A Multinational Survey of Risk Factors for Infection With Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae in Nonhospitalized Patients

Clin Infect Dis. 2009 Sep 1;49(5):682-90. doi: 10.1086/604713.


Background: Infections caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are increasing in frequency and are associated with high mortality rates. Circulation of CTX-M-type ESBLs in the community is of particular concern, because it may confound standard infection-control measures.

Methods: We analyzed the results of epidemiologic studies of infection caused by ESBL-producing Enterobacteriaceae in nonhospitalized patients from 6 centers in Europe, Asia, and North America. Risk factors for infection with an ESBL-producing organism were identified by univariate and multivariate analyses.

Results: A total of 983 patient-specific isolates were reviewed (890 [90.5%] of which were Escherichia coli, 68 [6.9%] of which were Klebsiella species, and 25 [2.5%] of which were Proteus mirabilis); 339 [34.5%] of the isolates produced ESBLs. CTX-M types were the most frequent ESBLs (accounting for 65%). Rates of co-resistance to ciprofloxacin among ESBL-producing isolates were high (>70%), but significant variation was seen among centers with respect to rates of resistance to gentamicin, amoxicillin-clavulanate, and trimethoprim-sulfamethoxazole. Similar risk factors for infection with an ESBL-producing organism were found in the different participating centers. Significant risk factors, identified by multivariate analysis, were recent antibiotic use, residence in a long-term care facility, recent hospitalization, age 65 years, and male sex (area under the receiver-operator characteristic [ROC] curve, 0.80). However, 34% of ESBL-producing isolates (115 of 336 isolates) were obtained from patients with no recent health care contact; the area under the ROC curve for the multivariate model for this group of patients was only 0.70, which indicated poorer predictive value.

Conclusions: Community-acquired ESBL-producing Enterobacteriaceae are now prevalent worldwide, necessitating international collaboration. Novel approaches are required to adequately address issues such as empirical treatment for severe community-acquired infection and infection control.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Community-Acquired Infections / epidemiology
  • Community-Acquired Infections / microbiology
  • Enterobacteriaceae / drug effects
  • Enterobacteriaceae / enzymology*
  • Enterobacteriaceae Infections / epidemiology*
  • Enterobacteriaceae Infections / microbiology
  • Female
  • Global Health
  • Health Surveys
  • Humans
  • Male
  • Microbial Sensitivity Tests
  • Multivariate Analysis
  • Prevalence
  • ROC Curve
  • Risk Factors
  • beta-Lactam Resistance*
  • beta-Lactamases / biosynthesis*
  • beta-Lactamases / genetics


  • beta-Lactamases