Antimicrobial Resistant CC17 Enterococcus faecium: The Past, the Present and the Future.

Enterococcus faecium are robust opportunistic pathogens that are most commonly found as commensals of the human and animal gut but can also survive in the environment. Since the introduction and use of antimicrobials, E. faecium have been found to rapidly acquire resistance genes which when expressed can effectively circumvent the effects of most antimicrobials. The rapid acquisition of multiple antimicrobial resistances has led to the adaptation of specific E. faecium clones in the hospital environment collectively known as clonal complex (CC)17. CC17 E. faecium are responsible for a significant portion of hospital-associated infections, which can cause severe morbidity and mortality. Here, we review the history of E. faecium from commensal to a significant hospital-associated pathogen, its robust phenotypic characteristics, commonly used laboratory typing schemes and antimicrobial resistances with a focus on vancomycin and its associated mechanism of resistance. Finally, we review the global epidemiology of vancomycin resistant E. faecium and potential solutions to problems faced in public health.