Background: 14 linezolid-resistant enterococci (6 Enterococcus faecium and 8 Enterococcus faecalis) collected during 2009 from patients hospitalized in intensive care units of different Greek hospitals were investigated. Methods: The mechanism of resistance to linezolid was determined by sequencing analysis of the domain V of 23S rDNA, while the clonal relatedness was defined by pulsed-field gel electrophoresis and multilocus sequence typing. Results: All linezolid-resistant enterococci carried the G2576T mutation. E. faecium belonged to the international epidemic clones ST16, ST17, ST203 and ST65, while all E. faecalis strains belonged to the ST28 clone. Conclusions: The spread of common linezolid-resistant enterococcal clones in intensive care units located in different areas of Greece emphasizes the importance of application of infection control measures to prevent the spread of such strains.

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