Review on Advances in Pediatric Endoscopy in the Management of Inflammatory Bowel Disease

Over the past decades, an increased importance has been given to gastrointestinal (GI) endoscopy in the management of children with inflammatory bowel diseases (IBD), considering that mucosal healing has been recognized as the optimal endpoint in the treat-to-target paradigm. The recent advances in technology and anesthesia have facilitated the comprehensive evaluation of the GI tract. In this review, we will discuss the role of ileocolonoscopy, upper GI endoscopy, and device-assisted enteroscopy in the work-up and management of pediatric Crohn’s disease (CD) and ulcerative colitis, with particular attention on non-invasive endoscopic techniques, such as wireless capsule endoscopy. We will also analyze the most commonly used endoscopic scoring systems, including small bowel scoring systems and endoscopic recurrence grading of neo-terminal ileum CD. Moreover, we will focus on the endoscopic management of complications, such as strictures, that commonly require surgery. Lastly, we will discuss cancer surveillance in children with IBD, with particular consideration of the role of high-definition endoscopic equipment and chromoendoscopy in dysplasia detection rates.

Management of collagenous gastritis in children: Case series and literature review

Collagenous gastritis (CG) is a rare histopathological finding on gastric biopsies in children. It is associated with abdominal pain and iron deficiency anemia, usually not respondent to oral iron supplements. The aim of this study was to describe our experience in the management of pediatric patients with CG. Moreover, we propose to review the literature on this topic. We retrospectively reviewed all pediatric patients diagnosed with CG at our centre from January 2014 to January 2019. Three pediatric patients (2 F, mean age 12.3) were diagnosed with CG during the study period. Two presented with moderate and one with severe anemia. Symptoms were abdominal pain, asthenia and headache in two and asthenia and abdominal pain in one. All underwent upper and lower gastrointestinal endoscopy. All were firstly started with oral iron supplements with no benefit, principally due to poor compliance secondary to the worsening of the epigastric pain and proton pump inhibitor resistance. Therefore, they underwent ferric carboxymaltose (FCM) infusion with good clinical and laboratory response. Patients received a mean of two infusions/year, with stable hemoglobin levels and no adverse outcomes. Our review failed to identify a consistent response to specific treatments. Considering the apparent benign nature of the disease, symptomatic and supportive treatments are advisable. Iron deficiency anemia is largely present and therapy with oral iron supplements is not always successful. In our study, FCM infusion was effective in increasing the key blood indices in patients who poorly tolerated oral supplements.

PARP1 Activation Induces HMGB1 Secretion Promoting Intestinal Inflammation in Mice and Human Intestinal Organoids

Extracellular High-mobility group box 1 (HMGB1) contributes to the pathogenesis of inflammatory disorders, including inflammatory bowel diseases (IBD). Poly (ADP-ribose) polymerase 1 (PARP1) has been recently reported to promote HMGB1 acetylation and its secretion outside cells. In this study, the relationship between HMGB1 and PARP1 in controlling intestinal inflammation was explored. C57BL6/J wild type (WT) and PARP1^-/- mice were treated with DSS to induce acute colitis, or with the DSS and PARP1 inhibitor, PJ34. Human intestinal organoids, which are originated from ulcerative colitis (UC) patients, were exposed to pro-inflammatory cytokines (INFγ + TNFα) to induce intestinal inflammation, or coexposed to cytokines and PJ34. Results show that PARP1^-/- mice develop less severe colitis than WT mice, evidenced by a significant decrease in fecal and serum HMGB1, and, similarly, treating WT mice with PJ34 reduces the secreted HMGB1. The exposure of intestinal organoids to pro-inflammatory cytokines results in PARP1 activation and HMGB1 secretion; nevertheless, the co-exposure to PJ34, significantly reduces the release of HMGB1, improving inflammation and oxidative stress. Finally, HMGB1 release during inflammation is associated with its PARP1-induced PARylation in RAW264.7 cells. These findings offer novel evidence that PARP1 favors HMGB1 secretion in intestinal inflammation and suggest that impairing PARP1 might be a novel approach to manage IBD.

Proteomic Analysis Identifies Three Reliable Biomarkers of Intestinal Inflammation in the Stools of Patients With Inflammatory Bowel Disease

BACKGROUND

Faecal biomarkers have emerged as important tools in managing of inflammatory bowel disease [IBD], which includes Crohn's disease [CD] and ulcerative colitis [UC].

