title: [Changes of antimicrobial resistance among clinical isolates of Escherichia coil in Shanghai 1990-2004].
abstract: OBJECTIVE
  To investigate the trend of resistance to antimicrobial agents among clinical isolates of Escherichia coli 1990-2004.
  
  
  METHODS
  Agar diffusion test was used to analyze the changes of drug susceptibility of 33,495 strains of E. coli isolated from 11 hospitals in Shanghai to 21 antimicrobial agents 1990-2004.
  
  
  RESULTS
  The resistance rates of 33,495 E.coli isolates to 21 antimicrobial agents mostly increased 1990-2004. The resistance rates to ampicillin and piperacillin increased from 69% and 30% to 85% and 71.4% respectively. The resistance rates to cephalosporins, except ceftazidime and cefepime, all increased, e. g., the resistance rates to cefazolin (24.0%-->48.3%), cefuroxime (18.0%-->45.7%), and cefaclor (33.3%-->46.8%), especially that to cefotaxime (6.0%-->35.2%). The resistance rate to fluoroquinolones increased from 11.0% to 55.4%. The resistance rate to gentamicin increased from 44.0% to 54.0%. The resistance rates to tetracycline, chloramphenicol, SMZ/TMP remained at high levels. However, ceftazidime, cefepime, imipenem, amikacin, beta-lactams/beta-lactamase inhibitors, and nitrofurantoin remained active against the E.coli isolates. The detectable rate of extended-spectrum beta-lactamase-producing strains in E. coli increased from 14.7% to 36.5%.
  
  
  CONCLUSIONS
  The trend of resistance of E. coli to commonly used antimicrobials was upward 1990-2004.
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai 200040, China.
authors.forename: Ying-yuan
authors.initials: YY
authors.lastname: Zhang
authors.forename: De-mei
authors.initials: DM
authors.lastname: Zhu
authors.forename: Fu-pin
authors.initials: FP
authors.lastname: Hu
authors.forename: Shi
authors.initials: S
authors.lastname: Wu
authors.forename: Fu
authors.initials: F
authors.lastname: Wang
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001424:Bacterial Infections / Q000382:microbiology; D002681:China; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000639:trends
chemical_list: D000900:Anti-Bacterial Agents