Factor XII, Activity
Also known as: F12
Use
This test is used to evaluate the cause of an isolated prolonged partial thromboplastin time (PTT) in a patient who is not currently bleeding. Factor XII activity is crucial for understanding coagulation pathways and is often assessed to determine underlying issues related to clotting disorders.
Special Instructions
Separate specimens must be submitted when multiple tests are ordered. Refer to hemostasis/thrombosis specimen handling guidelines available at aruplab.com.
Limitations
Factor XII activity in a sample cannot be accurately quantitated due to non-parallelism if there is a specific factor inhibitor directed against a clotting factor involved in the PTT reaction or due to contamination with anticoagulants such as heparin, or direct thrombin inhibitors. Non-specific inhibitors like lupus anticoagulant may also affect results. Proper interpretation requires correlation with clinical information and additional laboratory testing.
New York Approved
Methodology
Other
Biomarkers
LOINC Codes
- 3232-6
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
2 mL
Minimum Volume
1 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Collect the specimen in a Lt. blue (sodium citrate) tube. After collection, transfer 2 mL of platelet-poor plasma to the transport tube.
Storage Instructions
CRITICAL FROZEN
Causes for Rejection
Serum, EDTA plasma, clotted or hemolyzed specimens are unacceptable.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 hours |
| Refrigerated | Unacceptable |
| Frozen | 2 weeks |
Other tests from different labs that may be relevant