Enterococci As Nosocomial Pathogen
Enterococcal species are Gram-positive lactic acid bacteria that are ubiquitously present in environmental samples, plants, and gastrointestinal tracts of animals. As commensals they are known to benefit the host, but in recent years, they have earned dubious reputation as nosocomial pathogens. They are known to cause diseases like urinary tract infections, endocarditis, bacteremia, and intra-abdominal infections especially in immunocompromised patients that are subjected to prolonged antibiotic treatments. The various factors contributing to their status as nosocomial pathogens are their intrinsic and acquired resistance to various classes of antibiotics. They are known to persist on animate and inanimate surfaces for a long period of time which thus act as reservoirs for the spread of the infection in hospitals. Recent studies have shown that the nosocomial strains are genetically distinct from commensal Enterococcal strains. Thus, herein the various diseases caused by nosocomial Enterococcus spp., the problem of antibiotic resistance, and their treatment have been reviewed. Further, this chapter also discusses the various virulence factors contributing to its pathogenicity and highlights the genetic differences between pathogenic and commensal Enterococcus spp.
KeywordsEnterococcus faecium E. faecalis Nosocomial Pathogen Virulence factors
This work was supported by research grant (grant number, 42-478/2013 SR) sponsored by the University Grants Commission (UGC), New Delhi, India. Ms. Preeti Sharma is thankful to the University of Potential for Excellence scheme of UGC for the fellowship. Ms. Sumanpreet Kaur is thankful to UGC for the fellowship.
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