Efficacy of empirical therapy with non-carbapenems for urinary tract infections with extended-spectrum beta-lactamase-producing Enterobacteriaceae

Int J Infect Dis. 2014 Dec;29:91-5. doi: 10.1016/j.ijid.2014.08.018. Epub 2014 Oct 24.


Objectives: Carbapenems are first-line agents for severe infections with extended-spectrum beta-lactamase (ESBL)-producing bacteria. The use of carbapenems, however, is associated with the emergence of resistant organisms. We investigated the effects of empirical therapy with non-carbapenems on urinary tract infections (UTIs) with ESBL-producing Enterobacteriaceae in a hospital where antimicrobial stewardship has been established.

Methods: This retrospective chart review was undertaken at a tertiary care hospital where antimicrobial stewardship and restriction of carbapenems has been established. Patients with a UTI with ESBL-producing Enterobacteriaceae were stratified into susceptible and non-susceptible therapy groups according to the susceptibility of the causative organism to the initial antimicrobial therapy. Outcome measures were the duration of antimicrobial therapy, 14-day mortality, infection-related mortality, and clinical cure.

Results: Of 90 patients, 30 (33.3%) exhibited susceptible therapy. However, no significant difference was observed in the duration of antimicrobial therapy, 14-day mortality, infection-related mortality, or clinical cure between the susceptible and non-susceptible groups. Multivariate analyses revealed that the independent risk factor for 14-day morality was the use of immunosuppressive agents (odds ratio 5.23, 95% confidence interval 1.26-24.04; p=0.023).

Conclusions: Non-carbapenem therapy against UTIs with ESBL-producing Enterobacteriaceae does not pose a significant risk to patients who are not taking immunosuppressive agents.

Keywords: Beta-lactamases; Carbapenems; Cefmetazole; Cephamycins; Urinary tract infections.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / therapeutic use*
  • Carbapenems / therapeutic use
  • Enterobacteriaceae / drug effects
  • Enterobacteriaceae / enzymology*
  • Enterobacteriaceae Infections / drug therapy*
  • Enterobacteriaceae Infections / microbiology
  • Enterobacteriaceae Infections / mortality
  • Female
  • Humans
  • Immunosuppressive Agents / therapeutic use
  • Male
  • Middle Aged
  • Retrospective Studies
  • Urinary Tract Infections / drug therapy*
  • Urinary Tract Infections / microbiology
  • Urinary Tract Infections / mortality
  • beta-Lactamases / biosynthesis*


  • Anti-Bacterial Agents
  • Carbapenems
  • Immunosuppressive Agents
  • beta-Lactamases