Contact Factor Evaluation Profile (Esoterix)
Use
The Contact Factor Evaluation Profile test is used to evaluate the functionality of certain proteins involved in the coagulation cascade. Specifically, it measures the activity levels of Factor XI, Factor XII, high molecular weight kininogen (Fitzgerald factor), and prekallikrein (Fletcher factor), which are part of the intrinsic pathway of blood coagulation. This test helps diagnose clotting disorders and guides the management of patients with suspected bleeding disorders.
Special Instructions
Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio. The sample should be mixed immediately by gentle inversion to ensure adequate mixing. A discard tube is not required except when using a butterfly device. When noncitrate tubes are collected for other tests, collect sterile and nonadditive tubes before citrate tubes. Centrifuge and carefully transfer the plasma without disturbing the cells. Freeze immediately.
Limitations
The test's performance characteristics have been determined by LabCorp but have not been cleared or approved by the FDA. Results labeled for research purposes only by the assay's manufacturer should not be used for treatment or diagnostic purposes without confirmation by another method. Severely hemolyzed samples, improperly labeled specimens, clotted specimens, diluted samples, thawed samples, improper sample type, or samples out of stability may be rejected.
Methodology
Other
Biomarkers
LOINC Codes
- 3226-8
- 3232-6
- 52754-9
- 52759-8
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
4 mL (2 mL in each of two tubes)
Minimum Volume
Not provided
Container
Blue-top (sodium citrate) tube
Collection Instructions
Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio. A discard tube is not required except when using a butterfly device. Carefully transfer the plasma without disturbing the cells. Freeze immediately.
Patient Preparation
Do not draw from an arm with a heparin lock or heparinized catheter.
Storage Instructions
Freeze.
Causes for Rejection
Severe hemolysis; improper labeling; clotted specimen; specimen diluted with IV fluids; samples thawed in transit; improper sample type; sample out of stability.