AIM

To identify new biomarkers of gut inflammation in the stools of IBD patients using a proteomic approach.

METHODS

Proteomic analysis of stools was performed in patients with both active CD and CD in remission and in controls by 2-DIGE and MALDI-TOF/TOF MS. An ELISA was used to confirm results in a second cohort of IBD patients and controls.

RESULTS

2-DIGE analysis detected 70 spots in the stools of patients with active CD or patients in remission CD and in controls. MALDI-TOF/TOF MS analysis identified 21 proteins with Chymotrypsin C, Gelsolin and Rho GDP-dissociation inhibitor 2 [RhoGDI2] best correlating with the levels of intestinal inflammation. Results were confirmed in a second cohort of IBD patients and controls [57 CD, 60 UC, 31 controls]. The identified faecal markers significantly correlated with the severity of intestinal inflammation in IBD patients [SES-CD in CD, Mayo endoscopic subscore in UC] [CD; Chymotrypsin-C: r = 0.64, p < 0.001; Gelsolin: r = 0.82, p < 0.001; RhoGDI2: r = 0.64, p < 0.001; UC; Chymotrypsin-C: r = 0.76, p < 0.001; Gelsolin: r = 0.75, p < 0.001; RhoGDI2: r = 0.63, p < 0.001]. Moreover, ROC analysis showed that Gelsolin [p < 0.0002] and RhoGDI2 [p < 0.0001] in CD, and RhoGDI2 [p = 0.0004] in UC, have higher sensitivity and specificity than faecal calprotectin in discriminating between patients and controls.

CONCLUSIONS

We show for the first time that 2-DIGE is a reliable method to detect proteins in human stools. Three novel faecal biomarkers of gut inflammation have been identified that display good specificity and sensitivity for identifying IBD and significantly correlate with IBD severity.

ZNF281 Promotes Colon Fibroblast Activation in TGFβ1-Induced Gut Fibrosis

Crohn’s disease (CD) and ulcerative colitis (UC) are chronic inflammatory disorders of the gastrointestinal tract. Chronic inflammation is the main factor leading to intestinal fibrosis, resulting in recurrent stenosis, especially in CD patients. Currently, the underlying molecular mechanisms of fibrosis are still unclear. ZNF281 is a zinc-finger transcriptional regulator that has been characterized as an epithelial-to-mesenchymal transition (EMT)-inducing transcription factor, suggesting its involvement in the regulation of pluripotency, stemness, and cancer. The aim of this study is to investigate in vivo and in vitro the role of ZNF281 in intestinal fibrogenesis. Intestinal fibrosis was studied in vivo in C57BL/6J mice with chronic colitis induced by two or three cycles of administration of dextran sulfate sodium (DSS). The contribution of ZNF281 to gut fibrosis was studied in vitro in the human colon fibroblast cell line CCD-18Co, activated by the pro-fibrotic cytokine TGFβ1. ZNF281 was downregulated by siRNA transfection, and RNA-sequencing was performed to identify genes regulated by TGFβ1 in activated colon fibroblasts via ZNF281. Results showed a marked increase of ZNF281 in in vivo murine fibrotic colon as well as in in vitro human colon fibroblasts activated by TGFβ1. Moreover, abrogation of ZNF281 in TGFβ1-treated fibroblasts affected the expression of genes belonging to specific pathways linked to fibroblast activation and differentiation into myofibroblasts. We demonstrated that ZNF281 is a key regulator of colon fibroblast activation and myofibroblast differentiation upon fibrotic stimuli by transcriptionally controlling extracellular matrix (ECM) composition, remodeling, and cell contraction, highlighting a new role in the onset and progression of gut fibrosis.

Colonic inflammation accelerates the progression of liver disease: A protective role of dipotassium glycyrrhizate

BACKGROUND

The incidence of non-alcoholic fatty liver disease (NAFLD) and its more severe and progressive form, non-alcoholic steatohepatitis (NASH) is increasing worldwide. Gut inflammation seems to concur to the pathogenesis of NASH. No drugs are currently approved for NASH treatment.

AIMS

To investigate if inflamed gut directly contributes to the progression of NASH through gut epithelial and vascular barrier impairment and to evaluate the efficacy of dipotassium glycyrrhizate (DPG) to improve the liver disease.

METHODS

A NASH model was set up by feeding mice, for 8 and 13 weeks, with high fat diet with high fructose and glucose (HFD-FG) supplemented periodically with dextran sulfate sodium (DSS) in drinking water. A group was also treated with DPG by gavage. Histological, immunohistochemical and molecular analysis were performed.

RESULTS

DSS-induced colitis increased steatosis, inflammatory (IL-6, TNFα, NLRP3, MCP-1) as well as fibrotic (TGF-β, α-SMA) mediator expression in HFD-FG mice. Beneficial effect of DPG was associated with restoration of intestinal epithelial and vascular barriers, evaluated respectively by ZO-1 and PV-1 expression, that are known to limit bacterial translocation.

CONCLUSION

Colonic inflammation strongly contributes to the progression of NASH, likely by favouring bacterial translocation. DPG treatment could represent a novel strategy to reduce liver injury.

Evaluation of Risk for Thromboembolic Events in Pediatric Inflammatory Bowel Disease

OBJECTIVES

The occurrence of thrombotic events in adult patients with inflammatory bowel disease (IBD) is linked to multiple interactions between hereditary and acquired risk factors. There are few published data concerning children with iBD. The aim of this study was to investigate the presence of thromboembolic risk factors also in children with iBD.

METHODS

We enrolled three groups of children: one with Crohn disease (cD), one with ulcerative colitis (Uc), and a control group of healthy subjects. For all the participants the potential thromboembolic risk was evaluated clinically and with laboratory tests.

RESULTS

We studied: 30 children (25.6%) with CD, 28 (23.9%) with UC, and 59 (50.4%) healthy control subjects. Regarding Pediatric Crohn Disease Activity Index, no significant differences between thromboembolic risk factors and disease activity were detected. Instead, in the patients with UC, stratified with the Pediatric Ulcerative Colitis Activity Index, there was a statistically significant difference in serum fibrinogen levels between patients with mild and moderate/severe disease [3.8 (3.2-4.5) g/L vs 5.7 (4.8-6.2) g/L, P  < 0.0032]. serum homocysteine levels were lower in healthy controls than in CD (P = 0.176) and UC (P = 0.026). An increased level ofhomocysteine in UC with a homozygous mutation in the methylene tetrahydrofolate reductase C677T gene was also observed.

CONCLUSIONS

Our study showed that children with IBD have clinical features, acquired and congenital factors that can increase thrombotic risk, similarly to adults.

A new double immunohistochemistry method to detect mucosal anti-transglutaminase IgA deposits in coeliac children

BACKGROUND

Intestinal transglutaminase (TG2) IgA deposits represent early marker of coeliac disease (CeD) and can predict the evolution towards intestinal atrophy.

AIMS

To validate a double immunohistochemistry method for the determination of intestinal TG2 IgA deposits on formalin-fixed paraffin-embedded biopsies.

METHODS

Immunohistochemistry was tested on: 1) children with overt CeD [persistently positive serum IgA anti-tissue transglutaminase type 2 (TGA-IgA) with moderate or low titer, and histological findings of CeD]; 2) potential CeD (persistently positive serum TGA-IgA and normal intestinal mucosa) and 3) controls (negative serum TGA-IgA and normal intestinal mucosa).

RESULTS

Samples from 61 children were analyzed (32 overt CeD, 14 potential CeD, and 15 controls). Deposits appeared as focal, multifocal, or confluent extracellular foci of red and brown staining colocalization in the sub-epithelium and around mucosal vessels. Deposits were present in all 32 children with overt CeD and in 9/14 potential CeD. Deposits were never observed in the 15 controls. Patients with higher serum level of TGA-IgA and with mucosal atrophy showed mostly a multifocal/diffuse pattern of deposits distribution. The bulb appeared most severely involved. In potential CeD deposits showed mainly a focal distribution.

CONCLUSION

Our results indicate double immunohistochemistry as promising diagnostic tool to improve diagnosis of CeD.

Fecal and mucosal microbiota profiling in pediatric inflammatory bowel diseases

BACKGROUND

An altered gut microbiota profile has been widely documented in inflammatory bowel diseases (IBD). The intestinal microbial community has been more frequently investigated in the stools than at the level of the mucosa, while most of the studies have been performed in adults. We aimed to define the gut microbiota profile either by assessing fecal and colonic mucosa samples (inflamed or not) from pediatric IBD patients.

