Background: The rising prevalence of infections caused by extended-spectrum β-lactamase (ESBL)–producing bacteria increases reliance on carbapenems, which intensifies selection pressure for the emergence of carbapenem-resistant Enterobacteriaceae (CRE). Whether noncarbapenem (nC) antibiotics can be safely used in this setting remains incompletely understood. Objective: To examine the safety of carbapenem stewardship in this population, we compared outcomes of uncomplicated ESBL bacteremia treated with a carbapenem to those treated with a noncarbapenem regimen. Methods: A retrospective chart review of patients with ESBL bacteremia from 2014 to 2018 in a 5-hospital regional health system was conducted. Patients aged <18 years, with polymicrobial bacteremia, whose infections required a prolonged length of antibiotic therapy (LOT), or who died on antibiotic treatment or transitioned to hospice, were excluded. Groups were stratified based on the antibiotic regimen with the highest number of treatment days during the treatment course. Outcome measures included empiric and definitive length of therapy (LOT), 30-day all-cause mortality, 90-day readmission, recurrence of ESBL bacteremia, hospital length of stay (LOS), incidence of Clostridioides difficile infection (CDI) and adverse drug events, obtained by Wilcoxon rank-sum testing, χ2 test, and Fisher exact test, as applicable. Results: In total, 112 unique patients had ESBL bacteremia; 42 were excluded, leaving 70 for analysis. Of these, 57 were treated with a carbapenem regimen and 13 patients were treated with a noncarbapenem regimen: 9 ciprofloxacin, 3 gentamicin, 1 TMP-SMX. Patient baseline and antibiotic regimen characteristics were similar (Table 1). The most common organism was E. coli, and the most common source was urinary. A similar proportion of each group received ESBL-active empiric antibiotics. There were no significant differences in total effective antibiotic LOT, 30-day all-cause mortality, 90-day readmission, or recurrence of ESBL bacteremia (Table 2). A nonsignificant trend in hospital LOS was observed in the noncarbapenem group (11 vs 6 days; P = .055). Conclusions: Although the sample size was small, these multicenter data suggest that noncarbapenem treatment of ESBL bacteremia may be safe and effective. Pending confirmatory studies, ESBL bacteremia may be an important target for carbapenem stewardship.

Funding: None

Disclosures: None