The effect of liver disease on factors V, VIII and protein C

Publisher Website
Google Scholar
Abstract
Summary. The components of the factor VIII complex were estimated by immuno‐ and bioassays in 85 patients with liver disease. The plasma concentrations of the antigens were elevated in 65% (VIII:CAg) and in 76% (VIIIR:Ag) of patients while the biological activites were elevated in only 14% (VIII:C) and 15% (VIII:RiCof). There was no correlation with C‐reactive protein, used as a measure of an acute phase reaction (χ2=0·7; P=0·1); or with severity of liver disease as judged by prothrombin ratio (P=1·0) but highest values were observed in patients with cholestatic liver disease. Following parenteral vitamin K there was a significant fall in both the biological activity of VIIIC (36%) and of VIII:CAg (38%) in 13 vitamin K deficient patients (Pn=12; normal range 0·5–1·5 units/ml) than in patients with extrahepatic cholestasis who were vitamin K deficient (1·2 ± 0·1 units/ml, Pn= 18, normal range 0·74–1·4 units/ml). There was no significant change in either protein C antigen or factor V following vitamin K.The discrepancy between the biological activity of factor VIII and the antigen levels could represent accumulation of partially degraded factor VIII or production of a hypoactive form. There is no evidence that the reduction in VIIIC and VIII:CAg following vitamin K was mediated by protein C.