Abstract:
Enterococci have become major nosocomial pathogens. An increasing number of these
infections are as a result of vancomycin-resistant enterococci. Accurate detection of vancomycinresistant
enterococci (VRE) is important, so that appropriate therapy and infection control measures
may be instituted, including veterinary surveillance. Two screening assays to detect vancomycin
resistance in enterococci are proposed. Barnes Basal Medium agar (Ba) and Brain Heart Infusion (BHI)
broth (plus 1% TTC-2,3,5-triphenyltetrazolium chloride) with several concentrations of vancomycin
were used in this work. Five Enterococcus casseliflavus strains with low-level resistance to vancomycin
(4 g/mL) were used. Both media were able to quickly detect the breakpoint of the vancomycinresistant
strains used in this work, and also provided insight into the dynamics of the antibiotic effect
at a low concentration on the tested bacterial suspensions.
