AIM: To investigate the relationship between certain biochemical parameters of lipid metabolism in the serum and steatosis in the liver. METHODS: The grade of steatosis (0-3) and histological activity index (HAI, 0-18) in liver biopsy specimens were correlated with serum alanine aminotransferase (ALT), total cholesterol and triglyceride levels in 142 patients with chronic hepatitis C (CH-C), and 28 patients with non-alcoholic fatty liver disease (NAFLD) without hepatitis C virus (HCV) infection. The serum parameters were further correlated with 1 797 age and sex matched control patients without any liver diseases. RESULTS: Steatosis was detected in 90 out of 142 specimens (63%) with CH-C. The ALT levels correlated with the grade of steatosis, both in patients with CH-C and NAFLD (P<0.01). Inserting the score values of steatosis as part of the HAI, correlation with the ALT level (P<0.00001) was found. The triglyceride and cholesterol levels were significantly lower in patients with CH-C (with and without steatosis), compared to the NAFLD group and to the virus-free control groups. CONCLUSION: Our study confirms the importance of liver steatosis in CH-C which correlates with lower lipid levels in the sera. Inclusion of the score of steatosis into HAI, in case of CH-C might reflect the alterations in the liver tissue more precisely, while correlating with the ALT enzyme elevation. AIM: To investigate the relationship between certain biochemical parameters of lipid metabolism in the serum and steatosis in the liver. METHODS: The grade of steatosis (0-3) and histological activity index (HAI, 0-18) in liver biopsy specimens were correlated with serum alanine aminotransferase (ALT), total cholesterol and triglyceride levels in 142 patients with chronic hepatitis C (CH-C), and 28 patients with non-alcoholic fatty liver disease (NAFLD) without hepatitis C virus Results were further correlated with 1 797 age and sex matched control patients without any liver diseases. RESULTS: Steatosis was detected in 90 out of 142 specimens (63%) with CH-C. The ALT levels correlated with the grade of steatosis, both in Patients with CH-C and NAFLD (P <0.01). Inserting the score values ​​of steatosis as part of the HAI, correlation with the ALT level (P <0.00001) was found. The triglyceride and cholesterol levels were significantly lower in patients with CH -C (with and without steatosis), compared to the NAFLD group and to the virus-free control groups. CONCLUSION: Our study confirms the importance of liver steatosis in CH-C which correlates with lower lipid levels in the sera. Inclusion of the score of steatosis into HAI, in case of CH-C might reflect the alterations in the liver tissue more precisely, while correlating with the ALT enzyme elevation.