Appropriateness of Empirical Treatment and Outcome in Bacteremia Caused by Extended-Spectrum-beta-Lactamase-Producing Bacteria

We studied clinical characteristics, appropriateness of initial antibiotic treatment, and other factors associated with day 30 mortality in patients with bacteremia caused by extended-spectrum-beta-lactamase (ESBL)-producing bacteria in eight Dutch hospitals. Retrospectively, information was collected from 232 consecutive patients with ESBL bacteremia (due to Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae) between 2008 and 2010. In this cohort (median age of 65 years; 24 patients were = 3, an age of >= 75 years, intensive care unit (ICU) stay at bacteremia onset, a non-UTI bacteremia source, and presentation with severe sepsis, but not inappropriate therapy within <24 h (adjusted odds ratio [OR], 1.53; 95% confidence interval [CI], 0.68 to 3.45), were associated with day 30 mortality. Further assessment of confounding and a stratified analysis for patients with UTI and non-UTI origins of infection did not reveal a statistically significant effect of inappropriate therapy on day 30 mortality, and these results were insensitive to the possible misclassification of patients who had received beta-lactam-beta-lactamase inhibitor combinations or ceftazidime as initial treatment. In conclusion, ESBL bacteremia occurs mostly in patients with comorbidities requiring frequent hospitalization, and 84% of episodes were health care associated. Factors other than inappropriate therapy within <24 h determined day 30 mortality