Nosocomial bloodstream infections caused by Escherichia coli and Klebsiellapneumoniae resistant to third-generation cephalosporins, Finland, 1999–2013: Trends, patient characteristics and mortality

Abstract

Background: Few systematically collected multi-centre surveillance data on nosocomial bloodstream infections (BSI) caused by extended-spectrum β-lactamase (ESBL) producing Escherichia coli or Klebsiella pneumoniae have been published. Aim: To evaluate trends, patient characteristics and mortality of such infections, nosocomial BSI data reported by the 4–17 hospitals participating in the prospective laboratory-based surveillance during 1999–2013 were analysed. Methods: Data were collected by local infection control nurses, patient-days were obtained from the hospital’s administrative database, and dates of deaths from the population registry. Resistance to third-generation cephalosporins was further examined in the national reference laboratory. Findings: A total of 16 028 nosocomial BSIs were identified; 2217 (14%) were caused by E. coli and 661 (4%) by K. pneumoniae; 207 (7%) were non-susceptible to third-generation cephalosporins, with an increasing trend from 0% in 1999 to 17% in 2013. Patient characteristics did not differ significantly between BSIs caused by third-generation susceptible and resistant E. coli and K. pneumonia, but the case fatality tended to be higher. Most (88%) of the isolates reported as non-susceptible to third-generation cephalosporins had ESBL phenotype, CTX-M (79%) being the most common enzyme. Conclusion: A sharp increase in nosocomial BSIs caused by ESBL producing bacteria was observed. Identification of patients for screening pose a challenge, emphasising the role of infection control guidelines and antibiotic policy in prevention

Keywords:

• Nosocomial
• blood stream infection
• surveillance
• ESBL

Acknowledgements

We warmly thank the microbiological laboratories of the participating hospitals for their efforts in retrieving and sending us the cephalosporin resistant nosocomial blood isolates for this study.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.