First description in Europe of the emergence of Enterococcus faecium ST117 carrying both vanA and vanB genes, isolated in Greece

• Published in: Journal of global antimicrobial resistance. Vol. 11; pp. 68 - 70
• Main Authors: Papagiannitsis, C.C., Malli, E., Florou, Z., Medvecky, M., Sarrou, S., Hrabak, J., Petinaki, E.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01-12-2017
• Subjects: Anti-Bacterial Agents - pharmacology; Bacteremia - microbiology; Bacterial Proteins - genetics; Carbon-Oxygen Ligases - genetics; DNA Transposable Elements; Electrophoresis, Gel, Pulsed-Field; Enterococcus faecium; Enterococcus faecium - drug effects; Enterococcus faecium - genetics; Enterococcus faecium - isolation & purification; Enterococcus faecium - pathogenicity; Europe; Gene Expression Regulation, Bacterial; Genes, Bacterial - genetics; Genotype; Gram-Positive Bacterial Infections - microbiology; Greece - epidemiology; Hospitals; Humans; Microbial Sensitivity Tests; Molecular Epidemiology; Multilocus Sequence Typing; Phenotype; Plasmids - genetics; Protein Kinases - genetics; ST117; Teicoplanin - pharmacology; Transcription Factors - genetics; vanA; vanB; Vancomycin - pharmacology; Vancomycin Resistance; Vancomycin-Resistant Enterococci - genetics; Greece; Europe; vanB; Enterococcus faecium; vanA; ST117
• ISSN: 2213-7165; 2213-7173
• DOI: 10.1016/j.jgar.2017.07.010

•First report in Europe (Greece) of a ST117 Enterococcus faecium carrying both vanA and vanB genes.•vanA was carried on a plasmid exhibiting high similarity to pA6981 previously characterised from E. gallinarum A6981.•vanB was part of a Tn1549-like transposon integrated into the chromosome.•Full resistance to vancomycin and teicoplanin (MICs=256mg/L correlated with the presence of intact vanZ and vanS genes).
An Enterococcus faecium isolate (Efa-125) carrying both the vanA and vanB genes was recovered from a patient with bacteraemia treated in a Greek hospital. Since this is the first description in Europe of E. faecium carrying both vanA and vanB genes, the isolate was further studied.
Susceptibility to several antibiotics was determined using the VITEK®2 automated system. The isolate was typed by multilocus sequence typing (MLST). To define the genetic units of the vanA and vanB genes, the plasmid content of Efa-125 was analysed by pulsed-field gel electrophoresis (PFGE) of total DNA digested with S1 nuclease followed by hybridisation with digoxigenin-labelled vanA and vanB probes. In addition, plasmids and chromosomes were sequenced using the Illumina MiSeq platform.
E. faecium Efa-125 belonged to ST117 and expressed resistance both to vancomycin and teicoplanin, with minimum inhibitory concentrations (MICs) for both of 256mg/L. The vanA gene was carried on a 29 320-bp plasmid exhibiting high similarity to pA6981 previously characterised from Enterococcus gallinarum A6981, whereas vanB was part of a Tn1549-like transposon integrated into the chromosome. Expression of the VanA phenotype was correlated with the presence of intact vanZ and vanS genes.
This is the first detection in Greece of vanA–vanB genotype/VanA phenotype E. faecium and indicates an evolving epidemiology of vancomycin-resistant enterococci.