Epidemiology, Clinical Features And Outcome Of Bacteriemia Episodes By Carbapenemase-Producing And Non Carbapenemase-Producing Enterobacteriaceae

Background: Carbapenemase-producing Enterobacteriaceae (CPE) is a public health problem due to their spectrum of infections and their high mortality. The aim of this study was to describe the epidemiology, clinical features and outcome of bacteremia by CPE compared to non-CPE. Methods & Materials: Retrospective cohort study. Enterobacteriaceae bacteremia episodes from January 2015 to December 2016 were included. The presence of genes coding for major carbapenemases (I.e. blaVIM, blaNDM, blaIMP, blaKPC and blaOXA-48) was investigated by polymerase chain reaction using specific primer. Chi square analysis and Kruskal-Wallis test were used for categorical and for continuous variables, respectively. To identify risk factors for 7-day and 30-day mortality a multivariate stepwise logistic regression analysis was performed. Results: We included 67 episodes (67,2% male): 14 (23,2%) CPE and 53 (76,8%) non-CPE. CPE isolates were blaKPC (78,5%), blaOXA (14,2%) and blaNDM (7,14%). Klebsiella spp (CPE: 85,7% vs non-CPE: 41,5%) was the most frequently isolated pathogen. The mean days of hospitalization until bacteremia episode and ICU admission in CPE vs non-CPE were: 26,6 vs 8,2 (p = 0.016) and 78% vs 45% (p = 0.027) respectively. The most common source of bacteremia was catheter-related in the CPE group (45% vs 18%; p = 0,005) and intra-abdominal in the non-CPE group (52% vs 9,1%; p = 0,009). Adequate empirical antibiotic treatment was similar: 64% vs 77%; p = 0.31. The risk of death at 7-day was 6.8 times higher in the CPE group compared to the non-CPE group (OR 6.8 CI 95% 1.1-40; p = 0,006) and mortality at 30-day was also higher in the CPE group (OR 4.9, 95% CI 1.1-20, p = 0.011). In multivariate analysis, Pitt bacteremia score > 4 (OR 20, 95% CI = 3,7- 40, p = < 0,0001), APACHE II score > 15 (OR 19, 95% CI 2,5-46, p = 0,0004), shock (OR 36, 95% CI 4,5-55, p = < 0,0001), CPE (OR 4,8, 95% CI 1,1-20, p = 0,01) were risk factors for 30-day mortality. Conclusion: Patients with Enterobacteriaceae bacteremia were slightly different regarding epidemiology and clinical presentation. CPE episodes had a much higher early and late mortality than non CPE, and was one of the independent prognostic factors. It is essential to improve early diagnosis and adequate treatment in patients at risk.