Systematic review with meta-analysis: the efficacy of faecal microbiota transplantation for the treatment of recurrent and refractory Clostridium difficile infection

Five years of fecal microbiota transplantation - an update of the Israeli experience

AIM

To evaluate and describe the efficacy of fecal microbiota transplantation (FMT) for Clostridium difficile infection (CDI) in a national Israeli cohort.

METHODS

All patients who received FMT for recurrent (recurrence within 8 wk of the previous treatment) or refractory CDI from 2013 through 2017 in all the five medical centers in Israel currently performing FMT were included. Stool donors were screened according to the Israeli Ministry of Health guidelines. Clinical and laboratory data of patients were collected from patients’ medical files, and they included indications for FMT, risk factors for CDI and disease severity. Primary outcome was FMT success (at least 2 mo free of CDI-related diarrhea post-FMT). Secondary outcomes included initial response to FMT (cessation of diarrhea within 7 d) and recurrence at 6 mo.

RESULTS

There were 111 FMTs for CDI, with a median age of 70 years [interquartile range (IQR): 53-82], and 42% (47) males. Fifty patients (45%) were treated via the lower gastrointestinal (LGI, represented only by colonoscopy) route, 37 (33%) via capsules, and 24 (22%) via the upper gastrointestinal (UGI) route. The overall success rate was 87.4% (97 patients), with no significant difference between routes of administration (P = 0.338). In the univariant analysis, FMT success correlated with milder disease (P = 0.01), ambulatory setting (P < 0.05) and lower Charlson comorbidity score (P < 0.05). In the multivariant analysis, only severe CDI [odd ratio (OR) = 0.14, P < 0.05] and inpatient FMT (OR = 0.19, P < 0.05) were each independently inversely related to FMT success. There were 35 (32%) patients younger than 60 years of age, and 14 (40%) of them had a background of inflammatory bowel disease.

CONCLUSION

FMT is a safe and effective treatment for CDI, with capsules emerging as a successful and well-tolerated route. Severe CDI is less likely to respond to FMT.

Faecal microbiota transplantation alters gut microbiota in patients with irritable bowel syndrome: results from a randomised, double-blind placebo-controlled study

OBJECTIVE

IBS is associated with an intestinal dysbiosis and faecal microbiota transplantation (FMT) has been hypothesised to have a positive effect in patients with IBS. We performed a randomised, double-blind placebo-controlled trial to investigate if FMT resulted in an altered gut microbiota and improvement in clinical outcome in patients with IBS.

DESIGN

We performed this study in 52 adult patients with moderate-to-severe IBS. At the screening visit, clinical history and symptoms were assessed and faecal samples were collected. Patients were randomised to FMT or placebo capsules for 12 days and followed for 6 months. Study visits were performed at baseline, 1, 3 and 6 months, where patients were asked to register their symptoms using the IBS-severity scoring system (IBS-SSS) and IBS-specific quality of life (IBS-QoL). Prior to each visit, faecal samples were collected.

RESULTS

A significant difference in improvement in IBS-SSS score was observed 3 months after treatment (p=0.012) favouring placebo. This was similar for IBS-QoL data after 3 months (p=0.003) favouring placebo. Patients receiving FMT capsules had an increase in faecal microbial biodiversity while placebos did not.

CONCLUSION

In this randomised double-blinded placebo-controlled study, we found that FMT changed gut microbiota in patients with IBS. But patients in the placebo group experienced greater symptom relief compared with the FMT group after 3 months. Altering the gut microbiota is not enough to obtain clinical improvement in IBS. However, different study designs and larger studies are required to examine the role of FMT in IBS.

TRIAL REGISTRATION NUMBER

NCT02788071.

Impact of Amoxicillin-Clavulanate followed by Autologous Fecal Microbiota Transplantation on Fecal Microbiome Structure and Metabolic Potential

The spread of multidrug resistance among pathogenic organisms threatens the efficacy of antimicrobial treatment options. The human gut serves as a reservoir for many drug-resistant organisms and their resistance genes, and perturbation of the gut microbiome by antimicrobial exposure can open metabolic niches to resistant pathogens. Once established in the gut, antimicrobial-resistant bacteria can persist even after antimicrobial exposure ceases. Strategies to prevent multidrug-resistant organism (MDRO) infections are scarce, but autologous fecal microbiota transplantation (autoFMT) may limit gastrointestinal MDRO expansion. AutoFMT involves banking one’s feces during a healthy state for later use in restoring gut microbiota following perturbation. This pilot study evaluated the effect of amoxicillin-clavulanic acid (Amox-Clav) exposure and autoFMT on gastrointestinal microbiome taxonomic composition, resistance gene content, and metabolic capacity. Importantly, we found that metabolic capacity was perturbed even in cases where gross phylogeny remained unchanged and that autoFMT was safe and well tolerated.

