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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
Summary
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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