid factor may produce an overestimation of the vWF level. The presence of HAMA (human anti-mouse antibody) may lead to an over-estimation of vWF level using this assay. |
|
| Container Type |
3 or 5 mL BLUE TOP (CITRATE) tube |
|
| Specimen Type |
Plasma |
|
| Specimen Requirements |
Sample must be centrifuged, aliquoted and frozen within 4 hours of collection |
|
| Specimen Collection / Processing Instructions |
Centrifuge for 10 minutes, remove plasma & re-spin plasma for another 10 minutes. Decant & Freeze plasma (minimum 1.0 mL) @ -20°C to -80°C. Send frozen on dry ice. |
|
| Stability |
Frozen |
|
| Department (code) |
Coagulation |
|
| Methodology |
Latex Immunoassay (LIA) |
|
| Testing Schedule |
Tuesday |
|
| CPT Code(s) |
85245 |
|
| Reference Range |
Units: % Male/Female 50-200 Effective date: 10/03/2006 |
|
| Performing Lab |
UW |
|
| LOINC Code(s) |
