[Laboratory identification of blood hypercoagulability].

For many years, the laboratory investigation of patients with thrombophilia has lagged behind that of patients with bleeding diathesis. The improved understanding of the mechanisms that control and regulate coagulation, and resultant recognition of new defects have greatly stimulated clinical laboratory interest in this area. Assays regarding the developed resistance to activated protein C, deficiencies of antithrombin, protein C and protein S, and the presence of antiphospholipid antibodies are widely available and should be a part of investigations of patients with idiopathic thrombosis. Such a study would likely provide an explanation of thrombosis in 40-60% of patients. Abnormalities of fibrinogen and fibrinolysis may be explained, although such defects are currently considered rare. More sophistic assays are being developed to detect abnormalities de to factor V Leiden and prothrombin 20,210 gene mutation, which will undoubtedly detect more patients with thrombophilia. Laboratory tests to define the hypercoagulable state are continually being developed. They include tests for novel activation markers. However, acceptance of these approaches by clinical laboratories has been slow.