Strategies to prevent multidrug-resistant organism (MDRO) infections are scarce, but autologous fecal microbiota transplantation (autoFMT) may limit gastrointestinal MDRO expansion. AutoFMT involves banking one’s feces during a healthy state for later use in restoring gut microbiota following perturbation. This pilot study evaluated the effect of autoFMT on gastrointestinal microbiome taxonomic composition, resistance gene content, and metabolic capacity after exposure to amoxicillin-clavulanic acid (Amox-Clav). Ten healthy participants were enrolled. All received 5 days of Amox-Clav. Half were randomized to autoFMT, derived from stool collected pre-antimicrobial exposure, by enema, and half to saline enema. Participants submitted stool samples pre- and post-Amox-Clav and enema and during a 90-day follow-up period. Shotgun metagenomic sequencing revealed taxonomic composition, resistance gene content, and metabolic capacity. Amox-Clav significantly altered gut taxonomic composition in all participants (n = 10, P < 0.01); however, only three participants exhibited major changes at the phylum level following exposure. In the cohort as a whole, beta-lactamase genes were enriched following Amox-Clav (P < 0.05), and predicted metabolic capacity was significantly altered (P < 0.01). Species composition, metabolic capacity, and beta-lactamase abundance returned to pre-antimicrobial exposure state 7 days after either autoFMT or saline enema (P > 0.05, compared to enrollment). Alterations to microbial metabolic capacity occurred following antimicrobial exposure even in participants without substantial taxonomic disruption, potentially creating open niches for pathogen colonization. Our findings suggest that metabolic potential is an important consideration for complete assessment of antimicrobial impact on the microbiome. AutoFMT was well tolerated and may have contributed to phylogenetic recovery. (This study has been registered at ClinicalTrials.gov under identifier NCT02046525.)

IMPORTANCE The spread of multidrug resistance among pathogenic organisms threatens the efficacy of antimicrobial treatment options. The human gut serves as a reservoir for many drug-resistant organisms and their resistance genes, and perturbation of the gut microbiome by antimicrobial exposure can open metabolic niches to resistant pathogens. Once established in the gut, antimicrobial-resistant bacteria can persist even after antimicrobial exposure ceases. Strategies to prevent multidrug-resistant organism (MDRO) infections are scarce, but autologous fecal microbiota transplantation (autoFMT) may limit gastrointestinal MDRO expansion. AutoFMT involves banking one’s feces during a healthy state for later use in restoring gut microbiota following perturbation. This pilot study evaluated the effect of amoxicillin-clavulanic acid (Amox-Clav) exposure and autoFMT on gastrointestinal microbiome taxonomic composition, resistance gene content, and metabolic capacity. Importantly, we found that metabolic capacity was perturbed even in cases where gross phylogeny remained unchanged and that autoFMT was safe and well tolerated.

Clinical Application and Potential of Fecal Microbiota Transplantation

Fecal microbiota transplantation (FMT) is a well-established treatment for recurrent Clostridioides difficile infection. FMT has become a more readily available and useful new treatment option as a result of stool banks. The current state of knowledge indicates that dysbiosis of the gut microbiota is implicated in several disorders in addition to C. difficile infection. Randomized controlled studies have shown FMT to be somewhat effective in treating ulcerative colitis, irritable bowel syndrome, and hepatic encephalopathy. In addition, FMT has been beneficial in treating several other conditions, such as the eradication of multidrug-resistant organisms and graft-versus-host disease. We expect that FMT will soon be implemented as a treatment strategy for several new indications, although further studies are needed.

