Use

Antithrombin III Antigen measurement aids in characterization of antithrombin deficiency, which is associated with increased thrombotic risk. Type I deficiency shows reduced activity and antigen levels, while Type II shows relatively lower activity versus antigen levels. Acquired deficiency (e.g., from liver disease, nephrotic syndrome, heparin therapy, DIC, sepsis, L‑asparaginase chemotherapy) is more common than inherited forms.