CTX-M and ampC β-lactamases contributing to increased prevalence of ceftriaxone-resistant Escherichia coli in Changi General Hospital, Singapore☆☆☆

Received 5 May 2009; accepted 30 August 2009. published online 05 October 2009.

Abstract

Data from an 800-bed hospital showed an increase in the incidence density of ceftriaxone-resistant Escherichia coli, from 13.1 to 21.7 per 100 000 inpatient days over a 4-year period. Detailed testing performed on 54 E. coli isolates showed blaCTX-M extended-spectrum β-lactamase (ESBL) genes (n = 37) and blaCMY-like ampC genes (n = 15). Typing data showed only limited clonal transmission in isolates with ESBL.

Keywords: AmpC, Plasmid, Health-care–associated infections, β-Lactamases, Cross-infection

a Department of Laboratory Medicine, Changi General Hospital, Singapore 529889, Singapore

b Department of Pathology, Singapore General Hospital, Singapore, 169608

c Department of Medicine, National University of Singapore, Singapore, 119074

Corresponding author. Tel.: +65-68504934; fax: +65-64269507.

☆ Tan Thean Yen, TYT, has received research funding from Wyeth Pharmaceuticals and has been an invited speaker for Wyeth Pharmaceuticals, Astra-Zeneca, and Jansson-Cilag. Hsu Li Yang, HLY, has received research funding from Wyeth Pharmaceuticals.

☆☆ Preliminary data from this study was presented as a poster at the Australian Society of Microbiology, Melbourne, July 6 to 10, 2008.

PII: S0732-8893(09)00363-0

doi:10.1016/j.diagmicrobio.2009.08.019

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