Background & Aims Robust evidence for most licensed Crohn's disease therapies is lacking for perianal fistula outcomes due to a lack of dedicated clinical trials. This study aimed to use a Bayesian framework to determine the efficacy of medical therapies for perianal fistulizing Crohn's disease (PFCD).Methods A formal prior elicitation exercise was conducted by a group of 11 gastroenterologists and 5 statisticians. Consensus priors were developed leveraging both existing published data and clinical expertise, to determine one-year fistula remission rates for medical treatments with 5 different mechanisms of action (anti-TNF, anti-integrin, anti-IL-12/23, anti-IL-23, and JAK inhibitor). Consensus priors on efficacy of each treatment were determined relative to an elicited consensus prior for placebo control.Results Consensus priors were obtained for the likelihood of fistula remission at 1 year. The prior mean, together with a 90% prior credible interval, of the one-year fistula remission rate was 0.22 (0.05, 0.46) for placebo, 0.58 (0.09, 0.96) for intravenous infliximab, 0.39 (0.06, 0.82) for adalimumab, 0.53 (0.09, 0.93) for subcutaneous infliximab, 0.24 (0.03, 0.60) for intravenous vedolizumab, 0.44 (0.05, 0.90) for upadacitinib, 0.34 (0.04, 0.77) for ustekinumab, and 0.36 (0.04, 0.82) for anti-IL-23 specific agents. Oral upadacitinib and subcutaneous infliximab demonstrated the highest probability for efficacy, alongside intravenous infliximab.Conclusions We have conducted the first Bayesian prior elicitation exercise in inflammatory bowel disease. The generated priors could be used to enhance the design and analysis of clinical trials in PFCD by improving estimation of treatment efficacy, minimizing sample sizes, and potentially reducing the need for placebo control arms.

OBJECTIVE:To provide an updated, evidence-based European Crohn's and Colitis Organisation [ECCO]-European Society for Paediatric Gastroenterology, Hepatology and Nutrition [ESPGHAN] guideline for the management, monitoring, and long-term care of pediatric Crohn's disease [CD]. METHODS:A multidisciplinary panel of 27 experts followed ECCO Standard Operating Procedures for guideline development. A systematic review of studies published between January 2018 and October 2024, with targeted updates through June 2025, was conducted across MEDLINE, EMBASE, and Cochrane Central. Evidence was graded using the Oxford Centre for Evidence-Based Medicine levels. Draft statements underwent two Delphi voting rounds involving the guideline panel, ECCO National Representatives, and an international sounding board; statements achieving ≥80% agreement were accepted. RESULTS:This guideline provides updated recommendations across major domains of pediatric CD care, including risk stratification, treatment targets, induction and maintenance strategies, nutritional therapies, therapeutic drug monitoring, and the roles of imaging and endoscopy. High-risk patients should start anti-TNF therapy as first-line treatment, with proactive and reactive therapeutic drug monitoring to enhance efficacy. For low-risk luminal disease, exclusive enteral nutrition or the Crohn's Disease Exclusion Diet with partial enteral nutrition are preferred induction options. Long-term management emphasizes achieving endoscopic remission, normal growth, improved quality of life, and reduction of bowel damage. This guideline also reviews emerging advanced therapies, including biologics and small molecules, which are increasingly used in practice but generally not yet approved for pediatric CD, to inform clinicians about their potential role. CONCLUSIONS:This updated ECCO-ESPGHAN guideline integrates new pediatric evidence with contemporary adult data and treat-to-target principles, providing practical recommendations to support personalized, multidisciplinary, and proactive management aimed at improving long-term outcomes in pediatric CD.

BACKGROUND:Neutralizing autoantibodies against interleukin-10 can result in a phenocopy of monogenic defects of interleukin-10 signaling in children and may be associated with inflammatory bowel disease (IBD). The allele HLA-DRB1*01:03 is the strongest genetic risk factor for ulcerative colitis. METHODS:We used a cellular interleukin-10 reporter assay and a confirmatory competitive enzyme-linked immunosorbent assay to assess neutralizing interleukin-10 autoantibodies in serum samples obtained from patients with IBD in the Oxford and U.K. IBD BioResource cohorts and from persons without IBD (controls). An in vitro cytokine-release bioassay was performed in a subgroup of patients to assess interleukin-10, interleukin-23, interleukin-1β, tumor necrosis factor, and interleukin-6. We performed HLA association analysis using imputation and high-resolution sequencing. RESULTS:Interleukin-10-neutralizing autoantibodies were detected in 173 of 4909 patients with IBD (3.5%; 95% confidence interval [CI], 3.0 to 4.1) and in none of 1006 controls (P<0.001). High anti-interleukin-10 activity in serum was associated with a reduction in detectable interleukin-10 and with an exaggerated proinflammatory cytokine response, consistent with functional neutralization of interleukin-10 signaling. Anti-interleukin-10 seropositivity was strongly associated with HLA-DRB1*01:03 on the basis of imputed data from the Oxford cohort (odds ratio, 50.0; 95% CI, 16.4 to 152.3; P = 6.14×10-12) and the U.K. IBD BioResource cohort (odds ratio, 24.7; 95% CI, 14.5 to 42.1; P = 6.20×10-32) and in a high-resolution sequencing analysis of data from the Oxford cohort (odds ratio, 29.5; 95% CI, 12.2 to 71.1; P = 4.85×10-14). CONCLUSIONS:Neutralizing interleukin-10 autoantibodies were present in a subgroup of patients with IBD and were strongly associated with HLA-DRB1*01:03. (Funded by the National Institute for Health and Care Research and others.).

