Antithrombin III Antigen Blood Test

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Feature	Labcorp	Quest Diagnostics
Price	Coming soon	$26.99
Results in	—	~5 business days
Sample type	—	Blood Plasma
Require fasting	—	No

About the test

Aids in characterization of Antithrombin deficiency (AT, previously referred to as Antithrombin III) which is associated with increased thrombotic risk. Type I deficiency is characterized by reduction in activity and antigen levels simultaneously. With type II deficiency, activity levels are lower in comparison to the antigen levels (dysfunctional protein). Acquired deficiency, more common than inherited defects, can occur due to: liver disease, nephrotic syndrome, heparin therapy, disseminated intravascular coagulation (DIC), sepsis, and L-asparaginase chemotherapy.

Note: Target-specific anticoagulant therapy (anti-Xa medications, direct thrombin inhibitors) may cause false positive results for Lupus anticoagulant testing but do not impact the Cardiolipin, B2GPI and Phosphatidylserine-Prothrombin antibody testing.

Included biomarkers & Reference ranges

Biomarker	Reference range
Antithrombin III Antigen Measures the amount of antithrombin, a natural anticlotting protein, in your blood, used when looking for causes of an increased tendency to clot.	—

Reference ranges vary by lab, age, and sex (M/F). Your report shows your exact range. Click any biomarker to see its optimal range and what your results mean.

How it works

1. Order online No referral or insurance
2. Get a requisition By email in 24–72 hours
3. Visit a draw center Bring a matching photo ID
4. Get results Securely by email

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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