Mechanisms of carbapenem resistance among a collection of Enterobacteriaceae clinical isolates in a Texas city.

Department of Medicine, San Antonio Military Medical Center, Fort Sam Houston, Texas 78234, USA.
Diagnostic microbiology and infectious disease (Impact Factor: 2.45). 04/2010; 66(4):445-8. DOI:10.1016/j.diagmicrobio.2009.11.013
Source: PubMed

ABSTRACT Fourteen Enterobacteriaceae isolates with ertapenem MIC >2 mg/mL were analyzed to identify mechanisms of resistance. All isolates produced extended-spectrum beta-lactamase or AmpC beta-lactamase with variable, but decreased, expression of outer membrane proteins. One Enterobacter cloacae produced derepressed AmpC beta-lactamase, 1 Escherichia coli expressed plasmid-mediated AmpC beta-lactamase, and 1 E. cloacae produced a carbapenemase.

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