Test Directory
Factor XII (12) Inhibitor Titer
Justification
Acquired factor deficiencies may occur due to the development of factor-specific inhibitory antibodies. These antibodies may also develop against factor replacement products in patients with a congenital deficiency. This test may be used to detect and quantitate inhibitory antibodies against Factor XII.
STAT: < 24 hours (7 days a week)
Bethesda, Clot-based
Draw Tube: Blue Top
Sample Type: Citrated Plasma
Specimen Requirements
| Sample Type | Volume Required | Minimum Volume | Stability | |
|---|---|---|---|---|
| PREFERRED | Citrated Plasma | Two aliquots, 1mL each | Two aliquots, 0.5mL each | Frozen (-20C): 2 weeks Frozen (-80C): 6 months |
| ALTERNATIVE | - | - | - | - |
| REJECTION CRITERIA | Thawed in transit, refrozen or clotted sample |
| SPECIAL INSTRUCTIONS | - |
General Information
| METHODOLOGY | Bethesda, Clot-based |
| STAT TAT | < 24 hours (7 days a week) |
| STAT TAT Performance | > 90% of results released in 24 hours 7 days a week |
| ROUTINE TAT | < 3 days (M-F) |
| ALTERNATIVE NAMES | Hageman Factor inhibitor, F12 inhibitor, FXII inhibitor |
| DESCRIPTION | Bethesda titer for the quantitative determination of a specific factor inhibitor against factor XII (12). |
| LIMITATIONS | - |
| NORMAL RANGE | < 0.4 BU |
| ASSOCIATED TESTING | - |
| REFERENCES | - |
| SAMPLE REPORT | Upon request |
| NEW YORK STATE APPROVED | No |
Test Codes
| ORDER CODE | P3417 |
| CPT CODE | 85280, 85335 |
| LOINC CODE | 3232-6 |