Molecular profiling of vancomycin-resistant enterococci isolated from bloodstream infections by enterobacterial repetitive intergenic consensus-polymerase chain reaction: A prospective cross-sectional study from Northeast India.

Purpose: Enterococcus spp. Has emerged as a significant cause of bacteremia, often leading to severe complications such as Infective Endocarditis. The rise of Vancomycin-Resistant Enterococci (VRE) poses a critical challenge in treating Enterococcal bacteremia, particularly in hospital settings. This study aims to conduct molecular characterization and genotyping of VRE strains isolated from blood samples in a tertiary care hospital.

Methods: This hospital-based prospective cross-sectional study was conducted at a tertiary care hospital in Tripura, Northeast India, from August 2021 to December 2024. Blood samples from both adult and pediatric patients were collected and processed for culture and organism identification following departmental protocols. Antimicrobial susceptibility of isolated Enterococcus spp. Was assessed, and vancomycin resistance confirmed through VRE screening. Real-time PCR was employed for VRE gene detection, and ERIC-PCR was used for genotyping the VRE strains.

Results: During the study, 626 blood samples were analyzed, with 263 (42 %) testing positive for pathogens. Enterococcus spp. Was the third most common isolate (21.7 %), predominantly E. faecalis (63.2 %). Most cases originated from ICU (52.6 %) and the Medicine Department (49.1 %). Linezolid showed 100 % sensitivity, while Vancomycin had 75.4 % sensitivity. Ciprofloxacin exhibited the highest resistance (44 % sensitivity). VRE was detected in 14 strains (24.6 %), all carrying the VanA gene. ERIC-PCR identified three clusters, with most isolates (n=11) in Cluster III, including the ATCC control strain.

Conclusion: This study highlighted the prevalence, resistance patterns, and molecular characteristics of Enterococcus spp. Causing bloodstream infections in a Northeast Indian state. The predominance of VanA-mediated resistance and its clustering in critical care settings call for immediate attention to infection control and targeted antimicrobial strategies. Future research should focus on the environmental and epidemiological factors contributing to the spread of VRE in hospital as well as community settings in the region.