Search

Inflammatory bowel disease (IBD) chronicity results from memory T helper cell (Tmem) reactivation. Identifying patient-specific immunotypes is crucial for tailored treatment. We conducted a comprehensive study integrating circulating immune proteins and circulating Tmem, with intestinal tissue histology and mRNA analysis, in therapy-naïve pediatric IBD (Crohn's disease, CD: n = 62; ulcerative colitis, UC: n = 20; age-matched controls n = 43), and after 10-12 weeks' induction therapy. At diagnosis, plasma protein profiles unveiled two UC and three CD clusters with distinct disease courses. UC patients displayed unchanged circulating Tmem, while CD exhibited increased frequencies of gut-homing ex-Th17, known for high IFN-γ production. UC#2 had elevated Th17/neutrophil-pathway-related proteins and severe disease, with higher endoscopic and histological damage and Th17/neutrophil infiltration. Although both UC#1 and UC#2 responded to therapy, UC#2 required earlier immunomodulation. CD#3 had lower plasma protein concentrations, especially IFN-γ pathway proteins, fewer gut-homing ex-Th17 and clinically milder disease, confirmed by intestinal gene expression. CD#1 and CD#2 had comparably high Th1-related immune profiles, but CD#1 exhibited higher concentrations of proteins previously associated with poorer prognosis. Both CD clusters responded to induction therapy, with similar one-year outcomes. This study highlights feasibility of discriminating patient-specific immunotypes in IBD, advancing our understanding of immune pathogenesis, needed for tailored treatment strategies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

CD4 + memory T cell (T M ) reactivation drives chronicity in inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis. Defects driving loss of T M regulation likely differ between patients but remain undefined. In health, approximately 40 % of circulating gut-homing CD38 + T M express co-inhibitory receptor T-cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT). TIGIT + CD38 + T M have regulatory function while TIGIT neg CD38 + T M are enriched in IFN-γ-producing cells. We hypothesized TIGIT neg CD38 + T M are inflammatory and drive disease in a subgroup of IBD patients. We characterized TIGIT + CD38 + T M in a uniquely large cohort of pediatric IBD patients from time of diagnosis into adulthood. Circulating TIGIT neg CD38 + T M frequencies were higher in a subgroup of therapy-naïve CD patients with high plasma IFN-γ and a more severe disease course. TIGIT neg CD38 + T M were highly enriched in HLA-DR + and ex-Th17/Th1-like cells, high producers of IFN-γ. Cultures of healthy-adult-stimulated T M identified IL-12 as the only IBD-related inflammatory cytokine to drive the pathogenic ex-Th17-TIGIT neg CD38 + phenotype. Moreover, IL12RB2 mRNA expression was higher in TIGIT neg CD38 + T M than TIGIT + CD38 + T M , elevated in CD biopsies compared to controls, and correlated with severity of intestinal inflammation. Overall, we argue that in a subgroup of pediatric CD, increased IL-12 signaling drives reprogramming of Th17 to inflammatory Th1-like TIGIT neg CD38 + T M and causes more severe disease., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: FMR, NMC, JCE, and LdR are involved in industry-sponsored studies/investigator-initiated studies/consultancy or received research support from AbbVie, BIOGEN, BMS, ABBVIE, CELGENE, Danone, Eli Lilly, Janssen, MeadJohnson, Medtronic, MSD, MSD France, Nestlé Health Science, Nestlé Nutrition Institute, Pfizer and TAKEDA. All other authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Inc.)

Background and Purpose: In the Netherlands, the 2022 Quality Standard 'Youth in transition from paediatric to adult care' underscores the importance of structured transitional care for young adults with chronic health conditions. Despite this emphasis, detailed knowledge about transition programs and their successful elements remains sparse. This study aims to bridge this gap by exploring nurse-led transition clinics that had successfully implemented core interventions such as a transition coordinator, warm handover, and individual transition plans., Methods: Employing a mixed-methods approach, this study integrated semi-structured interviews with 15 healthcare professionals from both paediatric and adult care across six transition clinics, and surveys from 54 young adults who had transitioned within the last three years. The 'On Your Own Feet Framework' guided the evaluation of transitional care practices. Thematic analysis was applied to qualitative data, while descriptive and inferential statistics were used to analyse quantitative data., Results: The study revealed a strong dedication among healthcare professionals to ensuring smooth transitions and effective collaboration between paediatric and adult care. The young adults reported high satisfaction with their transitions, particularly appreciating the continuity of care and the pivotal role of nurses and nurse practitioners as transition coordinators. However, challenges such as engaging young adults, resource allocation, and financial complexities were noted, alongside areas for improvement including shared decision-making and managing parental involvement. Motivation and collaboration among staff were identified as facilitating factors., Discussion and Conclusion: Our findings emphasize the vital role of nurse-led transition clinics in enhancing healthcare transitions for young adults in the Netherlands, aligning with the principles outlined in the Quality Standard and the On Your Own Feet Framework. While high satisfaction levels with current practices suggest a positive impact, they also highlight that ongoing improvement and adaptation are needed to overcome identified challenges. Successful healthcare transition requires a comprehensive, collaborative approach involving patients, families, and healthcare professionals, supported by organizational and systemic frameworks. This study contributes to a nuanced understanding of transitional care, suggesting a path forward for integrating these practices into standard care models., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: Data on cost-effectiveness of first-line infliximab in paediatric patients with Crohn's disease are limited. Since biologics are increasingly prescribed and accompanied by high costs, this knowledge gap needs to be addressed., Aim: To investigate the cost-effectiveness of first-line infliximab compared to conventional treatment in children with moderate-to-severe Crohn's disease., Methods: We included patients from the Top-down Infliximab Study in Kids with Crohn's disease randomised controlled trial. Children with newly diagnosed moderate-to-severe Crohn's disease were treated with azathioprine maintenance and either five induction infliximab (biosimilar) infusions or conventional induction treatment (exclusive enteral nutrition or corticosteroids). Direct healthcare consumption and costs were obtained per patient until week 104. This included data on outpatient hospital visits, hospital admissions, drug costs, endoscopies and surgeries. The primary health outcome was the odds ratio of being in clinical remission (weighted paediatric Crohn's disease activity index<12.5) during 104 weeks., Results: We included 89 patients (44 in the first-line infliximab group and 45 in the conventional treatment group). Mean direct healthcare costs per patient were €36,784 for first-line infliximab treatment and €36,874 for conventional treatment over 2 years (p = 0.981). The odds ratio of first-line infliximab versus conventional treatment to be in clinical remission over 104 weeks was 1.56 (95%CI 1.03-2.35, p = 0.036)., Conclusions: First-line infliximab treatment resulted in higher odds of being in clinical remission without being more expensive, making it the dominant strategy over conventional treatment in the first 2 years after diagnosis in children with moderate-to-severe Crohn's disease., Trial Registration Number: NCT02517684., (© 2024 The Authors. Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd.)

