Detection of intravascular coagulation.

A method is described for the measurement of soluble thrombin-altered fibrinogen (circulating fibrin) in human plasma. This method is dependent upon the enzymatic incorporation of glycine ethyl ester-(14)C (GEE-(14)C) into circulating fibrin by the action of the fibrin-stabilizing enzyme, factor XIII. The mean incorporation of GEE-(14)C into the fibrinogen of normal human plasma controls was 167 +/-47 dpm/mg fibrinogen. The addition of 0.03 NIH U/ml of thrombin to normal human plasma resulted in a two to threefold increase in the incorporation of GEE-(14)C into the fibrinogen. The addition of plasmin split products of fibrinogen to normal plasma did not increase the incorporation of GEE-(14)C unless these products were also exposed to thrombin. The addition of plasmin split products of a fibrin clot resulted in only minimal increase in the incorporation of GEE-(14)C (57 dpm/mg fibrinogen) at 37.5% concentration. The method was therefore sensitive to thrombin alterations of fibrinogen but insensitive to plasmin alterations of fibrinogen and fibrin.Clinically, the method was found to provide useful information for the diagnosis and treatment of disseminated intravascular coagulation in two patients with meningococcemia, two patients with Rocky Mountain spotted fever, and three patients in whom therapeutic abortions were induced by the injection of hypertonic saline.