BACKGROUND AND AIMS:Evidence from rheumatology supports a within-class treatment switch for JAK-inhibitors (JAKi), but data in ulcerative colitis (UC) remain limited. We aimed to assess the effectiveness and safety of initiating a second JAKi in patients with UC previously treated with another JAKi. METHODS:We conducted a multicenter retrospective study, including patients with UC starting a second JAKi after prior JAKi exposure. The primary endpoint was Week 12 steroid-free clinical remission (SFCR-rectal bleeding subscore = 0, stool frequency subscore ≤ 1, and no steroids). RESULTS:We included 243 patients (median follow-up: 38 [21-57] weeks). At Weeks 12, 26, and 52, SFCR was achieved in 116/243 (48%), 120/243 (49%), and 69/243 (28%), respectively. Secondary loss of response to the first JAKi was associated with higher SFCR at Week 12 compared to primary failure (odds ratio [OR] = 1.92, 95% confidence interval [CI] = 1.11-3.30, P = 0.02). Higher baseline disease activity (OR = 0.68, 95% CI = 0.68-0.55, P < 0.01) and steroid use (OR = 0.23, 95% CI = 0.13-0.42, P < 0.01) had lower odds of Week 12 SFCR. Endoscopic remission occurred in 22/243 (9%) (<Week 26) and 27/243 (11%) (26-78 weeks), and endoscopic improvement in 53/243 (22%) and 45/243 (19%), respectively. Sixty-seven (28%) patients discontinued the second JAKi, mostly due to primary (36/67) or secondary failure (22/67). Sixty-six adverse events (mostly acne and infections) occurred in 56 (23%) patients, without major thromboembolic or cardiovascular events. CONCLUSION:Treatment with a second JAKi is effective and safe in patients with UC already exposed to JAKi. Primary failure to a first JAKi and steroid use at initiation of the second JAKi might reduce the likelihood of success with the second JAKi.

BACKGROUND:Interleukin-10 (IL-10) is an essential regulator of intestinal immune homeostasis. Neutralising autoantibodies against IL-10 (anti-IL-10) have been identified in children and also adult patients with IBD. Positivity for anti-IL-10 autoantibodies was associated with carriage of HLA-DRB1*01:03 allele. OBJECTIVE:To determine the prevalence of anti-IL-10 in paediatric IBD and assess the associated clinical phenotype. DESIGN:We conducted a cross-sectional multicentre study across paediatric IBD cohorts from four countries. Anti-IL-10 antibodies were investigated in serum and plasma from paediatric patients with IBD (mean age of IBD onset 11.2±3.8 years). IL-10-neutralisation capacity was confirmed by functional IL-10 reporter assay, competitive ELISA and cytokine release assay. Clinical data were analysed to evaluate disease phenotype and treatment outcomes, with comparison with matched controls. HLA-DRB1*01:03 analysis was performed. RESULTS:Anti-IL-10 positivity was identified in 26/1045 paediatric patients with IBD (2.5%) (Crohn's disease n=6, UC n=19, IBD unclassified n=1; IBD diagnosis age of 13±3 years). Anti-IL-10 autoantibodies were of the IgG class and amplified pro-inflammatory cytokine responses in vitro. Anti-IL-10-positive patients exhibited more severe disease compared with matched controls, including an increased prevalence of difficult-to-treat disease (23% vs 6%, p=0.03), higher rate of acute severe UC (26% vs 6%; p=0.038) and higher rates of colectomy (27% vs 6%, p=0.01). Eighty percent (16/20) of anti-IL-10-positive patients with available HLA data carried the HLA-DRB1*01:03 allele, compared with 1.5% in the anti-IL-10-negative group. CONCLUSION:Anti-IL-10 autoantibodies are present in a subgroup of paediatric patients with IBD and are associated with difficult-to-treat disease.

