Exogenous hydrogen sulphide sensitizes carbapenemase-producing Acinetobacter baumannii to gentamicin

  • J Glob Antimicrob Resist. 2025 Jun:43:198-202. doi: 10.1016/j.jgar.2025.04.018.
Nicolas Helsens  1 ,  Jacqueline Findlay  2 ,  Maxime Bouvier  3 ,  Patrice Nordmann  4
Affiliations
  • 1. Clinical Microbiology Unit, Pasteur Institute of Lille, Lille, France; European Institute for Emerging Antibiotic Resistance, University of Fribourg, Fribourg, Switzerland.
  • 2. Department of Medicine, Medical and Molecular Microbiology, University of Fribourg, Fribourg, Switzerland.
  • 3. Department of Medicine, Medical and Molecular Microbiology, University of Fribourg, Fribourg, Switzerland; Swiss National Reference Center for Emerging Antibiotic Resistance, Fribourg, Switzerland.
  • 4. European Institute for Emerging Antibiotic Resistance, University of Fribourg, Fribourg, Switzerland; Department of Medicine, Medical and Molecular Microbiology, University of Fribourg, Fribourg, Switzerland; Swiss National Reference Center for Emerging Antibiotic Resistance, Fribourg, Switzerland. Electronic address: [email protected].
PMID: 40294863 DOI: 10.1016/j.jgar.2025.04.018
Abstract

Objective: Carbapenem-resistant Acinetobacter baumannii pose a major public health threat. These bacteria often display broad-spectrum Antibiotic resistance, rendering them resistant to nearly all classes of Antibiotics. Hydrogen sulphide (H2S), a compound naturally produced by many Bacterial species, has been proposed to exert a protective effect against certain Antibiotics. However, A. baumannii does not produced H2S.

Methods: To investigate the effect of exogenous H2S on Antibiotic resistance, several clinical isolates of carbapenemase-producing A. baumannii were cultured under various conditions, including the presence or absence of H2S and/or sub-inhibitory concentrations of gentamicin, azithromycin, ciprofloxacin, Tetracycline, and meropenem. Bacterial growth was assessed at multiple time points to evaluate growth dynamics.

Results: Exogenous H2S alone had a limited impact on Bacterial growth. However, its addition reduced the minimum inhibitory concentration of gentamicin and sensitized the bacteria to sub-inhibitory concentrations of this Antibiotic.

Conclusions: This study highlights the potential of H2S as an Antibiotic potentiator, suggesting that the use of this combination may be a promising strategy for treating pulmonary infections caused by A. baumannii or for preventing colonization on medical devices such as catheters.

Keywords
A. baumannii; Antibiotic resistance; Gentamicin; Hydrogen sulphide.
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