Antithrombin III is a protein that helps regulate blood clotting by inhibiting thrombin and other clotting factors. This test measures the activity level of antithrombin in your blood.
Category: Coagulation
Also known as: antithrombin iii, antithrombin 3, at iii, at3, antithrombin, antithrombin activity
Reference range: 80–120 % (Source: ABIM)
Standard unit: %
High values may indicate
High antithrombin III levels are uncommon and generally not clinically significant, though they may be seen with acute hepatitis or vitamin K deficiency.
Low values may indicate
Low antithrombin III levels may indicate an increased risk of blood clots (thrombosis), liver disease, disseminated intravascular coagulation (DIC), or a hereditary antithrombin deficiency.