Virulence factors in isolates of Enterococcus faecalis from infective endocarditis and from the normal flora.

Infective endocarditis (IE) is a severe infection associated with significant morbidity and mortality. Enterococcus faecalis is among the most common causes of this disease, and yet little is known about the pathogenesis of E. faecalis IE. We screened 21 E. faecalis isolates from IE and 21 isolates from normal flora for the putative virulence factors ace, asa1, gelE, and esp with PCR. In addition, we determined the ability of the isolates to form biofilm and to aggregate platelets. With the exception of biofilm formation, which was more pronounced in the normal flora group, there was no difference between the groups, indicating that many isolates have virulence properties and that host factors might determine if E. faecalis causes IE.