title: Do differences exist between chronic hepatitis C genotypes 2 and 3?
abstract: BACKGROUND
  Six genotypes of the hepatitis C virus (HCV) have been identified thus far, and their distribution is well defined. Genotype 1, which is the most prevalent worldwide, is always compared to genotypes 2 and 3, particularly in terms of treatment response. However, little is known about the differences between genotypes 2 and 3 because these genotypes are analyzed together in most studies. Therefore, the aim of this study was to evaluate differences in the clinical, epidemiological, laboratory, and histological parameters between HCV-2 and HCV-3.
  
  
  METHODS
  Patients with chronic hepatitis C infected with genotypes 2 and 3 were studied retrospectively and compared according to clinical, laboratory, and histological aspects. Hepatitis C virus-ribonucleic acid (HCV-RNA) was analyzed quantitatively by TaqMan® real-time PCR, and the HCV genotype was determined by sequencing the 5'-untranslated region.
  
  
  RESULTS
  A total of 306 patients with chronic HCV-2 (n=50) and HCV-3 (n = 256) were studied. Subtype 2b (n=17/50) and subtype 3a (n=244/256) were the most prevalent among patients infected with HCV-2 and HCV-3, respectively. The mean age was 47 ± 10 years, and there was a predominance of men in the group studied (61%). Comparative analysis between HCV-2 and HCV-3 showed a younger age (p=0.002), less prevalence of arterial hypertension (p=0.03), higher serum albumin levels (p=0.01), more advanced stage of liver fibrosis (p=0.03), and higher frequency of steatosis in patients with HCV-3 (p=0.001). After multivariate regression analysis, all the variables, except serum albumin, remained as variables associated with HCV-3 in the final model.
  
  
  CONCLUSIONS
  Clinical and histological differences exist between HCV-2 and HVC-3, which suggests the need for separate analyses of these genotypes.
authors.affiliation: Departamento de Gastroenterologia, Unidade de Hepatologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Isaura Cunha
authors.initials: IC
authors.lastname: Melo
authors.affiliation: Departamento de Gastroenterologia, Unidade de Hepatologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Maria Lucia Gomes
authors.initials: ML
authors.lastname: Ferraz
authors.affiliation: Departamento de Medicina Interna, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
authors.forename: Renata Mello
authors.initials: RM
authors.lastname: Perez
authors.affiliation: Departamento de Gastroenterologia, Unidade de Hepatologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Christine Takemi
authors.initials: CT
authors.lastname: Emori
authors.affiliation: Departamento de Gastroenterologia, Unidade de Hepatologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Silvia Naomi de Oliveira
authors.initials: SN
authors.lastname: Uehara
authors.affiliation: Departamento de Gastroenterologia, Unidade de Hepatologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Roberto José
authors.initials: RJ
authors.lastname: de Carvalho-Filho
authors.affiliation: Departamento de Gastroenterologia, Unidade de Hepatologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Antonio Eduardo Benedito
authors.initials: AE
authors.lastname: Silva
authors.affiliation: Departamento de Gastroenterologia, Unidade de Hepatologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Ivonete Sandra
authors.initials: IS
authors.lastname: de Souza e Silva
mesh_terms: D018450:Disease Progression; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics*; D019698:Hepatitis C, Chronic / Q000473:pathology / Q000821:virology*; D006801:Humans; D008103:Liver Cirrhosis / Q000821:virology; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D012189:Retrospective Studies
chemical_list: D012367:RNA, Viral