Clinical evaluation of chronic liver diseases induced by different hepatitis C virus genotype in Japan, focused on the difference between genotypes III/2a and IV/2b

Abstract

It remains controversial if hepatitis C virus (HCV) genotypes in the same genetic group or type are different in the activity of viral replication and capacity to induce severe clinical disease. HCV genotypes and HCV RNA titers were determined in consecutive 264 patients with chronic liver disease in Yamaguchi, Japan. Genotype I/1a was detected in 3 (1%), II/1b in 192 (74%), III/2a in 46 (18%), IV/2b in 17 (6%) and co-infection with II/1b and III/2a in 3 (1%); HCV RNA titers in the remaining three patients were too low to be genotyped. The patients with genotype III/2a were significantly older ( P<0.05) and had lower HCV RNA titers in serum than those with genotype IV/2b ( P=0.0211; odds ratio 6.47 [95% confidence interval: 1.323–31.587]). These results indicate that, even though genotypes III/2a and IV/2b belong to the same genetic group (type) 2, they would need to be distinguished clinically because the patients’ age and HCV RNA titer in serum are both important factors in treating the patients with HCV infection.