Procedures in Fecal Microbiota Transplantation for Treating Irritable Bowel Syndrome: Systematic Review and Meta-Analysis

Abstract

Background: Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease with no effective treatment. Altered microbiota composition seems implicated in disease etiology and therefore fecal microbial transplantation (FMT) has emerged as a possible treatment therapy. To clarify the clinical parameters impacting FMT efficacy, we conducted a systematic review with subgroup analysis.

Methods: A literature search was performed identifying randomized controlled trials (RCTs) comparing FMT with placebo in IBS adult patients (8-week follow-up) with a reported improvement in global IBS symptoms.

Results: Seven RCTs (489 participants) met the eligibility requirements. Although FMT seems not to be effective in global improvement of IBS symptoms, subgroup analysis shows that FMT through gastroscopy or nasojejunal tube are effective IBS treatments (RR 3.03; 95% CI 1.94-4.73; I² = 10%, p < 0.00001). When considering non-oral ingestion routes, IBS patients with constipation symptoms are more likely to benefit from FMT administration (p = 0.003 for the difference between IBS subtypes regarding constipation). Fresh fecal transplant and bowel preparation seem also to have impact on FMT efficacy (p = 0.03 and p = 0.01, respectively).

Conclusion: Our meta-analysis revealed a set of critical steps that could affect the efficacy of FMT as clinical procedure to treat IBS, nevertheless more RCTs are needed.

Keywords: fecal microbiota transplantation; irritable bowel syndrome; meta-analysis; microbiome therapy; randomized controlled trials.

Figure 1

PRISMA study flow diagram describing the process of study selection.

Figure 2

Forest plot of all studies for efficacy of FMT vs. placebo on global improvement of IBS symptoms. Aroniadis et al., 2019 [31], El-Salhy et al., 2020 [32], Halkjær et al., 2018 [33], Holster et al., 2019 [34], Holvoet et al., 2020 [35], Johnsen et al., 2017 [36] and Lahtinen et al., 2020 [37].

Figure 3

Forest plot for efficacy of FMT vs placebo on global improvement of IBS symptoms by delivery method. Aroniadis et al., 2019 [31], El-Salhy et al., 2020 [32], Halkjær et al., 2018 [33], Holster et al., 2019 [34], Holvoet et al., 2020 [35], Johnsen et al., 2017 [36] and Lahtinen et al., 2020 [37].

Figure 4

Forest plot of adverse events. El-Salhy et al., 2020 [32], Halkjær et al., 2018 [33], Holster et al., 2019 [34], Johnsen et al., 2017 [36] and Lahtinen et al., 2020 [37].