The rapid emergence of high level gentamicin resistance in enterococci

K R Forward1, J K Kennedy, P A Degagne

  • 1Departments of Laboratory Medicine and Medicine, St Boniface General Hospital; and Departments of Medical Microbiology and Medicine, University of Manitoba, Winnipeg, Manitoba.

Insights

High-level gentamicin resistance in enterococci increased significantly from 1983 to 1986-87. This rapid rise in gentamicin resistance poses serious risks for patients with severe enterococcal infections.

Area of Science:

  • Clinical microbiology
  • Infectious diseases
  • Antimicrobial resistance

Background:

  • Enterococci are significant causes of nosocomial infections.
  • Gentamicin and streptomycin are commonly used antibiotics for enterococcal infections.
  • Monitoring antimicrobial resistance patterns is crucial for effective treatment.

Purpose of the Study:

  • To determine the proportion of enterococci with high-level resistance to gentamicin and streptomycin.
  • To track the emergence of gentamicin resistance in clinical isolates over time.

Main Methods:

  • Analysis of enterococci isolates from blood and urine cultures.
  • Determination of high-level resistance to gentamicin and streptomycin.

Main Results:

  • No high-level gentamicin resistance observed in 1983.
  • By 1986-87, 25% of blood and 17% of urine isolates showed high-level gentamicin resistance.
  • Emergence of resistance was observed for both gentamicin and streptomycin.

Conclusions:

  • A rapid increase in high-level gentamicin resistance among enterococci was documented.
  • This trend has critical implications for managing severe enterococcal infections.
  • Continued surveillance of antimicrobial resistance is essential.

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