Evaluation of Oral Amoxicillin/Clavulanate for Urinary Tract Infections Caused by Ceftriaxone Non-Susceptible Enterobacterales

Urinary tract infections (UTIs) are one of the most common infections and are frequently caused by Gram-negative organisms. The rise of resistant isolates has prompted evaluation of alternative therapies, including amoxicillin-clavulanate which has potent activity against Ambler class A enzymes. This study sought to evaluate clinical outcomes of patients with ceftriaxone non-susceptible UTIs receiving amoxicillin-clavulanate or standard of care (SOC). This was a single-center, retrospective, cohort study of adult patients with urinary tract infections caused by a ceftriaxone non-susceptible pathogen who received amoxicillin-clavulanate or SOC. The primary outcome was clinical failure at 90 days. Secondary outcomes included time to failure, isolation of a resistant organism, and hospital length of stay. Fifty-nine patients met study inclusion: 26 received amoxicillin/clavulanate and 33 received SOC. Amoxicillin-clavulanate recipients did not have higher failure rates compared to SOC recipients. For patients requiring hospital admission, hospital length of stay was numerically shorter with amoxicillin-clavulanate. The frequency of amoxicillin-clavulanate and carbapenem-resistant organisms did not differ significantly between groups. Amoxicillin-clavulanate may be a useful alternative therapy for the treatment of ceftriaxone non-susceptible Enterobacterales UTIs.

1842. Intravenous to Oral Antibiotic Stepdown for Uncomplicated Streptococcal Bacteremia

Background

Historically, intravenous (IV) antibiotics have been the standard of care for the treatment of bloodstream infections (BSIs). IV antibiotic use predisposes patients to line-related complications and is associated with increased length of stay (LOS) and treatment costs as compared to oral (PO) antibiotics. The purpose of this study was to compare the efficacy and safety of IV therapy versus PO stepdown for uncomplicated Streptococcal BSIs.

Methods

This single-center, retrospective, non-inferiority study included adults who had Streptoccoccus spp. in blood cultures with susceptibilities reported, < 48 hours of positive blood cultures, and were treated for the BSI. Patients were excluded if they had polymicrobial bacteremia, mortality prior to treatment completion, unattainable source control, or a complicated infection. The primary outcome was clinical success, defined as absence of infection recurrence, infection-related readmission, and infection-related mortality at 90 days. Secondary outcomes included individual components of composite endpoint, microbiological success, LOS, IV-line associated complications, and antibiotic-associated adverse events.

Results

Of 79 patients included, 36 patients (45.6%) received IV for the full course of therapy and 43 (54.4%) received PO stepdown. Baseline characteristics were similar between groups. The most common sources were skin and soft tissue (34.6%) and oropharyngeal (13.6%). The median duration of IV therapy in PO stepdown patients was 4.4 days (IQR 2.7 – 6.9). Amoxicillin/clavulanate (44%) and cefdinir (24%) were the most common PO agents. Clinical success occurred in 94% of IV only patients and 91% of PO stepdown patients (p = 0.573). No infection-related deaths or recurrences occurred. Line complications were more frequent in patients receiving IV compared to PO stepdown therapy (14% vs. 0%, p = 0.015). LOS was lower in the PO stepdown group (11 vs. 6 days, p < 0.001).

Conclusion

This study strengthens the hypothesis that PO stepdown therapy may be non-inferior to IV therapy for clinical success with a trend towards decreased LOS and line complications. However, this study was not powered to meet statistical significance. We are collaborating with several other centers to determine the true impact of this intervention.

Disclosures

All Authors: No reported disclosures.