PATIENTS AND METHODS

Fecal and colonic samples from pediatric IBD (Crohn's disease or ulcerative colitis) and controls were analyzed. The relative abundance of bacteria at phylum and genus/species levels and bacterial diversity were determined through 16S rRNA sequence-based of fecal and mucosal microbiota analysis.

RESULTS

A total of 59 children with IBD (26 Crohn's disease, 33 ulcerative colitis) and 39 controls were analyzed. A clear separation between IBD and controls in the overall composition of fecal and mucosal microbiota was found, as well as a reduced bacterial richness in the fecal microbiota of IBD. At the phylum level, abundance of Proteobacteria and Actinobacteria occurred in fecal microbiota of IBD, while species with anti-inflammatory properties (i.e., Ruminococcus) were reduced. Fusobacterium prevailed in inflamed IBD areas in comparison to noninflamed and controls samples.

CONCLUSION

Significant alterations in gut microbiota profile were shown in our IBD pediatric patients, in whom an abundance of species with a proinflammatory mucosal activity was clearly detected. An analysis of gut microbiota could be incorporated in designing personalized IBD treatment scenarios in future.

Assessment of a new score for capsule endoscopy in pediatric Crohn's disease (CE-CD)

Background and study aims  Two scores have been implemented to standardize capsule endoscopic (CE) findings in patients with Crohn's disease (CD): Lewis score (LS) and Capsule Endoscopy Crohn's Disease Activity Index (CECDAI). Both have limitations and are not well validated in the pediatric population. The aim of our study was to assess a new score (capsule endoscopy - Crohn's disease index, CE-CD) in pediatric patients with CD and to compare it to preexisting scores. Patients and methods  This was a double-center, retrospective study involving pediatric subjects with CD who underwent CE. Correlation analyses between CE-CD, endoscopy scores and noninvasive markers of disease activities were performed. The ability of different CE scores to predict clinical and endoscopic outcomes was evaluated with regression and survival analyses. Results  A total of 312 subjects were analyzed. The CE-CD score showed a moderate (Pearson's r = 0.581, P  < 0.001) and strong (r = 0.909, P  < 0.001) association with LS and CECDAI, respectively. CE-CD was a statistically significant predictor of hospitalization (hazard ratio [HR]1.061), treatment escalation (HR 1.062), steroid therapy (HR 1.082), clinical (HR 1.064) and endoscopic (HR 1.060) relapse over the twenty-four months ( P  < 0.001). Subjects with mucosal inflammation according to CE-CD (CE-CD ≥ 9) had worse outcomes compared to patients without inflammation (CE-CD < 9) (Log rang test < 0.001). Conclusions  The CE-CD score is a simple, reliable, reproducible, and predictive score for evaluation of small bowel inflammation in pediatric patients with CD. Prospective validation is needed to confirm the applicability of this new index in clinical practice.

Emerging Roles of Gut Virome in Pediatric Diseases

In the last decade, the widespread application of shotgun metagenomics provided extensive characterization of the bacterial "dark matter" of the gut microbiome, propelling the development of dedicated, standardized bioinformatic pipelines and the systematic collection of metagenomic data into comprehensive databases. The advent of next-generation sequencing also unravels a previously underestimated viral population (virome) present in the human gut. Despite extensive efforts to characterize the human gut virome, to date, little is known about the childhood gut virome. However, alterations of the gut virome in children have been linked to pathological conditions such as inflammatory bowel disease, type 1 diabetes, malnutrition, diarrhea and celiac disease.

Disease Activity Patterns in the First 5 Years After Diagnosis in Children With Ulcerative Colitis: A Population-Based Study

BACKGROUND

The aim of this study was to define clusters of activity in a population-based cohort during the first 5 years after diagnosis in children with ulcerative colitis [UC] and to identify early prognostic risk factors.

METHODS

All UC patients from the SIGENP IBD registry with a complete follow-up of at least 5 years were included. Active disease was defined every 6 months in the presence of at least one of the following: clinical activity [Paediatric Ulcerative Colitis Activity Index ≥ 35]; endoscopic activity [Mayo score ≥ 1]; faecal calprotectin > 250 µg/g; hospitalization; surgery; or treatment escalation. Formula-based clusters were generated based on four published questionnaire-based activity patterns in adults, plus one additional cluster.