BACKGROUND:Reproduction is a fundamental aspect of life. This study aimed to provide an international overview of gastroenterologists' approaches to managing inflammatory bowel disease (IBD) during preconception, pregnancy, lactation, and postpartum. METHODS:An anonymous 75-question survey was distributed to gastroenterologists in 36 countries, including European countries, the United States of America, Latin American countries, Australia, and New Zealand, focusing on clinical practices for managing pregnancy and breastfeeding in IBD patients. RESULTS:A total of 856 gastroenterologists participated, 61% were IBD specialists. In pregnant patients in remission, participants stated they would discontinue IBD therapy as follows: 19% for thiopurines, 41% for anti-TNF, 37% for vedolizumab, 31% for ustekinumab, and 96% for small molecules. Many gastroenterologists avoided initiating oral or rectal budesonide, anti-TNF, vedolizumab, or ustekinumab during disease flares. Despite existing safety concerns, one-third of gastroenterologists reported initiating thiopurines to manage disease flares during pregnancy. Only 50% of gastroenterologists had specialized follow-up programs for pregnant patients with IBD in remission. Thirteen percent of gastroenterologists believed that all drugs were safe during breastfeeding. For vaccinations, about 20% advised against non-live vaccines, and 50% avoided live-vaccines during the first 12 months for infants exposed to anti-TNF in utero. Few gastroenterologists had referral pathways to IBD-specialized obstetricians or paediatricians. CONCLUSION:Our international survey suggests that management of IBD during pregnancy, lactation, and postpartum remains suboptimal, even among gastroenterologists specifically dedicated to IBD. Urgent educational efforts are needed to address these issues and improve care.

Acute severe colitis (ASC) is a relatively frequent manifestation in children with ulcerative colitis and one of the few emergencies in paediatric gastroenterology. A standardized proactive approach based on tight monitoring and timely medical and surgical interventions may improve patients' outcomes. We aimed to update the previous ASC guidelines using detailed recommendations and practice points, based on a systematic review of the literature and consensus of experts. These guidelines update is a joint effort of the European Society of Paediatric Gastroenterology, Hepatology and Nutrition and the European Crohn's and Colitis Organization. A systematic search was performed in Pubmed Ovid Medline, Embase and Cochrane databases using 13 predefined PICO (patient, intervention, comparison, outcomes) based questions and 30 non-PICO based questions. Grading methodology was based on the Oxford Centre for Evidence-Based Medicine-Levels of evidence. The questions were addressed by working subgroups following an iterative consensus voting process, including three online voting meetings and one face-to-face meeting. A total of 36 recommendations and 72 practice points were endorsed with a consensus rate of at least 88% for all statements, regarding initial evaluation, monitoring, medical and surgical treatment of ASC in children. Several topics have been revised since the previous 2018 guidelines and differ from corresponding published adult guidelines. These guidelines present a comprehensive overview of the management of ASC in children, offering practical recommendations and practice points aiming to standardize clinical and surgical treatment and improve outcomes of this severe scenario.

In response to recent advancements in inflammatory bowel disease (IBD) management, the British Society of Gastroenterology (BSG) Clinical Services and Standards Committee (CSSC) has commissioned the BSG IBD section to update its guidelines, last revised in 2019. These updated guidelines aim to complement the IBD standards and promote the use of the national primary care diagnostic pathway for lower gastrointestinal symptoms to enhance diagnostic accuracy and timeliness. Formulated through a systematic and transparent process, this document reflects a consensus of best practices based on current evidence. The guideline, while developed primarily for the UK, is structured to support IBD management internationally. It is endorsed by the BSG executive board and CSSC without external commercial funding, with involvement primarily supported through professional roles in public institutions and the National Health Service (NHS). Methodological revisions since the prior guidelines have enhanced rigor in technical review and development, with methodology details published independently following peer review. In developing the recommendations, 89 clinical experts and stakeholders participated in an online survey, identifying primary outcomes, such as clinical and endoscopic remission, as well as adverse event metrics, all stratified by clinically relevant effect sizes. These guidelines are intended to support clinical decision-making but are not prescriptive, recognizing that individual clinical scenarios may warrant tailored approaches. Further research may inform future revisions as new evidence emerges.

