Background and Aims: Neopterin is a proinflammatory indicator that plays a role in cell-mediated immunity, and elevated concentrations of neopterin indicate the presence of interferon-γ in body fluids. In this study, neopterin concentrations were determined in patients with a virus-induced chronic liver disease (chronic hepatitis, liver cirrhosis, and hepatocellular cancer), inactive hepatitis B virus carriers, and in a healthy control group to assess whether neopterin can be used as a disease marker in patients with virus-induced chronic liver disease. Materials and Methods: A total of 110 subjects (42 females and 68 males, with an average age of 44±8.90 years) were included in this study. Of these patients, 33 had chronic hepatitis; 22, liver cirrhosis; 22, hepatoma; 18, inactive hepatitis B virus carriers; and 15 were included in the healthy control group. Neopterin levels were measured before and after interferon treatment in patients with chronic hepatitis. Data collected among the groups were analyzed statistically using the Mann-Whitney test, considering p < 0.05 as statistically significant. Results: Neopterin concentrations and gender showed no statistically significant correlation. Patients with cirrhosis, hepatocellular cancer, and chronic hepatitis had statistically significantly higher neopterin levels than the healthy control and healthy carrier groups. A positive correlation was observed between neopterin levels and other disease activity indicators such as aspartate transaminase, alanine transaminase, hepatitis B virus deoxyribonucleic acid, hepatitis C virus ribonucleic acid, erythrocyte sedimentation rate, and C-reactive protein levels, and their levels were also high. Although 14 patients, who were also evaluated after interferon treatment, showed good response to the treatment, no statistically significant correlation was observed between their neopterin levels and disease activity indicator levels. Conclusion: Neopterin concentrations were found to be significantly higher in patients with inflammation than in inactive hepatitis B virus carriers who had no ongoing inflammatory activity and in the healthy control group. No correlation was detected between neopterin levels and hepatitis B virus deoxyribonucleic acid and hepatitis C virus ribonucleic acid levels in patients who received interferon treatment and benefitted from it. Although neopterin levels indicate inflammatory activity in cases of chronic hepatitis, liver cirrhosis, and hepatocellular cancer, additional studies are necessary to determine its usefulness in clinical practice.
