Nosocomial infection with vancomycin-dependent enterococci

Area of Science:

• Infectious Diseases
• Microbiology
• Antimicrobial Resistance

Background:

• Vancomycin-resistant enterococci (VRE) are a significant nosocomial pathogen.
• The evolution of antimicrobial resistance, including vancomycin dependence, is a growing concern.
• Enterococcal infections pose challenges in healthcare settings.

Purpose of the Study:

• To report on patients infected with unique strains of vancomycin-dependent enterococci.
• To investigate the potential role of prolonged vancomycin exposure in the development of vancomycin dependence.
• To compare antimicrobial exposure in patients with vancomycin-dependent enterococci versus control groups.

Main Methods:

• Case series reporting on three patients with vancomycin-dependent enterococci.
• Comparison of antimicrobial exposure (vancomycin, third-generation cephalosporins) between cases and two control groups (VRE-infected and non-enterococcal infection patients).
• Genetic analysis of enterococcal strains.

Main Results:

• Three patients were infected with unique vancomycin-dependent enterococci strains.
• Two patients were initially infected with genetically identical vancomycin-resistant enterococci strains.
• Patients with vancomycin-dependent enterococci showed significantly greater exposure to vancomycin and third-generation cephalosporins compared to controls.

Conclusions:

• Antimicrobial pressure, particularly from vancomycin, may drive nosocomial colonization by VRE.
• Prolonged vancomycin exposure might facilitate the emergence of vancomycin dependence from vancomycin resistance.
• Understanding these evolutionary pathways is crucial for infection control and treatment strategies.