Risk factors for development of vancomycin-resistant enterococcal bacteremia among VRE colonizers A retrospective case control study

Aims We aimed to determine the proportion of vancomycin-resistant enterococci (VRE) colonized patients among all inpatients who later developed VRE bacteremia during hospital stay and to identify the risk factors for VRE bacteremia at a tertiary hospital. Material and methods Patients with positive rectal screening or any clinically significant positive culture results for VRE were included in 1-year follow-up. Colonization with VRE was defined as a positive culture (rectal, stool, urinary) for VRE without infection and VRE bacteremia was defined as positive blood culture if the signs and symptoms were compatible with infection. To determine the risk factors for VRE bacteremia among VRE colonized patients, a retrospective case control study was performed. The two groups were compared in terms of variables previously defined as risk factors in the literature. Results Of 947 positive samples, 17 VRE bacteremia were included in the analysis. Cephalosporin use for more than 3 days within 3 months was a significant risk factor for bacteremia (p= 0.008). Prior use of carbapenems was found to be statistically significant for bacteremia (p= 0.007). In multivariate analyses the use of carbapenems and cephalosporins was an independent risk factor for developing bacteremia among VRE colonizers (odds ratio, OR, 6.67; 95% confidence interval, CI, 1.30-34;p= 0.022 and OR 4.32, 95% CI 1.23-15;p= 0.022,respectively). Conclusion A VRE colonization in patients receiving broad-spectrum beta-lactam antibiotics including carbapenems and cephalosporins may result in bacteremia. It is possible to keep mortality at very low levels in VRE bacteremia with effective infection control measures, rapid infectious diseases consultation and rational antimicrobial treatment based on current epidemiological data.