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 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.

The Editors of the Journals have agreed that joint publication of the article is justified to ensure dissemination of the guidance to all relevant healthcare professionals.

ObjectiveFaecal microbiota transplant (FMT) effectively treats recurrent Clostridioides difficile infection (rCDI), but its mechanisms of action remain poorly defined. Certain bile acids affect C. difficile germination or vegetative growth. We hypothesised that loss of gut microbiota-derived bile salt hydrolases (BSHs) predisposes to CDI by perturbing gut bile metabolism, and that BSH restitution is a key mediator of FMT’s efficacy in treating the condition.DesignUsing stool collected from patients and donors pre-FMT/post-FMT for rCDI, we performed 16S rRNA gene sequencing, ultra performance liquid chromatography mass spectrometry (UPLC-MS) bile acid profiling, BSH activity measurement, and qPCR of bsh/baiCD genes involved in bile metabolism. Human data were validated in C. difficile batch cultures and a C57BL/6 mouse model of rCDI.ResultsFrom metataxonomics, pre-FMT stool demonstrated a reduced proportion of BSH-producing bacterial species compared with donors/post-FMT. Pre-FMT stool was enriched in taurocholic acid (TCA, a potent C. difficile germinant); TCA levels negatively correlated with key bacterial genera containing BSH-producing organisms. Post-FMT samples demonstrated recovered BSH activity and bsh/baiCD gene copy number compared with pretreatment (p<0.05). In batch cultures, supernatant from engineered bsh-expressing E. coli and naturally BSH-producing organisms (Bacteroides ovatus, Collinsella aerofaciens, Bacteroides vulgatus and Blautia obeum) reduced TCA-mediated C. difficile germination relative to culture supernatant of wild-type (BSH-negative) E. coli. C. difficile total viable counts were ~70% reduced in an rCDI mouse model after administration of E. coli expressing highly active BSH relative to mice administered BSH-negative E. coli (p<0.05).ConclusionRestoration of gut BSH functionality contributes to the efficacy of FMT in treating rCDI.

Specific urinary metabolites related to gut microbial metabolism differ between CD patients, UC patients, and controls. The emerging technique of urinary metabolic profiling with multivariate analysis was able to distinguish these cohorts.

Fecal metabolites are being increasingly studied to unravel the host-gut microbial metabolic interactions. However, there are currently no guidelines for fecal sample collection and storage based on a systematic evaluation of the effect of time, storage temperature, storage duration and sampling strategy. Here we derive an optimized protocol for fecal sample handling with the aim of maximizing metabolic stability and minimizing sample degradation. Samples obtained from five healthy individuals were analyzed to assess topographical homogeneity of feces, and to evaluate storage duration-, temperature-and freeze-thaw cycle-induced metabolic changes in crude stool and fecal water using a 1 H NMR spectroscopy-based metabolic profiling approach. Inter-individual variation was much greater than that attributable to storage conditions. Individual stool samples were found to be heterogeneous and spot sampling resulted in a high degree of metabolic variation. Crude fecal samples were remarkably unstable over time and exhibited distinct metabolic profiles at different storage temperatures. Microbial fermentation was the dominant driver in time-related changes observed in fecal samples stored at room temperature and this fermentative process was reduced when stored at 4°C. Crude fecal samples frozen at -20°C manifested elevated amino acids and nicotinate and depleted short chain fatty acids compared to crude fecal control samples. The relative concentrations of branched-chain and aromatic amino acids significantly increased in the freeze-thawed crude fecal samples, suggesting a release of microbial intracellular contents. The metabolic profiles of fecal water samples were more stable compared to crude samples. Our recommendation is that intact fecal samples should be collected, kept at 4°C or on ice during transportation, and extracted ideally within 1 h of collection, or a maximum of 24 h. Fecal water samples should be extracted from a representative amount (~15 g) of homogenized stool sample, aliquoted and stored at < -20°C, avoiding further freeze-thaw cycles.Metabolic profiling of biofluids and tissues generates data on a wide range of metabolites and provides extensive metabolic information on multiple biological processes in complex superorganisms such as mammals. Although urine and blood are often used to investigate systemic responses of animals and humans to various environmental stimuli or therapeutic interventions 1 , the search for disease biomarkers in fecal samples and studies on host-microbial interactions have intensified over the last decade. The human intestinal tract harbors >100 trillion microbial cells 2 and these microbes exert their influences on the human host primarily by metabolic signaling and therefore optimized methodologies for the study of microbial metabolic footprint is crucial to this field. Mounting evidence shows that the microbial composition and its collective metabolic activity profoundly impacts host physiology and modulates the disease risk of the host 3 . To investigate th...

