Affiliation:
1. Pathology and Laboratory Medicine Service/113, McGuire Veterans Affairs, Medical Center, Richmond, Virginia 23249-0001
Abstract
ABSTRACT
Non-beta-lactam inhibitor-based methods were evaluated for detecting plasmid-mediated AmpC β-lactamases in
Klebsiella
spp.,
Escherichia coli
, and
Proteus mirabilis
. Using CLSI methodology and disks containing cefotetan alone and in combination with 400 μg of boronic acid, 9 of 10 positive control strains and 54 of 55 AmpC-PCR-positive clinical isolates were detected. Importantly 71% and 40% of these clinical isolates were susceptible by routine testing to ceftriaxone and ceftazidime, respectively. Boronic acid disks also enhanced detection of expanded-spectrum β-lactamases in AmpC producers.
Publisher
American Society for Microbiology
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