Oral step-down antibiotigram-negative bacterial infections/drug therapy; bacteremia; infectious diseases; bacteremia/drug therapy; anti-bacterial agents/administration & dosage; oral administration; intravenous administration; mortalitycs, intravenous antibiotics, gram-negative bacteremia, infectious diseases


Infectious Disease | Pharmacy and Pharmaceutical Sciences



In recent years, there has been a growing body of evidence that supports oral step-down therapy for the treatment of gram-negative bacteremia. The purpose of this study was to compare outcomes for hospitalized patients who received intravenous-only (IV-only) therapy versus oral step-down therapy with low, moderate, and highly bioavailable antimicrobials for the treatment of gram-negative bacteremia.


In this retrospective, single-center, observational study, we examined data from adult patients hospitalized with gram-negative bacteremia in a 1-year period. Data analysis was performed using information collected from electronic medical records and a clinical surveillance system.


A total of 199 patients were included in this study. Patients in the IV-only group had higher Charlson comorbidity index scores at baseline and higher rates of intensive care unit admission while bacteremic (P = .0096 and .0026, respectively). The primary outcome of 30-day all-cause mortality was significantly lower in the oral step-down group (P < .0001). Secondary outcomes of 30-day bacteremia recurrence, line-associated complications, and hospital length of stay were similar between groups. The total duration of antibiotic therapy was one day longer for oral step-down patients (P = .0015) and the estimated cost of antibiotic therapy was significantly lower in this group (P < .00001).


In this retrospective study, oral step-down therapy was not associated with increased 30- day all-cause mortality. Oral step-down therapy was also more cost-effective than IV-only therapy, while both groups had similar bacteremia recurrence within 30 days.