Fecal microbiota transplantation as therapy for inflammatory bowel disease: A systematic review and meta-analysis

Background and aims: Fecal microbiota transplantation (FMT) has gained interest as a novel treatment option for inflammatory bowel diseases (IBD). While publications describing FMT as therapy for IBD have more than doubled since 2012, research that investigates FMT treatment efficacy has been scarce. We conducted a systematic review and meta-analysis to evaluate the efficacy of FMT as treatment for patients with IBD. Methods: A systematic literature search was performed through May 2014. Inclusion criteria required FMT as the primary therapeutic agent. Clinical remission (CR) and/or mucosal healing were defined as primary outcomes. Studies were excluded if they did not report clinical outcomes or included patients with infections. Results: Eighteen studies (9 cohort studies, 8 case studies and 1 randomized controlled trial) were included. 122 patients were described (79 ulcerative colitis (UC); 39 Crohn's disease (CD); 4 IBD unclassified). Overall, 45% (54/119) of patients achieved CR during follow-up. Among the cohort studies, the pooled proportion of patients that achieved CR was 36.2% (95% CI 17.4%-60.4%), with a moderate risk of heterogeneity (Cochran's Q, P=0.011; I²=37%). Subgroup analyses demonstrated a pooled estimate of clinical remission of 22% (95% CI 10.4%-40.8%) for UC (P=0.37; I²=0%) and 60.5% (95% CI 28.4%-85.6%) for CD (P=0.05; I²=37%). Six studies performed microbiota analysis. Conclusions: This analysis suggests that FMT is a safe, but variably efficacious treatment for IBD. More randomized controlled trials are needed and should investigate frequency of FMT administration, donor selection and standardization of microbiome analysis.