Genotypic variation, clinical and histological characteristics of chronic hepatitis C detected at blood donor screening.

Since blood donor screening for the hepatitis C virus (HCV) began in 1991 a large number of seropositive subjects have been detected and several reports have suggested a high prevelance of liver disease. The aim of this study was to evaluate the severity of liver disease in HCV-positive blood donors in terms of the clinical, biochemical and histological abnormalities and to investigate the relationships between these features and the mode of transmission, duration of infection and viral genotype. We evaluated 54 consecutive blood donors who were positive for HCV both on serological testing and polymerase chain reaction. Twenty-three (43%) had a history of intravenous drug abuse and 17 (31%) had received blood transfusions. In only two (4%) was no risk factor identified. The mean duration of infection in those with a clear history of HCV exposure was 12 years. Eighty-three percent were HCV genotypes 1 or 3. All had abnormal liver biopsies with chronic hepatitis and several patients had periportal or portal-portal fibrous septa, but there was none with architectural distortion or cirrhosis. There was no correlation between severity of liver disease and duration of HCV infection, mode of transmission or viral genotype. In the majority of HCV carriers detected at donor screening there is a chronic hepatitis with bridging necrosis in one third, but the degree of fibrosis is minimal and cirrhosis was not present in our patients. The long period of infection of many patients suggests that irreversible liver injury does not necessarily develop at an early stage despite persistent infection.