Emergence of Vancomycin-Variable Enterococci in Urinary Tract Infections in North India: A Cross-Sectional Molecular Study

Vancomycin-resistant enterococci (VRE) and Vancomycin-variable enterococci (VVE) pose significant challenges in urinary tract infections (UTIs) due to limited treatment options and silent resistance genes. To determine the prevalence, resistance profiles, and clinical outcomes of VRE and VVE in UTIs at a Regional AMR Surveillance Centre in North India. A cross-sectional study was conducted among hospitalized UTI patients (≥18 years) at a tertiary care hospital. Enterococcus isolates were identified by MALDI-TOF MS and tested for antimicrobial susceptibility (CLSI 2023). PCR was used to detect vanA, vanB, and vanC genes. All vanA -positive but phenotypically susceptible isolates were subjected to reversion assays on vancomycin-supplemented agar to confirm VVE status. Clinical data were analyzed for risk factors and outcomes. Of 130 Enterococcus isolates, 88.5% were E. faecalis and 11.5% E. faecium . VRE prevalence was 16.2% (21/130), with 90.5% harboring vanA . VVE comprised 8.5% (11/130). All 11 vanA -positive but phenotypically susceptible isolates reverted to resistance on vancomycin-supplemented agar, confirming true VVE. VRE showed 100% resistance to ampicillin, with high resistance to nitrofurantoin (85.7%), while VVE exhibited 63.6% ampicillin resistance and 9.1% nitrofurantoin resistance. Both groups retained 100% susceptibility to linezolid and fosfomycin. Clinical risk factors associated with VRE/VVE included urinary catheterization, ICU admission, and prolonged hospitalization (>30 days). Mortality was higher in VRE (25%) and VVE (18.2%) compared to VSE (6.3%) (p=0.023). This study confirms the presence of VVE in India by demonstrating reversion of all vanA -positive, vancomycin-susceptible isolates to resistant phenotypes. The high prevalence of VRE/VVE, driven by vanA , highlights the inadequacy of phenotypic AST alone. Targeted molecular screening of high-risk isolates may be considered to prevent therapeutic failure. Linezolid and fosfomycin remain effective options, but urgent strengthening of stewardship and infection control measures is warranted.