Abstract
We identified two beta-lactamase-positive enterococci. One strain was high-level (MIC, greater than 2,000 microgram/ml) gentamicin resistant; the other was not (MIC, 12.5 microgram/ml). beta-Lactamase production was extrachromosomally mediated in both strains, and both strains showed an inoculum effect reversed by beta-lactamase inhibitors. The strain lacking high-level gentamicin resistance showed synergistic killing with a combination of penicillin, clavulanic acid, and gentamicin.
MeSH Terms
Ampicillin/pharmacology
Clavulanic Acid
Clavulanic Acids/pharmacology
Drug Resistance, Microbial
Drug Synergism
Enterococcus faecalis/drug effects,enzymology,genetics
Gentamicins/pharmacology
Penicillinase/biosynthesis
Penicillins/pharmacology
Phenotype
R Factors
Sulbactam/pharmacology
beta-Lactamase Inhibitors
Chemicals
Clavulanic Acids
Gentamicins
Penicillins
beta-Lactamase Inhibitors
Clavulanic Acid
Ampicillin
Penicillinase
Sulbactam
Authors & Affiliations
3 authors, click to expand affiliations / ORCID
Patterson J E
Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06510.
Masecar B L
Zervos M J
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