The relation between interferon-gamma (IFN-γ) levels and the severity of liver diseases through fibrosis, cirrhosis, and hepatocellular carcinoma (HCC) has not been fully clarified. Thus, we aimed to characterize IFN-γ levels in liver-diseased patients. IFN-γ levels were determined by Western-blot and ELISA in sera from 30 healthy individuals, 53 patients with non-significant fibrosis (F0-F1), 47 with moderate/severe fibrosis (F2-F3), 44 cirrhotic patients (F4), and 50 with HCC. Enhanced levels of IFN-γ were associated with the progression of liver disease. The differences were statistically significant (P < 0.0001) when patients with F2-F3, F4, or HCC were compared with F0-F1 or healthy controls. The increase in IFN-γ was associated with HCC (OR = 0.98, 95% CI 0.97-0.99, P = 0.002). There was no statistically significant association between IFN-γ levels and HCV-RNA (IU/ml) (r = 0.1, P = 0.43) or HCV-NS4 (µg/mL) (r = 0.1, P = 0.17). There was significant (P < 0.0001) association between IFN-γ levels and the fibrosis stages and activity, albumin, platelet count, total bilirubin, and international normalized ratio (INR). In conclusion, elevated concentrations of IFN-γ represent a characteristic feature of liver disease severity regardless of underlying disease. Significant correlations with indices of hepatic dysfunction suggest that enhanced IFN-γ levels represent a consequence of liver dysfunction rather than of inflammatory disease.
Keywords: hepatocellular carcinoma; interferon gamma; liver cirrhosis; liver disease; liver fibrosis.