The clinical efficacy of faecal microbiota transplantation: An umbrella review of randomized controlled trials

INTRODUCTION: Faecal microbiota transplantation (FMT) therapeutic strategy has been associated with positive outcomes in multiple diseases. We conducted an umbrella review of the meta-analysis to summarize the available evidence and assess its credibility. METHODS: We evaluated a meta-analysis of randomized controlled trials that investigated the efficacy and safety of FMT for any condition. We used the random-effects model to obtain estimates and corresponding 95% confidence intervals, heterogeneity estimates, and small-study effects. We used AMSTAR 2 to assess methodological quality and GRADE tools to grade the evidence. RESULTS: Seven meta-analyses with a total of 33 outcomes were included in the current umbrella review to evaluate the efficacy and safety of FMT. Overall, there is a moderate certainty of evidence supporting the associations of the use of FMT with better clinical remission in patients with Clostridium difficile infection (RR = 1.74; 95% CI: 1.37-2.22) and inflammatory bowel disease (RR = 1.70; 95% CI: 1.12-2.56). A very low certainty evidence supports the use of FMT to treat antibiotic-resistant bacteria (RR = 5.67; 95% CI: 2.20-14.63) and functional constipation (RR = 1.35; 95% CI: 1.14-1.60) but does not support irritable bowel syndrome (RR = 1.08; 95% CI: 0.65-1.77). DISCUSSION: The umbrella review of the current meta-analysis demonstrates that FMT intervention is associated with positive outcomes for several diseases. However, the credibility of the evidence is not high. Further high-quality randomized controlled trials should be carried out to improve the strength and credibility of the evidence base.