Background: Maintaining of remission early in the disease course of Crohn's disease (CD) is essential and has major impact on the future prognosis. This study aimed to identify baseline predictors to develop model allowing stratification of patients who will not benefit from long-term azathioprine (AZA) treatment and will require more intensive therapy., Methods: This study was designed to develop clinical prediction rule using retrospective data analysis of pediatric CD patients included in prospective inception cohort. Clinical relapse was defined as necessity of re-induction of remission. Sequence of Cox models was fitted to predict risk of relapse., Results: Out of 1190 CD patients from 13 European centers, 441 were included, 50.3% patients did not experience clinical relapse within 2 years of AZA treatment initiation. Median time to relapse was 2.11 (CI 1.59-2.46) years. Of all the tested parameters available at diagnosis, six were significant in multivariate analyses: C-reactive protein (p = 0.038), body mass index Z-score >0.8 SD (p = 0.002), abnormal sigmoid imaging (p = 0.039), abnormal esophageal endoscopy (p = 0.005), ileocolonic localization (p = 0.023), AZA dose in specific age category (p = 0.031)., Conclusions: Although the possibility of predicting relapse on AZA treatment appears limited, we developed predictive model based on six baseline parameters potentially helpful in clinical decision., Impact: The possibility of predicting relapse on AZA treatment appears to be possible but limited. We identified six independent predictors available at diagnosis of early AZA/6-MP treatment failure in pediatric CD patients. Using combination of these factors, a model applicable to clinical practice was created. A web-based tool, allowing estimation of individual relapse risk in pediatric CD patients on a particular therapeutic regimen, has been developed., (© 2022. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)

Chronic intestinal inflammation underlies inflammatory bowel disease (IBD). Previous studies indicated alterations in the cellular immune system; however, it has been challenging to interrogate the role of all immune cell subsets simultaneously. Therefore, we aimed to identify immune cell types associated with inflammation in IBD using high-dimensional mass cytometry. We analyzed 188 intestinal biopsies and paired blood samples of newly-diagnosed, treatment-naive patients ( n =42) and controls ( n =26) in two independent cohorts. We applied mass cytometry (36-antibody panel) to resolve single cells and analyzed the data with unbiased Hierarchical-SNE. In addition, imaging-mass cytometry (IMC) was performed to reveal the spatial distribution of the immune subsets in the tissue. We identified 44 distinct immune subsets. Correlation network analysis identified a network of inflammation-associated subsets, including HLA-DR + CD38 + EM CD4 + T cells, T regulatory-like cells, PD1 + EM CD8 + T cells, neutrophils, CD27 + TCRγδ cells and NK cells. All disease-associated subsets were validated in a second cohort. This network was abundant in a subset of patients, independent of IBD subtype, severity or intestinal location. Putative disease-associated CD4 + T cells were detectable in blood. Finally, imaging-mass cytometry revealed the spatial colocalization of neutrophils, memory CD4 + T cells and myeloid cells in the inflamed intestine. Our study indicates that a cellular network of both innate and adaptive immune cells colocalizes in inflamed biopsies from a subset of patients. These results contribute to dissecting disease heterogeneity and may guide the development of targeted therapeutics in IBD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 van Unen, Ouboter, Li, Schreurs, Abdelaal, Kooy-Winkelaar, Beyrend, Höllt, Maljaars, Mearin, Mahfouz, Witte, Clemens, Abraham, Escher, Lelieveldt, Pascutti, van der Meulen – de Jong and Koning.)

Introduction: Physical activity is associated with many physiological and psychological health benefits across the lifespan. Children with a chronic disease often have lower levels of daily physical activity, and a decreased exercise capacity compared to healthy peers. In order to learn more about limitations for physical activity, we investigate children with four different chronic diseases: children with a Fontan circulation, children with Broncho Pulmonary Dysplasia (BPD), Pompe disease and inflammatory bowel disease (IBD). Each of these diseases is likely to interfere with physical activity in a different way. Knowing the specific limitations for physical activity would make it possible to target these, and increase physical activity by a personalized intervention. The aim of this study is to first investigate limitations for physical activity in children with various chronic diseases. Secondly, to measure the effects of a tailored exercise intervention, possibly including a personalized dietary advice and/or psychological counseling, on exercise capacity, endurance, quality of life, fatigue, fear for exercise, safety, muscle strength, physical activity levels, energy balance, and body composition. Methods and Analysis: This randomized crossover trial will aim to include 72 children, aged 6-18 years, with one of the following diagnosis: a Fontan circulation, BPD, Pompe disease and IBD. Eligible patients will participate in the 12-week tailored exercise intervention and are either randomized to start with a control period or start with the intervention. The tailored 12-week exercise interventions, possibly including a personalized dietary advice and/or psychological counseling, will be designed based on the found limitations for physical activity in each disease group during baseline measurements by the Rotterdam Exercise Team. Effects of the tailored training interventions will be measured on the following endpoints: exercise capacity (measured by cardiopulmonary exercise test), endurance, physical activity levels, muscle strength, quality of life, fatigue, fear for exercise, disease activity, cardiac function (in children with a Fontan circulation), energy balance, and body composition. Ethics and Dissemination: Conducted according to the Declaration of Helsinki and Good Clinical Practice. Medical-ethical approval was obtained. Trial Registration Number: NL8181, https://www.trialregister.nl/trial/8181., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Scheffers, Helbing, Utens, Dieleman, Dulfer, Noske, van den Broek, Walet, Olieman, Escher, Pijnenburg, van der Ploeg and van den Berg.)

Single genetic mutations predispose to very early onset inflammatory bowel disease (VEO-IBD). Here, we identify a de novo duplication of the 10p15.1 chromosomal region, including the IL2RA locus, in a 2-year-old girl with treatment-resistant pancolitis that was brought into remission by colectomy. Strikingly, after colectomy while the patient was in clinical remission and without medication, the peripheral blood CD4:CD8 ratio was constitutively high and CD25 expression was increased on circulating effector memory, Foxp3 + , and Foxp3 neg CD4 + T cells compared to healthy controls. This high CD25 expression increased IL-2 signaling, potentiating CD4 + T-cell-derived IFNγ secretion after T-cell receptor (TCR) stimulation. Restoring CD25 expression using the JAK1/3-inhibitor tofacitinib controlled TCR-induced IFNγ secretion in vitro. As diseased colonic tissue, but not the unaffected duodenum, contained mainly CD4 + T cells with a prominent IFNγ-signature, we hypothesize that local microbial stimulation may have initiated colonic disease. Overall, we identify that duplication of the IL2RA locus can associate with VEO-IBD and suggest that increased IL-2 signaling predisposes to colonic intestinal inflammation., (© 2021. The Author(s).)

Objective: Developing and evaluating effective transition interventions for young people (16-25 years) with inflammatory bowel disease (IBD) is a high priority. While transition clinics (TCs) have been recommended, little is known about their operating structures and outcomes. This study aimed to gain insight into the value of a TC compared with direct handover care., Design: Controlled mixed-methods evaluation of process outcomes, clinical outcomes and patient-reported outcomes., Setting: Two outpatient IBD clinics in the Netherlands., Participants: Data collection included: semistructured interviews with professionals (n=8), observations during consultations with young people (5×4 hours), medical chart reviews of patients transferred 2 to 4 years prior to data collection (n=56 in TC group; n=54 in control group) and patient questionnaires (n=14 in TC group; n=19 in control group)., Outcomes: Data were collected on service structures and daily routines of the TC, experienced barriers, facilitators and benefits, healthcare use, clinical outcomes, self-management outcomes and experiences and satisfaction of young people with IBD., Results: At the TC, multidisciplinary team meetings and alignment of care between paediatric and adult care providers were standard practice. Non-medical topics received more attention during consultations with young people at the TC. Barriers experienced by professionals were time restrictions, planning difficulties, limited involvement of adult care providers and insufficient financial coverage. Facilitators experienced were high professional motivation and a high case load. Over the year before transfer, young people at the TC had more planned consultations (p=0.015, Cohen's d=0.47). They showed a positive trend in better transfer experiences and more satisfaction. Those in direct handover care more often experienced a relapse before transfer (p=0.003) and had more missed consultations (p=0.034, Cohen's d=-0.43) after transfer., Conclusion: A TC offer opportunities to improve transitional care, but organisational and financial barriers need to be addressed before guidelines and consensus statements in healthcare policy and daily practice can be effectively implemented., Competing Interests: Competing interests: JCE received research support from MSD and has served as advisory board member for Janssen and Abbvie. AvS has served as advisory board member for professional education in diabetes care for Medtronic., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Uncontrolled interferon γ (IFNγ)-mediated T-cell responses to commensal microbiota are a driver of inflammatory bowel disease (IBD). Interleukin-10 (IL-10) is crucial for controlling these T-cell responses, but the precise mechanism of inhibition remains unclear. A better understanding of how IL-10 exerts its suppressive function may allow identification of individuals with suboptimal IL-10 function among the heterogeneous population of IBD patients. Using cells from patients with an IL10RA deficiency or STAT3 mutations, we demonstrate that IL-10 signaling in monocyte-derived dendritic cells (moDCs), but not T cells, is essential for controlling IFNγ-secreting CD4 + T cells. Deficiency in IL-10 signaling dramatically increased IL-1β release by moDCs. IL-1β boosted IFNγ secretion by CD4 + T cells either directly or indirectly by stimulating moDCs to secrete IL-12. As predicted a signature of IL-10 dysfunction was observed in a subgroup of pediatric IBD patients having higher IL-1β expression in activated immune cells and macroscopically affected intestinal tissue. In agreement, reduced IL10RA expression was detected in peripheral blood mononuclear cells and a subgroup of pediatric IBD patients exhibited diminished IL-10 responsiveness. Our data unveil an important mechanism by which IL-10 controls IFNγ-secreting CD4 + T cells in humans and identifies IL-1β as a potential classifier for a subgroup of IBD patients.

