title: Virulence markers of vancomycin resistant enterococci isolated from infected and colonized patients.
abstract: BACKGROUND
  The aim of study was to find out the potential pathogenic role of virulence factors elaborated by strains of vancomycin resistant enterococci (VRE) isolated from clinical samples and VRE colonizing the gastrointestinal tract of hospitalized patients.
  
  
  METHODS
  Enterococci were isolated from various clinical samples and also from fecal specimens of colonized patients at the time of admission, after 48 h and after 5 days of admission. Various virulence determinants were detected by phenotypic tests. Vancomycin susceptibility in enterococci was detected by disc diffusion and agar screen method. Minimum inhibitory concentration was determined by agar dilution method.
  
  
  RESULTS
  Out of all the clinical and fecal samples processed, 12.0% isolates were either vancomycin resistant or vancomycin intermediate. Hemagglutinating activity against rabbit red blood cells was seen with 27.8% and 25.0% of clinical and fecal strains, respectively. Slime layer formation was seen with fecal VRE strains (37.5%) when compared to clinical VRE (27.8%). Among the clinical VRE strains the most prolific biofilm producers were Enterococcus. fecalis (92.9%) when compared to Enterococcus. faecium (52.9%). Biofilm formation/(presence of adhesions) was also seen in (29.2%) of the fecal VREs. In wound infection production of gelatinase, deoxyribonuclease (DNase), and caseinase (70.0% each) were the major virulence factors. The predominant virulence factors seen in the blood stream infection were adhesin, and hemolysin (44.4% each) and in catheter induced infection were DNase and adhesins (75.0% each). Adhesin (29.2%), slime layer (37.6%), DNAse (33.3%), gelatinase (25.0%), lipase (20.8%) and caseinase (16.6%) and hemolysin (8.3%) were produced the fecal isolates.
  
  
  CONCLUSIONS
  An association between adhesin (as detected by biofilm formation) and urinary tract infection, adhesion and hemolysin with BSI, as also between DNase gelatinase & caseinase with wound infection was noted.
authors.affiliation: Department of Microbiology, Katihar Medical College, Katihar, Bihar, India.
authors.forename: Priyanka Paul
authors.initials: PP
authors.lastname: Biswas
authors.affiliation: Department of Microbiology, Katihar Medical College, Katihar, Bihar, India.
authors.forename: Sangeeta
authors.initials: S
authors.lastname: Dey
authors.affiliation: Sikkim Manipal University, Gangtok, Sikkim, India.
authors.forename: Luna
authors.initials: L
authors.lastname: Adhikari
authors.affiliation: Department of Microbiology, Katihar Medical College, Katihar, Bihar, India.
authors.forename: Aninda
authors.initials: A
authors.lastname: Sen
keywords: Blood stream infection; Catheter induced infection; Urinary tract infection; Vancomycin intermediate enterococci; Vancomycin resistant enterococci