Test Directory
Antithrombin III Activity
Justification
Antithrombin III (ATIII) is a glycoprotein inhibitor of thrombin and factor Xa, whose activity is greatly potentiated by heparin. ATIII deficiencies are associated with a high risk of venous thromboembolic disease. Approximately 55 percent of patients with AT deficiency who have a family history of venous thromboembolism experience venous thrombotic episodes by the age of 50.
STAT: < 24 hours (7 days a week)
Chromogenic
Draw Tube: Blue Top
Sample Type: Citrated Plasma
Specimen Requirements
| Sample Type | Volume Required | Minimum Volume | Stability | |
|---|---|---|---|---|
| PREFERRED | Citrated Plasma | 1mL | 0.5mL | Frozen (-20C): 2 weeks Frozen (-80C): 6 months |
| ALTERNATIVE | - | - | - | - |
| REJECTION CRITERIA | Thawed in transit, refrozen or clotted sample |
| SPECIAL INSTRUCTIONS | - |
General Information
| METHODOLOGY | Chromogenic |
| 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 | ATIII Activity, AT3 Activity |
| DESCRIPTION | Chromogenic assay for the quantitative determination of ATIII activity in human plasma. |
| LIMITATIONS | - |
| NORMAL RANGE | 86-122% |
| ASSOCIATED TESTING | - |
| REFERENCES | Mackie M, Bennett B, Ogston D, Douglas AS. Familial thrombosis: inherited deficiency of antithrombin III. Br Med J 1978; 1:136. |
| SAMPLE REPORT | Upon request |
| NEW YORK STATE APPROVED | No |
Test Codes
| ORDER CODE | P3036 |
| CPT CODE | 85300 |
| LOINC CODE | 27811-9 |