Breach of tolerance to gluten leads to the chronic small intestinal enteropathy celiac disease. A key event in celiac disease development is gluten-dependent infiltration of activated cytotoxic intraepithelial lymphocytes (IELs), which cytolyze epithelial cells causing crypt hyperplasia and villous atrophy. The mechanisms leading to gluten-dependent small intestinal IEL infiltration and activation remain elusive. We have demonstrated that under homeostatic conditions in mice, gluten drives the differentiation of anti-inflammatory T cells producing large amounts of the immunosuppressive cytokine interleukin-10 (IL-10). Here we addressed whether this dominant IL-10 axis prevents gluten-dependent infiltration of activated cytotoxic IEL and subsequent small intestinal enteropathy. We demonstrate that IL-10 regulation prevents gluten-induced cytotoxic inflammatory IEL infiltration. In particular, IL-10 suppresses gluten-induced accumulation of a specialized population of cytotoxic CD4 + CD8αα + IEL (CD4 + CTL) expressing Tbx21, Ifng, and Il21, and a disparate non-cytolytic CD4 + CD8α - IEL population expressing Il17a, Il21, and Il10. Concomitantly, IL-10 suppresses gluten-dependent small intestinal epithelial hyperproliferation and upregulation of stress-induced molecules on epithelial cells. Remarkably, frequencies of granzyme B + CD4 + CD8α + IEL are increased in pediatric celiac disease patient biopsies. These findings demonstrate that IL-10 is pivotal to prevent gluten-induced small intestinal inflammation and epithelial damage, and imply that CD4 + CTL are potential new players into these processes.

Disease heterogeneity hampers achieving long-term disease remission in inflammatory bowel disease (IBD). Monitoring ongoing tissue-localized regulatory and inflammatory T-cell responses in peripheral blood would empower disease classification. We determined whether regulatory and inflammatory phenotypes of circulating CD38 + effector (CD62L neg CD4 + ) T cells, a population enriched for cells with mucosal antigen specificity, classify disease course in pediatric IBD patients. In healthy individuals, circulating CD38 + effector T cells had a predominant regulatory component with lower frequencies of IFNγ-secreting T cells, higher frequencies of IL-10-secreting T cells and higher frequencies of inhibitory molecule T-cell immunoglobulin and ITIM domain + (TIGIT) cells than CD38 neg effector T cells. TIGIT expression was stable upon stimulation and marked CD38 + T cells with inhibitory properties. In IBD patients with active intestinal inflammation this predominant regulatory component was lost: circulating CD38 + effector T cells had increased activated CD25 + CD45RA neg and decreased TIGIT + cell frequencies. TIGIT percentages below 25% before treatment associated with shorter duration of clinical remission. In conclusion, phenotypic changes in circulating CD38 + effector T cells, in particular the frequency of TIGIT + cells, classify pediatric IBD patients and predict severity of disease course. These findings have relevance for IBD and can be exploited in graft-versus-host-disease and checkpoint inhibitor-induced inflammation in cancer.

Objective: To evaluate the effectiveness of a disease-specific cognitive behavioral therapy (CBT) protocol on anxiety and depressive symptoms and health-related quality of life (HRQOL) in adolescents and young adults with inflammatory bowel disease (IBD)., Method: A parallel group randomized controlled trial was conducted in 6 centers of (pediatric) gastroenterology. Included were 70 patients and young adults (10-25 years) with IBD and subclinical anxiety and/or depressive symptoms. Patients were randomized into 2 groups, stratified by center: (a) standard medical care (care-as-usual [CAU]) plus disease-specific manualized CBT (Primary and Secondary Control Enhancement Training for Physical Illness; PASCET-PI), with 10 weekly sessions, 3 parent sessions, and 3 booster sessions (n = 37), or (b) CAU only (n = 33). Primary analysis concerned the reliable change in anxiety and depressive symptoms after 3 months (immediate posttreatment assessment). Exploratory analyses concerned (1) the course of anxiety and depressive symptoms and HRQOL in subgroups based on age, and (2) the influence of age, gender, and disease type on the effect of the PASCET-PI., Results: Overall, all participants improved significantly in their anxiety and depressive symptoms and HRQOL, regardless of group, age, gender, and disease type. Primary chi-square tests and exploratory linear mixed models showed no difference in outcomes between the PASCET-PI (n = 35) and the CAU group (n = 33)., Conclusions: In youth with IBD and subclinical anxiety and/or depressive symptoms, preliminary results of immediate post-treatment assessment indicated that a disease-specific CBT added to standard medical care did not perform better than standard medical care in improving psychological symptoms or HRQOL. ClinicalTrials.gov: NCT02265588.

Forskolin-induced swelling (FIS) of intestinal organoids from individuals with cystic fibrosis (CF) measures function of the cystic fibrosis transmembrane conductance regulator (CFTR), the protein mutated in CF.We investigated whether FIS corresponds with clinical outcome parameters and biomarkers of CFTR function in 34 infants diagnosed with CF. Relationships with FIS were studied for indicators of pulmonary and gastrointestinal disease.Children with low FIS had higher levels of immunoreactive trypsinogen (p=0.030) and pancreatitis-associated protein (p=0.039), more often had pancreatic insufficiency (p<0.001), had more abnormalities on chest computed tomography (p=0.049), and had lower z-scores for maximal expiratory flow at functional residual capacity (p=0.033) when compared to children with high FIS values. FIS significantly correlated with sweat chloride concentration (SCC) and intestinal current measurement (ICM) (r= -0.82 and r=0.70, respectively; both p<0.001). Individual assessment of SCC, ICM and FIS suggested that FIS can help to classify individual disease severity.Thus, stratification by FIS identified subgroups that differed in pulmonary and gastrointestinal outcome parameters. FIS of intestinal organoids correlated well with established CFTR-dependent biomarkers such as SCC and ICM, and performed adequately at group and individual level in this proof-of-concept study., Competing Interests: Conflict of interest: J.M. Beekman reports a licensed patent, number CA2859614 A1, for a rapid quantitative assay to measure CFTR function in a primary intestinal culture model. Conflict of interest: J.F. Dekkers reports a licensed patent, number CA2859614 A1, for a rapid quantitative assay to measure CFTR function in a primary intestinal culture model. Conflict of interest: R. Vries reports support from Vertex for drug screening and from CZ for development of diagnostics, outside the submitted work. Conflict of interest: H.A.W.M. Tiddens reports fees/grants from Roche for an industry symposium on treatment in CF, from Novartis for lectures and advisory boards, from CFF for Lung Analysis, from Vertex for Lung Analysis and advisory boards, from Gilead for lectures and advisory boards, and from Chiesi for an investigator-initiated trial, all outside the submitted work. He also reports a licensed combined patent from Vectura on specific targeting with DNase, and an issued patent from the PRAGMA-CF scoring system. He heads the Erasmus Medical Center/Sophia Children's Hospital core laboratory Lung Analysis. Conflict of interest: K.M. de Winter-de Groot has nothing to disclose. Conflict of interest: H.M. Janssens has nothing to disclose. Conflict of interest: R.T. van Uum has nothing to disclose. Conflict of interest: G. Berkers has nothing to disclose. Conflict of interest: A. Vonk has nothing to disclose. Conflict of interest: E. Kruisselbrink has nothing to disclose. Conflict of interest: H. Oppelaar has nothing to disclose. Conflict of interest: H. Clevers has nothing to disclose. Conflict of interest: R.H.J. Houwen has nothing to disclose. Conflict of interest: J.C. Escher has nothing to disclose. Conflict of interest: S.G. Elias has nothing to disclose. Conflict of interest: H.R. de Jonge has nothing to disclose. Conflict of interest: Y.B. de Rijke has nothing to disclose. Conflict of interest: C.K. van der Ent has nothing to disclose., (Copyright ©ERS 2018.)