OBJECTIVES:Despite advances in the management of ambulatory paediatric ulcerative colitis (UC), challenges remain as many patients are refractory to therapy and some require colectomy. The aim of these guidelines is to provide an update on optimal care for UC through detailed recommendations and practice points. METHODS:These guidelines are an update to those published in 2018 and are a joint effort of the Paediatric IBD Porto group of European Society of Paediatric Gastroenterology, Hepatology and Nutrition and the European Crohn's and Colitis Organisation. An extensive literature search with subsequent evidence appraisal using the Oxford methodology was performed, followed by three online voting sessions and a consensus face-to-face meeting. Thirty-nine recommendations and 77 practice points were endorsed by the 25 experts with at least an 84% consensus rate. RESULTS:Robust evidence-based recommendations and detailed practice points are provided. In addition to reemphasising and updating the role of more 'traditional' UC therapies, these guidelines outline optimising the use of antitumour necrosis factor therapies and integrating newer biologics and small molecules, as well as supportive therapy, to improve outcomes and provide an updated management algorithm. Measurement and monitoring tools and decision aids are provided, and additional aspects, including nutritional support, extraintestinal manifestations, pouchitis, inflammatory bowel disease-unclassified and patient support, are discussed. Some aspects, including surgery and thromboprophylaxis, are covered in the acute severe UC guidelines. CONCLUSIONS:These guidelines serve as an aid in managing children with UC through a combination of evidence-based recommendations and more practical practice points in the ambulatory setting.

Retinoic acid, produced by intestinal dendritic cells (DCs), promotes T cell trafficking to the intestinal mucosa by upregulating α4β7 integrin and inhibiting the generation of cutaneous leukocyte Ag (CLA) required for skin entry. In the present study, we report that activation of human naive CD4 T cells in an APC-free system generates cells expressing α4β7 alone; in contrast, activation by intestinal DCs that produce retinoic acid and induce high levels of α4β7 also results in CLA expression, generating CLA+α4β7+ "dual tropic" cells, with both gut and skin trafficking potential, that also express high levels of α4β1 integrin. DC generation of CLA+α4β7+ T cells is associated with upregulation of FUT7, a fucosyltransferase involved in CLA generation; requires cell contact; and is enhanced by IL-12/IL-23. The blood CD4+ T cell population contains CLA+α4β7+ cells, which are significantly enriched for cells capable of IFN-γ, IL-17, and TNF-α production compared with conventional CLA-α4β7+ cells. Dual tropic lymphocytes are increased in intestinal tissue from patients with Crohn's disease, and single-cell RNA-sequencing analysis identifies a transcriptionally distinct cluster of FUT7-expressing cells present only in inflamed tissue; expression of genes associated with cell proliferation suggests that these cells are undergoing local activation. The expression of multiple trafficking molecules by CLA+α4β7+ T cells can enable their recruitment by alternative pathways to both skin and gut; they may contribute to both intestinal and cutaneous manifestations of inflammatory bowel disease.

This article is the second in a series of two publications on the European Crohn's and Colitis Organisation [ECCO] evidence-based consensus on the management of Crohn's disease. The first article covers medical management; the present article addresses surgical management, including preoperative aspects and drug management before surgery. It also provides technical advice for a variety of common clinical situations. Both articles together represent the evidence-based recommendations of the ECCO for Crohn's disease and an update of prior ECCO Guidelines.

BACKGROUND AND AIMS:No effective therapeutic intervention exists for intestinal fibrosis in Crohn's disease [CD]. We characterized fibroblast subtypes, epigenetic and metabolic changes, and signalling pathways in CD fibrosis to inform future therapeutic strategies. METHODS:We undertook immunohistochemistry, metabolic, signalling pathway and epigenetic [Transposase-Accessible Chromatin using sequencing] analyses associated with collagen production in CCD-18Co intestinal fibroblasts and primary fibroblasts isolated from stricturing [SCD] and non-stricturing [NSCD] CD small intestine. SCD/NSCD fibroblasts were cultured with TGFβ and valproic acid [VPA]. RESULTS:Stricturing CD was characterized by distinct histone deacetylase [HDAC] expression profiles, particularly HDAC1, HDAC2, and HDAC7. As a proxy for HDAC activity, reduced numbers of H3K27ac+ cells were found in SCD compared to NSCD sections. Primary fibroblasts had increased extracellular lactate [increased glycolytic activity] and intracellular hydroxyproline [increased collagen production] in SCD compared to NSCD cultures. The metabolic effect of TGFβ stimulation was reversed by the HDAC inhibitor VPA. SCD fibroblasts appeared 'metabolically primed' and responded more strongly to both TGFβ and VPA. Treatment with VPA revealed TGFβ-dependent and TGFβ-independent Collagen-I production in CCD-18Co cells and primary fibroblasts. VPA altered the epigenetic landscape with reduced chromatin accessibility at the COL1A1 and COL1A2 promoters. CONCLUSIONS:Increased HDAC expression profiles, H3K27ac hypoacetylation, a significant glycolytic phenotype and metabolic priming characterize SCD-derived as compared to NSCD fibroblasts. Our results reveal a novel epigenetic component to Collagen-I regulation and TGFβ-mediated CD fibrosis. HDAC inhibitor therapy may 'reset' the epigenetic changes associated with fibrosis.