Supplementary Material for: Outcomes of Fecal Microbiota Transfer in Patients with Recurrent Clostridioides difficile Infection: Real-World Data from a Single Center in Switzerland

Introduction: Clostridioides difficile is the most frequently reported healthcare-associated infection with around 125’000 occurrences and 3’700 deaths annually in Europe. Recurrence rates are about 20% and risk factors include age > 65 years and inflammatory bowel disease (IBD). Fecal Microbiota Transfer (FMT) has emerged as a highly effective treatment for recurrent C. difficile infection (rCDI), being successful in more than 90% of patients. This retrospective single-center study aimed to evaluate the effectiveness and safety of FMT in patients with rCDI the University Hospital Zurich. Methods: Between 2012 and 2022, 84 patients underwent FMT for rCDI at our center, of which 83 were included in the final analysis. The median patient age was 71 years (22-97 years), and the majority of patients were female (67.4%). All patients had received multiple prior courses of antibiotic treatment for C. difficile infection. Results: The success rate following a single FMT was 92.8%, increasing to 97.6% with repeated procedures. Those rates were comparable in the IBD subgroup. FMT was well tolerated. Mild adverse events were reported in 14.5% of patients, most commonly reported adverse event being ongoing IBD activity (41.7%), followed by diarrhea (25%) and abdominal pain (25%). Serious adverse events occurred in 3.6% of patients mainly related to underlying conditions. Conclusion: Our study confirms that FMT is a highly effective and well-tolerated treatment for rCDI, even in older patients with comorbidities. Importantly, FMT was successfully implemented without the use of a national stool bank, instead relying on locally processed related donor stool, highlighting its feasibility in resource-limited settings.