Background: The co-existence of psychological problems and paediatric inflammatory bowel disease (IBD) is receiving increasing attention. Most studies investigated anxiety and depression, with prevalence rates varying from 0% to 50%. A systematic review is necessary to provide clear insight into the prevalence of anxiety and depression in paediatric IBD., Aim: To systematically evaluate available data on the prevalence of anxiety and depressive symptoms and disorders in paediatric IBD (aged 6-18 years)., Methods: Comprehensive searches were performed in Embase, Medline Ovid, Web of Science, Cochrane, PubMed, PsychInfo Ovid, and Google scholar for studies published from 1994 to 2017. Pooled prevalence rates were calculated using inverse variance heterogeneity models. Meta-regression was used to study if disease type, disease activity and gender influence prevalence., Results: Twenty-eight studies (N = 8107, mean age: 14.3) were identified. Pooled prevalence estimates were 16.4% (95% confidence interval [CI] 6.8%-27.3%) for anxiety symptoms and 4.2% (95% CI 3.6%-4.8%) for anxiety disorders. Pooled prevalence estimates were 15.0% (95% CI 6.4%-24.8%) for depressive symptoms and 3.4% (95% CI 0%-9.3%) for depressive disorders. Meta-regression showed no influence of disease type or gender on these prevalence rates, but studies with a higher percentage of active disease had a higher rate of depressive symptoms., Conclusions: The described pooled prevalence of anxiety and depressive symptoms is lower than in adult IBD. However, due to varying instruments/cut-offs for measuring symptoms and few studies investigating disorders, the results should be interpreted with caution. Cross-cultural use of the same instruments is needed to gain better insight into prevalence rates., (© 2018 John Wiley & Sons Ltd.)

Background: Youths with inflammatory bowel disease (IBD) are at risk for developing anxiety and depressive symptoms with a reported 20%-50% prevalence rate., Aims: This prospective study aimed to: (1) describe the prevalence and severity of anxiety and depressive symptoms in a large Dutch cohort of young IBD patients, and (2) identify demographic and clinical risk factors for anxiety and depression., Methods: IBD patients (n = 374; 10-25 years) were screened for anxiety, depression and quality of life using validated age-specific questionnaires. Patients with elevated scores for anxiety and/or depressive symptoms received a diagnostic interview assessing psychiatric disorders. Demographic and clinical characteristics were retrieved from medical charts. Multiple logistic regression analysis was performed to identify risk factors for anxiety and/or depression., Results: Patients (mean age 18.9 years, 44.1% male, Crohn's disease 60.4%) had disease in remission (75.4%), or mild, moderate and severe clinical disease activity in, respectively, 19.8%, 2.7% and 2.1%. Mild anxiety/depressive symptoms were present in 35.2% and severe symptoms in 12.4% of patients. Elevated symptoms of either anxiety (28.3%), depression (2.9%) or both (15.8%) were found and did not differ between adolescents (10-17 years) and young adults (18-25 years). Active disease significantly predicted depressive symptoms (odds ratio (OR): 4.6 [95% confidence interval [CI]: 2.4-8.8], P < 0.001). Female gender (OR: 1.7 [95% CI: 1.1-2.7]), active disease (OR: 1.9 [95% CI: 1.1-3.2]) and a shorter disease duration (OR: 1.3 [95% CI: 0.6-1.0) (all P < 0.025) significantly predicted anxiety and/or depressive symptoms., Conclusions: Considering the high prevalence of anxiety and depressive symptoms, psychological screening is recommended in young IBD patients. Screening facilitates early recognition and psychological treatment. Female patients and patients with active disease are the most vulnerable., (© 2018 John Wiley & Sons Ltd.)

Objective: Endothelial cells store VWF (von Willebrand factor) in rod-shaped secretory organelles, called Weibel-Palade bodies (WPBs). WPB exocytosis is coordinated by a complex network of Rab GTPases, Rab effectors, and SNARE (soluble NSF attachment protein receptor) proteins. We have previously identified STXBP1 as the link between the Rab27A-Slp4-a complex on WPBs and the SNARE proteins syntaxin-2 and -3. In this study, we investigate the function of syntaxin-3 in VWF secretion., Approach and Results: In human umbilical vein endothelial cells and in blood outgrowth endothelial cells (BOECs) from healthy controls, endogenous syntaxin-3 immunolocalized to WPBs. A detailed analysis of BOECs isolated from a patient with variant microvillus inclusion disease, carrying a homozygous mutation in STX3 (STX3 -/- ), showed a loss of syntaxin-3 protein and absence of WPB-associated syntaxin-3 immunoreactivity. Ultrastructural analysis revealed no detectable differences in morphology or prevalence of immature or mature WPBs in control versus STX3 -/- BOECs. VWF multimer analysis showed normal patterns in plasma of the microvillus inclusion disease patient, and media from STX3 -/- BOECs, together indicating WPB formation and maturation are unaffected by absence of syntaxin-3. However, a defect in basal as well as Ca 2+ - and cAMP-mediated VWF secretion was found in the STX3 -/- BOECs. We also show that syntaxin-3 interacts with the WPB-associated SNARE protein VAMP8 (vesicle-associated membrane protein-8)., Conclusions: Our data reveal syntaxin-3 as a novel WPB-associated SNARE protein that controls WPB exocytosis., (© 2018 American Heart Association, Inc.)

Background: In children with symptoms suggestive of inflammatory bowel disease (IBD) who present in primary care, the optimal test strategy for identifying those who require specialist care is unclear. We evaluated the following three test strategies to determine which was optimal for referring children with suspected IBD to specialist care: 1) alarm symptoms alone, 2) alarm symptoms plus c-reactive protein, and 3) alarm symptoms plus fecal calprotectin., Methods: A prospective cohort study was conducted, including children with chronic gastrointestinal symptoms referred to pediatric gastroenterology. Outcome was defined as IBD confirmed by endoscopy, or IBD ruled out by either endoscopy or unremarkable clinical 12 month follow-up with no indication for endoscopy. Test strategy probabilities were generated by logistic regression analyses and compared by area under the receiver operating characteristic curves (AUC) and decision curves., Results: We included 90 children, of whom 17 (19%) had IBD (n = 65 from primary care physicians, n = 25 from general pediatricians). Adding fecal calprotectin to alarm symptoms increased the AUC significantly from 0.80 (0.67-0.92) to 0.97 (0.93-1.00), but adding c-reactive protein to alarm symptoms did not increase the AUC significantly (p > 0.05). Decision curves confirmed these patterns, showing that alarm symptoms combined with fecal calprotectin produced the diagnostic test strategy with the highest net benefit at reasonable threshold probabilities., Conclusion: In primary care, when children are identified as being at high risk for IBD, adding fecal calprotectin testing to alarm symptoms was the optimal strategy for improving risk stratification.

