Risk factors and outcomes associated with persistent vancomycin resistant Enterococcal Bacteremia

Abstract

Background: Prior studies have identified that vancomycin resistant enterococcus (VRE) bacteremia that persists for four days or more is an independent predictor of mortality. Despite this, there is no published data to identify those patients at highest risk of developing persistent VRE bacteremia. Methods: This was a single center, retrospective, case-control study of adult patients with a VRE bloodstream infection (BSI). Case patients were those with persistent bacteremia (≥ 4 days despite VRE-directed therapy) and control patients were those with non-persistent bacteremia. Logistic regression was used to assess risk factors associated with persistent VRE BSIs. Secondary outcomes included in-hospital mortality, recurrent bacteremia, and breakthrough bacteremia. Results: During the study period, 24/108 (22%) patients had persistently positive blood cultures. Risk factors for persistent bacteremia included severe neutropenia (OR 2.13), 4 out of 4 positive index blood cultures (OR 11.29) and lack of source control (OR 11.88). In an unadjusted analysis, no statistically significant differences in in-hospital mortality (58% versus 40%; p = 0.121), recurrent bacteremia (17% versus 6%; p = 0.090), or breakthrough bacteremia (13% versus 7%; p = 0.402) were observed between groups. Conclusion: Patients with severe neutropenia, 4 out of 4 positive index blood culture bottles, and lack of source control were more likely to develop persistent VRE bacteremia despite directed antibiotic treatment.