The effect of faecal microbiota transplantation on abdominal pain, stool frequency, and stool form in patients with moderate-to-severe irritable bowel syndrome: results from a randomised, double-blind, placebo-controlled study

Fecal microbiota transplantation: current challenges and future landscapes

SUMMARYGiven the importance of gut microbial homeostasis in maintaining health, there has been considerable interest in developing innovative therapeutic strategies for restoring gut microbiota. One such approach, fecal microbiota transplantation (FMT), is the main "whole gut microbiome replacement" strategy and has been integrated into clinical practice guidelines for treating recurrent Clostridioides difficile infection (rCDI). Furthermore, the potential application of FMT in other indications such as inflammatory bowel disease (IBD), metabolic syndrome, and solid tumor malignancies is an area of intense interest and active research. However, the complex and variable nature of FMT makes it challenging to address its precise functionality and to assess clinical efficacy and safety in different disease contexts. In this review, we outline clinical applications, efficacy, durability, and safety of FMT and provide a comprehensive assessment of its procedural and administration aspects. The clinical applications of FMT in children and cancer immunotherapy are also described. We focus on data from human studies in IBD in contrast with rCDI to delineate the putative mechanisms of this treatment in IBD as a model, including colonization resistance and functional restoration through bacterial engraftment, modulating effects of virome/phageome, gut metabolome and host interactions, and immunoregulatory actions of FMT. Furthermore, we comprehensively review omics technologies, metagenomic approaches, and bioinformatics pipelines to characterize complex microbial communities and discuss their limitations. FMT regulatory challenges, ethical considerations, and pharmacomicrobiomics are also highlighted to shed light on future development of tailored microbiome-based therapeutics.

AGA Clinical Practice Guideline on Fecal Microbiota-Based Therapies for Select Gastrointestinal Diseases

BACKGROUND & AIMS

Fecal microbiota-based therapies include conventional fecal microbiota transplant and US Food and Drug Administration-approved therapies, fecal microbiota live-jslm and fecal microbiota spores live-brpk. The American Gastroenterological Association (AGA) developed this guideline to provide recommendations on the use of fecal microbiota-based therapies in adults with recurrent Clostridioides difficile infection; severe to fulminant C difficile infection; inflammatory bowel diseases, including pouchitis; and irritable bowel syndrome.

METHODS

The guideline was developed using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) framework to prioritize clinical questions, identify patient-centered outcomes, and conduct an evidence synthesis. The guideline panel used the Evidence-to-Decision framework to develop recommendations for the use of fecal microbiota-based therapies in the specified gastrointestinal conditions and provided implementation considerations for clinical practice.

RESULTS

The guideline panel made 7 recommendations. In immunocompetent adults with recurrent C difficile infection, the AGA suggests select use of fecal microbiota-based therapies on completion of standard of care antibiotics to prevent recurrence. In mildly or moderately immunocompromised adults with recurrent C difficile infection, the AGA suggests select use of conventional fecal microbiota transplant. In severely immunocompromised adults, the AGA suggests against the use of any fecal microbiota-based therapies to prevent recurrent C difficile. In adults hospitalized with severe or fulminant C difficile not responding to standard of care antibiotics, the AGA suggests select use of conventional fecal microbiota transplant. The AGA suggests against the use of conventional fecal microbiota transplant as treatment for inflammatory bowel diseases or irritable bowel syndrome, except in the context of clinical trials.

CONCLUSIONS

Fecal microbiota-based therapies are effective therapy to prevent recurrent C difficile in select patients. Conventional fecal microbiota transplant is an adjuvant treatment for select adults hospitalized with severe or fulminant C difficile infection not responding to standard of care antibiotics. Fecal microbiota transplant cannot yet be recommended in other gastrointestinal conditions.