Background The effects that therapies for inflammatory bowel disease (IBD) have on immune responses to SARS-CoV-2 vaccination are not yet fully known. Therefore, we sought to determine whether COVID-19 vaccineinduced antibody responses were altered in patients with IBD on commonly used immunosuppressive drugs. Methods In this multicentre, prospective, case-control study (VIP), we recruited adults with IBD treated with one of six different immunosuppressive treatment regimens (thiopurines, infliximab, a thiopurine plus infliximab, ustekinumab, vedolizumab, or tofacitinib) and healthy control participants from nine centres in the UK. Eligible participants were aged 18 years or older and had received two doses of COVID-19 vaccines (either ChAdOx1 nCoV-19 [Oxford-AstraZeneca], BNT162b2 [Pfizer-BioNTech], or mRNA1273 [Moderna]) 6-12 weeks apart (according to scheduling adopted in the UK). We measured antibody responses 53-92 days after a second vaccine dose using the Roche Elecsys Anti-SARS-CoV-2 spike electrochemiluminescence immunoassay. The primary outcome was anti-SARS-CoV-2 spike protein antibody concentrations in participants without previous SARS-CoV-2 infection, adjusted by age and vaccine type, and was analysed by use of multivariable linear regression models. This study is registered in the ISRCTN Registry, ISRCTN13495664, and is ongoing. Findings Between May 31 and Nov 24, 2021, we recruited 483 participants, including patients with IBD being treated with thiopurines (n=78), infliximab (n=63), a thiopurine plus infliximab (n=72), ustekinumab (n=57), vedolizumab (n=62), or tofacitinib (n=30), and 121 healthy controls. We included 370 participants without evidence of previous infection in our primary analysis. Geometric mean anti-SARS-CoV-2 spike protein antibody concentrations were significantly lower in patients treated with infliximab (156•8 U/mL [geometric SD 5•7]; p<0•0001), infliximab plus thiopurine (111•1 U/mL [5•7]; p<0•0001), or tofacitinib (429•5 U/mL [3•1]; p=0•0012) compared with controls (1578•3 U/mL [3•7]). There were no significant differences in antibody concentrations between patients treated with thiopurine monotherapy (1019•8 U/mL [4•3]; p=0•74), ustekinumab (582•4 U/mL [4•6]; p=0•11), or vedolizumab (954•0 U/mL [4•1]; p=0•50) and healthy controls. In multivariable modelling, lower anti-SARS-CoV-2 spike protein antibody concentrations were independently associated with infliximab (geometric mean ratio 0•12, 95% CI 0•08-0•17; p<0•0001) and tofacitinib (0•43, 0•23-0•81; p=0•0095), but not with ustekinumab (0•69, 0•41-1•19; p=0•18), thiopurines (0•89, 0•64-1•24; p=0•50), or vedolizumab (1•16, 0•74-1•83; p=0•51). mRNA vaccines (3•68, 2•80-4•84; p<0•0001; vs adenovirus vector vaccines) were independently associated with higher antibody concentrations and older age per decade (0•79, 0•72-0•87; p<0•0001) with lower antibody concentrations. Interpretation For patients with IBD, the immunogenicity of COVID-19 vaccines varies according to immunosuppressive drug exposure, and is attenuated in recipie...

Background Fecal microbiota transplantation is an emerging therapeutic option, particularly for the treatment of recurrent Clostridioides difficile infection. Stool banks that organise recruitment and screening of feces donors are being embedded within the regulatory frameworks described in the European Union Tissue and Cells Directive and the technical guide to the quality and safety of tissue and cells for human application, published by the European Council. Objective Several European and international consensus statements concerning fecal microbiota transplantation have been issued. While these documents provide overall guidance, we aim to provide a detailed description of all processes that relate to the collection, handling and clinical application of human donor stool in this document. Methods Collaborative subgroups of experts on stool banking drafted concepts for all domains pertaining to stool banking. During a working group meeting in the United European Gastroenterology Week 2019 in Barcelona, these concepts were discussed and finalised to be included in our overall guidance document about fecal microbiota transplantation. Results A guidance document for all domains pertaining to stool banking was created. This document includes standard operating manuals for several processes involved with stool banking, such as handling of donor material, storage and donor screening. Conclusion The implementation of fecal microbiota transplantation by stool banks in concordance with our guidance document will enable quality assurance and guarantee the availability of donor feces preparations for patients.

Antibiotic-associated diarrhoea is among the most common adverse events related to antibiotic use. Most cases are mild, but infection causes a spectrum of disease, ranging from occasional diarrhoea to colitis, toxic megacolon, and potentially death. Recent developments in our understanding of the biology of the gut microbiota have provided new insights into the pathogenesis of these conditions, and have revealed a role for manipulation of the gut microbiota as a novel therapeutic approach. This review will give an overview of the assessment of these conditions, before focusing on the rapidly developing area of their treatment.