Microbiome modulates intestinal homeostasis against inflammatory diseases

Eliminating prophylactic antibiotics in food animal production has exerted pressure on discovering antimicrobial alternatives (e.g. microbiome) to reduce elevated intestinal diseases. Intestinal tract is a complex ecosystem coupling host cells with microbiota. The microbiota and its metabolic activities and products are collectively called microbiome. Intestinal homeostasis is reached through dynamic and delicate crosstalk between host immunity and microbiome. However, this balance can be occasionally broken, which results in intestinal inflammatory diseases such as human Inflammatory Bowel Diseases, chicken necrotic enteritis, and swine postweaning diarrhea. In this review, we introduce the intestinal immune system, intestinal microbiome, and microbiome modulation of inflammation against intestinal diseases. The purpose of this review is to provide updated knowledge on host-microbe interaction and to promote using microbiome as new antimicrobial strategies to reduce intestinal diseases.

Safety and preliminary efficacy of orally administered lyophilized fecal microbiota product compared with frozen product given by enema for recurrent Clostridium difficile infection: A randomized clinical trial

Background

Fecal microbiota transplantation (FMT) via colonoscopy or enema has become a commonly used treatment of recurrent C. difficile infection (CDI).

Aims

To compare the safety and preliminary efficacy of orally administered lyophilized microbiota product compared with frozen product by enema.

Methods

In a single center, adults with ≥ 3 episodes of recurrent CDI were randomized to receive encapsulated lyophilized fecal microbiota from 100–200 g of donor feces (n = 31) or frozen FMT from 100 g of donor feces (n = 34) by enema. Safety during the three months post FMT was the primary study objective. Prevention of CDI recurrence during the 60 days after FMT was a secondary objective. Fecal microbiome changes were examined in first 39 subjects studied.

Results

Adverse experiences were commonly seen in equal frequency in both groups and did not appear to relate to the route of delivery of FMT. CDI recurrence was prevented in 26 of 31 (84%) subjects randomized to capsules and in 30 of 34 (88%) receiving FMT by enema (p = 0.76). Both products normalized fecal microbiota diversity while the lyophilized orally administered product was less effective in repleting Bacteroidia and Verrucomicrobia classes compared to frozen product via enema.

Conclusions

The route of delivery, oral or rectal, did not influence adverse experiences in FMT. In preliminary evaluation, both routes appeared to show equivalent efficacy, although the dose may need to be higher for lyophilized product. Spore-forming bacteria appear to be the most important engrafting organisms in FMT by the oral route using lyophilized product.

Trial registration

ClinicalTrials.gov NCT02449174

Comparing fecal microbiota transplantation to standard-of-care treatment for recurrent Clostridium difficile infection: a systematic review and meta-analysis

BACKGROUND

The use of fecal microbiota transplantation (FMT) as a treatment option for recurrent Clostridium difficile infection (rCDI) is well established. Various studies have used different forms and administration routes for FMT. We performed a systemic review and meta-analysis to update the clinical knowledge about different FMT modalities for curing rCDI compared with medical treatment (MT).

PATIENTS AND METHODS

We searched PubMed and Medline from inception through 10 May 2018 for randomized control trials (RCTs) comparing FMT (fresh or frozen) versus MT. We used Cochrane Collaboration's Risk of Bias tool to assess bias in the RCTs. We estimated odds ratio (OR) with 95% confidence interval (CI) for each outcome using a random effects model. P values of less than 0.05 were considered significant.

RESULTS

We included seven RCTs comprising a total of 543 patients with recurrent CDI. There was a nonsignificant trend toward resolution of diarrhea following a single fresh FMT infusion compared with frozen FMT and MT (OR=2.45, 95% CI=0.78-7.71, P=0.12, I=69%). Subgroup analysis of fresh FMT vs. frozen FMT showed no difference between the two groups (OR=2.13, 95% CI=0.22-20.41, P=0.51, I=61%). Frozen FMT infusion through upper route versus lower route showed no difference (OR=0.62, 95% CI=0.15-2.54, P=0.51, I=0%). There was a nonsignificant trend favoring multiple treatments with FMT versus multiple courses of MT (OR=3.68, 95% CI=0.74-18.22, P=0.11, I=0%).

CONCLUSION

FMT is a promising treatment modality for rCDI compared with MT alone. Different forms and routes of FMT administration seem to be equally efficacious. In future, more well-designed RCTs directed at homogenous FMT preparation and delivery methods are required to validate these findings.

The use of faecal microbiota transplant as treatment for recurrent or refractory Clostridium difficile infection and other potential indications: joint British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS) guidelines

Interest in the therapeutic potential of faecal microbiota transplant (FMT) has been increasing globally in recent years, particularly as a result of randomised studies in which it has been used as an intervention. The main focus of these studies has been the treatment of recurrent or refractory Clostridium difficile infection (CDI), but there is also an emerging evidence base regarding potential applications in non-CDI settings. The key clinical stakeholders for the provision and governance of FMT services in the UK have tended to be in two major specialty areas: gastroenterology and microbiology/infectious diseases. While the National Institute for Health and Care Excellence (NICE) guidance (2014) for use of FMT for recurrent or refractory CDI has become accepted in the UK, clear evidence-based UK guidelines for FMT have been lacking. This resulted in discussions between the British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS), and a joint BSG/HIS FMT working group was established. This guideline document is the culmination of that joint dialogue.

Fecal microbiota transplantation in recurrent Clostridium difficile infection: A retrospective single-center chart review

Background and Aim

Fecal microbiota transplantation (FMT) has been proposed as a treatment option for patients with recurrent Clostridium difficile (C. difficile) infection but remains a novel option. We examined if FMT is an effective means of treating recurrent C. difficile infection.

Methods

A retrospective review of 35 patients who underwent FMT was completed. Demographics and other variables, including the use of proton pump inhibitor therapy and history of inflammatory bowel disease, were collected.

Results

Twenty-five patients (71.4%) belonged to a high-risk population (working in a hospital setting, rehabilitation center, or nursing facility) and a total of 74.3% of patients (n = 26 patients) had no history of proton pump inhibitor use. Twenty-five patients (71.4%) had used metronidazole prior to transplantation, 35 patients (100%) had used vancomycin, and 7 patients (20%) had used fidaxomicin for prior infection. Four patients (11.4%) had used all three antibiotics during prior treatment. Of the eight patients who had a history of inflammatory bowel disease, six (75%) experienced resolution of symptoms after transplantation. A total of 30 patients (85.7%) had resolution of their symptoms 6-8 weeks' posttransplant, while 5 patients (14.3%) continued to have symptoms.

Conclusions

Our retrospective chart review supports that patients benefit from FMT in the setting of recurrent C. difficile infection.

Efficacy of different faecal microbiota transplantation protocols for Clostridium difficile infection: A systematic review and meta-analysis

BACKGROUND

Protocols for treating recurrent Clostridium difficile infection (rCDI) through faecal microbiota transplantation (FMT) are still not standardised. Our aim was to evaluate the efficacy of different FMT protocols for rCDI according to routes, number of infusions and infused material.

METHODS

MEDLINE, Embase, SCOPUS, Web of Science and the Cochrane Library were searched through 31 May 2017. Studies offering multiple infusions if a single infusion failed to cure rCDI were included. Data were combined through a random effects meta-analysis.

RESULTS

Fifteen studies (1150 subjects) were analysed. Multiple infusions increased efficacy rates overall (76% versus 93%) and in each route of delivery (duodenal delivery: 73% with single infusion versus 81% with multiple infusions; capsule: 80% versus 92%; colonoscopy: 78% versus 98% and enema: 56% versus 92%). Duodenal delivery and colonoscopy were associated, respectively, with lower efficacy rates (p = 0.039) and higher efficacy rates (p = 0.006) overall. Faecal amount ≤ 50 g (p = 0.006) and enema (p = 0.019) were associated with lower efficacy rates after a single infusion. The use of fresh or frozen faeces did not influence outcomes.

CONCLUSIONS

Routes, number of infusions and faecal dosage may influence efficacy rates of FMT for rCDI. These findings could help to optimise FMT protocols in clinical practice.

Faecal microbiota transplantation as a treatment for inflammatory bowel disease: a national survey of adult and paediatric gastroenterologists in the UK

BACKGROUND

Interest in the use of faecal microbiota transplantation (FMT) in inflammatory bowel disease (IBD) has increased following outcomes in patients with Clostridioides difficile infection (CDI). While research exploring clinician awareness and attitude towards the use of FMT in CDI has been carried out, data for IBD are currently lacking.

OBJECTIVE

To assess the perceptions of gastroenterologists and current practice relating to FMT as a treatment for IBD in the UK.

DESIGN

A web-based survey (Snap Survey software) was distributed through the British Society of Gastroenterology (BSG) and British Society of Paediatric Gastroenterology, Hepatology and Nutrition e-newsletters, and at the BSG Conference in June 2017.

