1459. Oral Cephalosporins vs. Fluoroquinolones for the Empiric Treatment of Acute Uncomplicated Pyelonephritis

BACKGROUND: The Infectious Diseases Society of America guidelines for the treatment of acute uncomplicated pyelonephritis (AUP) recommend oral fluoroquinolones (FQs) as a first-line agent in patients not requiring hospitalization. However, with increasing rates of FQ and trimethoprim/sulfamethoxazole resistance, oral β-lactams are attractive agents due to improved empiric susceptibility patterns at our institution. The current guideline advises caution when using oral β-lactams due to concern for inferior efficacy, but studies specifically evaluating the efficacy of oral cephalosporins (CPHs) in AUP are limited. The purpose of this study was to provide additional evidence for the safe and effective use of oral CPHs for empiric treatment of AUP. METHODS: Retrospective chart review was performed on all patients prescribed oral CPHs or FQs for AUP from the Emergency Department (ED) at Parkland Memorial Hospital between September 2017 and July 2018. The primary endpoint was treatment failure within 30 days, defined as ED return due to any cause or modification to an alternative antibiotic. Secondary endpoints included ED return within 30 days due to continued symptoms of AUP, documented adverse drug reactions (ADRs), and C. difficile infection (CDI) within 30 days. RESULTS: Of the 333 patients included in the study, treatment failure occurred in 72 (21.6%) patients and was similar between oral FQs and CPHs (21.4% vs. 21.7%). A higher rate of treatment failure was observed for first-generation (1GC) CPHs compared with second-generation (2GC) or third-generation (3GC) CPHs (19/51 [43.1%] vs. 18/107 [16.8%] vs. 9/68 [13.2%]). The primary reason for treatment failure was modification to an alternative antibiotic, and was highest for oral 1GC, followed by FQs, then 2GC and 3GC (19/51 [37.3%] vs. 14/107 [13.1%] vs. 11/107 [10.3%] vs. 4/68 [5.9%]). Rates of return to the ED for continued symptoms of AUP were found to be lower for oral CPHs (8/226 [3.5%]) vs. FQs (9/107 [8.4%]). Documented ADRs were low (5/333 [1.5%]) and none developed CDI. CONCLUSION: Oral CPHs appear to be as safe and effective as FQs for the empiric treatment of AUP. In concordance with the susceptibility data of our institutional antibiogram, 2GC and 3GC were observed to have a lower rate of treatment failure compared with 1GC and FQs. DISCLOSURES: All authors: No reported disclosures.