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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
Linezolid-resistant enterococci in Greece: epidemiological characteristics
Iris Spiliopoulou1, Anthi Damani, Vassiliki Chini
1Department of Microbiology, School of Medicine, University of Patras, Greece.
Chemotherapy
|April 9, 2011
Summary
Common linezolid-resistant enterococci strains, including Enterococcus faecium and Enterococcus faecalis, were identified in Greek intensive care units. These resistant strains carried a specific mutation and belonged to known international epidemic clones, highlighting infection control needs.
Area of Science:
- Microbiology
- Infectious Diseases
- Molecular Epidemiology
Background:
- Investigated 14 linezolid-resistant enterococci isolates (6 Enterococcus faecium, 8 Enterococcus faecalis) from Greek intensive care units (ICUs) in 2009.
- Focused on understanding the prevalence and characteristics of these resistant strains in a hospital setting.
Purpose of the Study:
- To determine the genetic mechanisms conferring linezolid resistance in enterococci.
- To identify the clonal types of linezolid-resistant enterococci circulating in Greek ICUs.
- To assess the epidemiological relatedness of these resistant strains.
Main Methods:
- Sequencing analysis of the domain V of 23S ribosomal DNA (rDNA) to identify resistance mechanisms.
- Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) to define clonal relatedness.
Main Results:
- All investigated linezolid-resistant enterococci isolates harbored the G2576T mutation in the 23S rDNA.
- Enterococcus faecium strains belonged to international epidemic clones ST16, ST17, ST203, and ST65.
- All Enterococcus faecalis strains were identified as belonging to the ST28 clone.
Conclusions:
- The findings indicate the circulation of common, internationally recognized linezolid-resistant enterococcal clones within Greek ICUs.
- The presence of these specific clones underscores the need for robust infection control strategies.
- Implementing effective infection control measures is crucial to prevent the dissemination of these resistant strains in healthcare settings.
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