title: Clinical features of hepatitis B virus genotype A in Japanese patients.
abstract: BACKGROUND
  Hepatitis B virus (HBV) genotype A is predominant in northern Europe and central Africa. In the present study, we examined the clinical features associated with HBV genotype A disease in the Tokyo metropolitan area.
  
  
  METHODS
  We investigated 53 cases of HBV surface antigen (HBsAg)-positive Japanese patients with HBV genotype A. The 53 cases were further classified as to their serum alanine aminotransferase (ALT) status being within the normal range (asymptomatic carriers, n = 17), chronic hepatitis (n = 15), liver cirrhosis (n = 4), and acute hepatitis (n = 17).
  
  
  RESULTS
  Chronic hepatitis patients had significantly higher HBV DNA levels (P = 0.003) and hepatitis B e antigen (HBeAg) positivity rates at the initial visit than did asymptomatic carriers or patients with liver cirrhosis (P = 0.003 and P = 0.054, respectively). The efficacy of treatment (HBeAg seroconversion rate) was 75% in 12 chronic hepatitis patients, which was excellent. A family history of HBsAg positivity was identified in eight (15%) families (five asymptomatic carriers, three with chronic hepatitis). However, none of the mothers in the study was positive for HBV genotype A.
  
  
  CONCLUSIONS
  Maternal transmission of HBV has often been reported in Japan, but our present findings suggest that horizontal infection of HBV genotype A is more prevalent in the Tokyo metropolitan area. Our data indicate that HBV genotype A exhibits a mode of infection different from that of conventional HBV previously seen in Japan.
authors.affiliation: Research Institute for Hepatology, Toranomon Hospital, 1-3-1 Kajigaya, Takatsu-ku, Kawasaki 213-8587, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Yasuji
authors.initials: Y
authors.lastname: Arase
authors.forename: Kenji
authors.initials: K
authors.lastname: Ikeda
authors.forename: Akihito
authors.initials: A
authors.lastname: Tsubota
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Hosaka
authors.forename: Satoshi
authors.initials: S
authors.lastname: Saitoh
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Suzuki
authors.forename: Norio
authors.initials: N
authors.lastname: Akuta
authors.forename: Takashi
authors.initials: T
authors.lastname: Someya
authors.forename: Marie
authors.initials: M
authors.lastname: Matsuda
authors.forename: Junko
authors.initials: J
authors.lastname: Sato
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Kumada
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004279:DNA, Viral / Q000032:analysis; D005192:Family Health; D005260:Female; D005838:Genotype; D006509:Hepatitis B / Q000276:immunology / Q000821:virology*; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged
chemical_list: D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens