Title: Impact of Concomitant Antibiotic Use on Treatment Outcomes in Patients with
Clostridioides difficile Infection Receiving Fidaxomicin.
Authors:Sonali Chikersal, Dahlia Kaiser, Jill Dunning
Background:
Clinical studies have demonstrated increased clinical cure rates in patients receiving fidaxomicin compared to vancomycin with concomitant antibiotics (CAs). However, there is limited evidence on the impact of discontinuing or de-escalating CAs on patients receiving fidaxomicin. This study aims to provide insight on the impact of discontinuation or de-escalation of CAs on treatment outcomes for patients receiving fidaxomicin for CDI treatment.
Methods:
This retrospective cohort study was performed in a muti-site healthcare system from September 26th, 2022, to January 29th, 2025. Electronic medical records were reviewed to identify adult patients hospitalized within AdventHealth Central Florida Division with confirmed CDI and receiving CAs. Key inclusion criteria were age 18 years or older, positive
Clostridioides difficile toxin test, and receiving one or more CAs for an infection other than CDI at the time of the fidaxomicin order. Key exclusion criteria were fulminant infection and patients who received IV metronidazole or oral vancomycin during the treatment period. Data was collected on patient demographics, comorbidities, antibiotic history, CDI severity markers, mortality, and hospital length of stay. The primary outcome was the rate of treatment success. Secondary outcomes include risk factors for treatment failure, in-hospital mortality, and hospital length of stay.
Results: In this study, 56 patients met the inclusion criteria. Of this population, 28 (50%) were female, mean age was 67 years old, 8 (14.3%) had a prior episode of CDI, 6 (8.9%) had severe infection, and mean length of stay was 16.2 days. There was no significant difference for the treatment success
outcome (100% vs 86.8%; P = 0.164) and mortality (0% vs 2.6%; P = 1.00) between the de-escalation/discontinuation group and CA group, respectively. The length of stay was significantly shorter in the de-escalation/discontinuation group compared to the CA group (6.5 days vs 14 days; P = 0.003). Additionally, there was no significant difference in outcomes of treatment success in patients receiving probiotics (89.4% vs 91.8%; P = 1.00), H2 receptor antagonists (88.9% vs 91.5%; P = 1.00), and proton pump inhibitors (90% vs 91.4%; P = 1.00).
Conclusions: We did not identify a significant impact on treatment success between groups that had antibiotics de-escalated or discontinued and those who did not. Though, patients who had antibiotics discontinued or de-escalated had a significantly shorter hospital length of stay compared to the patients who received CAs. A larger sample size will be needed to identify the true impact of this incidental finding.
