Version 1: Emerging trend of Vancomycin Resistant Enterococcal Bacteremia in a university hospital in Northern India – An observational analysis

Introduction: Vancomycin Resistant Enterococcus (VRE) species has been increasing and is now of serious concern. timely analysis of VRE bacteremia must be done in every institution to find the pattern of VRE prevalence.

Aim: To find the prevalence of VRE bacteremia at our institution. Also, the demographic pattern, associated risk factors, sensitivity pattern and outcomes associated with bacteremia caused by VRE were also estimated.

Methods: This observational study was done in the Microbiology department of our institute from April 2022 to June 2023. All patients with blood cultures positive for Enterococcus species for the first time during the study period were included in the study. The Blood culture bottles were loaded in the BACT/ALERT system. Once the bottle flagged a positive signal, culture was done and Gram staining was done. Identification was done using MALDI-Tof MS. Antimicrobial Sensitivity Testing was done by Kirby Bauer disk diffusion method and interpreted using Clinical and Laboratory Standards Institute (CLSI) 2023 M-100 clinical breakpoints. The demographic details, risk factors, and the clinical outcome of the patients included in the study were collected and analyzed.

Results: During the study period, 29086 blood culture bottles were received. Of these, 2016 (6.93%) bottles flagged positive. Enterococcus species were isolated from 256 (12.69%) blood cultures. Of the 256 Enterococcus isolates, 45 (17.57%) isolates were Vancomycin Resistant Enterococcus (VRE). The most common species isolated were Enterococcus faecium (n=42; 93.33%), followed by Enterococcus faecalis (n=2; 4.44%) and Enterococcus gallinarum (n=1; 2.22%). Most of the patients belonged to the age group 41-60 years (n=14; 31.11%). Male:Female ratio was 1.25:1. Diabetes mellitus and neutropenia were found to be significant risk factors among patients with VRE bacteremia. All the isolates showed 100% resistance to Teicoplanin, Ampicillin, Ampicillin-sulbactam and Levofloxacin. In 29 (64.44%) patients, bacteremia was the cause of death. On univariate analysis, mortality was found to be significantly higher in patients with Vancomycin Resistant Enterococcal (VRE) bacteremia as compared to patients with Vancomycin Sensitive Enterococcal (VSE) bacteremia.

Conclusion: An increasing prevalence of VRE bacteremia was observed in the study. Proper implementation of antimicrobial stewardship rules in the hospital is the best way to overcome the increasing trend of resistance.