Efficacy of different courses of acupuncture for diarrhea irritable bowel syndrome: A protocol for systematic review and meta-analysis

Irritable Bowel Syndrome (IBS) is the most common functional gastrointestinal disorder. As one of the most common subtypes of IBS, IBS-D can impair the patients' quality of life (QOL) and decreased work productivity. Acupuncture may be a potential treatment for patients with IBS-D. However, the treatment course of acupuncture was diverse. It is unclear what is the optimal acupuncture treatment courses for acupuncture. The efficacy and safety of different courses of acupuncture for IBS-D have not been systematically evaluated yet. The purpose of this study is to evaluate effectiveness of Acupuncture of different courses in the treatment of IBS-D and provide sufficient evidence for clinical recommendations for IBS-D. We will follow the Preferred reporting items for systematic reviews and meta-analysis protocols (PRISMA-P) guidelines to design the protocol of a systematic review and meta-analysis. This systematic review is registered in PROSPERO (CRD42023418846). We will include randomized controlled trials (RCTs) in which the efficacy of Acupuncture is compared with a placebo, sham acupuncture or Pinaverium bromide in the treatment of IBS-D with no language restrictions. The outcomes of interest will be efficiency rate and the Symptoms Severity Score. RCTs will be searched in the electronic database and Clinical Trials Registry Platform from inception to April 2023. Two independent reviewers will independently select studies, extract data from the included studies, and assess the risk of bias using the Cochrane tool. We will choose a random or fixed-effects model based on the heterogeneity index. We will use the relative risk and mean difference to estimate data with 95% CI. A stratified meta-analysis was conducted to evaluate the effect of different treatment courses of Acupuncture: 2weeks, 4weeks(or 1 months), 6 weeks, and 8 weeks. If there is significant clinical and methodological heterogeneity, we will look for the reason for heterogeneity and perform a subgroup analysis. According to the Grading of Recommendations Assessment, Development and Evaluation (GRADE), we will evaluate the evidence quality and provide the recommendation's strength.

Gut Dysbiosis in Irritable Bowel Syndrome: A Narrative Review on Correlation with Disease Subtypes and Novel Therapeutic Implications

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder characterized by chronic abdominal pain and altered bowel habits. It can be subclassified in different subtypes according to the main clinical manifestation: constipation, diarrhea, mixed, and unclassified. Over the past decade, the role of gut microbiota in IBS has garnered significant attention in the scientific community. Emerging research spotlights the intricate involvement of microbiota dysbiosis in IBS pathogenesis. Studies have demonstrated reduced microbial diversity and stability and specific microbial alterations for each disease subgroup. Microbiota-targeted treatments, such as antibiotics, probiotics, prebiotics, synbiotics, fecal microbiota transplantation, and even diet, offer exciting prospects for managing IBS. However, definitive conclusions are hindered by the heterogeneity of these studies. Further research should focus on elucidating the mechanisms, developing microbiome-based diagnostics, and enabling personalized therapies tailored to an individual's microbiome profile. This review takes a deep dive into the microscopic world inhabiting our guts, and its implications for IBS. Our aim is to elucidate the complex interplay between gut microbiota and each IBS subtype, exploring novel microbiota-targeted treatments and providing a comprehensive overview of the current state of knowledge.

Microbiota in Irritable Bowel Syndrome and Endometriosis: Birds of a Feather Flock Together-A Review

Endometriosis and irritable bowel syndrome (IBS) are chronic conditions affecting up to 10% of the global population, imposing significant burdens on healthcare systems and patient quality of life. Interestingly, around 20% of endometriosis patients also present with symptoms indicative of IBS. The pathogenesis of both these multifactorial conditions remains to be fully elucidated, but connections to gut microbiota are becoming more apparent. Emerging research underscores significant differences in the gut microbiota composition between healthy individuals and those suffering from either endometriosis or IBS. Intestinal dysbiosis appears pivotal in both conditions, exerting an influence via similar mechanisms. It impacts intestinal permeability, triggers inflammatory reactions, and initiates immune responses. Furthermore, it is entwined in a bidirectional relationship with the brain, as part of the gut-brain axis, whereby dysbiosis influences and is influenced by mental health and pain perception. Recent years have witnessed the development of microbiota-focused therapies, such as low FODMAP diets, prebiotics, probiotics, antibiotics, and fecal microbiota transplantation, designed to tackle dysbiosis and relieve symptoms. While promising, these treatments present inconsistent data, highlighting the need for further research. This review explores the evidence of gut dysbiosis in IBS and endometriosis, underscoring the similar role of microbiota in both conditions. A deeper understanding of this common mechanism may enable enhanced diagnostics and therapeutic advancements.

