Early alert from microbiology laboratory improves the outcome of elderly patients with Enterococcus spp bacteremia: results from a multicenter prospective study

Abstract Objectives To describe clinical features and outcome of patients with bloodstream infections (BSIs) due to Enterococcus spp and identify predictive factors of mortality. Methods This analysis is part of a prospective multicenter observational study of consecutive hospitalized patients with BSIs. The study was conducted from March 2012 to December 2012 in 31 Internal Medicine wards (IMWs) in Italy (SNOOPII study). Patients with BSI due to Enterococcus spp were selected from the whole cohort. Patient characteristics, therapeutic interventions and outcome were reviewed. A Cox-regression analysis was performed to identify factors associated with in-hospital mortality. Hazard ratio (HR) and 95% interval confidence (CI) were calculated. Results Among 533 patients with BSIs, 41 (7.7%) had a BSI by Enterococcus spp. Overall, 28 (68.3%) BSIs were caused by E. faecalis , 4 (9.7%) by E. faecium and 3 (7.3%) by E. avium, E. casseliflavus and E. gallinarum , respectively. Six (14.6%) BSIs were polymicrobial. Median age was 73 (interquartile ranges 66-85.5) years. In-hospital mortality rate was 24.4%. Polymicrobial infection (HR 9.1, 95% CI 1.295-63.949, p = 0.026), age (HR 1.261, 95% CI 1.029-1.546, p = 0.025), and SOFA score (HR 1.244, 95% CI 1.051-1.474, p = 0.011) were risk factors for in-hospital mortality. Conversely, receiving an alert from clinical microbiology laboratory before obtaining final antimicrobial susceptibility results was associated with survival (HR 0.073, 95% CI 0.007-0.805, p = 0.033). Conclusions BSIs due to Enterococcus spp in elderly are associated with high mortality. Polymicrobial infection, age and SOFA score are factors associated with poor outcome. Conversely, early alert from the microbiology laboratory improves patient’s survival.