Efficacy of Fecal Microbiota Transplantation (FMT) for Ulcerative Colitis (UC): Systematic Review and Meta-Analysis

Introduction: Fecal microbiota transplantation has emerged as a novel therapeutic option for the treatment of diseases that involve the modification of the host gut microbiota. The application of FMT has been proposed as a treatment for patients with refractory ulcerative colitis. Methods: We performed an updated meta-analysis of the literature on FMT for UC patients using Pubmed, Scopus and Embase from 2003-2017. We included RCTs or prospective trials administering FMT to patients with UC. We included trials that assessed outcome as clinical remission post-FMT defined by either improvement or reduction of symptoms based on the validated questionnaires used, which included Mayo clinic score, IBDQ, the UCDAI, the SCCAI, or normalization of Fecal Calprotectin levels. Cohort studies describing clinical remission rates were included. Results: The literature search resulted in 109 references. We excluded 76 articles and included 5 RCTs (table 1) and 28 prospective cohort studies (table 2) enrolling 644 number of UC patients. All but one of the RCTs included UC patients with mild-moderate disease activity. Most cohort studies included patients with moderate-severe disease at enrollment. 24% of the studies utilized a combination of endoscopic infusion and enemas for the delivery of FMT. There were 5 RCTs that assessed clinical remission. The RR for clinical remission was 2.2 (95% CI 1.3-3.7, I2=29%).There were 21 cohort studies that assessed clinical remission. Using a random effects model, the pooled event rate was 32% (95% CI 23-43%, I2=52%) and increased to 41% (95% CI 30-52%, I2=29%) when studies with more than one infusion (N=11) were included. There were 16 cohort studies that rated the disease activity as moderate or severe; the event rate for response was 34% in this group (95% CI 25-44%, I2=45%); in the 5 studies reporting mild disease activity, the response rate was 19.5% (95% CI 8-41%, I2 51%) Conclusion: The study of FMT in UC patients continues to evolve with the greater need for more RCTs to fully assess the efficacy in UC patients. Based on limited clinical data, the RR for clinical remission was estimated to be approximately 2.2. Using cohort data, approximately 1/3 of patients do experience significant improvement with the use of FMT as demonstrated by validated questionnaire scores. This response appears to be greater in patients receiving multiple infusions making one consider if the use of FMT has to utility an induction and maintenance protocol for sustained efficacy.Table: RCT Studies Included in the Meta-Analysis.Table: Cohort Studies included in the Meta-Analysis.