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Published on: April 18, 2019
Combating antimicrobial resistance in ESBL- and AmpC-producing Enterobacterales: In vitro evaluation of
Pooja Haleangadi1, M Suchitra Shenoy1, Anisha Maria Fernandes1
1Department of Microbiology, Kasturba Medical College Mangalore, Manipal Academy of Higher Education, Manipal, India.
Purpose:
To evaluate the in-vitro activity of cefepime-enmetazobactam (FEP-EMT)-a novel β-lactam-β-lactamase inhibitor (BL/BLI) combination against Extended-spectrum β-lactamase (ESBL)- and AmpC β-lactamase (AmpC)- producing Enterobacterales isolated from diverse clinical samples. To compare efficacy of FEP-EMT against other BL/BLIs and assess its use as a potential carbapenem sparing option.
Methods:
A prospective laboratory study was conducted and 147 clinically significant nonrepetitive ESBL- and/or AmpC-producing Enterobacterales isolated from various clinical samples were included. The zone diameter for FEP-EMT was determined by Kirby-Bauer disk diffusion method and interpreted according to the EUCAST July 2024 guidelines. The susceptibility to other antibiotics, was noted as per CLSI 2025, with special emphasis to BL/BLIs.
Results:
Between January 2025 and September 2025, 147 ESBL- and/or AmpC-producing isolates were collected from clinically relevant specimens. Escherichia coli (106, 72.1%) was the most predominant isolate, followed by Klebsiella pneumoniae (32, 21.8%). Among the 147 isolates, 95.2% were susceptible to FEP-EMT compared to 88.7%, 73.4% and 63.0% susceptibility to cefaperazone-sulbactam, piperacillin-tazobactam and amoxicillin-clavulanic acid respectively. Notably, all FEP-EMT (7/147) resistant isolates demonstrated resistance to these BL/BLI combinations. FEP-EMT restored susceptibility to cefepime in 97.8% isolates. FEP-EMT demonstrated good activity in Enterobacterales demonstrating multiple resistance mechanisms to third generation cephalosporins.
Conclusion:
Cefepime-enmetazobactam showed higher or comparable in vitro activity against ESBL- and/or AmpC-producing Enterobacterales compared to conventional BL/BLI options. Hence, it can serve as an effective alternative treatment for resistant pathogens.
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