RESULTS

61 respondents completed the survey including presubspecialty trainees, gastroenterology specialists, associate specialists and consultants. Most (95%; n=58) respondents stated that they had heard of FMT being used as a treatment for IBD prior to participating in the survey. Based on current evidence, 34% (n=21) of respondents would consider using FMT in patients with IBD, 26% (n=16) would not and 39% (n=24) were undecided. When asked to rank routes of delivery in terms of preference, nasogastric tube was the least preferred route (39%; n=24) and oral capsule was the most preferred route (34%; n=21).

CONCLUSIONS

A clear majority of UK gastroenterologists recognise FMT as a potential treatment for IBD; however, uptake is limited. A proportion of clinicians would consider FMT in IBD and the majority would consider entering patients into clinical trials. Future work should explore the utility and efficacy of oral FMT capsules in IBD.

Role of the Gut⁻Liver Axis in Driving Parenteral Nutrition-Associated Injury

For decades, parenteral nutrition (PN) has been a successful method for intravenous delivery of nutrition and remains an essential therapy for individuals with intolerance of enteral feedings or impaired gut function. Although the benefits of PN are evident, its use does not come without a significant risk of complications. For instance, parenteral nutrition-associated liver disease (PNALD)—a well-described cholestatic liver injury—and atrophic changes in the gut have both been described in patients receiving PN. Although several mechanisms for these changes have been postulated, data have revealed that the introduction of enteral nutrition may mitigate this injury. This observation has led to the hypothesis that gut-derived signals, originating in response to the presence of luminal contents, may contribute to a decrease in damage to the liver and gut. This review seeks to present the current knowledge regarding the modulation of what is known as the “gut–liver axis” and the gut-derived signals which play a role in PN-associated injury.

Fecal microbial transplantation: an update

PURPOSE OF REVIEW

The purpose of this article is to provide an update on recent developments in fecal microbiota transplantation (FMT) in the last year.

RECENT FINDINGS

Although FMT is an accepted treatment for recurrent Clostridium difficile infection (CDI), recently it is also gaining acceptance for the treatment of refractory CDI. FMT is showing promise in ulcerative colitis and is experimental in many other conditions. The optimal practical aspects to enhance the success of FMT are still being established.

SUMMARY

The implication of current research is that the indications of FMT may be extended to other conditions in the future.

Rebuilding the Gut Microbiota Ecosystem

A microbial ecosystem in which bacteria no longer live in a mutualistic association is called dysbiotic. Gut microbiota dysbiosis is a condition related with the pathogenesis of intestinal illnesses (irritable bowel syndrome, celiac disease, and inflammatory bowel disease) and extra-intestinal illnesses (obesity, metabolic disorder, cardiovascular syndrome, allergy, and asthma). Dysbiosis status has been related to various important pathologies, and many therapeutic strategies aimed at restoring the balance of the intestinal ecosystem have been implemented. These strategies include the administration of probiotics, prebiotics, and synbiotics; phage therapy; fecal transplantation; bacterial consortium transplantation; and a still poorly investigated approach based on predatory bacteria. This review discusses the various aspects of these strategies to counteract intestinal dysbiosis.

Randomised clinical trial: faecal microbiota transplantation by colonoscopy plus vancomycin for the treatment of severe refractory Clostridium difficile infection-single versus multiple infusions

BACKGROUND

Faecal microbiota transplantation (FMT) is a highly effective treatment against recurrent Clostridium difficile infection. Far less evidence exists on the efficacy of FMT in treating severe Clostridium difficile infection refractory to antibiotics.

AIM

To compare the efficacy of two FMT-based protocols associated with vancomycin in curing subjects with severe Clostridium difficile infection refractory to antibiotics.

METHODS

Subjects with severe Clostridium difficile infection refractory to antibiotics were randomly assigned to one of the two following treatment arms: (1) FMT-S, including a single faecal infusion via colonoscopy followed by a 14-day vancomycin course, (2) FMT-M, including multiple faecal infusions plus a 14-day vancomycin course. In the FMT-M group, all subjects received at least two infusions, while those with pseudomembranous colitis underwent further infusions until the disappearance of pseudomembranes. The primary outcome was the cure of refractory severe Clostridium difficile infection.

RESULTS

Fifty six subjects, 28 in each treatment arm, were enrolled. Twenty one patients in the FMT-S group and 28 patients in the FMT-M group were cured (75% vs 100%, respectively, both in per protocol and intention-to-treat analyses; P = 0.01). No serious adverse events associated with any of the two treatment protocols were observed.

