Coagulation Factor V Activity Assay, Plasma
Use
This test is useful for diagnosing congenital deficiencies, which are rare, of coagulation factor V. It is also employed in evaluating acquired deficiencies associated with liver disease, factor V inhibitors, myeloproliferative disorders, and intravascular coagulation and fibrinolysis. Additionally, it aids in the investigation of prolonged prothrombin time or activated partial thromboplastin time.
Special Instructions
Coagulation testing is highly complex, often needing multiple assays and correlation with clinical information. Consider ordering a Coagulation Consultation for comprehensive insights. If you have a priority specimen, mark the request form, provide a reason, and request a call-back.
Limitations
Factor V is highly susceptible to proteolytic inactivation, which could lead to spurious assay results. Factor V activity may be 10% to 20% less in freeze-thawed citrate plasma compared to fresh specimens. A more significant decrease in factor V activity may occur in some individuals. Therefore, while normal results are reliable, decreased factor V activity results should be correlated with clinical and other laboratory data. Repeat testing may be necessary for verification.
New York Approved
Methodology
Automated Analyzer (Coagulation)
Biomarkers
LOINC Codes
- 3193-0
- 3193-0
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.5 mL
Container
Light-blue top (3.2% sodium citrate)
Collection Instructions
1. Specimen must be collected prior to factor replacement therapy. 2. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing. 3. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again. 4. Aliquot plasma into a plastic vial, leaving 0.25 mL in the bottom of centrifuged vial. 5. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C or, ideally, -40 degrees C or below.
Patient Preparation
Patient must not be receiving coumadin (warfarin) or heparin therapy. If not possible for medical reasons, note on request.
Causes for Rejection
Gross hemolysis, gross lipemia, gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 14 days |