RESULTS

In total, 226 patients were identified. Forty-two [19%] had moderate-severe chronically active disease, 31 [14%] chronic-intermittent, 75 [33%] quiescent, 54 [24%] active disease in the first 2 years after the diagnosis, then sustained remission, and 24 [11%] a remission in the first 2 years then an active disease. Mild disease onset along with a lower clinical severity not requiring the use of corticosteroids at 6 months were related to a quiescent disease course at the next follow-up (logistic model area under the curve 0.86 [95% confidence interval 0.78-0.94]; positive predictive value 67%; negative predictive value 70%). Eight per cent of patients needed surgery, none in the quiescent group [p = 0.04].

CONCLUSIONS

More than one-third of children with UC present with a chronically active or intermittent course during the first 5 years of follow-up. A significant group of patients has active disease in the first 2 years and then sustained remission. Interestingly, after initial treatment, one-third of patients have well-controlled disease throughout.

Transition of inflammatory bowel disease patients from pediatric to adult care: an observational study on a joint-visits approach

Background

Transition from pediatric to adult care of patients affected by Inflammatory Bowel Disease (IBD) is a critical step that needs specific care and multidisciplinary involvement. The aim of our study was to evaluate the outcome of the transition process of a cohort of IBD patients, exploring their readiness and the possible impact on quality of life.

Methods

This observational study followed transitioned IBD patients from pediatric to adult care. Transition was carried-out through combined visits, jointly performed by the pediatrician and the adult gastroenterologist. Clinical data were collected before and after transition. A subgroup of patients was submitted to an anonymous online questionnaire of 38 items based on the validated questionnaires TRAQ and SIBDQ within the first 6 months from the beginning of the transition process.

Results

Eighty-two patients with IBD were enrolled, with a mean age at transition of 20.2±2.7 years. Before transition, 40.2% of patients already had major surgery and 64.6% started biologics. At transition, 24% of patients were in moderate to severe active phase of their disease and 40% of them had already been treated with ≥ 2 biologics. The mean score of the TRAQ questionnaires collected is 3.4±1.5 and the mean score of SIBDQ is 53.9±9.8. A significant association was found between a TRAQ mean score > 3 and a SIBDQ > 50 (p=0.0129). Overall, 75% of patients had a positive opinion of the transition model adopted.

Conclusions

A strong association has been found between TRAQ and SIBDQ questionnaires, showing how transition readiness has a direct impact on the quality of life of the young adult with IBD.

Dietary Compliance and Quality of Life in Celiac Disease: A Long-Term Follow-Up of Primary School Screening-Detected Patients

Background: Whether the diagnostic approach for celiac disease (CD) can really affect quality of life (QoL) and dietary compliance remains controversial. Aims: This study aimed to evaluate QoL and compliance to gluten-free diet (GFD) in adolescents/young adults diagnosed with CD through a screening strategy during childhood compared to age-matched CD patients diagnosed by case-finding and to assess whether follow-up at a referral center for CD influences compliance and QoL. Materials and Methods: Thirty-seven CD patients who were diagnosed by screening programs (SC-group) and 38 age-matched CD patients diagnosed due to symptoms (CF-group) were enrolled. Patients were asked to answer a questionnaire on QoL, dietary compliance, and follow-up care for CD. Results: Twenty-nine patients of the SC-group (median age 18.0 years, interquartile range [IQR] 16.0-19.0) and 31 patients of the CF-group (median age 17.0 years, IQR 15.5-18.0) completed the questionnaire. No significant difference relating adherence to the GFD and QoL was shown between the two groups. The majority (93.5%) of CF-group regularly had annual follow-up at a referral center compared to 37.9% of the SC-group (p < 0.001). Conclusion: The diagnostic strategy does not seem to impact QoL and dietary compliance. However, implementation of follow-up might still be necessary for patients identified through screening.

Fecal High-Mobility Group Box 1 as a Marker of Early Stage of Necrotizing Enterocolitis in Preterm Neonates