CONCLUSIONS

A pseudomembrane-driven FMT protocol consisting of multiple faecal infusions and concomitant vancomycin was significantly more effective than a single faecal transplant followed by vancomycin in curing severe Clostridium difficile infection refractory to antibiotics. Clinical-Trials.gov registration number: NCT03427229.

Mechanistic Insights in the Success of Fecal Microbiota Transplants for the Treatment of Clostridium difficile Infections

Fecal microbiota transplantation has proven to be an effective treatment for infections with the gram-positive enteropathogen Clostridium difficile. Despite its effectiveness, the exact mechanisms that underlie its success are largely unclear. In this review, we highlight the pleiotropic effectors that are transferred during fecal microbiota transfer and relate this to the C. difficile lifecycle. In doing so, we show that it is likely that multiple factors contribute to the elimination of symptoms of C. difficile infections after fecal microbiota transplantation.

The role of gut microbiota in Clostridium difficile infection

Clostridium difficile infection has emerged as a major health problem. Because it is a spore-forming microorganism, C. difficile is difficult to eradicate and recurrences of the infection are frequent. The strong association of CDI with prior use of antibiotics led to the recognition that disturbances in the gut microbiota apparently plays a central role in CDI. Except for antibiotics, several other risk factors for CDI have been recognised, such as advanced age and use of proton pump inhibitors. The common characteristic of these factors is that they are associated with changes in the composition of gut microbiota. Data from human studies have shown that the presence of C. difficile, either as a colonizer or as a pathogen, is associated with reduced microbiota diversity. C. difficile infection per se seems to be associated with changes in the representation of specific microbial populations (e.g. taxa) which either may act protectively against C. difficile colonization of the gut or may increase susceptibility for C. difficile infection. Therapeutic gut microbiota manipulation can be achieved by faecal microbiota transplantation, which is highly effective for the treatment of CDI.

Scaling Safe Access to Fecal Microbiota Transplantation: Past, Present, and Future

PURPOSE OF REVIEW

Universal stool banks (USBs) have emerged as a potential model for scaling access to fecal microbiota transplantation (FMT) for Clostridium difficile infection (CDI). In this review, we outline the historical barriers constraining access to FMT, the evidence on methods and outcomes of USBs, and potential future directions for expanding access.

RECENT FINDINGS

Key historical barriers to FMT access include regulatory uncertainty, operational complexity of sourcing screened donor material, and logistical challenges of delivering fresh treatment preparations. USBs have demonstrated that FMT can be delivered safely at scale by centralizing donor selection, material processing, and safety monitoring. More evidence is needed to optimize USB methods, including for donor screening, material processing, and novel delivery modalities. USBs have catalyzed broad access to FMT in North America and Europe. Future directions include developing evidence regarding oral preparations, harmonizing guidelines, disseminating best practice protocols, establishing long-term safety profiles, and expanding access to geographic areas of unmet need.

Comparison of Different Strategies for Providing Fecal Microbiota Transplantation to Treat Patients with Recurrent Clostridium difficile Infection in Two English Hospitals: A Review

Fecal microbiota transplant (FMT) has emerged as a highly efficacious treatment for difficult cases of refractory and/or recurrent Clostridium difficile infection (CDI). There have been many well-conducted randomized controlled trials and thousands of patients reported in case series that describe success rates of approximately 90% following one or more FMT. Although the exact mechanisms of FMT have yet to be fully elucidated, replacement or restoration of a 'normal' microbiota (or at least a microbiota resembling those who have never had CDI) appears to have a positive effect on the gut dysbiosis that is thought to exist in these patients. Furthermore, despite being aesthetically unappealing, this 'ultimate probiotic' is a particularly attractive solution to a difficult problem that avoids repeated courses of antibiotics. The lack of clarity about the exact mechanism of action and the 'active ingredient' of FMT (e.g., individual or communities of bacteria, bacteriophage, or bioactive molecules such as bile acids) has hindered the ability to produce a standardized and well-characterized FMT product. There is no standard method to produce material for FMT, and there are a multitude of factors that can vary between institutions that offer this therapy. Only a few studies have directly compared clinical efficacy in groups of patients who have been treated with FMT prepared differently (e.g., fresh vs. frozen) or administered by different route (e.g., by nasojejunal tube, colonoscopy or by oral administration of encapsulated product). More of these studies should be undertaken to clarify the superiority or otherwise of these variables. This review describes the methods and protocols that two English NHS hospitals independently adopted over the same time period to provide FMT for patients with recurrent CDI. There are several fundamental differences in the methods used, including selection and testing of donors, procedures for preparation and storage of material, and route of administration. These methods are described in detail in this review highlighting differing practice. Despite these significant methodological variations, clinical outcomes in terms of cure rate appear to be remarkably similar for both FMT providers. Although both hospitals have treated only modest numbers of patients, these findings suggest that many of the described differences may not be critical factors in influencing the success of the procedure. As FMT is increasingly being proposed for a number of conditions other than CDI, harmonization of methods and techniques may be more critical to the success of FMT, and thus it will be important to standardize these as far as practically possible.

