Factor IX Activity, Clotting
Also known as: Christmas Factor, Antihemophilic Factor B, Factor IX Functional
Use
This test measures the activity of coagulation Factor IX using a photometric clot detection assay. It is intended for evaluation of Factor IX deficiency (hemophilia B) and for investigation of prolonged activated partial thromboplastin time (aPTT) in patients. The measured activity helps diagnose inherited or acquired Factor IX deficiencies.
Special Instructions
Not provided.
Limitations
Specimens must be free of hemolysis or thawing on receipt; frozen specimens are acceptable up to 14 days, while room temperature and refrigerated specimens are unacceptable. The assay is susceptible to interference by Factor IX inhibitors (both alloantibodies from replacement therapy and autoantibodies), which may yield falsely low activity results.
Methodology
Other
Biomarkers
Result Turnaround Time
Not provided.
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
Not provided
Minimum Volume
Not provided
Container
Plastic screw-cap vial
Collection Instructions
3 mL platelet‑poor 3.2% sodium citrate‑anticoagulated plasma, separated, frozen immediately; centrifuge 15 minutes at 2500‑3500 rpm, transfer platelet‑poor plasma into plastic vial, freeze and ship on dry ice
Causes for Rejection
Received room temperature; received refrigerated; received thawed; hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | Unacceptable |
| Frozen | 14 days |