Coagulation Factor X Activity Assay, Plasma
Use
The Coagulation Factor X Activity Assay is useful for diagnosing deficiencies in coagulation factor X, which can be congenital or acquired. It helps evaluate hemostatic function in liver disease and investigate prolonged prothrombin time or activated partial thromboplastin time. Factor X, a vitamin K-dependent serine protease synthesized in the liver, plays a crucial role in both intrinsic and extrinsic coagulation pathways as part of the prothrombinase complex. Deficiency in factor X can lead to prolonged bleeding times, making this assay crucial for proper diagnosis.
Special Instructions
For priority specimens, it is necessary to mark the request form, provide the reason, and request a call-back. Double centrifugation of specimens is critical to avoid platelet contamination, which may cause spurious results. Each coagulation assay requested should have its own vial. Coagulation testing often requires multiple assays correlated with clinical information, hence a Coagulation Consultation is recommended.
Limitations
This assay has not been cleared or approved by the US Food and Drug Administration. It has been modified from the manufacturer's instructions, and its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. Gross hemolysis, lipemia, or icterus can lead to specimen rejection. Improper specimen collection and handling may cause diagnostic confusion.
New York Approved
Methodology
Automated Analyzer (Coagulation)
Biomarkers
LOINC Codes
- 3218-5
- 3218-5
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.5 mL
Container
Plastic vial
Collection Instructions
For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing. Within 4 hours of collection, centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again. Aliquot plasma into a separate plastic vial leaving 0.25 mL in the bottom of the centrifuged vial. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C, or ideally at or below -40 degrees C.
Causes for Rejection
Gross hemolysis, gross lipemia, gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 14 days |