The long-term effects of faecal microbiota transplantation for gastrointestinal symptoms and general health in patients with recurrent Clostridium difficile infection

BACKGROUND

Faecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection. In short-term the treatment has been shown to be safe, however, there are no large, long-term follow-up studies looking into the potential adverse effects.

AIM

To analyse the long-term effect of FMT treatment in patients with recurrent C. difficile infection and to compare the outcome to antibiotic treated patients.

METHODS

Altogether 84 patients of which 45 received a FMT treatment and 39 served as controls receiving antibiotics for the infection were followed on average for 3.8 years. Their recovery and medical status was evaluated using a retrospective questionnaire, determining their quality of life, gastrointestinal symptoms and new diseases potentially related to the FMT.

RESULTS

There was no difference in the incidence of severe diseases (inflammatory bowel disease, cancer, autoimmune disease, allergy, neurological diseases) between the patient groups. In addition, weight gain did not differ between treatment groups. The FMT treated patients reported that their bowel habits improved significantly faster, they had less irregular bowel function and less symptoms of upper GI-tract when compared to the patients treated with antibiotics. Significantly more patients in FMT-group reported that their mental health improved after the treatment. The willingness to receive FMT treatment for potential new C. difficile infection was significantly higher in both treatment groups compared to other treatment options.

CONCLUSION

Our study highlights that FMT is a durable, safe and acceptable treatment option for patients with recurrent C. difficile infection also in long term, and it shows potential benefits over antimicrobial treatment.

The taxonomic composition of the donor intestinal microbiota is a major factor influencing the efficacy of faecal microbiota transplantation in therapy refractory ulcerative colitis

BACKGROUND

Faecal microbiota transplantation is an experimental approach for the treatment of patients with ulcerative colitis. Although there is growing evidence that faecal microbiota transplantation is effective in this disease, factors affecting its response are unknown.

AIMS

To establish a faecal microbiota transplantation treatment protocol in ulcerative colitis patients, and to investigate which patient or donor factors are responsible for the treatment success.

METHODS

This is an open controlled trial of repeated faecal microbiota transplantation after antibiotic pre-treatment (FMT-group, n = 17) vs antibiotic pre-treatment only (AB-group, n = 10) in 27 therapy refractory ulcerative colitis patients over 90 days. Faecal samples of donors and patients were analysed by 16SrRNA gene-based microbiota analysis.

RESULTS

In the FMT-group, 10/17 (59%) of patients showed a response and 4/17 (24%) a remission to faecal microbiota transplantation. Response to faecal microbiota transplantation was mainly influenced by the taxonomic composition of the donor's microbiota. Stool of donors with a high bacterial richness (observed species remission 946 ± 93 vs no response 797 ± 181 at 15367 rps) and a high relative abundance of Akkermansia muciniphila (3.3 ± 3.1% vs 0.1 ± 0.2%), unclassified Ruminococcaceae (13.8 ± 5.0% vs 7.5 ± 3.7%), and Ruminococcus spp. (4.9 ± 3.5% vs 1.0 ± 0.7%) were more likely to induce remission. In contrast antibiotic treatment alone (AB-group) was poorly tolerated, probably because of a sustained decrease of intestinal microbial richness.

CONCLUSIONS

The taxonomic composition of the donor's intestinal microbiota is a major factor influencing the efficacy of faecal microbiota transplantation in ulcerative colitis patients. The design of specific microbial preparation might lead to new treatments for ulcerative colitis.

