1072. Streamlining to Oral β-Lactam vs. Fluoroquinolone as Definitive Therapy for Enterobacteriaceae Bacteremia

BACKGROUND: Oral treatment strategies for Enterobacteriaceae bacteremia (EB) are controversial, with both β-lactams (BL) and fluoroquinolones (FQ) used in clinical practice. FQ may be preferred for their high bioavailability, but other oral antibiotics are needed due to concerns of resistance and adverse effects. As an effort to facilitate antibiotic stewardship, BL should be explored as an additional oral option for EB treatment. METHODS: This retrospective study compared clinical characteristics and outcomes in patients with EB treated with BL vs. FQ as definitive oral therapy between January 2013 and July 2017. Adult patients diagnosed with their first incidence of EB and transitioned from IV antibiotics to either study antibiotic class were included. Primary and secondary outcomes assessed recurrence, collateral damage, readmission, and all-cause mortality. RESULTS: A total of 173 patients were included (BL n = 59, FQ n = 114). Median age was 70 years, Pitt bacteremia score was 2 (range 0–7), and Charlson Comorbidity Index was 5 (0–12); all were comparable between groups. Urinary source of infection was most common (57%). The majority of oral BL courses used cefpodoxime (63%). More patients in FQ vs. BL had a prior transplant (9% vs. 0%, P = 0.05), presence of abscess (11% vs. 0%, P = 0.01), and Infectious Diseases consultation (63% vs. 34%, P = 0.0001). Onset of EB in an intensive care unit was more common in BL vs. FQ (24% vs. 10%, P = 0.01). Median duration of IV and oral therapy was 5 vs. 4 days, P = 0.22 and 11 vs. 12 days, P = 0.17 in BL and FQ, respectively. Recurrence within 90 days was 7% in BL and 4% in FQ, P = 0.49 (adjusted OR 1.44, 95% CI 0.31–6.66; P = 0.64). Multivariate analysis identified liver cirrhosis (OR 16.89, 95% CI 1.06–268.32; P = 0.05) as an independent predictor of recurrence within 90 days. All secondary outcomes were similar between BL vs. FQ: superinfection within 90 days (10% vs. 9%, P = 0.76), C. difficile infection within 90 days (3% vs. 1%, P = 0.27), 30-day readmission (15% vs. 20%, P = 0.43), all-cause 30-day mortality (0% vs. 3%, P = 0.55). CONCLUSION: In our cohort of patients with EB, clinical outcomes were similar between those treated with oral BL compared with FQ. Oral BL may be considered for definitive treatment of EB, although further investigation in larger studies is needed. DISCLOSURES: All authors: No reported disclosures.