Obesity-related cognitive decline is linked to gut microbiota dysbiosis, with emerging evidence suggesting that dietary interventions may ameliorate cognitive impairment via gut-brain axis modulation. The role of microglial cells in this process remains underexplored.

Patients with inflammatory bowel disease (IBD) remain at increased risk for colorectal cancer and death from colorectal cancer compared with the general population despite improvements in inflammation control with advanced therapies, colonoscopic surveillance and reductions in environmental risk factors. This guideline update from 2010 for colorectal surveillance of patients over 16 years with colonic inflammatory bowel disease was developed by stakeholders representing UK physicians, endoscopists, surgeons, specialist nurses and patients with GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodological support.An a priori protocol was published describing the approach to three levels of statement: GRADE recommendations, good practice statements or expert opinion statements. A systematic review of 7599 publications, with appraisal and GRADE analysis of trials and network meta-analysis, where appropriate, was performed. Risk thresholding guided GRADE judgements.We made 73 statements for the delivery of an IBD colorectal surveillance service, including outcome standards for service and endoscopist audit, and the importance of shared decision-making with patients.Core areas include: risk of colorectal cancer, IBD-related post-colonoscopy colorectal cancer; service organisation and supporting patient concordance; starting and stopping surveillance, who should or should not receive surveillance; risk stratification, including web-based multivariate risk calculation of surveillance intervals; colonoscopic modalities, bowel preparation, biomarkers and artificial intelligence aided detection; chemoprevention; the role of non-conventional dysplasia, serrated lesions and non-targeted biopsies; management of dysplasia, both endoscopic and surgical, and the structure and role of the multidisciplinary team in IBD dysplasia management; training in IBD colonoscopic surveillance, sustainability (green endoscopy), cost-effectiveness and patient experience. Sixteen research priorities are suggested.

Determining optimal management of colorectal polyps in patients with limited life expectancy of under 10 years can be difficult, due to challenges balancing an uncertain natural history of polyp progression to symptomatic malignancy versus the increased risk and consequences of polypectomy complications.

There is no effective drug treatment for the organ failure (OF) caused by severe acute pancreatitis (SAP).

Faecal microbiota transplantation (FMT) has emerged as a transformative therapy for Clostridioides difficile infections and shows promise for various GI and systemic diseases. However, the poor patient acceptability and accessibility of 'conventional' FMT, typically administered via colonoscopies or enemas, hinders its widespread clinical adoption, particularly for chronic conditions. Oral administration of FMT (OralFMT) overcomes these limitations, yet faces distinct challenges, including a significant capsule burden, palatability concerns and poor microbial viability during gastric transit. This review provides a comprehensive analysis of emerging strategies that aim to advance OralFMT by: (1) refining processing technologies (eg, lyophilisation) that enable manufacturing of low-volume FMT formulations for reducing capsule burden and (2) developing delivery technologies that improve organoleptic acceptability and safeguard the microbiota for targeted colonic release. These advancements present opportunities for OralFMT to expand its therapeutic scope, beyond C. difficile infections, towards chronic GI conditions requiring frequent dosing regimens. While this review primarily focuses on optimising OralFMT delivery, it is important to contextualise these advancements within the broader shift towards defined microbial consortia. Live biotherapeutic products (LBPs) offer an alternative approach, yet the interplay between OralFMT and LBPs in clinical practice remains unresolved. We postulate that continued innovation in OralFMT and LBPs via a multidisciplinary approach can further increase therapeutic efficacy and scalability by enabling disease site targeting, co-delivery of therapeutic compounds and overcoming colonisation resistance. Realising these goals positions OralFMT as a cornerstone of personalised care across a range of diseases rooted in microbiome health.

Inflammatory bowel diseases (IBDs) are characterised by dysbiosis and a leaky gut. The NADPH oxidase dual oxidase 2 (DUOX2) is upregulated in patients with IBD, yet its role in driving the disease remains unclear.

IBD is a chronic inflammatory condition driven by complex genetic and immune interactions, yet preclinical models often fail to fully recapitulate all aspects of the human disease. A systematic comparison of commonly used IBD models is essential to identify conserved molecular mechanisms and improve translational relevance.

Fibrolamellar carcinoma (FLC), a rare and fatal liver cancer lacking effective drug therapy, is driven by the DNAJ-PKAc fusion oncoprotein. However, the underlying mechanism of DNAJ-PKAc's role in FLC tumour growth remains enigmatic.

Precision cancer risk stratification for gastric cancer is urgently needed for the growing number of healthy people after Helicobacter pylori eradication. The epimutation burden in non-malignant tissues has been associated with cancer risk in multiple cross-sectional studies.

Pouchitis, defined as inflammation of the ileal pouch, is the most common complication following restorative proctocolectomy for refractory ulcerative colitis. Antibiotics remain the first line of therapy for pouchitis, but the majority of patients develop subsequent episodes and some are refractory to antibiotic therapy. This highlights the need for more effective treatment options and points to a more complex pathophysiology beyond the role of th pouch microbiome, similar to what is seen in inflammatory bowel disease. In this review, we outline the putative mechanisms of pouchitis, including genetic predisposition, microbiome alterations, dysfunction of the intestinal barrier and the immune system and review the available animal models of pouchitis. In addition, we introduce the concept of pouchitis as a possible transmural disease and discuss the potential role of non-immune cells, including stromal cells, in perpetuating inflammation and intestinal barrier dysfunction. We discuss future directions, implications for novel therapies and propose novel multicellular disease models that can better capture the complexity of pouchitis pathogenesis.

Colonoscopy is among the standard tests for colorectal cancer (CRC) screening. However, uptake varies, and alternatives such as colon capsule endoscopy (CCE) are available. The uptake and detection rate of clinically significant neoplasia with CCE, compared with colonoscopy, remain unclear in this setting.

Injured or reactive biliary epithelial cells participate in most chronic liver injuries in a process referred to as ductular reaction, which involves multicellular interactions with marked local infiltration of macrophages and fibrogenic cell activation. The direct roles of biliary epithelial cells in shaping their cellular niche remain unknown.

A rise in paediatric cases of acute hepatitis of unknown origin (AHUO) was observed in 2022, some requiring liver transplantation. A link to adeno-associated virus 2 infection and CD4+T-cell mediated disease was reported in cohorts in the UK and USA but does not explain all cases.

Recommendations for the first postpolypectomy surveillance colonoscopy (SC1), based on stratifying postpolypectomy colorectal cancer (CRC) risk, are well established. Limited data inform recommendations for surveillance beyond SC1.

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease which, if untreated, often leads to cirrhosis, liver failure and death. The last British Society of Gastroenterology (BSG) guideline for the management of AIH was published in 2011. Since then, our understanding of AIH has advanced in many areas. This update to the previous guideline was commissioned by the BSG and developed by a multidisciplinary group. The aim of this guideline is to review and summarise the current evidence, in order to inform and guide diagnosis and management of patients with AIH and its variant syndromes. The main focus is on AIH in adults, but the guidelines should also be relevant to older children and adolescents.

Development of diffuse-type gastric cancer (DGC) starts with intramucosal lesions that are primarily composed of differentiated, non-proliferative signet ring cells (SRCs). These indolent lesions can advance into highly proliferative and metastatic tumours, which requires suppression of DGC cell differentiation.

In primary care, National Institute for Health and Care Excellence suspected cancer guidelines recommend measuring faecal haemoglobin (f-Hb) if colorectal cancer (CRC) is suspected, with a referral threshold of ≥10 µg Hb/g faeces defining a 3% risk, but most have a normal colonoscopy.