AIM:To evaluate serum neopterin levels and their correlations with liver function tests and histological grade in children with hepatitis-B-related chronic liver disease. METHODS:The study population comprised 48 patients with chronic active hepatitis B,32 patients with hepatitis-B-related active liver cirrhosis and 40 normal controls. Serum neopterin was measured using an enzyme-linked immunosorbent assay. RESULTS:The mean ± SD serum neopterin levels were 14.2 ± 5.6 nmol/L in patients with chronic hepatitis,20.3 ± 7.9 nmol/L in patients with liver cirrhosis and 5.2 ± 1.4 nmol/L in control group. Serum neopterin levels were signif icantly higher in patients with chronic hepatitis (P = 0.005) and cirrhosis patients (P = 0.008),than in control subjects. Cirrhotic patients had signif icantly higher serum neopterin levels than patients with chronic hepatitis (P = 0.004). There was a positive correlation between serum neopterin levels and alanine aminotransferase levels in patients with chronic hepatitis (r = 0.41,P = 0.004) and cirrhotic patients (r = 0.39,P = 0.005). Positive correlations were detected between serum neopterin levels and inflammatory score in patients with chronic hepatitis (r = 0.51,P = 0.003) and cirrhotic patients (r = 0.49,P = 0.001). CONCLUSION:Our results suggest that serum neopterin levels can be considered as a marker of inflammatory activity and severity of disease in children with hepatitis-B-related chronic liver disease. AIM: To evaluate serum neopterin levels and their correlations with liver function tests and histological grade in children with hepatitis-B-related chronic liver disease. METHODS: The study population 48 patients with chronic active hepatitis B, 32 patients with hepatitis-B- related active liver cirrhosis and 40 normal controls. RESULTS: The mean ± SD serum neopterin levels were 14.2 ± 5.6 nmol / L in patients with chronic hepatitis, 20.3 ± 7.9 nmol / L in patients with liver cirrhosis and 5.2 ± 1.4 nmol / L in control group. Serum neopterin levels were signif icantly higher in patients with chronic hepatitis (P = 0.005) and cirrhosis patients (P = 0.008), than in control subjects. Cirrhotic patients had signif icantly higher serum neopterin levels than patients with chronic hepatitis (P = 0.004). There was a positive correlation between serum neopterin levels and alanine aminotransferase levels in patients with Positive correlations were detected between serum neopterin levels and inflammatory score in patients with chronic hepatitis (r = 0.51, P = 0.003) and cirrhotic patients (r = 0.49, P = 0.001). CONCLUSION: Our results suggest that serum neopterin levels can be considered as a marker of inflammatory activity and severity of disease in children with hepatitis-B-related chronic liver disease.