Pathological Properties of Fibrin Thrombi in DIC

Abstract

It is essentially important and decisive to find fibrin thrombi in order to diagnose finally as DIC. However, fibrin thrombi is not necessary found so frequently in the cases of DIC clinically diagnosed. Therefore, the authors intended to clarify, 1) the mechanism of lysis or disappearance of thrombi in DIC, 2) to distinguish thrombus in general from that of DIC from morphological and staining points of view.Fibrin thrombi were in general classified into 2 types of pattern…an uniform pattern (I) and a fibrous pattern (II). Futhermore, (I) was subclassified into coating, bordering, spotty, and massed types. Generally (I) was found in capillary in cases of the acute DIC. Fibrin thrombi easily disappeared in the plasmin-treated paraffin preparations. In the electron microscopical findings, fibrin in (I) was significantly differed from the previously reported ones, and it was composed of the filamentous fibre with irregular arrangements, low densities, and showed homogeneous apperances. (I) was considered to be a soluble fibrin monomer complex or its resembled substances, but not a polymerized fibrin.(II) was classified into tangled, reticular, and waste thread types, and found frequently in capillary and small sized vessels, mostly in cases of the chronic DIC. Fibrin found in (II) was only slightly affected by the plasmin treatment. Therefore, it seemed to be affected by the action of stabilizing factor. The frequencies of fibrin thrombi found in DIC was generally quite differed from other authors' ones which are now available.In conclusion, the authors assumed that these results was occurred from remarkable differences in their fibrinolytic activities and to immediate fibrinolysis after postmortem.