Comparative Effectiveness and Safety of Fecal Microbiota Transplantation in Ulcerative Colitis: An Updated Systematic Review and Meta-Analysis.

INTRODUCTION

Fecal microbiota transplantation (FMT) is a potential therapy for ulcerative colitis (UC). Evidence has expanded, but the impact of delivery route on efficacy and safety remains uncertain.

METHODS

We systematically searched PubMed, Embase, Cochrane Library, Web of Science and China National Knowledge Infrastructure (CNKI) from inception to October 2025 for randomized controlled trials (RCTs) comparing donor-derived FMT with placebo/sham or autologous FMT in patients with UC. Primary outcomes were clinical and endoscopic remission at induction (8-12 weeks). Adverse events (AEs) were secondary. Random effect models generated risk ratios (RRs) with 95% CIs. Pre-specified subgroup analyses compared delivery routes (colonoscopy, rectal enema, combined colonoscopy + enema, nasoduodenal infusion, oral capsules).

RESULTS

Sixteen RCTs were included. Overall, FMT improved clinical remission (RR = 1.81, 95% CI: 1.41-2.31; I2 = 0%) and endoscopic remission (RR = 1.74, 95% CI: 1.00-3.01; I2 = 45.5%). By route, significant effects were seen for colonoscopy (RR = 1.58, 95% CI 1.05-2.37), rectal enema (RR = 1.62, 95% CI 1.04-2.54) and combined colonoscopy + enema (RR = 2.39, 95% CI 1.47-3.89) for clinical remission; nasoduodenal and oral capsule results were imprecise. For endoscopic remission, the combined route showed the most consistent benefit (RR = 2.19, 95% CI 1.04-4.62). AEs did not differ from control (RR = 1.03, 95% CI 0.90-1.18; I2 = 11.2%).

CONCLUSIONS

FMT improves induction-phase clinical and endoscopic remission in patients with UC without increasing AEs. Efficacy appears route-dependent, with colonoscopy + enema demonstrating the largest effect. Head-to-head trials optimizing route and dosing with longer follow-up are warranted.