Irritable bowel syndrome: Epidemiology, overlap disorders, pathophysiology and treatment

Irritable bowel syndrome (IBS) is a common chronic gastrointestinal disease with a significant impact on patients' quality of life and a high socioeconomic burden. And the understanding of IBS has changed since the release of the Rome IV diagnosis in 2016. With the upcoming Rome V revision, it is necessary to review the results of IBS research in recent years. In this review of IBS, we can highlight future concerns by reviewing the results of IBS research on epidemiology, overlap disorders, pathophysiology, and treatment over the past decade and summarizing the latest research.

Fecal microbiota transplantation for irritable bowel syndrome: a systematic review and meta-analysis of randomized controlled trials

Objective

Whether fecal microbiota transplantation (FMT) in patients with irritable bowel syndrome (IBS) is effective in improving outcomes remains controversial. We assessed the safety and efficacy of FMT for patients with IBS.

Methods

In this systematic review and meta-analysis, we searched PubMed, Embase, Web of Science, the Cochrane Library, the clinicaltrials.gov and International Clinical Trials Registry Platform (ICTRP) up to February 25, 2022, updated to March 28, 2023. Randomized controlled trials (RCTs) compared the stool and capsule FMT with placebo in patients with IBS were included. Two authors independently assessed study eligibility, extracted the data, and assessed risk of bias. We did meta-analysis with RevMan, and the Stata software was used for sensitivity analysis and meta-regression. The GRADE system was used to assess the quality of evidences. Mean difference (MD) or standardized Mean difference (SMD) with 95% CI for continuous data, and risk ratios (RR) with 95% CI for dichotomous data were used with random-effects models. The primary outcomes included the clinical response rate and IBS-SSS score. This study is registered with PROSPERO: CRD42022328377.

Results

Nineteen reports from nine RCTs were included finally. Compared with the placebo, a single stool FMT could significantly decrease the IBS-SSS score at 1 month (MD=-65.75, 95%CI [-129.37, -2.13]), 3 months (MD=-102.11, 95% CI [-141.98, -62.24]), 6 months (MD=-84.38, 95%CI [-158.79, -9.97]), 24 months (MD=-110.41, 95%CI [-145.37, -75.46]), and 36 months (MD=-104.71, 95%CI [-137.78, -71.64]). It also could improve the clinical response rate at 3 months (RR=1.91, 95% [1.12, 3.25]), 24 months (RR=2.97, 95% [1.94, 4.54]), and 36 months (RR=2.48, 95% [1.65, 3.72]), and increase the IBS-QoL score at 3 months, 24 months, and 36 months. FMT did not increase the serious adverse event. The risk of bias was low, and the quality of evidence based on GRADE system was moderate in the stool FMT group. However, we did not find positive effect of capsule FMT on patients with IBS based on the current available data.

Conclusion

A single stool FMT is effective and safe for patients with IBS. However, some factors may affect the effectiveness of FMT, and the relationship between the gut microbiome and the effect of FMT for IBS is still unclear.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022328377.

Irritable Bowel Syndrome and the Gut Microbiome: A Comprehensive Review

Irritable Bowel Syndrome (IBS) is a functional disorder of the gastrointestinal tract characterized by abdominal pain and altered bowel habits. It has a prevalence of 10 to 25% in the United States and has a high disease burden, as evidenced by reduced quality of life, decreased work productivity and increased healthcare utilization and costs. IBS has been associated with several intra-intestinal and extra-intestinal conditions, including psychiatric comorbidities. Although the pathophysiology of IBS has not been fully elucidated, it involves dysregulation of communication between the brain and gut (brain–gut axis) which is associated with alterations in intestinal motility, gut permeability, visceral hypersensitivity and gut microbiota composition. The purpose of this article is to review the role the gut microbiota plays in the pathophysiology of IBS, understand factors that affect the gut microbiome and explore the microbiome as a target of treatment.

