Use of non-carbapenem antibiotics to treat severe extended-spectrum β-lactamase-producing Enterobacteriaceae infections in intensive care unit patients

Objectives: The aim of this study was to evaluate the use of non-carbapenem antibiotics to treat severe extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) infections in intensive care unit (ICU) patients.

Methods: This retrospective observational study conducted in two ICUs compared the outcomes of patients with ESBL-E infections administered a carbapenem or a non-carbapenem antibiotic as their definitive treatment. The primary outcome was treatment failure within 30 days, a composite endpoint of ESBL-E infection recurrence and 30-day mortality. Secondary outcomes included 30-day and in-hospital mortality rates, ESBL-E infection recurrence and infection(s) due to other pathogen(s).

Results: Among 107 patients included in the study, 67 received a carbapenem and 40 received a non-carbapenem antibiotic as their definitive treatment. Clinical characteristics of the two groups were similar. Comparing patients given a non-carbapenem antibiotic with those administered a carbapenem, they had similar 30-day treatment failure (43% vs. 61%, respectively; P = 0.06) and ESBL-E infection recurrence rates (25% vs. 22%; P = 0.8), but the former had lower 30-day mortality (23% vs. 45%; P = 0.02) and in-hospital mortality rates (23% vs. 49%; P = 0.005). Secondary infection rates caused by other pathogen(s), including Clostridium difficile, were comparable. Outcomes were comparable regardless of whether or not patients received an empirical carbapenem.

Conclusion: For ICU patients with severe ESBL-E infections, treatment with a non-carbapenem antibiotic was not associated with poorer outcomes compared with a carbapenem antibiotic.