British Journal qf Haematology, 1975, 30, 95.

Fibrinogen Metabolism in Acute Hepatitis and Active Chronic Hepatitis R. D. CLARK, B. G. GAZZARD, M. L. LEWIS,1’. T. FLUTE” AND ROGER WILLIAMS

(Received 28 Az4g~rsf1974; acccytcd-for ytrblicatiori 14Octobcr 1974)

SUMMARY.Coagulation studics, including those of radioactivc fibrinogen iiietabolism, were performed in seven paticiits with acute viral liepatitis and 12 patients with active chronic hepatitis. An increased fractional catabolic rate for fibrinogcn was observed in four paticiits from tlic first group, and seven froiii tlie sccond. The catabolic rate was increascd in thosc patients with the grcatest dcgrec of hepatic necrosis as demonstrated by thc raised scruin aniinotraiisferasc levels. Thcrc was 110 corrclatioii bctwcen the ratc of fibrinogen catabolism and tlie standard clotting tcsts, but the SDPS test (indicating tlie presence of fibrin inoiioniers in the circulation) was consistently positive in thosc cases whcrc the catabolic rate was incrcascd. Coagulation abiiornialitics in liver disease arc usually attributed solely to an inipaircd capacity

of the liver to syiithesizc clotting factors (Sherlock, 1963). Howcver, rcceiit findings in fulrninant hepatic failure, wherc thcre is massive necrosis of tlic liver, liavc suggested that iiitravascular coagulatioii also occurs aiid may coiitributc to the coagulatioii disturbance by dcpletioii of some of the clotting factors (Rake ct a / , 1970). This extra mechanism may bc a feature of other varictics of livcr disease whcre necrosis of livcr cells is a promincnt fcaturc of the hepatic lesion. hi this paper we report findings in paticiits with acute viral hepatitis and active chronic hepatitis in whom, in addition to the standard coagulatioii tcsts measured, the catabolic rate of labelled fibriiiogcii has also bccii dcterinincd.

METHODS Standard incthods were used for the platelet count, onc-stage prothrombin time with human brain thromboplastiii, partial thromboplastin time with kaolin, and thrombin clotting time (Hardisty & Ingram, 1965). The results werc all expressed as a ratio with a normal control. Fibrinogen was estimated gravimetrically (higram, 1961). Serum FR-antigen was measured by the human tamed red cell liaemaggluti~iatio~i inhibition technique (Merskcy et al, 1969) aiid circulating plasmiiiogeii activator was measured on bovine fibrin plates (Astrup &

* Present

address: Department of Haematology, St George’s Hospital Mcdical School, London SW17 oQT.

Correspondence: Dr R. Williams, Liver Unit, King’s College Hospital, Denmark Hill, London, S.E.5.



R. D. Clark! et a1

Mullertz, 1952). The presence of fibrin strands in the plasma after protamine precipitation was assessed by the serial dilution of protamine sulphate (SDPS) test (Gurewich & Hutchinson, 1971). Radioactive Fibrinogen Studies Daily measurements of body weight, fibrinogen and PCV were performed in all patients to ensure the existence of a steady state. The variation in fibrinogen is given in Tables I1 and IV as the standard deviation calculated for daily measurements during the fibrinogen studies ; the PCV and body weight varied by less than 5 % and there was no clinical evidence of bleeding during the study. The turnover of ['251]fibrinogen was measured in these patients (Regoeczi, 1971). Human fibrinogen was obtained from accredited donors (Kabi Pharmaceuticals Ltd) and was iodinated by the method of McFarlanc (1963). The clottability was greater than 90% in all studies. Uptake of radioactivity by the thyroid gland was prevented by giving IOO mg potassium iodide before the injection of radioactive fibrinogen and thereafter daily. After intravenous injection of a measured dose of approximately 50 pCi, blood was collected at 15 min and then at timed intervals for 7 days into sodium edetate (Sequestrene). In some patients the plasma volume was calculated from the 15 min sample. Plasma was separated by centrifugation at 2000 g and counted in a Packard autogamma spectrometer (A). The I ml sample was then diluted to 9 ml with a phosphate buffer (18.2 g K H 2 P 0 4 , 9.4 g N a 2 P 0 4dissolved in I 1. distilled water, pH 6.4), to reduce adsorption of other proteins, and 50 u of bovine thrombin (Parke-Davis) were added. After incubation at 37°C for 2 h, fibrin was extracted on a wooden orange stick. The radioactivity of I nil of this fibrin-free solution was counted (B) as was the precipitate from I ml after 10% wjv trichloracetic acid had been added (D).After correction had been made for dilution, this allowed the calculation of the radioactivity of the free iodine fraction (C = B- D ) , the clottable fibrinogen (A-B) and of the circulating fibrinogen ( A - C). The 15 min sample was taken as 100% and the percentage fall of other samples was plotted on semi-logarithmic graph paper. Following initial mixing two straight lines of different slopes were formed. The first line represented the equilibration of fibrinogen between the intra- and extravascular pools and by extrapolating this to zero time the intravascular fraction was calculated. The biological half life of the fibrinogen was determined from the second slope (tt) and the fractional catabolic rate was calculated using the formula o.692/t, x intravascular fraction (McFarlane ef al, 1964). This formula is simply derived from the general equation for an exponential curve C = Co e-kt where C is the concentration at time t, C , is the initial concentration and k is the rate constant. At t+ C / C , = 0.5 and therefore k = In zit,. Nine patients without liver disease or any condition known to influence fibrinogen nietabolism were studied (with informed consent) as a control group. The mean value for the fractional catabolic rate in these patients was 20.3% (s 4.1) which compares closely with that previously reported in normal subjects (Tytgat, 1971). The following values have been classed as 'abnormal' : a ratio in any clotting test of greater than 1.3, a platelet count less than 125 ooolpl, any visible lysis produced by fresh plasma on a bovine fibrin plate after 24 h at 37"C, serum FDP greater than 2 pglnil, fibrin strands visible in the SDPS tests at two or more dilutions, and a value which lay outside the mean? 2 s determined for the nine control subjects for plasma fibrinogen (2.61-5.65 g/l.), fractional

Fibrinogen in Hepatitis


catabolic rate of fibrinogen (12.1-38.~%/day) or absolute catabolic rate of fibrinogen (1.1-3.5 giday). TABLE I. Maximum biochemical values and coagulation findings a t the time of the radioactive fibrinogen studics in the patients with viral hepatitis



I 2

3 4 S 6 7 (i) 7 (ii) 7 (iii)

bilirrrbin (,uinol/l.)

Plasma aspartate arniriotransfirnsc

718 239 85.5 59.8 44s I 59 I88 222


Prothroirrbiri tinre ratio*

Part ia 1 thrornboplastiri titne ratio*



730 700 185 260 I580


I .0

1.6 1.3 1.1 1.3 1.0


1 .O


4.5 1.1

3 .o 1.3 1.0



1.0 I .o

I04 40


* Ratio Patient's time/Control 7 Normal < 2 Pcg/ml.


Tlrrornbin clntting tinre

ratio* 1.5

1.3 1.3 1.1 1.3 1.1

+vc $-ve +vc +vc

2.5 I .0



Fibrinogen metabolism in acute hepatitis and active chronic hepatitis.

Coagulation studies, including those of radioactive fibrinogen metabolism, were performed in seven patients with acute viral hepatitis and 12 patients...
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