Background: Nutritional support is very important in the treatment of Paediatric Inflammatory Bowel Disease (IBD). The role of the Mediterranean Diet (MD) has been understudied in children with IBD. The aims of this study were to assess the dietary intakes of IBD children in comparison with healthy controls (HCs), their adherence to MD; and the relationship between inflammation and dietary behaviors. Methods: Paediatric IBD patients in clinical remission and HCs were enrolled. The nutritional status and adherence to the Mediterranean Diet was evaluated through a 3-day food diary and the Mediterranean Diet Quality Index for Children and Adolescents (KIDMED). Results: The analysis of food diaries showed a significantly higher kilocalorie intake in IBD patients compared to HCs (p = 0.012), an increase in carbohydrates (p = 0.015) and in protein intake (p = 0.024). Both IBD and HCs have an intermediate adherence to MD. The comparison between Crohn’s disease (CD) and Ulcerative colitis (UC) patients showed significant difference in protein intake in CD patients (p = 0.047), as well as for vitamin D (p = 0.044) and iron intake (p = 0.023). Interestingly; in IBD patients we found a significant association between adherence to MD and a low level of fecal calprotectin (p = 0.027). Conclusion: Children with IBD in remission have a sub-optimal food intake compared to HCs. MD seems to correlate to decreased intestinal inflammation.

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.

Objective: Epigenetic mechanisms, including DNA methylation (DNAm), have been proposed to play a key role in Crohn’s disease (CD) pathogenesis. However, the specific cell types and pathways affected as well as their potential impact on disease phenotype and outcome remain unknown. We set out to investigate the role of intestinal epithelial DNAm in CD pathogenesis. Design: We generated 312 intestinal epithelial organoids (IEOs) from mucosal biopsies of 168 patients with CD (n=72), UC (n=23) and healthy controls (n=73). We performed genome-wide molecular profiling including DNAm, bulk as well as single-cell RNA sequencing. Organoids were subjected to gene editing and the functional consequences of DNAm changes evaluated using an organoid-lymphocyte coculture and a nucleotide-binding oligomerisation domain, leucine-rich repeat and CARD domain containing 5 (NLRC5) dextran sulphate sodium (DSS) colitis knock-out mouse model. Results: We identified highly stable, CD-associated loss of DNAm at major histocompatibility complex (MHC) class 1 loci including NLRC5 and cognate gene upregulation. Single-cell RNA sequencing of primary mucosal tissue and IEOs confirmed the role of NLRC5 as transcriptional transactivator in the intestinal epithelium. Increased mucosal MHC-I and NLRC5 expression in adult and paediatric patients with CD was validated in additional cohorts and the functional role of MHC-I highlighted by demonstrating a relative protection from DSS-mediated mucosal inflammation in NLRC5-deficient mice. MHC-I DNAm in IEOs showed a significant correlation with CD disease phenotype and outcomes. Application of machine learning approaches enabled the development of a disease prognostic epigenetic molecular signature. Conclusions: Our study has identified epigenetically regulated intestinal epithelial MHC-I as a novel mechanism in CD pathogenesis.

Functional constipation is a common problem in childhood and has a great impact on social, physical, and emotional functioning of affected children and their caregivers. No organic cause of the constipation can be found in approximately 95% of children, defining the “so-called” chronic functional constipation. Its prevalence has been reported to range from 0.7 to 29.6%, with a median of 12%. The diagnosis of functional constipation is exclusively clinical based on the pediatric diagnostic Rome criteria for functional gastrointestinal disorders and does not routinely require laboratory and/or radiological investigations. In case of alarm signs and symptoms that may suggest organic diseases, further investigations can be required. The therapeutic management is based on non-pharmacological and pharmacological approaches. Education, demystification of constipation and reward-based toilet training represent the cornerstones of nonpharmacological management. Disimpaction, maintenance treatment and weaning of medication are all elements of pharmacological treatment. Osmotic laxatives, mainly polyethylene glycol (PEG), are considered the first-choice laxative for both disimpaction and maintenance treatment. The aim of this review is to provide pediatric gastroenterologists with a practical tool to support the clinical and therapeutic management of children and adolescents affected by chronic functional constipation.