Clinical and bacteriological effects of pivmecillinam for ESBL-producing Escherichia coli or Klebsiella pneumoniae in urinary tract infections

J Antimicrob Chemother. 2014 Mar;69(3):769-72. doi: 10.1093/jac/dkt404. Epub 2013 Oct 9.


Objectives: The prevalence of urinary tract infections (UTIs) caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae is increasing and the therapeutic options are limited, especially in primary care. Recent indications have suggested pivmecillinam to be a suitable option. Here, we evaluated the clinical and bacteriological effects of pivmecillinam in UTIs caused by ESBL-producing Enterobacteriaceae.

Methods: We carried out a prospective follow-up of 39 patients diagnosed with UTI caused by ESBL-producing Enterobacteriaceae, initiated on pivmecillinam. The patients were from general practice (n = 29) or admitted to hospitals (n = 10) in the Copenhagen area, Denmark (n = 30) or Halland, Sweden (n = 9). Both patients and physicians were asked to complete a questionnaire on the pretreatment signs and symptoms. Patients were asked to send in two more urine samples for culture examination, together with questionnaires for clinical effect, 2-6 and 10-20 days, respectively, after end of treatment.

Results: Of the 39 patients included, 30 received a treatment regimen of 400 mg of pivmecillinam three times a day and 9 received 200 mg three times a day. All isolates were susceptible to mecillinam. The bacteriological cure rate was 79% (31/39); 80% (24/30) and 78% (7/9) for 400 and 200 mg three times a day, respectively. Relapse, i.e. ESBL-producing bacteria in the second control urine after previous bacteriological cure, was seen in five patients. Clinical cure was evaluable in 19 patients; 16 had a clinical effect (84%).

Conclusions: Pivmecillinam was proven bacteriologically and clinically effective for treatment of lower UTIs caused by ESBL-producing Enterobacteriaceae.

Keywords: Enterobacteriaceae; antimicrobal therapy; community-acquired infections; mecillinam; multidrug resistance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Amdinocillin Pivoxil / therapeutic use*
  • Anti-Bacterial Agents / therapeutic use
  • Denmark
  • Escherichia coli / enzymology*
  • Escherichia coli / isolation & purification
  • Escherichia coli Infections / drug therapy*
  • Escherichia coli Infections / microbiology
  • Escherichia coli Infections / pathology
  • Female
  • Follow-Up Studies
  • Humans
  • Klebsiella Infections / drug therapy*
  • Klebsiella Infections / microbiology
  • Klebsiella Infections / pathology
  • Klebsiella pneumoniae / enzymology*
  • Klebsiella pneumoniae / isolation & purification
  • Male
  • Middle Aged
  • Netherlands
  • Surveys and Questionnaires
  • Sweden
  • Treatment Outcome
  • Urinary Tract Infections / drug therapy*
  • Urinary Tract Infections / microbiology
  • Urine / microbiology
  • Young Adult
  • beta-Lactamases / metabolism*


  • Anti-Bacterial Agents
  • Amdinocillin Pivoxil
  • beta-Lactamases