Background: Faecal calprotectin is considered to be a valid test for ruling out inflammatory bowel disease (IBD) in children with chronic gastrointestinal symptoms in specialist care. In contrast, faecal lactoferrin has higher specificity. The recent availability of both as point-of-care tests (POCTs) makes them attractive for use in primary care., Objective: To evaluate the test characteristics of calprotectin and lactoferrin POCTs for diagnosing IBD in symptomatic children., Methods: We defined two prospective cohorts of children with chronic gastrointestinal symptoms: (i) children presenting to primary care (primary care cohort); (ii) children referred for specialist care (referred cohort). Baseline POCT results were compared with the outcome of either endoscopic assessment or 12 months follow-up. Clinicians were blinded to the POCT results., Results: In the primary care cohort, none of the 114 children had IBD, and the calprotectin and lactoferrin POCTs had specificities of 0.95 (0.89-0.98) and 0.98 (0.93-0.99), respectively. In the referred cohort, 17 of the 90 children had IBD: the sensitivity of POCT calprotectin and POCT lactoferrin were both 0.94 (0.72-0.99); and the specificity was 0.93 (0.84-0.97) and 0.99 (0.92-1.00), respectively. The POCT calprotectin could reduce the referral rate by 76% and POCT lactoferrin by 81%, while missing one child with IBD (6%)., Conclusion: A diagnostic test strategy in primary care using a simple POCT calprotectin or lactoferrin has the potential to reduce the need for referral for further diagnostic work-up in specialist care, with a low risk of missing a child with IBD., (© The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Familial hemophagocytic lymphohistiocytosis 5 (FHL5) is an autosomal recessive disease caused by mutations in STXBP2, coding for Munc18-2, which is required for SNARE-mediated membrane fusion. FHL5 causes hematologic and gastrointestinal symptoms characterized by chronic enteropathy that is reminiscent of microvillus inclusion disease (MVID). However, the molecular pathophysiology of FHL5-associated diarrhea is poorly understood. Five FHL5 patients, including four previously unreported patients, were studied. Morphology of duodenal sections was analyzed by electron and fluorescence microscopy. Small intestinal enterocytes and organoid-derived monolayers displayed the subcellular characteristics of MVID. For the analyses of Munc18-2-dependent SNARE-protein interactions, a Munc18-2 CaCo2-KO model cell line was generated by applying CRISPR/Cas9 technology. Munc18-2 is required for Slp4a/Stx3 interaction in fusion of cargo vesicles with the apical plasma membrane. Cargo trafficking was investigated in patient biopsies, patient-derived organoids, and the genome-edited model cell line. Loss of Munc18-2 selectively disrupts trafficking of certain apical brush-border proteins (NHE3 and GLUT5), while transport of DPPIV remained unaffected. Here, we describe the molecular mechanism how the loss of function of Munc18-2 leads to cargo-selective mislocalization of brush-border components and a subapical accumulation of cargo vesicles, as it is known from the loss of polarity phenotype in MVID.

Introduction: Crohn's disease (CD) is a chronic inflammatory disease predominantly affecting the gastrointestinal tract. CD usually requires lifelong medication and is accompanied by severe complications, such as fistulae and strictures, resulting in surgery. Infliximab (IFX) is very effective for treating paediatric patients with CD, but is currently only registered for therapy refractory patients-the so-called step-up strategy. We hypothesise that using IFX first-line, that is, top-down, will give more mucosal healing, fewer relapses, less complications, need for surgery and hospitalisation., Methods and Analysis: This international multicentre open-label randomised controlled trial includes children, aged 3-17 years, with new-onset, untreated CD with moderate-to-severe disease activity (weighted Paediatric Crohn's Disease Activity Index (wPCDAI)>40). Eligible patients will be randomised to top-down or step-up treatment. Top-down treatment consists of 5 IFX infusions combined with azathioprine (AZA). After these 5 infusions, patients will continue AZA. Patients randomised to step-up will receive standard induction treatment, either oral prednisolone or exclusive enteral nutrition, combined with AZA as maintenance treatment. The primary outcome is clinical remission (wPCDAI<12.5) at 52 weeks without need for additional CD-related therapy or surgery. Total follow-up is 5 years. Secondary outcomes include clinical disease activity, mucosal healing by endoscopy (at week 10 and optionally week 52), faecal calprotectin, growth, quality of life, medication use and adverse events., Ethics and Dissemination: Conducted according to the Declaration of Helsinki and Good Clinical Practice. Medical-ethical approval will be obtained for each site., Trial Registration Number: NCT02517684; Pre-results., Competing Interests: JCE is part of the Scientific Advisory Committee of Janssen and Abbvie and received a research grant from Merck Sharp & Dohme (MSD). LdR reports a presentation on an Abbvie sponsored meeting.

Purpose: In specialist care, fecal calprotectin (FCal) is a commonly used noninvasive diagnostic test for ruling out inflammatory bowel disease (IBD) in children with chronic gastrointestinal symptoms. The aim of this study was to evaluate the diagnostic accuracy of FCal for IBD in symptomatic children in primary care., Methods: We studied 2 prospective cohorts of children with chronic diarrhea, recurrent abdominal pain, or both: children initially seen in primary care (primary care cohort) and children referred to specialist care (referred cohort). FCal (index test) was measured at baseline and compared with 1 of the 2 reference standards for IBD: endoscopic assessment or 1-year follow-up. Physicians were blinded to FCal results, and values greater than 50 μg/g feces were considered positive. We determined specificity in the primary care cohort and sensitivity in the referred cohort., Results: None of the 114 children in the primary care cohort ultimately received a diagnosis of IBD. The specificity of FCal in the primary care cohort was 0.87 (95% CI, 0.80-0.92). Among the 90 children in the referred cohort, 17 (19%) ultimately received a diagnosis of IBD. The sensitivity of FCal in the referred cohort was 0.99 (95% CI, 0.81-1.00)., Conclusions: The findings of this study suggest that a positive FCal result in children with chronic gastrointestinal symptoms seen in primary care is not likely to be indicative of IBD. A negative FCal result is likely to be a true negative, which safely rules out IBD in children in whom a primary care physician considers referral to specialist care., (© 2016 Annals of Family Medicine, Inc.)

Introduction: Adolescents with inflammatory bowel disease (IBD) show a higher prevalence of depression and anxiety, compared to youth with other chronic diseases. The inflammation-depression hypothesis might explain this association, and implies that treating depression can decrease intestinal inflammation and improve disease course. The present multicentre randomised controlled trial aims to test the effectiveness of an IBD-specific cognitive-behavioural therapy (CBT) protocol in reducing symptoms of subclinical depression and anxiety, while improving quality of life and disease course in adolescents with IBD., Methods and Analysis: Adolescents with IBD (10-20 years) from 7 hospitals undergo screening (online questionnaires) for symptoms of depression and anxiety. Those with elevated scores of depression (Child Depression Inventory (CDI) ≥13 or Beck Depression Inventory (BDI) II ≥14) and/or anxiety (Screen for Child Anxiety Related Disorders: boys ≥26, girls ≥30) receive a psychiatric interview. Patients meeting criteria for depressive/anxiety disorders are referred for psychotherapy outside the trial. Patients with elevated (subclinical) symptoms are randomly assigned to medical care-as-usual (CAU; n=50) or CAU plus IBD-specific CBT (n=50)., Main Outcomes: (1) reduction in depressive and/or anxiety symptoms after 3 months and (2) sustained remission for 12 months., Secondary Outcomes: quality of life, psychosocial functioning, treatment adherence. In addition, we will assess inflammatory cytokines in peripheral blood mononuclear cells and whole blood RNA expression profiles. For analysis, multilevel linear models and generalised estimating equations will be used., Ethics and Dissemination: The Medical Ethics Committee of the Erasmus MC approved this study. If we prove that this CBT improves emotional well-being as well as disease course, implementation is recommended., Trial Registration Number: NCT02265588.

