Risk factors and outcomes of carbapenem-nonsusceptible Escherichia coli bacteremia: A matched case–control study

BackgroundInfections due to carbapenem-resistant Enterobacteriaceae have been the emerging problem worldwide. This primary object of this study was to understand the risk factors and clinical outcomes of carbapenem-nonsusceptible Escherichia coli (CNSEc) bacteremia.MethodsWe conducted a matched case–control study in a 3,715-bed tertiary care medical center in northern Taiwan. The controls were selected among patients with carbapenem-susceptible E coli and were matched with CNSEc for bacteremia.ResultsFifty-one patients were included in this study (17 cases and 34 controls). Bivariate analysis showed that prior exposure to carbapenems (p < 0.001), stay in intensive care units (p = 0.016), placement of central venous catheters (p = 0.001), chronic liver diseases (p < 0.001), uremia with regular dialysis (p = 0.004), and mechanical ventilation (p = 0.004) were associated with CNSEc bacteremia. Multivariate analysis revealed that prior exposure to carbapenems [odds ratio (OR), 29.17; 95% confidence interval (CI), 1.76–484.70; p = 0.019], uremia with regular dialysis (OR, 98.58; 95% CI, 4.02–999; p = 0.005) and chronic liver diseases (OR, 27.86; 95% CI, 2.31–335.83; p = 0.009) were independent risk factors for CNSEc bacteremia. Compared with carbapenem-susceptible E coli group, CNSEc group had a longer hospital stay (68.4 days vs. 35.8 days; p = 0.04) and a higher disease severity, as indicated by a Pittsburgh bacteremia score greater than or equal to 4 (5.6% vs. 2.5%; p = 0.015). Patients with CNSEc bacteremia had a higher overall in-hospital mortality rate (94.12% vs. 50.00%; p = 0.002), but there was no difference in the 28-day mortality between these two groups.ConclusionsCNSEc bacteremia would lead to a poor outcome among patients with prior exposure to carbapenems, chronic liver disease, and uremia with regular dialysis.