title: Resistance trends of Bacteroides fragilis group over an 8-year period, 1997-2004, in Korea.
abstract: BACKGROUND
  Bacteroides fragilis group organisms are the most frequently isolated anaerobes in human infections. Increasing resistance to various antimicrobial agents is a significant problem in choosing appropriate antimicrobial agents to treat anaerobic infections. Periodic monitoring of the regional resistance trends of B. fragilis group isolates is needed.
  
  
  METHODS
  A total of 466 nonduplicate clinical isolates of B. fragilis group organisms (276 B. fragilis, 106 Bacteroides thetaiotaomicron, and 84 other B. fragilis group organisms) were collected during the 8-yr period from 1997 to 2004 in a Korean university hospital. Minimum inhibitory concentrations to various antimicrobial agents were determined by the CLSI agar dilution method.
  
  
  RESULTS
  Eight isolates were resistant to imipenem. Additionally, the resistance rates to cefotetan were decreased in B. thetaiotaomicron, while those for clindamycin were significantly increased compared to the rates found in previous studies. Depending on species, resistance rates were 1-4% for imipenem, 1-6% for piperacillin-tazobactam, 4-11% for cefoxitin, 33-49% for piperacillin, 14-60% for cefotetan, and 51-76% for clindamycin. No isolates were resistant to chloramphenicol or metronidazole.
  
  
  CONCLUSIONS
  Piperacillin-tazobactam, cefoxitin, imipenem, chloramphenicol, and metronidazole are still active against B. fragilis group isolates, while clindamycin no longer has a value as an empirical therapeutic agent in Korea. Furthermore, this study identified the first imipenem-resistant B. fragilis group isolates in Korea.
authors.affiliation: Department of Laboratory Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Kyoung Ho
authors.initials: KH
authors.lastname: Roh
authors.forename: Sinyoung
authors.initials: S
authors.lastname: Kim
authors.forename: Chang-Ki
authors.initials: CK
authors.lastname: Kim
authors.forename: Jong Hwa
authors.initials: JH
authors.lastname: Yum
authors.forename: Myung Sook
authors.initials: MS
authors.lastname: Kim
authors.forename: Dongeun
authors.initials: D
authors.lastname: Yong
authors.forename: Kyungwon
authors.initials: K
authors.lastname: Lee
authors.forename: June Myung
authors.initials: JM
authors.lastname: Kim
authors.forename: Yunsop
authors.initials: Y
authors.lastname: Chong
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001439:Bacteroides / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification; D001441:Bacteroides fragilis / Q000187:drug effects / Q000302:isolation & purification; D002440:Cefoxitin / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D015378:Imipenem / Q000494:pharmacology; D008795:Metronidazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D010397:Penicillanic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D010878:Piperacillin / Q000494:pharmacology; D000077725:Piperacillin, Tazobactam Drug Combination; D056910:Republic of Korea
chemical_list: D000900:Anti-Bacterial Agents; D008795:Metronidazole; D000077725:Piperacillin, Tazobactam Drug Combination; D002701:Chloramphenicol; D002440:Cefoxitin; D015378:Imipenem; D010397:Penicillanic Acid; D010878:Piperacillin