Influence of Probiotics on the Development of Clostridioides difficile Infection in Patients Receiving Fluoroquinolones.

Fluoroquinolones are associated with an increased risk of Clostridioides difficile infection (CDI). Probiotic supplementation has been shown to reduce the risk of antibiotic-associated diarrhea with variable effects on CDI. The objective of this study was to evaluate receipt of probiotics on development of primary CDI among hospitalized patients receiving fluoroquinolones. A retrospective cohort was evaluated that consisted of two groups of 100 patients each, admitted August 2018 through August 2020 that received ≥3 days of definitive monotherapy with levofloxacin or ciprofloxacin within 72 h of admission. Primary outcome was incidence of CDI. Secondary outcomes included rates of C. difficile diagnostic stool testing, additional infectious diagnostic testing, and non-CDI related gastrointestinal side effects. Patients on fluoroquinolones who received probiotics had a non-statistically significantly lower incidence in overall cases of CDI compared to those who did not receive probiotics (0% vs. 3%, p = 0.246). Patients who received probiotics had statistically significantly fewer C. difficile diagnostic stool tests performed (4% vs. 16%, p = 0.005) and fewer additional infectious diagnostic testing performed (4% vs. 10%, p = 0.096), respectively. Further research is warranted to optimize and standardize probiotic prescribing in high-risk patients.