MEASURING PLASMA-FIBRINOGEN LEVELS IN PATIENTS WITH LIVER-CIRRHOSIS -THE OCCURRENCE OF PROTEOLYTIC FIBRIN(OGEN) DEGRADATION PRODUCTS AND THEIR INFLUENCE ON SEVERAL FIBRINOGEN ASSAYS

In patients with liver cirrhosis the fibrinogen molecule is under cons tant attack of various proteolytic enzymes, which might affect results of the different assay systems for fibrinogen. We therefore studied t he measurement of fibrinogen in the plasma of patients with mild, mode rate and severe cirrhosis of the liver. Fibrinogen levels were measure d with the Clauss method (functional fibrinogen); an enzyme immune ass ay (EIA) for HMW+LMW fibrinogen; and an assay that measures the total clottable fibrinogen. With all three methods we found normal or slight ly increased fibrinogen levels in patients with mild or moderate cirrh osis, whereas patients with severe cirrhosis had decreased levels. No evidence was found for increased partial fibrinogen proteolysis, resul ting in increases of LMW'-fibrinogen in cirrhotic patients. We further observed that fibrinogen degradation products levels increased slight ly with the severity of the disease, but were still in the normal rang e in patients with severe cirrhosis. This indicates a very low level o f primary fibrinolysis. Fibrin degradation products levels increased m uch stronger, which points to intravascular coagulation. The levels of the fibrin degradation products remained below the level where they a re expected to influence the Clauss assay. In patients with liver cirr hosis the measurement of plasma fibrinogen levels with the three studi ed methods give comparable results. We suggest to apply the Clauss ass ay in cirrhotic patients because of this and because it has a good rep roducibility and because the test is cheap, quick and easy to perform.