Molecular epidemiology of β-lactamases in ceftriaxone-resistant Enterobacterales bloodstream infections in the mid-Atlantic United States.

ABSTRACT: Ceftriaxone-resistant Enterobacterales remain a public health threat; contemporary data investigating their molecular epidemiology are limited. Five hundred consecutive ceftriaxone-resistant (MIC ≥ 4 µg/mL) Enterobacterales bloodstream isolates were collected between 2018 and 2022 from three Maryland hospitals. Broth microdilution confirmed antibiotic susceptibilities. Whole-genome sequencing identified extended-spectrum β-lactamase (ESBL) and ampC genes both in bacterial chromosomes (c-ampC) and on plasmids (p-ampC). Mutations in promoter or attenuator regions of the Escherichia coli c-ampC gene (i.e., bla_EC gene) with the potential to result in ampC derepression were investigated. The presence of ESBL or ampC genes was co

SUBMITTER: Hareza DA 

PROVIDER: S-EPMC11881560 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature