Comparative in-vitro activity of cefaclor against urinary tract isolates of Escherichia coli

J Antimicrob Chemother. 1996 Jul;38(1):59-66. doi: 10.1093/jac/38.1.59.


Insusceptibility levels of cefaclor and other commonly prescribed antibiotics were determined for 489 consecutive hospital and community-associated urinary tract isolates of Escherichia coli from the Nottingham area of the UK. Significant resistance (MIC of > or = 8 mg/L) to cefaclor was found to be uncommon in the UK, with insusceptibility percentages as low as 1.5% and 1.4% amongst hospital and community isolates, respectively. When compared with other antimicrobials used commonly for treating urinary tract infection, only ciprofloxacin showed greater activity, though cefaclor showed significantly greater in-vitro activity than cephalexin, ampicillin and trimethoprim. Only seven isolates were insusceptible to cefaclor at a concentration of 8 mg/L. Each of these isolates produced a beta-lactamase, but it is unlikely that beta-lactamase production was the sole reason for insusceptibility since these isolates were also insusceptible to co-amoxiclav. Cefaclor compared extremely well with co-amoxiclav against ampicillin-insusceptible isolates, with none of the pharmacokinetic difficulties and considerations associated with the use of beta-lactam:beta-lactamase inhibitor combinations. Cefaclor appears to be a useful cost-effective alternative to current therapeutic options, particularly for long-term low-dose treatment of recurrent urinary tract infection in those geographical areas where the likelihood of resistance to other possible agents is becoming unacceptably high.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ampicillin / pharmacology
  • Cefaclor / therapeutic use*
  • Cephalosporins / therapeutic use*
  • Community-Acquired Infections / drug therapy*
  • Community-Acquired Infections / microbiology
  • Escherichia coli / drug effects*
  • Escherichia coli / isolation & purification
  • Humans
  • Microbial Sensitivity Tests
  • Penicillins / pharmacology
  • Urinary Tract Infections / drug therapy*
  • Urinary Tract Infections / microbiology


  • Cephalosporins
  • Penicillins
  • Cefaclor
  • Ampicillin