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In vitro activity of meropenem-vaborbactam plus aztreonam against metallo-β-lactamase-producing Klebsiella pneumoniae.

ABSTRACT: We evaluated the in vitro activity of meropenem-vaborbactam plus aztreonam (MEV-ATM) against 140 metallo-β-lactamase (MBL)-producing Klebsiella pneumoniae isolates. Among them, 25 isolates (17.9%) displayed minimum inhibitory concentrations (MIC) ≥ 8 µg/mL, while 112 (80.0%) had MIC ≤ 2 µg/mL. Genomic analysis and subsequent gene cloning experiments revealed OmpK36 134-135GD-insertion and increased carbapenemase gene (bla_NDM-1 and bla_OXA-48-like) copy numbers are the main factors responsible for MEV-ATM non-susceptibility. Notably, MEV-ATM is actively against aztreonam-avibactam-resistant mutants due to CMY-16 mutations.

SUBMITTER: Cienfuegos-Gallet AV

PROVIDER: S-EPMC10988999 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature

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In vitro activity of meropenem-vaborbactam plus aztreonam against metallo-β-lactamase-producing Klebsiella pneumoniae.

Cienfuegos-Gallet Astrid V AV Shashkina Elena E Chu Tingyu T Zhu Zhichen Z Wang Bingjie B Kreiswirth Barry N BN Chen Liang L

Antimicrobial agents and chemotherapy 20240301 4

We evaluated the in vitro activity of meropenem-vaborbactam plus aztreonam (MEV-ATM) against 140 metallo-β-lactamase (MBL)-producing Klebsiella pneumoniae isolates. Among them, 25 isolates (17.9%) displayed minimum inhibitory concentrations (MIC) ≥ 8 µg/mL, while 112 (80.0%) had MIC ≤ 2 µg/mL. Genomic analysis and subsequent gene cloning experiments revealed OmpK36 134-135GD-insertion and increased carbapenemase gene (blaNDM-1 and blaOXA-48-like) ...[more]

PMID: 38426743

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