LABORATORY APPROACHES TO DETECT VANCOMYCIN-RESISTANT AND VANCOMYCIN-VARIABLE ENTEROCOCCI: CURRENT PERSPECTIVES

Authors: SivaSakthi Srikanth, Valentina Yogamoorthi, Vinoj Gopalakrishnan, Joshy M Easow

DOI: 10.18231/j.ijmmtd.12298.1761390851

Keywords: vancomycin-resistant enterococci, vancomycin-variable enterococci, Phenotypic methods, Genotypic methods

Abstract: The global spread of vancomycin-resistant enterococci (VRE), particularly Enterococcus faecium and Enterococcus faecalis, poses a substantial healthcare risk due to limited treatment options and a high potential for nosocomial transmission. Adding to this challenge is the development of vancomycin-variable enterococci (VVE), containing van A or van B genes but appearing susceptible in routine phenotypic tests, leading to diagnostic uncertainty, potential treatment failure, and silent spread. This review critically evaluates current laboratory methods for detecting VRE and VVE, including phenotypic assay, automated systems, and advanced molecular tools such as polymerase chain reaction (PCR). Loop-mediated isothermal amplification (LAMP), lateral flow assay, and whole genome sequencing. The limits of phenotypic approaches in recognising VVE are highlighted, as is the significance of molecular diagnostics in bridging these gaps. This review emphasises the importance of an integrated diagnostic approach to enhance detection accuracy, inform clinical management, and improve antimicrobial resistance surveillance.