Eradication of Vancomycin-Resistant Enterococci by Combining Phage and Vancomycin

Area of Science:

• Microbiology
• Bacteriology
• Antimicrobial Resistance

Background:

• Vancomycin-resistant Enterococcus faecalis (VRE) poses a significant threat due to limited effective treatment options.
• The emergence of multidrug-resistant pathogens necessitates novel therapeutic strategies.

Purpose of the Study:

• To evaluate the synergistic efficacy of combining vancomycin with phage therapy against VRE.
• To assess the impact of this combined treatment on VRE planktonic and biofilm cultures.

Main Methods:

• Synergistic activity of vancomycin and anti-E. faecalis phage EFLK1 was tested against VRE.
• Biofilm biomass and viable counts were quantified; scanning electron microscopy (SEM) was used for visualization.
• Changes in bacterial cell wall peptidoglycan were analyzed using confocal microscopy and fluorescence-activated cell sorting (FACS).

Main Results:

• The combination of vancomycin and phage demonstrated synergistic efficacy against both planktonic and biofilm VRE cultures.
• Phage treatment led to an eight-fold increase in fluorescence intensity, indicating alterations in the cell wall peptidoglycan.
• Combined treatment rendered VRE strains no more problematic than vancomycin-susceptible strains.

Conclusions:

• Combined vancomycin and phage therapy is a highly effective strategy against VRE.
• This approach offers a promising solution in the ongoing battle against multidrug-resistant bacteria.
• The observed changes in peptidoglycan suggest a mechanism for enhanced antimicrobial activity.