Update on treatment of abdominal pain in irritable bowel syndrome: A narrative review

The objectives of this narrative review are to update readers on the current state-of-the-art regarding diverse approaches for the treatment of pain, global symptoms, or adequate relief in irritable bowel syndrome (IBS). The article appraises medications, dietary interventions including low fermentable oligosaccharides, disaccharides, and monosaccharides and polyols (FODMAP) diet, fecal microbial transplantation (FMT), electrical approaches, and behavioral therapies including cognitive behavioral therapy (CBT), gut-directed hypnotherapy (GDH), mindfulness, and open-label placebo. Current evidence demonstrates only modest benefit in global IBS symptoms and pain relief. A future approach that identifies pathophysiological mechanisms of IBS through validated biomarkers has the potential to individualize treatment of patients rather than sequential therapeutic trial and error approaches.

Efficacy of oral fecal microbiota transplantation in recurrent bowel disease: A protocol for systematic review and meta-analysis

BACKGROUND

Recurrent bowel disease (RBD) refers to the chronic, recurrent intestinal diseases, including recurrent Clostridium Difficile Infection (rCDI), inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), etc., these diseases have similar clinical characteristics, that is, abdominal pain, diarrhea, repeated attacks, prolonged recovery, etc. Clinically, there are relevant reports on the use of oral capsule fecal microbiota transplantation (oFMT) to treat RBD. However, both the advantages and disadvantages of clinical efficacy have been reported; there are some contradictions, the study sample size is too small, and the purpose of this systematic review was to evaluate the efficacy and safety of oral capsule fecal microbiota transplantation in the treatment of RBD.

METHODS

This systematic review will include articles identified through electronic searches of the PubMed, EMbase, and Cochrane Library. From inception to July 1, 2022. Two reviewers will independently search the database to conduct data extraction and assessment of study quality. Based on heterogeneity tests, data will be integrated using fixed or random effect models. RevMan V.5.4 will be used for data analysis. The results are expressed as the risk ratio of dichotomous data and the mean difference of continuous data.

RESULTS

We analyzed the clinical remission or cure rate, IBS-SSS, quality of life, anxiety, depression, total adverse effects, and total severe adverse effects (TSAE) in patients with RBD.

CONCLUSION

This systematic review evaluated the efficacy and safety of oFMT in the treatment of RBD to provide more comprehensive evidence.

Current and Future Therapeutic Options for Irritable Bowel Syndrome with Diarrhea and Functional Diarrhea

Irritable bowel syndrome with diarrhea and functional diarrhea are disorders of gut-brain interaction presenting with chronic diarrhea; they have significant impact on quality of life. The two conditions may exist as a continuum and their treatment may overlap. Response to first-line therapy with antispasmodics and anti-diarrheal agents is variable, leaving several patients with suboptimal symptom control and need for alternative therapeutic options. Our aim was to discuss current pharmacologic options and explore alternative therapeutic approaches and future perspectives for symptom management in irritable bowel syndrome with diarrhea and functional diarrhea. We conducted a search of PubMed, Cochrane, clinicaltrial.gov, major meeting abstracts for publications on current, alternative, and emerging drugs for irritable bowel syndrome with diarrhea and functional diarrhea. Currently approved therapeutic options for patients with first-line refractory irritable bowel syndrome with diarrhea and functional diarrhea include serotonin-3 receptor antagonists, eluxadoline and rifaximin. Despite their proven efficacy, cost and availability worldwide impact their utilization. One-third of patients with disorders of gut-brain interaction with diarrhea have bile acid diarrhea and may benefit from drugs targeting bile acid synthesis and excretion. Further understanding of underlying pathophysiology of irritable bowel syndrome with diarrhea and functional diarrhea related to bile acid metabolism, gastrointestinal transit, and microbiome has led to evaluation of novel therapeutic approaches, including fecal microbiota transplantation and enterobacterial "crapsules". These opportunities to treat disorders of gut-brain interaction with diarrhea should be followed with formal studies utilizing large samples of well-characterized patients at baseline and validated response outcomes as endpoints for regulatory approval.

