- Last Update On : 2013-02-02
The thrombin time is a measure of time it takes a standard thrombin solution to clot plasma. It is a test of the final step of the coagulation pathway, which involves the conversion of fibrinogen to fibrin. Prolongation of the thrombin time may be caused by decreased fibrinogen concentration (usually < 90 mg/dL) or production of abnormal fibrinogen molecules (dysfibrinogenemia), such as may be associated with liver disease. The thrombin time may also be prolonged by an inhibitor of the fibrinogen to fibrin step, such as high levels of fibrin degradation products, and heparin therapy. It may also be prolonged in cases of multiple myeloma and macroglobulinemia, due to interference of the paraprotein with fibrin polymerization.
Reference range is 14.0 to 17.6 seconds.
Specimen requirement is one light blue top (sodium citrate) tube of blood.