P1335 Clostridium difficile infection in patients with Inflammatory Bowel Disease: a comparative analysis before and after the COVID-19 pandemic

Abstract Background Clostridium difficile (C. diff) infection is a major cause of hospital-acquired diarrhoea, with rising incidence, particularly among patients with inflammatory bowel disease (IBD). This study aimed to describe the clinical characteristics and outcomes of hospitalised IBD patients with C. diff infection, comparing 2017–2020 (pre-pandemic) and 2021–2024 (post–COVID-19 pandemic). Methods We retrospectively analysed 59 hospitalised IBD patients with C. diff infection. Demographic data, disease characteristics, prior and in-hospital treatments, length of stay, and clinical outcomes were recorded. Comparative analyses between the two periods were conducted, and factors associated with prolonged hospitalisation were evaluated using multivariate analysis. Results C. diff-related hospitalisations increased fivefold post-pandemic (49 vs 10 patients). Disease characteristics were similar, although patients were slightly younger in the latter period. Overall, 64% were male, mean age 43 years. Ulcerative colitis (UC) was the predominant subtype (75%). In 13 patients (19%), IBD and C. diff infection were diagnosed concurrently. Prior treatments included proton pump inhibitors (n = 5), antibiotics (n = 9), mesalazine (n = 23), corticosteroids (n = 10), immunosuppressants (n = 11), and biologics (n = 22; 37%), including anti-TNF, anti-integrin, anti-IL-12/23, JAK inhibitors, and combination therapies. All patients received vancomycin; fidaxomicin was given in 44% of cases, and tigecycline in five severe cases. Combination therapy was reserved for the most severe infections. No patient required surgery. Re-hospitalisation for recurrent C. diff occurred in 16 patients. Mean length of stay was 17 days, longer in UC than Crohn’s disease (p 0.05). Sex, use of PPIs, antibiotics, or immunosuppressive therapy did not significantly affect length of stay. Modification of IBD therapy post-infection was required in 26 patients and was associated with prolonged hospitalisation (+9.4 days, p = 0.025). Multivariate analysis identified age and IBD subtype as the only independent predictors of prolonged hospitalisation. Conclusion A substantial post-pandemic increase in C. diff-related hospitalisations among IBD patients was observed. While the underlying mechanisms remain uncertain, the COVID-19 pandemic and increased antimicrobial use may have contributed. Ulcerative colitis and older age were associated with poorer outcomes and longer hospital stays. References: 1. Louie TJ, Miller MA, Crook DW, et al. Recurrence of Clostridium difficile infection in patients with inflammatory bowel disease: the RECIDIVISM study. Clin Gastroenterol Hepatol. 2016;14(5):681687. doi:10.1016/j.cgh.2015.12.023 2. Nguyen GC, Kaplan GG, Harris ML, et al. 90day specific readmission for Clostridium difficile infection after hospitalization with an inflammatory bowel disease flare: outcomes and risk factors. J Crohns Colitis. 2020;14(10):13531360. doi:10.1093/ecco-jcc/jjaa046 3. Mo Y, Li J, Zhang H, et al. Association of Clostridium difficile infection with clinical outcomes of patients with inflammatory bowel disease: a meta-analysis. J Gastroenterol Hepatol. 2025;40(7):20252033. doi:10.1111/jgh.16520 4. Colman RJ, Rubin DT. Clostridium difficile in inflammatory bowel disease. Nat Rev Gastroenterol Hepatol. 2023;20(1):3546. doi:10.1038/s41575-022-00704-8 5. Lee YR, Chen CY, Lin CJ, et al. Impact of Clostridioides difficile infection on clinical outcomes in hospitalized IBD patients and the role of fecal microbiota transplantation: a retrospective cohort study. Kaohsiung J Med Sci. 2025;41(4):700707. doi:10.1002/kjm2.70002 6. DuPont AW, Smith JK, Greenberg RN, et al. The elevated risk of recurrent Clostridioides difficile infection in patients with inflammatory bowel disease: a systematic review and meta-analysis. Inflamm Bowel Dis. 2021;27(8):12631270. doi:10.1093/ibd/izaa331 Conflict of interest: Mr. Psaroudakis, Ioannis: No conflict of interest Arna, Despoina Eleni: No conflict of interest Skouloudi, Charikleia: No conflict of interest Psistakis, Andreas: No conflict of interest Fragaki, Maria: No conflict of interest Velegraki, Magdalini: No conflict of interest Coucoutsi, Constantina: No conflict of interest Karmiris, Konstantinos: No conflict of interest Theodoropoulou, Angeliki: No conflict of interest