Background: Emerging trials suggest fecal microbiota transplantation (FMT) is a promising treatment for ulcerative colitis; however, there is a paucity of data in Crohn disease (CD).Objective: The objectives of this article are to determine whether single‐dose FMT improves clinical and endoscopic outcomes in CD patients and to identify meaningful changes in the microbiome in response to FMT.Methods: We performed a prospective, open‐label, single‐center study. Ten CD patients underwent FMT and were evaluated for clinical response (defined as decrease in Harvey‐Bradshaw Index score ≥3 at one month post‐FMT) and microbiome profile (16S ribosomal RNA sequencing) at one month post‐FMT.Results: Three of 10 patients responded to FMT. Two of 10 patients had significant adverse events requiring escalation of therapy. On microbiome analysis, bacterial communities of responders had increased relative abundance of bacteria commonly found in donor gut microbiota.Conclusions: Single‐dose FMT in this cohort of CD patients showed modest effect and potential for harm. Responders tended to have lower baseline alpha diversity, suggesting baseline perturbation of microbiota may be an indicator of potential responders to FMT in this patient population. Controlled trials are needed to further assess the efficacy and safety of FMT in CD and determine whether FMT is a viable option in this patient population.Clinicaltrials.gov number: NCT02460705.

Fecal microbiota transplant is a promising therapy for ulcerative colitis. Parameters maximizing effectiveness and tolerability are not yet clear, and it is not known how import the transmission of donor microbes to patients is. Here (clinicaltrails.gov: NCT03006809) we have tested the effects of antibiotic pretreatment and compared two modes of maintenance dose delivery, capsules versus enema, in a randomized, pilot, open-label, 2 × 2 factorial design with 22 patients analyzed with mild to moderate UC. Clinically, the treatment was well-tolerated with favorable safety profile. Of patients who received antibiotic pretreatment, 6 of 11 experienced remission after 6 weeks of treatment, versus 2 of 11 non-pretreated patients (log odds ratio: 1.69, 95% confidence interval: −0.25 to 3.62). No significant differences were found between maintenance dosing via capsules versus enema. In exploratory analyses, microbiome turnover at both the species and strain levels was extensive and significantly more pronounced in the pretreated patients. Associations were also revealed between taxonomic turnover and changes in the composition of primary and secondary bile acids. Together these findings suggest that antibiotic pretreatment contributes to microbiome engraftment and possibly clinical effectiveness, and validate longitudinal strain tracking as a powerful way to monitor the dynamics and impact of microbiota transfer.

Purpose of review: The purpose of this brief review is to investigate the current utility of fecal microbial transplantation (FMT) to ameliorate dysbiosis contributing to inflammatory bowel disease pathogenesis. Recent findings: Increasing data from randomized, controlled trials support a role for multiple FMT administrations in the induction of remission and even as a maintenance therapy in mild-to-moderate Ulcerative Colitis. Small series and one small randomized controlled trial among patients with Crohn's Disease and with pouchitis continue to produce conflicting clinical results and microbial profile data on the host and donor levels. It is not clear whether patients with Crohn's disease are more susceptible to disease flare after FMT. Novel FMT delivery systems, including oral, and early-intensity colonoscopic devices, are under investigation. Summary: The allure of minimizing the risks and cost of long-term immunosuppression via modulation of patient microbiota remains enticing, and the most recent randomized controlled data in ulcerative colitis reveals acceptable clinical remission rates. However, prior to wide adoption of FMT within the inflammatory bowel disease treatment armamentarium, large clinical trials identifying biomarkers of treatment success, ensuring safety across all indications, and cultivating optimized donor and host selection are needed.

Fecal microbiota transplant is a promising therapy for ulcerative colitis. Parameters maximizing effectiveness and tolerability are not yet clear, and it is not known how import the transmission of donor microbes to patients is. Here ( clinicaltrails.gov : NCT03006809 ) we have tested the effects of antibiotic pretreatment and compared two modes of maintenance dose delivery, capsules versus enema, in a randomized, pilot, open-label, 2×2 factorial design with 22 patients analyzed with mild to moderate UC. Clinically, the treatment was well-tolerated with favorable safety profile. Of patients who received antibiotic pretreatment, 6 of 11 experienced remission after six weeks of treatment, versus 2 of 11 non-pretreated patients (odds ratio: 1.69, 95% confidence interval: -0.25 to 3.62). No significant differences were found between maintenance dosing via capsules versus enema. In exploratory analyses, microbiome turnover at both the species and strain levels was extensive and significantly more pronounced in the pretreated patients. Associations were also revealed between taxonomic turnover and changes in the composition of primary and secondary bile acids. Together these findings suggest that antibiotic pretreatment contributes to microbiome engraftment and possibly clinical effectiveness, and validate longitudinal strain tracking as a powerful way to monitor the dynamics and impact of microbiota transfer.