title: Change of antimicrobial susceptibility among Escherichia coli strains isolated from female patients with community-onset acute pyelonephritis.
abstract: OBJECTIVE
  There is a concern on which antimicrobials are appropriate as empirical agents for community-onset acute pyelonephritis (APN) in regions where the fluoroquinolone resistance rate is high, such as in Korea.
  
  
  METHODS
  Three hundred and two strains of E. coli in 2001-2002 and 349 strains in 2008-2009 were isolated from the urine cultures of female adult APN patients, and the antimicrobial susceptibility was compared according to each study period. All the patients were classified as uncomplicated or complicated APN, and a subgroup analysis was done thereafter.
  
  
  RESULTS
  The E. coli strains isolated in 2008-2009 showed improved susceptibility to trimethoprim-sulfamethoxazole compared to those isolated in 2001-2002. However, the third generation cephalosporin and gentamicin susceptibility was worsened. Of the 232 isolates from the uncomplicated APN patients, there was no difference between the two different time periods. On the other hand, of the 419 isolates from the complicated APN patients, the susceptibility to third generation cephalosporin, gentamicin and ciprofloxacin was significantly worsened.
  
  
  CONCLUSIONS
  The antimicrobial susceptibility of E. coli changed over the study period, however, this change occurred mainly in the complicated APN patients. In Korea, ciprofloxacin is still useful as an empirical agent for uncomplicated APN patients, but this is not the case for patients with complicated APN because of high resistance rate to ciprofloxacin in these patients. For the complicated APN patients, the rate of resistance to ciprofloxacin is already more than 30%.
authors.affiliation: Department of 1Infectious Diseases, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Seung-Kwan
authors.initials: SK
authors.lastname: Lim
authors.forename: In Whee
authors.initials: IW
authors.lastname: Park
authors.forename: Wee Gyo
authors.initials: WG
authors.lastname: Lee
authors.forename: Hyun Kyung
authors.initials: HK
authors.lastname: Kim
authors.forename: Young Hwa
authors.initials: YH
authors.lastname: Choi
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002939:Ciprofloxacin / Q000627:therapeutic use*; D017714:Community-Acquired Infections / Q000188:drug therapy* / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000382:microbiology; D005260:Female; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy / Q000382:microbiology; D011704:Pyelonephritis / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D002939:Ciprofloxacin