In order to investigate whether a difference might exist in blood cholesterol and its subtractions between patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection, serum cholesterol, HDL-cholesterol, triglycerides and common liver function tests were measured in 138 patients (92 male, 46 female) with biopsy-proven chronic viral hepatitis without cirrhosis. Twenty-four had hepatitis B and 114 hepatitis C. Mean serum cholesterol was lower in HCV-infected in comparison to HBV-infected patients (175 +/- 36 mg/dl vs. 189 +/- 28 mg/dl, p < 0.05). On multivariate analysis, etiology of hepatitis appeared to be associated with the value of serum cholesterol, independently of age, sex and liver synthetic function (improvement of chi-square 4.40, p < 0.05). In patients with HBV infection, circulating tumor necrosis factor-alpha demonstrated a correlation with serum triglycerides (p = 0.618) and an inverse correlation with serum HDL-cholesterol (p = -0.456); in the group of patients with HCV infection, interleukin-6 correlated with triglycerides (p = 0.370) and HDL-cholesterol (p = -0.355). Thus, differences in the mechanisms of liver damage and of viral clearance in hepatitis C in comparison to hepatitis B, reflected in these patients by the levels of circulating cytokines, may be mirrored by differences in their blood lipid composition.