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High level resistance to aminoglycosides in enterococci from Riyadh

S R Al-Ballaa1, S M Qadri, S R Al-Ballaa

  • 1Departments of Medicine, Pathology and Microbiology, King Saud University, and Department of Pathology, Section of Clinical Microbiology, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia .

Annals of Saudi Medicine
|July 1, 1994
PubMed

Insights

High-level aminoglycoside resistance in enterococci is a growing global concern, leading to treatment failures. This study found significant resistance rates in Riyadh, Saudi Arabia, particularly for kanamycin and streptomycin.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Enterococci infections are increasingly difficult to treat due to high-level aminoglycoside resistance (HLAR).
  • HLAR compromises the synergistic effect of aminoglycosides with cell wall active agents, leading to treatment failures.

Purpose of the Study:

  • To determine the prevalence of enterococci with high-level aminoglycoside resistance (HLAR) in clinical isolates from Riyadh, Saudi Arabia.
  • To identify specific aminoglycoside resistance patterns and common enterococcal species exhibiting HLAR.

Main Methods:

  • Disk diffusion method was used to test 241 distinct clinical enterococcal isolates against high-content aminoglycoside disks.
  • Isolates were screened for resistance to gentamicin, tobramycin, kanamycin, and streptomycin.

Main Results:

  • Overall, 30% of isolates (74/241) exhibited resistance to at least one aminoglycoside.
  • High-level resistance was most common for kanamycin (27%) and streptomycin (22%).
  • Enterococcus faecium isolates showed a high rate (72%) of resistance to two or more aminoglycosides.

Conclusions:

  • A significant prevalence of high-level aminoglycoside resistance in enterococci was observed in Riyadh.
  • Kanamycin and streptomycin resistance were the most frequent patterns identified.
  • Enterococcus faecium represents a key species with high rates of multidrug resistance to aminoglycosides, posing a clinical challenge.

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