Hepatitis C virus (HCV) is classified into different genotypes based on sequence differences in the viral genome. Several previous studies have suggested that some genotypes, generally type 1a and 1b, are associated with more advanced liver disease. For example, Zein et al. (1996) recently showed that genotypes 1a and 1b, the most prevalent in the United States, are associated with more severe liver disease. In this study, the authors studied 429 patients in Italy with chronic hepatitis C including 109 with cirrhosis. The patients with cirrhosis were followed prospectively to assess the role of HCV genotype on disease outcome.
Genotype 1 (mainly 1b) was detected in 46% of patients without cirrhosis and 43% with cirrhosis (P not significant).
Genotype 2 (mainly 2a) was detected in 32% of individuals without cirrhosis and 27.5% with cirrhosis (P not significant). Genotype 3 was detected in 10% of patients without cirrhosis and 2% with cirrhosis (P < 0.005).
Mixed genotype infections were found in 5.5% of individuals, all of whom had cirrhosis. During a mean follow-up of the patients with cirrhosis for 67 months, 38.5% had either worsening of Child’s stage, underwent liver transplantation, developed hepatocellular carcinoma or died. The probability of developing each or at least one of these events did not differ in relation to the genotype of infecting HCV, except for a higher incidence of death in individuals with mixed genotype infections. These results, which are in contrast to those of several other studies, suggest that HCV genotype does not have a significant effect on the severity and progression of liver disease in patients with chronic hepatitis.
Copyright, 1995, Columbia University Division of GastroenterologyBy Howard J. Worman, M. D.
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