Abstract
Enterococcus faecium is difficult to treat owing to its intrinsic and acquired resistance to antibiotics, particularly vancomycin. Vancomycin-resistant Enterococcus faecium is an important cause of bloodstream infections in healthcare settings with limited treatment options. This study aimed to analyze the risk factors for vancomycin-resistant Enterococcus faecium bloodstream infection. This retrospective analysis of data from the Munich Multicentric Enterococci Cohort analyzed 200 episodes of nonrecurrent vancomycin-susceptible Enterococcus faecium bloodstream infection and 196 episodes of nonrecurrent vancomycin-resistant Enterococcus faecium bloodstream infection from six hospitals in Munich, Germany, between 2010 and 2019. Logistic regression was used to identify risk factors for vancomycin-resistant Enterococcus faecium bloodstream infection. In the unadjusted analysis, the risk factors for vancomycin-resistant Enterococcus faecium bloodstream infection included the length of hospital stay, previous treatment with vancomycin or linezolid, and solid organ transplantation. In the multivariable analysis, prior treatment with vancomycin and solid organ transplantation were independent risk factors for vancomycin-resistant Enterococcus faecium bloodstream infection. Vancomycin resistance was not significantly associated with the severity of underlying diseases. This study identified prior vancomycin treatment and solid organ transplantation as key independent risk factors for vancomycin-resistant Enterococcus faecium bloodstream infection. IMPORTANCE: Vancomycin-resistant Enterococcus faecium is a growing threat in healthcare settings, challenging the management of enterococcal infections. This study identified prior treatment with vancomycin and solid organ transplantation as risk factors for vancomycin-resistant Enterococcus faecium bloodstream infections. Based on the analysis of five disease severity scores for acute and chronic illness, the severity of underlying diseases could not be demonstrated to be a risk factor for the occurrence of vancomycin resistance in Enterococcus faecium bloodstream infections.