P-992. Impact of Ertapenem De-restriction on Hospital Length of Stay for ESBL-producing Enterobacterales Bloodstream Infections

Abstract Background Traditional antimicrobial stewardship initiatives aimed at reducing drug acquisition expenditures may fail to capture overall healthcare costs including increased hospital length of stay (LOS). Meropenem (MEM) had historically been utilized at our institution for treatment of extended-spectrum beta-lactamase producing Enterobacterales (ESBL-E) bloodstream infections (BSI) due to the high cost of ertapenem (ETP). Drugs requiring multiple daily infusions like MEM are associated with additional expenses for nurse time, intravenous tubing, admixture fluids, syringes and waste disposal compared to once-daily ETP and have also been associated with increased LOS. We aimed to quantify differences in LOS and other associated healthcare costs for patients with ESBL-E BSI treated with MEM versus ETP following de-restriction of ETP for Infectious Diseases providers in the inpatient setting.Baseline patient characteristics.Abbreviations: BMI = body mass index; BMT = bone marrow transplant within the previous 12 months; CCI = Charlson Comorbidity Index; ETP = ertapenem; HIV = human immunodeficiency virus; ICU = intensive care unit; ID = infectious diseases; IQR = interquartile range; MEM = meropenem; NS = non-significant; SOT = any history of solid organ transplantLength of stay, antimicrobial use, and patient outcomes.Abbreviations: CDI = C. difficile infection; DOT = days of therapy; ETP = ertapenem; ICU = intensive care unit; IQR = interquartile range; LOS = length of stay; MEM = meropenem; NS = non-significant Methods This retrospective study included patients with ceftriaxone-resistant E. coli or K. pneumoniae BSIs between February 1, 2023 and March 31, 2025. Patients were included if they received at least 72 hours of therapy with ETP or MEM. Patients with polymicrobial bacteremia, those receiving combination therapy for > 72 hours, or infections without documented source control were excluded.Raincloud plots of LOS for (a) overall and (b) non-ICU cohorts.a) LOS was significantly decreased in the ETP group for the overall study cohort (median 7 [IQR: 6-10] versus 10 days [IQR: 7-18], p