Utilizing antibiotics to prevent Clostridioides difficile infection: does exposure to a risk factor decrease risk? A systematic review

Background: Antibiotic use is a major risk factor for Clostridioides difficile infection (CDI). However, antibiotics recommended for CDI treatment are being utilized in clinical practice as prophylactic agents. Objectives: To comprehensively summarize and critically evaluate the published literature investigating the effectiveness of antibiotic CDI prophylaxis. Methods: A systematic search for relevant literature was conducted in PubMed and ClinicalTrials.gov. Two investigators independently screened each article for inclusion, and the references of the included articles were studied to identify additional relevant articles. Data extraction and an assessment of risk of bias was completed for all included studies. Unadjusted risk ratios and 95% CI were calculated for each study, with CDI being the outcome variable and prophylaxis (prophylaxis versus control) representing the exposure. Results: In total, 13 articles were identified in PubMed and 9 ongoing or unpublished trials were identified in ClinicalTrials.gov. The effect of antibiotic prophylaxis on CDI rates varied between studies; however, most favoured the use of antibiotic prophylaxis. Conclusions: The authors of this review conclude that the current literature carries a high risk of bias and the results should be interpreted with caution.