title: The rise of the Enterococcus: beyond vancomycin resistance.
abstract: The genus Enterococcus includes some of the most important nosocomial multidrug-resistant organisms, and these pathogens usually affect patients who are debilitated by other, concurrent illnesses and undergoing prolonged hospitalization. This Review discusses the factors involved in the changing epidemiology of enterococcal infections, with an emphasis on Enterococcus faecium as an emergent and challenging nosocomial problem. The effects of antibiotics on the gut microbiota and on colonization with vancomycin-resistant enterococci are highlighted, including how enterococci benefit from the antibiotic-mediated eradication of gram-negative members of the gut microbiota. Analyses of enterococcal genomes indicate that there are certain genetic lineages, including an E. faecium clade of ancient origin, with the ability to succeed in the hospital environment, and the possible virulence determinants that are found in these genetic lineages are discussed. Finally, we review the most important mechanisms of resistance to the antibiotics that are used to treat vancomycin-resistant enterococci.
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, Center for the Study of Emerging and Re-emerging Pathogens, Houston, Texas 77030, USA. cesar.arias@uth.tmc.edu
authors.forename: Cesar A
authors.initials: CA
authors.lastname: Arias
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Murray
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004751:Enteritis / Q000453:epidemiology / Q000382:microbiology; D016984:Enterococcus faecium / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity*; D041981:Gastrointestinal Tract / Q000382:microbiology; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D006801:Humans; D056265:Microbial Interactions; D014640:Vancomycin / Q000494:pharmacology; D020713:Vancomycin Resistance / Q000235:genetics / Q000502:physiology*; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D037521:Virulence Factors; D014640:Vancomycin