title: Natural history of chronic hepatitis C: genotype 1 versus genotype 6.
abstract: OBJECTIVE
  Data on the natural history of chronic hepatitis C virus (HCV) genotype 6 is lacking.
  
  
  METHODS
  We compared the natural history of 138 HCV genotype 1 patients (median age: 50) with 78 HCV genotype 6 patients (median age: 46.5). Baseline demographic data including gender, route of transmission, liver biochemistry, HCV RNA levels, and serial alanine aminotransferase (ALT) levels were compared. The rate of development of complications and mortality were also analyzed.
  
  
  RESULTS
  A total of 71.7% and 8.7% of genotype 1 patients were infected through blood transfusion and intravenous drug addiction, respectively, compared with 56.4% and 28.2% for genotype 6 patients, respectively (p<0.05). There were no differences in the baseline liver biochemistry in terms of ALT, albumin, bilirubin, alpha-fetoprotein (AFP), and HCV RNA levels between the two groups. Comparison of the proportion of normal and abnormal ALT levels between the two groups showed no statistical difference (p=0.121). There was also no statistical difference in the cumulative rate of development of cirrhotic complications and hepatocellular carcinoma (p=0.358) and mortality (p=0.649) between the two groups.
  
  
  CONCLUSIONS
  HCV genotype 1 patients were largely infected through blood transfusion, while a statistically larger proportion of genotype 6 patients were infected through intravenous drug injection. Both genotypes have comparable liver biochemistry, HCV viral load, and similar rates of development of cirrhotic complications and mortality.
authors.affiliation: Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
authors.forename: Wai-Kay
authors.initials: WK
authors.lastname: Seto
authors.forename: Ching-Lung
authors.initials: CL
authors.lastname: Lai
authors.forename: James
authors.initials: J
authors.lastname: Fung
authors.forename: Ivan
authors.initials: I
authors.lastname: Hung
authors.forename: John
authors.initials: J
authors.lastname: Yuen
authors.forename: John
authors.initials: J
authors.lastname: Young
authors.forename: Danny Ka-Ho
authors.initials: DK
authors.lastname: Wong
authors.forename: Man-Fung
authors.initials: MF
authors.lastname: Yuen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000209:etiology; D002648:Child; D015331:Cohort Studies; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D019698:Hepatitis C, Chronic / Q000150:complications / Q000378:metabolism / Q000821:virology*; D054884:Host-Pathogen Interactions; D006801:Humans; D053208:Kaplan-Meier Estimate; D008103:Liver Cirrhosis / Q000209:etiology; D008113:Liver Neoplasms / Q000209:etiology; D008297:Male; D008875:Middle Aged; D013045:Species Specificity; D055815:Young Adult