Gut microbiota in the pathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is a chronic and relapsing inflammatory disorder of the intestine. Although its incidence is increasing globally, the precise etiology remains unclear and a cure for IBD has yet to be discovered. The most accepted hypothesis of IBD pathogenesis is that complex interactions between genetics, environmental factors, and the host immune system lead to aberrant immune responses and chronic intestinal inflammation. The human gut harbors a complex and abundant aggregation of microbes, collectively referred to as the gut microbiota. The gut microbiota has physiological functions associated with nutrition, the immune system, and defense of the host. Recent advances in next-generation sequencing technology have identified alteration of the composition and function of the gut microbiota, which is referred to as dysbiosis, in IBD. Clinical and experimental data suggest dysbiosis may play a pivotal role in the pathogenesis of IBD. This review is focused on the physiological function of the gut microbiota and the association between the gut microbiota and pathogenesis in IBD. In addition, we review the therapeutic options for manipulating the altered gut microbiota, such as probiotics and fecal microbiota transplantation.

Randomized clinical trial to evaluate the effect of fecal microbiota transplant for initial Clostridium difficile infection in intestinal microbiome

OBJECTIVE

The aim of this study was to evaluate the impact of fecal donor-unrelated donor mix (FMT-FURM) transplantation as first-line therapy for C. difficile infection (CDI) in intestinal microbiome.

METHODS

We designed an open, two-arm pilot study with oral vancomycin (250mg every 6 h for 10-14 days) or FMT-FURM as treatments for the first CDI episode in hospitalized adult patients in Hospital Universitario "Dr. Jose Eleuterio Gonzalez". Patients were randomized by a closed envelope method in a 1: 1 ratio to either oral vancomycin or FMT-FURM. CDI resolution was considered when there was a reduction on the Bristol scale of at least 2 points, a reduction of at least 50% in the number of bowel movements, absence of fever, and resolution of abdominal pain (at least two criteria). From each patient, a fecal sample was obtained at days 0, 3, and 7 after treatment. Specimens were cultured to isolate C. difficile, and isolates were characterized by PCR. Susceptibility testing of isolates was performed using the agar dilution method. Fecal samples and FMT-FURM were analyzed by 16S rRNA sequencing.

RESULTS

We included 19 patients; 10 in the vancomycin arm and 9 in the FMT-FURM arm. However, one of the patients in the vancomycin arm and two patients in the FMT-FURM arm were eliminated. Symptoms resolved in 8/9 patients (88.9%) in the vancomycin group, while symptoms resolved in 4/7 patients (57.1%) after the first FMT-FURM dose (P = 0.26) and in 5/7 patients (71.4%) after the second dose (P = 0.55). During the study, no adverse effects attributable to FMT-FURM were observed in patients. Twelve isolates were recovered, most isolates carried tcdB, tcdA, cdtA, and cdtB, with an 18-bp deletion in tcdC. All isolates were resistant to ciprofloxacin and moxifloxacin but susceptible to metronidazole, linezolid, fidaxomicin, and tetracycline. In the FMT-FURM group, the bacterial composition was dominated by Firmicutes, Bacteroidetes, and Proteobacteria at all-time points and the microbiota were remarkably stable over time. The vancomycin group showed a very different pattern of the microbial composition when comparing to the FMT-FURM group over time.

CONCLUSION

The results of this preliminary study showed that FMT-FURM for initial CDI is associated with specific bacterial communities that do not resemble the donors' sample.

Different Substrate Preferences Help Closely Related Bacteria To Coexist in the Gut

Many factors shape the ability of different microbes to coexist in microbial communities. In the human gut, dietary and host-derived nutrients largely drive microbial community structure. How gut microbes with very similar nutrient profiles are able to coexist over time within the same host is not fully understood. Tuncil et al. (mBio 8:e01068-17, 2017, https://doi.org/10.1128/mBio.01068-17) explored glycan prioritization in two closely related human gut bacteria, Bacteroides ovatus and Bacteroides thetaiotaomicron, on complex glycan mixtures that both organisms can degrade. Determining depletion of the individual glycans over time in pure cultures and cocultures revealed that the bacteria seem to have hardwired differences in their preferences for different glycans which likely contribute to their stable coexistence. The researchers also established that gene expression changes of the corresponding polysaccharide utilization loci did not always mirror glycan depletion, which highlights that additional regulatory mechanisms must be present.