Acquired thrombin inhibitor in a patient with liver cirrhosis.
An unusual thrombin inhibitor is described in a patient suffering from liver cirrhosis, associated with a polyclonal gammopathy. In all screening tests that are based on thrombin action, the plasma clotting time was prolonged; in contrast, a test using the thrombin-like enzyme thrombin coagulase was not influenced. A specific thrombin inhibitor, present in the patient's plasma, was assumed. Fractionation experiments showed that the inhibitor was associated with the patient's IgG fraction. The IgG fraction dose-dependently inhibited the action of thrombin on fibrinogen and the inhibition of thrombin by antithrombin III, but the amidolytic activity of thrombin was only little affected.
D000368:Aged; D000917:Antibody Formation; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D008103:Liver Cirrhosis / Q000276:immunology* / Q000503:physiopathology; D013917:Thrombin / Q000037:antagonists & inhibitors*; D013918:Thrombin Time
D007074:Immunoglobulin G; D013917:Thrombin