Test Code ATTI Antithrombin Antigen, Plasma
Reporting Name
Antithrombin Antigen, PUseful For
Assessing abnormal results of the antithrombin activity assay (ATTF / Antithrombin Activity, Plasma), the recommended primary (screening) antithrombin assay
Diagnosing antithrombin deficiency, acquired or congenital, in conjunction with measurement of antithrombin activity
An adjunct in the diagnosis and management of carbohydrate-deficient glycoprotein syndromes
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
Plasma Na CitOrdering Guidance
For monitoring treatment of antithrombin deficiency disorders, including infusion of antithrombin therapeutic concentrate, order ATTF / Antithrombin Activity, Plasma.
Necessary Information
If patient is being treated with heparin, this should be noted as heparin treatment may lower plasma antithrombin.
Specimen Required
Specimen Type: Platelet-poor plasma
Patient Preparation: Fasting preferred
Collection Container/Tube: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Polypropylene vial
Specimen Volume: 1 mL
Collection Instructions:
1. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing.
2. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again.
3. Aliquot plasma into a plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
4. Freeze plasma immediately (no longer than 4 hours after collection) at -20° C or, ideally, at-40° C or below.
Additional Information:
1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Each coagulation assay requested should have its own vial.
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Na Cit | Frozen | 14 days |
Special Instructions
Reference Values
Adults: 80-120%
Normal, full-term newborn infants may have decreased levels (≥35-40%) that reach adult levels by 180 days postnatal.*
Healthy, premature infants (30-36 weeks gestation) may have decreased levels that reach adult levels by 180 days postnatal.*
*See Pediatric Hemostasis References section in Coagulation Guidelines for Specimen Handling and Processing.
Day(s) Performed
Monday through Friday
Test Classification
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
85301
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
ATTI | Antithrombin Antigen, P | 27812-7 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
ATTI | Antithrombin Antigen, P | 27812-7 |
Interpretation
Hereditary antithrombin deficiency is much less common than acquired deficiency. Diagnosis of hereditary deficiency requires clinical correlation, testing of both antithrombin activity and antithrombin antigen, and may be aided by repeated testing and by family studies. DNA-based diagnostic testing may be helpful but is generally not readily available.
Acquired antithrombin deficiency may occur in association with a number of conditions (see Clinical Information). The clinical significance (thrombotic risk) of acquired antithrombin deficiency is not well established, but accumulating information suggests possible benefit of antithrombin replacement therapy in carefully selected situations.(4)
Increased antithrombin activity has no definite clinical significance.
Clinical Reference
1. Bock SC. Antithrombin III and heparin cofactor II. In: Colman RW, Hirsh J, Marder VJ, et al, eds. Hemostasis and Thrombosis. 4th ed. Lippencott Williams and Wilkins; 2001:321-333
2. Viazzer H. Hereditary and acquired antithrombin deficiency. Semin Thromb Hemost. 1999;25(3):257-263
3. Conrad J. Antithrombin activity and antigen. In: Laboratory Techniques in Thrombosis-A Manual. 2nd ed. Kluwer Academic Publishers; 1999:121-128
4. Lane DA, Bayston T, Olds RJ, et al. Antithrombin mutation database: 2nd (1997) update. For the Plasma Coagulation Inhibitors Subcommittee of the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis. Thromb Haemost. 1997;77(1):197-211
5. Van Cott EM, Orlando C, Moore GW, et al. Recommendations for clinical laboratory testing for antithrombin deficiency; Communication from the SSC of the ISTH. J Thromb Haemost. 2020;18(1):17-22
Report Available
Same day/1 to 4 daysMethod Name
Latex Immunoassay (LIA)
Forms
If not ordering electronically, complete, print, and send a Coagulation Test Request (T753) with the specimen.