[Detection and typing of hepatitis C RNA in liver biopsies in comparison with histopathology].

Total RNA of 55 frozen liver biopsies were extracted and tested for the presence of HCV RNA and the genotype by RT-PCR using primers of the 5' non-coding region and a type specific primer set for HCV genotyping. In paralell, the activity of chronic hepatitis, the stage of fibrosis as well as chracteristic features of chronic hepatitis C were evaluated by conventional histology. HCV RNA was detected in 49 (89.1%) of 55 liver specimen by either primer set and genotyping was successful in 42 (76.4%) of liver biopsies. The samples were divided in 3 groups: Group A consisted of specimens infected with genotypes 1a, 2a and 2b (n = 13), Group B contained biopsies infected with genotype 1b (n = 24) and Group C were biopsies with two or no detectable genotype. The histology showed a significant higher degree of fibrosis/cirrhosis in Group B (genotype 1b) compared to Group A (11/24 vs. 0/13, p = 0.011). In addition, an advanced fibrosis/cirrhosis was found more often in Group C than B, however, this difference was not significant (5/15 vs. 0/13, p = 0.072). No difference was seen between the three groups with respect to the activity of chronic hepatitis, presence of lymphoid follicles, bile duct lesions or steatosis. We conclude that HCV RNA can readily be detected and typed in frozen liver tissue. Patients infected with HCV genotype 1b have an increased risk developing liver fibrosis and cirrhosis.