ANTITHROMBIN DEFICIENCY, CONGENITAL: WHAT IS ANTITHROMBIN DEFICIENCY, CONGENITAL?
Definition: What is "Antithrombin deficiency, congenital"?
Antithrombin deficiency, congenital definition: Antithrombin is a small protein molecule, which is responsible for inactivating several enzymes of the coagulation system. It consists of 432 amino acids & contains 3 disulfide bonds as well as 4 possible "glycosylation" sites. The role of antithrombin in regulating normal blood coagulation is demonstrated by the relationship between acquired & inherited antithrombin deficiencies. This relationship is also seen in the increased risk of developing thrombotic disease. Antithrombin deficiency usually appears to patient with recurrent pulmonary embolism & venous thrombosis.
Acquired antithrombin deficiency is a disorder resulting from various disorders, including sepsis, liver dysfunction, premature birth, kidney disease & nephritic syndrome. It could also be the result of interventions like cardiopulmonary bypass & any major surgery. Inherited Antithrombin deficiency occurs due to low circulating levels of functionally & structurally normal antithrombin. When this happens, the activity of normal antithrombin is reduced up to 50%. This type of Antithrombin deficiency is classified as "type I Antithrombin deficiency". Inherited Antithrombin deficiency may also be classified as "type II Antithrombin deficiency" when a functionally & structurally abnormal antithrombin protein circulates the blood. When this happens, levels of antithrombin could be normal, but the activity produced is reduced to 50%. Both type I & type II congenital Antithrombin deficiency has been shown to be the result of any nonsense mutations, missense mutations or frameshift mutations in genes that encode antithrombin.