Testing for soluble fibrin complexes was performed using a sensitive and reliable haemagglutination assay, with red cells sensitized by fibrin monomers. The principle is based on the fact that the monomers linked to red cells and induce their agglutination. This test, used in clinical trials, has revealed the presence of soluble complexes in every confirmed case of acute DIC, but also in Chronic DIC where diagnosis is difficult to establish (negative ethanol gelation test, normal or sub-normal levels of fibrin breakdown products). In Cirrhosis of the liver, the test gives positive results in a non negligible number of cases. Several hypotheses are made to explain why in certain confirmed cases of DIC, low fibrin breakdown products levels are found.