Background & Aims: Increased levels of anti-tissue transglutaminase (tTG) have been associated with reduced weight and bone mineral density (BMD) in symptomatic patients with celiac disease. Little is known about the effects of these antibodies in patients with subclinical or other forms of celiac disease. We examined associations between anti-tTG positivity and growth and BMD., Methods: In a population-based prospective cohort study, serum samples were collected from children (median age, 6 years; n = 4442) and analyzed for anti-tTG. All children were born between April 2002 and January 2006 and were not previously diagnosed with celiac disease. Children were categorized as anti-tTG negative (<7 U/mL, n = 4249) or anti-tTG positive (≥7 U/mL, n = 57). Children's levels of anti-tTG were further categorized on the basis of ≥10 times upper limit of normal (70 U/mL). Height, weight, and body mass index (BMI) age- and sex-adjusted standard deviation scores (SDS) ([observed value - mean]/SD) were obtained by using Dutch reference growth charts. BMD was measured by dual-energy x-ray absorptiometry. Multivariable linear regression and linear mixed models were performed., Results: Children who tested positive for anti-tTG had reduced growth in weight SDS/year (reduction of 0.05; 95% CI, reductions of 0.09-0.01) and BMI SDS/year (reduction of 0.10; 95% CI, reductions of 0.18-0.01) from 6 months until 6 years, compared with children without anti-tTG; they also tended to have reduced growth in height from 6 months until 6 years (reduction of 0.02 SDS/year; 95% CI, reductions of 0.06-0.02). Children who tested positive for anti-tTG were shorter (0.29 SDS shorter; 95% CI, reductions of 0.55-0.04 SDS), weighed less (0.38 SDS less; 95% CI, reductions of 0.64-0.12), and had lower BMIs (0.26 SDS less; 95% CI, reductions of 0.49-0.03) and BMDs (0.26 SDS less; 95% CI, reductions of 0.45-0.08) at 6 years of age than anti-tTG negative children., Conclusions: Anti-tTG positive children without gastrointestinal symptoms have lower BMDs and reduced growth trajectories until they are 6 years old. This suggests that subclinical or potential celiac disease can affect BMD and growth., (Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Microvillus inclusion disease (MVID) is a disorder of intestinal epithelial differentiation characterized by life-threatening intractable diarrhea. MVID can be diagnosed based on loss of microvilli, microvillus inclusions, and accumulation of subapical vesicles. Most patients with MVID have mutations in myosin Vb that cause defects in recycling of apical vesicles. Whole-exome sequencing of DNA from patients with variant MVID showed homozygous truncating mutations in syntaxin 3 (STX3). STX3 is an apical receptor involved in membrane fusion of apical vesicles in enterocytes. Patient-derived organoid cultures and overexpression of truncated STX3 in Caco-2 cells recapitulated most characteristics of variant MVID. We conclude that loss of STX3 function causes variant MVID., (Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Intact interleukin-10 receptor (IL-10R) signaling on effector and T regulatory (Treg) cells are each independently required to maintain immune tolerance. Here we show that IL-10 sensing by innate immune cells, independent of its effects on T cells, was critical for regulating mucosal homeostasis. Following wild-type (WT) CD4(+) T cell transfer, Rag2(-/-)Il10rb(-/-) mice developed severe colitis in association with profound defects in generation and function of Treg cells. Moreover, loss of IL-10R signaling impaired the generation and function of anti-inflammatory intestinal and bone-marrow-derived macrophages and their ability to secrete IL-10. Importantly, transfer of WT but not Il10rb(-/-) anti-inflammatory macrophages ameliorated colitis induction by WT CD4(+) T cells in Rag2(-/-)Il10rb(-/-) mice. Similar alterations in the generation and function of anti-inflammatory macrophages were observed in IL-10R-deficient patients with very early onset inflammatory bowel disease. Collectively, our studies define innate immune IL-10R signaling as a key factor regulating mucosal immune homeostasis in mice and humans., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: Low disease prevalence and lack of uniform reference standards in primary care induce methodological challenges for investigating the diagnostic accuracy of a test. We present a study design that copes with these methodological challenges and discuss the methodological implications of our choices, using a quality assessment tool for diagnostic accuracy studies (QUADAS-2)., Design: The study investigates the diagnostic value of fecal calprotectin for detecting inflammatory bowel disease in children presenting with chronic gastrointestinal symptoms in primary care. It is a prospective cohort study including two cohorts of children: one cohort will be recruited in primary care and the other in secondary/tertiary care. Test results of fecal calprotectin will be compared to one of the two reference standards for inflammatory bowel disease: endoscopy with histopathological examination of mucosal biopsies or assessment of clinical symptoms at 1-year follow-up., Discussion: According to QUADAS-2 the use of two reference standards and the recruitment of patients in two populations may cause differential verification bias and spectrum bias, respectively. The clinical relevance of this potential bias and methods to adjust for this are presented. This study illustrates the importance of awareness of the different kinds of bias that result from choices in the design phase of a diagnostic study in a low prevalence setting. This approach is exemplary for other diagnostic research in primary care.

Objective: In current clinical practice, optimal treatment of inflammatory bowel disease (IBD) aims at the induction and maintenance of clinical remission. Clinical remission is apparent when laboratory markers of inflammation are normal and clinical symptoms are absent. However, sub-clinical inflammation can still be present. A detailed analysis of the immune status during this inactive state of disease may provide a useful tool to categorize patients with clinical remission into subsets with variable states of immune activation., Design: By using Affymetrix GeneChips, we analysed RNA gene expression profiles of peripheral blood leukocytes from pediatric IBD patients in clinical remission and controls. We performed (un)supervised clustering analysis of IBD-associated genes and applied Ingenuity® pathway software to identify specific molecular profiles between patients., Results: Pediatric IBD patients with disease in clinical remission display heterogeneously distributed gene expression profiles that are significantly distinct from controls. We identified three clusters of IBD patients, each displaying specific expression profiles of IBD-associated genes., Conclusion: The expression of immune- and IBD-associated genes in peripheral blood leukocytes from pediatric IBD patients in clinical remission was different from healthy controls, indicating that sub-clinical immune mechanisms are still active during remission. As such, RNA profiling of peripheral blood may allow for non-invasive patient subclassification and new perspectives in treatment regimes of IBD patients in the future.

Celiac disease (CD) is caused by inflammatory CD4(+) T-cell responses to dietary gluten. It is unclear whether interleukin (IL)-21 and IL-17A contribute to CD onset and lesion severity; therefore, we investigated IL-21 and IL-17A expression in biopsies from pediatric CD patients with different histopathological scores. High numbers of IL-21-producing cells were observed in pediatric CD lesions, even Marsh 1-2 lesions, whereas increased numbers of IL-17 secreting cells were not observed. Intraepithelial lymphocytes, CD4(+) T cells and also neutrophils secreted IL-21. Flow cytometry of lamina propria cells revealed a large population of IL-21- and interferon-γ (IFN-γ)-secreting CD3(+) T cells that did not secrete IL-17A. Adult CD patient biopsies also contained high numbers of IL-21-positive cells; however, enhanced numbers of IL-17-positive cells were observed in a small subgroup of patients with severe lesions. As duodenal tissue damage increases contact with microbe-associated molecular patterns, we hypothesized that microbial sensing by Toll-like receptors (TLRs) modulates T cell-derived cytokine secretion. Costimulation with TLR3 ligands during polyclonal T-cell activation significantly increased IL-21 secretion, whereas TLR2 ligands selectively enhanced IL-17A. These results demonstrate that an IL-17A-independent increase in IL-21 production by CD4(+) T cells is characteristic of pediatric CD. We hypothesize that incidental IL-17 secretion is caused by tissue damage rather than gluten-specific responses.

