Vancomycin resistant enterococci colonization and infection risk factors

The aim of this retrospective case-control study is to evaluate risk factors of rectal colonization with vancomycin resistant enterococi and enterococcal bacteraemia. In our study we included patients in whom VRE was isolated from perirectal swab culture and followed up at the tertiary intensive care units (which has 85 adult bed capacity ) of our hospital. 108 patients who were colonized with VRE and 14 patients in whom VRE grew in blood cultures after colonization were evaluated for risk factors. Among the patients colonized with VRE ; Usage of antibiotics which included piperacillin tazobactam (p=0.007) , cefoperazone sulbactam (p=0.028) , carbapenems (p<0.001) , colistin (p=0.001), sulbactam (p=0.001), glycopeptides (p=0.001) were found to be significant risk factors. Invasive procedures which included endotracheal intubation (p=0.006), nasogastric catheterization (p=0.003), tracheostomy (p=0.024), hemodialysis (p=0.048), reintubation (p=0.008), central venous catheterization (p=0.001), were found to be significant. Immunosuppression (p=0.041) was found to be a significant risk factor from amongst the patients' concomitant conditions. Mean number of days of hospitalization was 24,65 ± 48,82 for patients colonized with VRE and 9,12±15,25 for patients who had negative VRE rectal swab cultures. Prolonged hospitalization (p=0.002) was found to be a significant risk factor for VRE colonization. Also APACHE-II score ≥ 20 was found to be statistically significant. Species of colonizing VRE were E. faecium in 82 (75.9%), E. faecalis in 6 (5.6%) and Enterococcus species in 20 (18.5%) patients. Among the patients with VRE bacteraemia; When we evaluated the risk factors; of the antibiotics, usage of vancomycin was found to be significant. Of invasive procedures, reintubation, of concomitant diseases, diabetes mellitus and coronary artery disease were found to be significant risk factors. E. faecium was detected in all VRE-colonized patients developing VRE bacteraemia.