Characterizing <i>Escherichia coli</i> carrying plasmid-mediated AmpC β-lactamases to optimize detection in a diagnostic laboratory setting.

ABSTRACT: Plasmid-mediated AmpC β-lactamases are a cause of acquired cephalosporin resistance in Gram-negative bacteria. However, consensus regarding the optimal detection method is yet to be achieved and varies depending on local epidemiology and laboratory capacity. We determined the acquired genotypic resistance mechanisms of 250 Escherichia coli isolates with a positive AmpC screen, defined as cefoxitin MIC ≥ 8 mg/L and a positive AmpC double- disc diffusion test, using in-house designed high-resolution melt PCR, detecting plasmid-acquired genes from the CIT and DHA families. A proportion of these isolates (n = 170, 68%) underwent further genotypic characterization using whole- genome sequencing (WGS). Of 250 isolates with a positive screening test, 72 (28.8%) were determined to ca

SUBMITTER: Teng J 

PROVIDER: S-EPMC11619294 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature