Clinical significance of extended-spectrum β-lactamases

Abstract

The spread of extended-spectrum β-lactamases (ESBLs) in nosocomial and community-acquired enterobacteria is an important challenge for clinicians as the therapeutic options for these organisms are limited. The emergence of ESBL-producing Escherichia coli in the community, associated with the spread of CTX-M ESBL, is one of the most significant epidemiologic changes in infectious diseases during recent years. The epidemiology of these infections is complex and combines the expansion of mobile genetic elements with clonal spread. Infections caused by ESBL producers are associated with increased mortality, length of stay and increased cost. An inadequate empirical therapy for serious infections caused by these organisms is independently associated with increased mortality. Carbapenems are the drugs of choice for serious infections caused by ESBL-producing organisms but their overuse is a cause of concern.

Keywords::

• antimicrobial therapy
• β-lactamase
• Escherichia coli
• extended-spectrum β-lactamase
• Klebsiella pneumoniae
• mortality
• risk factor

Financial disclosures & acknowledgements

J Rodríguez-Baño has been a consultant for Chiron, Wyeth, Merck and Pfizer, has served as a speaker for Wyeth, Merck, Pfizer, AstraZeneca and GlaxoSmithKline, and has received research support from Wyeth. A Pascual has been a consultant for Merck and Pfizer, has served as a speaker for Wyeth, AstraZeneca, Merck and Pfizer, and has received research support from Merck, Wyeth and Pfizer.

J Rodríguez-Baño and A Pascual are supported by Ministerio de Sanidad y Consumo, Instituto de Salud Carlos III – FEDER, Spanish Network for the Research in Infectious Diseases (grant REIPI RD06/0008) and FIS (grant PI070190). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.