Pre-Antibiotic Treatment Followed by Prolonged Repeated Faecal Microbiota Transplantation Improves Symptoms and Quality of Life in Patients with Irritable Bowel Syndrome: An Observational Australian Clinical Experience

Background. The use of faecal microbiota transplantation (FMT) in irritable bowel syndrome (IBS) has frequently failed to induce long-term symptomatic improvement. The use of multiple FMT infusions is one proposed mechanism through which the efficacy of FMT can be amplified. Aims. To evaluate the safety and efficacy of a novel six-month FMT treatment protocol in IBS. Methods. Patients diagnosed with IBS confirmed by Rome IV Criteria were recruited for single-centre, single-arm, prospective clinical observational study. Participants received one colonoscopically delivered FMT followed by 36 rectal enemas across a six-month period. Validated abdominal symptoms and Short-Form (SF-36) Quality of Life (QOL) questionnaires were collected at baseline, week-12, week-24, and week-56, respectively. Wilcoxon matched-pairs signed-rank tests were conducted to compare differences in abdominal symptom and SF-36 QOL scores over the follow-up timepoints. Statistical significance was set at 5%. Results. Sixty participants diagnosed with IBS [IBS-constipation ( $n=27$ ), IBS-diarrhoea ( $n=18$ ), and IBS-mixed ( $n=15$ )] received the six-month FMT treatment. IBS symptom severity reduction was achieved in up to 61% of respondents at week-12, 64% of respondents at week-24, and maintained in up to 75% of respondents at week-52. Long-term reduction in symptom severity was associated with an increase in QOL, achieved in up to 64% of respondents at week-52 when compared to baseline. Adverse events were experienced in 28% of participants, though they were both transient and mild in nature. Conclusions. Six-month sustained FMT appears to be both safe and effective in the short- and long-term alleviation of IBS associated symptoms as well as improving participant QOL.

Current perspectives on irritable bowel syndrome: a narrative review

The pathophysiology of irritable bowel syndrome (IBS) has not yet been fully elucidated. We reviewed articles addressing IBS that have been published in the last 2 years and selected papers related to IBS pathophysiology and treatment. Studies of intestinal bacteria, low-grade mucosal inflammation, and increased mucosal permeability—factors involved in the pathophysiology of IBS—have been conducted. In addition, the involvement of intestinal bacteria in IBS pathology has been clarified; many studies of treatments related to intestinal bacteria have been reported. Moreover, several studies address the effect on IBS of antidepressants and psychotherapy through the brain–gut axis. The contents of these papers are described in this narrative review.

Fecal Microbiota Transplantation for Patients With Irritable Bowel Syndrome: A Meta-Analysis of Randomized Controlled Trials

Background:

Gut microbiota has been identified as an imbalance in patients with irritable bowel syndrome (IBS). Fecal microbiota transplantation (FMT) is a novel method to restore microbiota and treat IBS patients.

Objective

To conduct a meta-analysis and estimate the efficacy and safety of FMT for the treatment of IBS patients with subgroup analyses to explore the most effective way of FMT for IBS.

Methods

All eligible studies were searched from PubMed, Embase, Web of Science, and the Cochrane Library through multiple search strategies. Data were extracted from studies comprising the following criteria: double-blind, randomized controlled trials (RCTs) that compared the efficacy of FMT with placebo for adult patients (≥18 years old) with IBS. A meta-analysis was performed to evaluate the summary relative risk (RR) and 95% confidence intervals (CIs).

