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Published on: March 3, 2023

Antimicrobial susceptibility of non-enterococcal intrinsic glycopeptide-resistant Gram-positive organisms

Carlos Vay1, Roxana Cittadini, Claudia Barberis

  • 1Departamento de Bioquímica Clínica, Facultad de Farmacia y Bioquímica, Hospital de Clínicas, Universidad de Buenos Aires, Argentina, CP 1407, Buenos Aires, Argentina.

Diagnostic Microbiology and Infectious Disease
|October 20, 2006
PubMed

Insights

Intrinsically vancomycin-resistant, non-enterococcal Gram-positive bacteria are increasingly linked to serious infections. This study evaluated antimicrobial susceptibility for these emerging pathogens, finding erythromycin most effective overall.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Non-enterococcal Gram-positive bacteria intrinsically resistant to vancomycin are emerging pathogens.
  • Documented infections caused by these bacteria are increasing in frequency.
  • Understanding their antimicrobial susceptibility is crucial for effective treatment.

Purpose of the Study:

  • To determine the in vitro antimicrobial susceptibility of clinically relevant, intrinsically vancomycin-resistant, non-enterococcal Gram-positive bacteria.
  • To identify potential therapeutic agents for infections caused by these organisms.

Main Methods:

  • Minimum Inhibitory Concentrations (MICs) were determined for 19 antimicrobial agents using the agar dilution method.
  • Testing was performed on 28 bacterial strains isolated from clinical specimens between 1997 and 2003.
  • Bacterial species included Lactobacillus, Weissella, Leuconostoc, and Pediococcus.

Main Results:

  • Penicillin showed limited activity, with high MICs observed for most Leuconostoc and Pediococcus strains.
  • Erythromycin demonstrated the broadest activity against the tested strains.
  • Multidrug resistance was identified in two strains: Lactobacillus rhamnosus and Lactobacillus plantarum.

Conclusions:

  • Erythromycin is a promising agent for treating infections caused by these intrinsically vancomycin-resistant bacteria.
  • The emergence of multidrug resistance highlights the need for ongoing surveillance and susceptibility testing.
  • These bacteria should be considered potential pathogens in clinical settings.

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