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. 2025 Feb;74(2):001955.
doi: 10.1099/jmm.0.001955.

Preserving the antimicrobial arsenal: exploring alternatives to carbapenems in ESBL battles within the southeast of Ireland

Saied Ali  1   2 , Aideen Tobin  1 , Susan Lapthorne  1 , Meadhbh Collison  1 , Doireann Murphy  1 , Grace Chan  1 , Maeve Doyle  1
Affiliations

Preserving the antimicrobial arsenal: exploring alternatives to carbapenems in ESBL battles within the southeast of Ireland

Saied Ali et al. J Med Microbiol. 2025 Feb.

Abstract

Introduction. Carbapenems are usually employed as first-line antimicrobials against bacteria harbouring extended-spectrum beta-lactamases (ESBLs). These enzymes confer resistance often to multiple classes of antimicrobials.Hypothesis/Gap Statement. This indiscriminate use of carbapenems and the inevitable development of carbapenem resistance have prompted the need for carbapenem-sparing strategies.Methodology. The non-carbapenem antimicrobial susceptibility patterns of 60 ESBL-producing Enterobacterales (ESBL-PE) isolates responsible for bloodstream infections, in 2022-2023 inclusive, processed at our institution were reviewed.Results. The non-carbapenem antimicrobial susceptibility patterns of 60 ESBL-PE isolates from bloodstream infections during the study period were determined. Escherichia coli was the most common species isolated (87%, n=52), with the majority of cases (73.3%, n=44) originating from a presumed urinary source. Temocillin (TMC), mecillinam (MEC), cefiderocol (FDC), amikacin and fosfomycin (FOS) displayed excellent activity against all ESBL-PE isolates tested, with susceptibility rates of≥85%. Ciprofloxacin and amoxicillin-clavulanic acid were the least efficacious agents, with susceptibility rates≤20%.Conclusions. TMC, MEC, FDC and FOS offer promising alternatives to carbapenems, demonstrating efficacy against ESBL-PE. The use of these agents not only broadens the therapeutic arsenal against ESBL-PE but also mitigates the potential for escalating carbapenem resistance, especially in regions where the incidence of carbapenem resistance is increasing.

Keywords: ESBL; Enterobacterales; antimicrobial resistance; antimicrobial stewardship; antimicrobials; carbapenems; extended-spectrum beta-lactamase; surveillance.

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Conflict of interest statement

The authors declare that there are no conflicts of interest.

Figures

Fig. 1.
Fig. 1.. Species of Enterobacterales reviewed.
Fig. 2.
Fig. 2.. Percentage of susceptible isolates among all isolates to antimicrobials tested. All susceptibility results were interpreted according to EUCAST breakpoints. In cases where specific breakpoints are not well-defined, such as for certain bacterial species or sources of infection, susceptibility was interpreted based on Enterobacterales breakpoints, disregarding species-specific and source-specific restrictions.
Fig. 3.
Fig. 3.. Percentage of susceptible isolates to antimicrobials tested with EUCAST caveats applied.
See this image and copyright information in PMC

References

    1. Husna A, Rahman MM, Badruzzaman ATM, Sikder MH, Islam MR, et al. Extended-Spectrum β-Lactamases (ESBL): challenges and opportunities. Biomedicines. 2023;11:2937. doi: 10.3390/biomedicines11112937. - DOI - PMC - PubMed
    1. Castanheira M, Simner PJ, Bradford PA. Extended-spectrum β-lactamases: an update on their characteristics, epidemiology and detection. JAC Antimicrob Resist . 2021;3:dlab092. doi: 10.1093/jacamr/dlab092. - DOI - PMC - PubMed
    1. Lagacé-Wiens PR, Nichol KA, Nicolle LE, Decorby MR, McCracken M, et al. ESBL genotypes in fluoroquinolone-resistant and fluoroquinolone-susceptible ESBL-producing Escherichia coli urinary isolates in Manitoba. Can J Infect Dis Med Microbiol. 2007;18:133–137. doi: 10.1155/2007/848194. - DOI - PMC - PubMed
    1. Doi Y, Wachino J, Arakawa Y. Aminoglycoside resistance. Infect Dis Clin North Am. 2016;30:523–537. doi: 10.1016/j.idc.2016.02.011. - DOI - PMC - PubMed
    1. Karaiskos I, Giamarellou H. Carbapenem-Sparing Strategies for ESBL Producers: When and how. Antibiotics. 2020;9:61. doi: 10.3390/antibiotics9020061. - DOI - PMC - PubMed

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