Results

A total of seven RCTs comprising 489 subjects were eligible for this meta-analysis. Pooled data showed no significant improvement of global IBS symptoms in patients with FMT compared with placebo (RR = 1.34; 95% CI 0.75–2.41, p = 0.32). A significant heterogeneity was observed among the studies (I² = 83%, p < 0.00001). There was no significant evidence of funnel plot asymmetry (Egger's test, p = 0.719; Begg's test, p = 1.000), indicating no existence of publication bias. Subgroup analyses revealed that FMT operated by invasive routes, including gastroscope, colonoscope, and nasojejunal tube, significantly improved global IBS symptoms (RR = 1.96; 95% CI 1.23–3.11, p = 0.004) with heterogeneity (I² = 57%, p = 0.06) and an NNT of 3 (95% CI 2–14). However, FMT delivered via oral capsules showed a negative impact on patients with IBS (RR = 0.56; 95% CI 0.33–0.96, p = 0.03) with a low heterogeneity (I² = 39%, p = 0.2) and an NNH of 3 (95% CI 2–37).

Conclusion

The current evidence from RCTs with all routes of FMT does not show significant global improvement in patients with IBS. However, FMT operated by invasive routes significantly improved global IBS symptoms.

Review article: current and future treatment approaches for pain in IBS

BACKGROUND

Abdominal pain is a core symptom of IBS and a primary driver of care seeking. Visceral hypersensitivity is a key pathophysiological mechanism and therapeutic target for pain in IBS, with components of peripheral and central sensitisation and psychological factors.

AIM

To review current and future treatment approaches specifically for the pain component of IBS.

METHODS

Pubmed search terms included combinations of irritable bowel, pain, visceral hypersensitivity, novel, new, emerging, future and advances.

RESULTS

Established non-pharmacological treatments for IBS pain include the low FODMAP diet, probiotics and psychological interventions, especially hypnotherapy. Tricyclics remain the best evidenced pharmacological approach with GCC agonists, tenapanor, lubiprostone, eluxadoline and 5HT3 antagonists second line according to patient characteristics and availability. Less well-evidenced current options include anti-spasmodics, peppermint oil, SSRIs, SNRIs, alpha 2 delta ligands, melatonin and histamine antagonists. Patients are vulnerable to iatrogenesis and harmful approaches to be avoided include opioids and unwarranted surgical interventions. For severe pain, the concept of augmentation with combined gut-brain neuromodulators and psychotherapy in a multi-disciplinary setting is considered. A plethora of molecular targets and ligands are emerging from pre-clinical studies, together with early clinical evidence for a range of pharmacological, dietary, neurostimulation and novel psychological treatment delivery methods which are reviewed. The history of such emerging approaches, however, merits both caution and optimism in equal measure.

CONCLUSIONS

Despite good in-roads and emerging options, the management of abdominal pain remains one of the biggest challenges and research priorities for patients with IBS.

Effect of Low FODMAPs Diet on Irritable Bowel Syndromes: A Systematic Review and Meta-Analysis of Clinical Trials

We conducted a meta-analysis exploring the effect of a low fermentable oligo-, di-, monosaccharides, and polyols diet (LFD) on the overall symptoms, quality of life, and stool habits of irritable bowel syndrome (IBS) patients. The meta-analysis was performed using a random-effects method. The effect size was presented as weighted standardized mean difference (SMD) and 95% confidence interval (CI). Subgroup analyses were conducted to determine the potential effects of covariates on the outcome. Twenty-two papers were included. The LFD group showed a moderate reduction in symptom severity and a slight improvement in quality of life compared to the control group (SMD, −0.53 and 0.24; 95% CI, −0.68, −0.38 and 0.02, 0.47, respectively). IBS symptom improvement was consistent between subgroups stratified according to proportions of female patients, study durations, IBS subtypes, assessment methods, and control interventions. Three studies regarding stool habits change in IBS-D patients showed a significant decrease in stool frequency (mean differences [MD], −5.56/week; 95% CI, −7.40, −3.72) and a significant improvement in stool consistency (MD, −0.86; 95% CI, −1.52, −0.19) in the LFD group compared to the control group. This is the most updated meta-analysis including studies that adopted diverse control interventions such as dietary interventions, supplementation, habitual diets, and lifestyle changes.