The influence of childhood nutrition on the development of constipation beyond the period of weaning and breastfeeding is relatively understudied. In addition, eating patterns in childhood can be highly correlated with overweight and sedentary behaviour, which may also have an influence on constipation. The aim of this study was to assess whether common dietary patterns, sedentary behaviour and childhood overweight are associated with constipation in childhood. The study was embedded in a population-based prospective birth cohort. Information on dietary intake was obtained by a food frequency questionnaire at the child's age of 14 months (n = 2420). The adherence scores on a 'Health conscious' and 'Western-like' diet were extracted from principal component analysis. At the age of 24, 36 and 48 months, information on constipation and sedentary behaviour, and weight and height was obtained by parental-derived questionnaires and from the child health centres, respectively. Adherence to a 'Western-like' dietary pattern was associated with a higher prevalence of constipation up to 48 months [adjusted odds ratio (aOR); 95% confidence interval (CI): 1.39; 1.02-1.87], which was not mediated by overweight or sedentary behaviour. Adherence to a 'Health Conscious' dietary pattern was only associated at short term, with a lower prevalence of constipation at 24 months (aOR; 95%CI: 0.65; 0.44-0.96). No association was found between overweight, sedentary behaviour and constipation. Our results suggest that specific dietary patterns in early childhood could be associated with higher or lower risks for constipation, but these effects are time-dependent. Overweight and sedentary behaviour seem to not have a major role on constipation in childhood., (© 2012 John Wiley & Sons Ltd.)

Background: Celiac disease (CD) is an intestinal inflammation driven by gluten-reactive CD4(+) T cells. Due to lack of selective markers it has not been determined whether defects in inducible regulatory T cell (Treg) differentiation are associated with CD. This is of importance as changes in numbers of induced Treg could be indicative of defects in mucosal tolerance development in CD. Recently, we have shown that, after encounter of retinoic acid during differentiation, circulating gut-imprinted T cells express CD62L(neg)CD38(+). Using this new phenotype, we now determined whether alterations occur in the frequency of natural CD62L(+)Foxp3(+) Treg or mucosally-imprinted CD62L(neg)CD38(+)Foxp3(+) Treg in peripheral blood of CD patients. In particular, we compared pediatric CD, aiming to select for disease at onset, with adult CD., Methods: Cell surface markers, intracellular Foxp3 and Helios were determined by flow cytometry. Foxp3 expression was also detected by immunohistochemistry in duodenal tissue of CD patients., Results: In children, the percentages of peripheral blood CD4(+)Foxp3(+) Treg were comparable between CD patients and healthy age-matched controls. Differentiation between natural and mucosally-imprinted Treg on the basis of CD62L and CD38 did not uncover differences in Foxp3. In adult patients on gluten-free diet and in refractory CD increased percentages of circulating natural CD62L(+)Foxp3(+) Treg, but normal mucosally-imprinted CD62L(neg)CD38(+)Foxp3(+) Treg frequencies were observed., Conclusions: Our data exclude that significant numeric deficiency of mucosally-imprinted or natural Foxp3(+) Treg explains exuberant effector responses in CD. Changes in natural Foxp3(+) Treg occur in a subset of adult patients on a gluten-free diet and in refractory CD patients.

Short-term bowel adaptation has been documented, but data on long-term effects are scarce. The aim of the present study was to evaluate the long-term consequences of infantile short bowel syndrome (SBS). A cross-sectional assessment (2005-7) of growth, nutritional status, defecation pattern and health status in individuals with a history of infantile SBS, born between 1975 and 2002, were performed. Data were compared with reference values of healthy controls and presented as means and standard deviations or median and ranges. A total of forty subjects (sixteen male and twenty-four female; mean age 14·8 (SD 6·8) years) had received parenteral nutrition during a median of 110 (range 43-2345) d, following small bowel resection. The mean standard deviation scores (SDS) for weight for height and target height (TH) of the children were normal; mean SDS for height for age was - 0·9 (SD 1·3). The median BMI adults was 19·9 (range 17-26) kg/m2; mean SDS for height for age was - 1·0 (range - 2·5 to 1·5). Height in general was significantly shorter than TH, and 53 % of children and 78 % of adults were below TH range. Most subjects had normal body fat percentage (%BF). SDS for total body bone mineral density were generally normal. The SDS for bone mineral content (BMC) of the children were - 1·0 (SD 1·1). Mean energy intake was 91 % of the estimated average requirements. The frequencies of defecation and bowel complaints of the subjects were significantly higher than in healthy controls. In conclusion, infantile SBS results in shorter stature than was expected from their calculated TH. BMC was lower than reference values, but the subjects had normal weight for height and %BF.

Background & Aims: We evaluated the efficacy and safety of infliximab for inducing and maintaining benefit in children with moderately to severely active ulcerative colitis (UC)., Methods: Patients (6-17 years old) who had active UC (Mayo scores of 6-12; endoscopic subscores ≥ 2) and had not responded to or tolerated conventional treatment were given 5 mg/kg infliximab at weeks 0, 2, and 6. The primary end point was response at week 8 (decreases in Mayo scores ≥ 30% and ≥ 3 points and decreases in rectal bleeding subscores of ≥ 1 or an absolute subscore of ≤ 1). At week 8, only responders were randomly assigned to groups given infliximab every 8 or 12 weeks (q8w or q12w) and followed through week 54. Maintenance end points included pediatric UC activity index scores <10 points, defined as remission., Results: At week 8, infliximab induced a response in 73.3% of patients (44 of 60) (95% confidence interval, 62.1%-84.5%; a positive result was defined by 95% confidence interval lower limit >40%). Among responders, twice as many were in remission at week 54 after q8w (8 of 21, 38.1%) than q12w (4 of 22, 18.2%; P = .146) therapy. Assuming the q8w remission rate for responders, the overall remission rate at week 54 would be 28.6%. Serious adverse events and infusion reactions occurred in similar proportions in the q8w and q12w groups. No deaths, malignancies, opportunistic infections, tuberculosis, or delayed hypersensitivity reactions were reported., Conclusions: Infliximab was safe and effective, inducing a response at week 8 in 73.3% of pediatric patients with moderate to severely active UC who did not respond to conventional therapy. The overall remission rate at week 54 for all enrolled patients was 28.6%, assuming the more effective q8w remission rate., (Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background: Infliximab is effective for induction and maintenance of remission in children with moderately to severely active Crohn's disease (CD)., Aim: To evaluate the long-term efficacy of infliximab treatment in paediatric CD., Methods: In this observational, multicentre study, all paediatric CD patients in The Netherlands treated with infliximab from October 1992 to November 2009 and with minimal follow-up of 3 months since start of infliximab, were studied., Results: One hundred and fifty-two CD patients [81M; median age at start of infliximab 15.0 years (IQR 13.1-16.4)] received a median number of 10.5 infliximab infusions (IQR 6-21). Median follow-up after start of infliximab was 25 months (IQR 13-40). Kaplan-Meier analysis showed that the cumulative probability of losing response to infliximab in patients who initially required repeated infusions was 13%, 40% and 50% after 1, 3 and 5 years, respectively. Seventy-four patients (49%) needed dose adjustments, with a median time to any adjustment of 6 months., Conclusions: Duration of effect of infliximab is limited as 50% of patients on infliximab maintenance treatment lose their therapeutic response after 5 years. Dose adjustments after start of infliximab are frequently needed to regain therapeutic benefit. These findings emphasise the need for effective, long-term treatment strategies for paediatric CD., (© 2010 Blackwell Publishing Ltd.)

The etiology of growth impairment in Crohn's disease (CD) has been inadequately explained by nutritional, hormonal, and/or disease-related factors, suggesting that genetics may be an additional contributor. The aim of this cross-sectional study was to investigate genetic variants associated with linear growth in pediatric-onset CD. We genotyped 951 subjects (317 CD patient-parent trios) for 64 polymorphisms within 14 CD-susceptibility and 23 stature-associated loci. Patient height-for-age Z-score < -1.64 was used to dichotomize probands into growth-impaired and nongrowth-impaired groups. The transmission disequilibrium test (TDT) was used to study association to growth impairment. There was a significant association between growth impairment in CD (height-for-age Z-score < -1.64) and a stature-related polymorphism in the dymeclin gene DYM (rs8099594) (OR = 3.2, CI [1.57-6.51], p = 0.0007). In addition, there was nominal over-transmission of two CD-susceptibility alleles, 10q21.1 intergenic region (rs10761659) and ATG16L1 (rs10210302), in growth-impaired CD children (OR = 2.36, CI [1.26-4.41] p = 0.0056 and OR = 2.45, CI [1.22-4.95] p = 0.0094, respectively). Our data indicate that genetic influences due to stature-associated and possibly CD risk alleles may predispose CD patients to alterations in linear growth. This is the first report of a link between a stature-associated locus and growth impairment in CD., (© 2010 The Authors Annals of Human Genetics © 2010 Blackwell Publishing Ltd/University College London.)

Many diseases with unknown etiology may be caused by unidentified viruses. Sequence-independent amplification revealed a new astrovirus, similar to VA1, in a 4-year-old male diagnosed with celiac disease. This expands the geographic range of this virus to include Europe and may associate astrovirus infection with the onset of celiac disease.

Background & Aims: Lubiprostone alleviates constipation by stimulating intestinal fluid secretion, purportedly through activation of ClC-2-type Cl(-) channels. Intestinal obstruction is also a recurrent cause of distress in cystic fibrosis (CF) patients, caused by loss of CF transmembrane conductance regulator (CFTR) Cl(-) channel activity. Because ClC-2 recruitment might be beneficial to CF patients, we investigated lubiprostone's mode of action., Methods: Cl(-) transport was measured in an Ussing chamber, in 3 model systems: (1) T84 colonocytes, (2) intestinal epithelium of wild-type and CF mice, and (3) intestinal epithelium of CF patients and controls., Results: In T84 monolayers, lubiprostone induced a robust secretory response. Selective permeabilization of the basolateral plasma membrane revealed that lubiprostone activated an apical Cl(-) conductance. The lubiprostone response was attenuated by H89, an inhibitor of the cAMP-dependent protein kinase, and lubiprostone precluded responsiveness to the cAMP agonist forskolin. CFTR blockage by CFTRinh172, but not ClC-2 blockage by CdCl(2), inhibited the lubiprostone response. Lubiprostone induced a CdCl(2)-insensitive secretory response in mouse intestine, but failed to induce intestinal Cl(-) secretion in Cftr-null mice. Correspondingly, lubiprostone induced a secretory response in human intestinal epithelium, but not in tissue of CF patients. The EP(4)-type prostanoid receptor antagonist L-161,982 blocked the lubiprostone response in all 3 models studied. In T84 cells, lubiprostone induced a rise in cAMP levels that was sensitive to EP(4)-receptor blockage., Conclusions: Lubiprostone enhances intestinal Cl(-) and fluid secretion via prostanoid receptor signaling, triggering activation of CFTR. Therefore, it is of limited use for treatment of CF-related intestinal disease.

The accumulation of certain species of bacteria in the intestine is involved in both tissue homeostasis and immune-mediated pathologies. The host mechanisms involved in controlling intestinal colonization with commensal bacteria are poorly understood. We observed that under specific pathogen-free or germ-free conditions, intragastric administration of Pseudomonas aeruginosa, E. coli, Staphylococcus aureus, or Lactobacillus gasseri resulted in increased colonization of the small intestine and bacterial translocation in mice lacking Cd1d, an MHC class I-like molecule, compared with WT mice. In contrast, activation of Cd1d-restricted T cells (NKT cells) with alpha-galactosylceramide caused diminished intestinal colonization with the same bacterial strains. We also found prominent differences in the composition of intestinal microbiota, including increased adherent bacteria, in Cd1d-/- mice in comparison to WT mice under specific pathogen-free conditions. Germ-free Cd1d-/- mice exhibited a defect in Paneth cell granule ultrastructure and ability to degranulate after bacterial colonization. In vitro, NKT cells were shown to induce the release of lysozyme from intestinal crypts. Together, these data support a role for Cd1d in regulating intestinal colonization through mechanisms that include the control of Paneth cell function.

Background: Azathioprine is widely used in the treatment of children with inflammatory bowel disease. The occurrence and type of adverse events to azathioprine may be related to thiopurine S-methyltransferase (TPMT) enzyme activity and to inosine triphophate pyrophosphatase (ITPase) deficiency., Aim: Investigate frequencies of functional TPMT polymorphisms and ITPA polymorphisms and their association with the occurrence of adverse events during azathioprine therapy in a paediatric inflammatory bowel disease population., Methods: Seventy-two azathioprine treated paediatric inflammatory bowel disease patients, 47% girls, mean age 12.5 years (range 6.5-17.5), were assessed for TPMT and ITPA polymorphisms and for adverse events. The relation between polymorphisms and adverse events is evaluated., Results: Of all azathioprine treated patients, 11 experienced an adverse event for which azathioprine was stopped: pancreatitis (n = 4), leucopenia (n = 2) and 'general malaise' (n = 5). Of the 11 patients who stopped azathioprine because of adverse events, 10 had wild-type alleles for all investigated genotypes. Genotyping of ITPA 94C>A polymorphisms showed that two patients were homozygous, both tolerated azathioprine well., Conclusions: No association of functional ITPA and TPMT polymorphisms and the occurrence of azathioprine related adverse events could be detected. Pharmacogenetic assessment prior to thiopurine therapy does not seem warranted.

This third section of the European Crohn's and Colitis Organisation (ECCO) Consensus on the management of Crohn's disease concerns postoperative recurrence, fistulating disease, paediatrics, pregnancy, psychosomatics, extraintestinal manifestations, and alternative therapy. The first section on definitions and diagnosis reports on the aims and methods of the consensus, as well as sections on diagnosis, pathology, and classification of Crohn's disease. The second section on current management addresses treatment of active disease, maintenance of medically induced remission, and surgery of Crohn's disease.

Background: Systemic glucocorticosteroid therapy is effective in Crohn's disease, but is associated with side-effects. Budesonide has high topical anti-inflammatory activity, but considerably lower systemic activity than other oral glucocorticosteroids., Aim: To evaluate the systemic exposure to budesonide (controlled ileal release capsules) in children and adults with active Crohn's disease, and to assess the suppression of plasma cortisol., Methods: In an open label study, patients (eight children and six adults) with active Crohn's disease received 9 mg budesonide (Entocort capsules) orally once daily for 7 days. Plasma concentrations were determined on the seventh day of administration, and pharmacokinetic parameters were calculated. For reference, 0.5 mg budesonide was given intravenously separately. Plasma cortisol levels were compared with the pre-treatment baseline values., Results: Systemic exposure to budesonide (AUC0-24 h) after 1 week of oral administration was 41 +/- 21 nmol/L x h (mean +/- s.d.) in children and 35 +/- 20 nmol/L x h in adults. The estimated systemic availability in children was 9 +/- 5% and in adults 11 +/- 7%. The mean plasma cortisol (AUC0-24 h) decreased by 64 +/- 18% in children and by 50 +/- 27% in adults., Conclusions: The systemic exposure, systemic availability and cortisol suppression after oral administration of 9 mg budesonide were similar in children and adults with active Crohn's disease. Budesonide was well tolerated and no clinically important safety-related findings were identified.