Effectiveness of Carbapenem-Sparing Antibiotics Versus Carbapenems for Treating Non-Bacteremic Extended-Spectrum Beta-Lactamase-Producing Enterobacterales Infections

Introduction: Extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) pose a significant public health threat. While carbapenems are known to be superior in treating bacteremic infections, the evidence is unclear for non-bacteremic infections. Objective: To assess the effectiveness of carbapenem-sparing therapies compared to carbapenems for non-bacteremic ESBL-E infections. Methodology: This is a retrospective observational cohort study involving patients aged 18 years or older with confirmed diagnoses of ESBL-E non-bacteremic infections who received either carbapenems or carbapenem-sparing targeted therapy during the study period. The primary outcomes were clinical cure and 30-day all-cause mortality. Secondary outcomes included microbiological eradication, recurrence of ESBL-E infection within 6 months, and the 30-day incidence of new multidrug-resistant infections. Results: The study included 216 patients: 117 in the carbapenem group and 99 in the carbapenem-sparing group. Both groups showed no significant differences in 30-day all-cause mortality and clinical resolution. However, notable statistical differences were observed in three secondary outcomes: the carbapenem group had a higher recurrence rate of ESBL infections (RR 1.65, 95% CI: 1.05–2.59, P = 0.025) and more secondary multidrug-resistant infections (RR 1.92, 95% CI: 1.11–3.31, P = 0.015), including carbapenem-resistant Enterobacterales infections (RR 2.26, 95% CI: 1.10–4.63, P = 0.020). Conclusion: The study demonstrates that carbapenem-sparing therapies for ESBL-E nonbacteremic infections are non-inferior to carbapenems, with comparable 30-day all-cause mortality, clinical cure, and bacteriological resolution rates. Additionally, carbapenem-sparing options showed lower recurrence rates of ESBL-E infections and reduced development of secondary multidrug-resistant infections, including CRE infections.