Detection of Vancomycin Resistance (van Genes) in Clinical Isolates of Enterococcus A review study

Abstract

Vancomycin-resistant enterococci (VRE), primarily Enterococcus faecium and E. faecalis, are high-priority healthcare related pathogens that cooperation empiric therapy, prolong hospitalization, and increase mortality. Resistance is most often facilitated by acquired van gene clusters—especially vanA and vanB—which remodel the peptidoglycan target from D-Ala–D-Ala to D-Ala–D-Lac (or D-Ala–D-Ser), reducing vancomycin binding. Mobile elements (e.g., Tn1546) and plasmids facilitate horizontal spread within and between lineages and species. Phenotypic detection uses consistent MIC methods (broth microdilution; careful use of automated systems) guided by CLSI, while molecular detection targets van operons by PCR or WGS. In India, surveillance advises data shows rising VRE proportions in tertiary centers with E. faecium predominance, reflecting global trends reported by CDC. Therapeutic options include linezolid and high-dose daptomycin (often with synergy), while infection-prevention and antimicrobial-stewardship remain basic controls.