[Analysis of Antimicrobial Resistance Trends and Characteristics of Vancomycin-resistant Enterococcus faecium Isolated in the Republic of Korea from 2018 to 2023].

Vancomycin-resistant enterococci (VRE) are a leading cause of healthcare-associated infections, with limited options for antimicrobial treatment. Resistance genes and their pathogenicity can be transmitted via transposons, making infection control crucial. In this study, we analyzed the antibiotic resistance trends and pathogenic characteristics of 179 Enterococcus faecium strains, which accounted for 78.5% of the 228 VRE strains collected from the epidemic intelligence division integrated system between 2018 and 2023. The analysis revealed that all strains were resistant to vancomycin, levofloxacin, and ciprofloxacin, but susceptible to linezolid and chloramphenicol. All 179 strains possessed the vanA gene. Among these, 55 strains (30.7%) exhibited the VanB phenotype and showed intermediate resistance or susceptibility to teicoplanin. As a result of virulence factor analysis, 155 strains (86.6%) were confirmed to possess both esp and hyl genes. Multilocus sequence typing analysis revealed ST17 (48.1%) and ST192 (11.1%) as the predominant sequence types, consistent with the global distribution patterns of vancomycin-resistant E. faecium (VREfm). This study provides critical insights into the antibiotic resistance trends and genetic characteristics of VREfm in the Republic of Korea, offering a foundation for antibiotic resistance prevention and infection control efforts.