Lack of plasma complement activation in severe acute alcoholic hepatitis

To investigate whether complement pathway activation contributes to the clinical and histological features of acute alcoholic hepatitis, we studied the activation of the classical and alternative pathways in patients with alcoholic hepatitis (n = 20), inactive alcoholic cirrhosis (n = 8), heavy drinkers without alcoholic liver disease (n = 10), patients with liver disease of nonalcoholic etiology (n = 11), and healthy control subjects (n = 18). Complement activation was evaluated in the alcoholic hepatitis patients by its correlation with a number of clinical and laboratory features indicative of the severity of liver injury, as well as by comparison of the patient groups. There was no significant difference in circulating C3 [1.02 g/liter, confidence interval (CI) = 0.76-1.28] or C4 (0.25 g/liter, CI = 0.17-0.33) in patients with alcoholic hepatitis when compared with the four control groups. Factor B levels (0.24 g/liter, CI = 0.21-0.27) were higher in the alcoholic hepatitis patients than the control groups (p < 0.01). However, activation of complement (given by the ratios C3d/C3, C4d/C4, and Ba/factor B) was not different in alcoholic hepatitis patients when compared with the control groups. Univariate analysis of a wide range of clinical and laboratory features in the alcoholic hepatitis subjects showed a positive correlation between plasma C3 and serum alkaline phosphatase (r = 0.68, p = 0.0014), AST (r = 0.55, p = 0.015), and gamma-glutamyltranspeptidase (r = 0.47, p = 0.035), but no correlation with clinical or laboratory features associated with high morbidity or mortality. There is no relationship between clinical or laboratory indicators of disease severity and complement activation, and it is unlikely that complement activation contributes to the clinical and histological features of alcoholic liver disease.