Factor IX Activity with Reflex to Bethesda Quantitative, Factor IX
Also known as: F9 BETHR
Use
This test is used primarily to diagnose factor IX deficiency, also known as hemophilia B, by measuring the activity of factor IX in the blood. It also detects the presence of factor IX inhibitors, which can interfere with the coagulation process, thus helping in monitoring factor IX replacement therapy in patients with hemophilia B.
Special Instructions
Platelet-poor plasma samples should be collected in sodium citrate tubes. The plasma must be transported as two 3 mL aliquots in separate ARUP Standard Transport Tubes, and it is critical to keep them frozen for accurate testing.
Limitations
Factor IX activity measurement may be influenced by non-parallelism resulting from specific factor inhibitors, certain anticoagulant therapies such as heparin, or contamination during sample collection. Interpret results in conjunction with clinical information and additional laboratory tests.
New York Approved
Methodology
Other
Biomarkers
LOINC Codes
- 3185-6
- 3187-2
- 3185-6
- 3187-2
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
Two 3 mL aliquots
Minimum Volume
2 mL each
Container
ARUP Standard Transport Tubes
Collection Instructions
Collect in lt. blue (sodium citrate) tubes. Follow hemostasis/thrombosis specimen handling guidelines.
Storage Instructions
CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.
Causes for Rejection
Serum, EDTA plasma, clotted or hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 hours |
| Refrigerated | Unacceptable |
| Frozen | 2 weeks |