Treatment outcomes of mild to moderate Clostridioides difficile infection in inflammatory bowel disease: an Australian experience.

Background: The incidence of Clostridioides difficile infection (CDI) in inflammatory bowel disease (IBD) is rising and associated with adverse outcomes. Optimal treatment for CDI in IBD remains unknown, with various organisations suggesting vancomycin as first-line therapy.

Aim: To compare treatment outcomes for metronidazole versus vancomycin in mild to moderate CDI in IBD.

Methods: A retrospective analysis of IBD patients with CDI between January 2015 and December 2019 was conducted. Laboratory data and clinical outcomes were examined.

Results: Forty-seven discrete episodes of CDI in 34 patients occurred during the study period. Fifty-three per cent (18) had Crohn's disease, 44% (15) ulcerative colitis and 3% (1) IBD unclassified. Six per cent (3/47) of CDI cases were severe and excluded. In 68% (30/44) of mild to moderate CDI, metronidazole was prescribed, with treatment failure in 20% (6/30), CDI recurrence in 13% (4/30) and 20% (6/30) experiencing a further CDI episode. Comparatively, vancomycin was prescribed in 23% (10/44) without any treatment failures; however, 10% (1/10) had CDI recurrence and 40% (4/10) experienced another CDI episode. No statistically significant difference was noted between metronidazole and vancomycin therapy for treatment failure (P = 0.31), CDI recurrence (P = 1.0) or further CDI episodes (P = 0.23). Proton-pump inhibitor therapy was the only risk factor associated with a higher rate of the composite outcome and remained significant on multivariate logistic regression (odds ratio 12.99 (95% confidence interval = 1.21-139.97), P = 0.03).

Conclusion: Metronidazole compared to vancomycin for treatment of mild to moderate CDI in IBD is effective however may be associated with higher rates of treatment failure.