Long-term Safety of Fecal Microbiota Transplantation for Recurrent Clostridioides difficile Infection

Fecal microbiota transplantation (FMT) is highly effective for treating recurrent Clostridioides difficile infection (CDI), with emerging data on intermediate and long-term safety.

A prospective survey-based study was conducted (September 2012-June 2018) in patients undergoing FMT for recurrent CDI. Data on demographics and comorbidities were abstracted from medical records. Patients were contacted at 1 week, 1 month, 6 months, 1 year (short-term), and ≥2 years post-FMT (long-term). Symptoms and new medical diagnoses were recorded at each time point. Data were weighted to account for survey nonresponse bias. Multivariate logistic regression models for adverse events were built using age (per 10-year increment), sex, time of survey, and comorbidities. P < .05 was considered statistically significant.

Overall, 609 patients underwent FMT; median age was 56 years (range, 18-94), 64.8% were women, 22.8% had inflammatory bowel disease (IBD). At short-term follow-up (n = 609), >60% of patients had diarrhea and 19%-33% had constipation. At 1 year, 9.5% reported additional CDI episodes. On multivariable analysis, patients with IBD, dialysis-dependent kidney disease, and multiple FMTs had higher risk of diarrhea; risk of constipation was higher in women and lower in IBD (all P < .05). For long-term follow-up (n = 447), median time of follow-up was 3.7 years (range, 2.0-6.8). Overall, 73 new diagnoses were reported: 13% gastrointestinal, 10% weight gain, 11.8% new infections (all deemed unrelated to FMT). Median time to infections was 29 months (range, 0-73) post-FMT.

FMT appears safe with low risk of transmission of infections. Several new diagnoses were reported, which should be explored in future studies.