Introduction: An early diagnosis of necrotizing enterocolitis (NEC), a major gastrointestinal emergency in preterm newborns, is crucial to improve diagnostic approach and prognosis. We evaluated whether fecal high-mobility group box protein 1 (HMGB1) may early identify preterms at risk of developing NEC. Materials and Methods: A case-control study including neonates admitted at the Neonatal Intensive Care Unit (NICU) of the Sapienza University Hospital "Umberto I" in Rome, from July 2015 to December 2016. Stool samples obtained from cases (preterm newborns with NEC) and controls (newborns without NEC) were collected at the enrolment (T0) and within 7-14 days after the first sample collection (T1). HMGB1, extracted and measured with western blot, was reported as densitometry units (DUS). Results: HMGB1 levels in 30 cases (n = 28-Bell stage 1, n = 2 Bell stage 2) were higher [T0: 21,462 DUS (95% CI, 16,370-26,553 DUS)-T1: 17,533 DUS (95% CI, 13,052-22,014 DUS)] than in 30 preterm controls [T0: 9,446 DUS (95% CI, 6,147-12,746 DUS)-T1: 9,261 DUS (95% CI, 5,126-13,396 DUS), p < 0.001). Preterm newborns showed significant higher levels of HMGB1 (15,690 DUS (95% CI, 11,929-19,451 DUS)] in comparison with 30 full-term neonates with birth weight >2,500 g [6,599 DUS (95% CI, 3,141-10,058 DUS), p = 0.003]. Multivariate analysis showed that the risk of NEC was significantly (p = 0.012) related to the HMGB1 fecal levels at T0. Conclusions: We suggest fecal HMGB1 as a reliable marker of early NEC in preterm neonates. This study supports further investigation on the role of fecal HMGB1 assessment in managing preterm newborns at risk of NEC. Further studies are advocated to evaluate diagnostic accuracy of this marker in more severe forms of the disease.

Effect of Limosilactobacillus reuteri LRE02-Lacticaseibacillus rhamnosus LR04 Combination on Antibiotic-Associated Diarrhea in a Pediatric Population: A National Survey

Probiotics are living microorganisms, which, upon oral ingestion, may prevent antibiotic-associated diarrhea (AAD) through the normalization of an unbalanced gastrointestinal flora. The objective of this study was to evaluate the benefits of a probiotic combination (Limosilactibacillus reuteri LRE02-DSM 23878 and Lacticaseibacillus rhamnosus LR04-DSM 16605) on the prevention of AAD in an outpatient pediatric setting. Questionnaires were delivered to pediatricians by each patient/parent during the visits after antibiotics and probiotics treatment to monitor physiological parameters. The primary outcome of both groups (probiotics and no probiotics treated) was the evaluation of the prevalence of AAD between the two groups. Evaluation of stool consistency using the Bristol Stool Scale (BSS) score was performed, as well as the evaluation of AAD duration, frequencies of daily evacuation, and the beginning of diarrhea and weight loss during AAD in both groups and related to antibiotic categories. Results indicated that probiotics, at the recommended dosage of 1.2 × 10⁹ CFU (Colony Forming Unit) per day for 30 days, are associated with lower rates of AAD and a decreased number of days with diarrhea, independent of the type of antibiotic used. Moreover, the use of probiotics resulted in a normal stool consistency in a shorter time period, as evaluated by the BSS.

Multi-omics analysis reveals the influence of genetic and environmental risk factors on developing gut microbiota in infants at risk of celiac disease

BACKGROUND

Celiac disease (CD) is an autoimmune digestive disorder that occurs in genetically susceptible individuals in response to ingesting gluten, a protein found in wheat, rye, and barley. Research shows that genetic predisposition and exposure to gluten are necessary but not sufficient to trigger the development of CD. This suggests that exposure to other environmental stimuli early in life, e.g., cesarean section delivery and exposure to antibiotics or formula feeding, may also play a key role in CD pathogenesis through yet unknown mechanisms. Here, we use multi-omics analysis to investigate how genetic and early environmental risk factors alter the development of the gut microbiota in infants at risk of CD.

RESULTS

Toward this end, we selected 31 infants from a large-scale prospective birth cohort study of infants with a first-degree relative with CD. We then performed rigorous multivariate association, cross-sectional, and longitudinal analyses using metagenomic and metabolomic data collected at birth, 3 months and 6 months of age to explore the impact of genetic predisposition and environmental risk factors on the gut microbiota composition, function, and metabolome prior to the introduction of trigger (gluten). These analyses revealed several microbial species, functional pathways, and metabolites that are associated with each genetic and environmental risk factor or that are differentially abundant between environmentally exposed and non-exposed infants or between time points. Among our significant findings, we found that cesarean section delivery is associated with a decreased abundance of Bacteroides vulgatus and Bacteroides dorei and of folate biosynthesis pathway and with an increased abundance of hydroxyphenylacetic acid, alterations that are implicated in immune system dysfunction and inflammatory conditions. Additionally, longitudinal analysis revealed that, in infants not exposed to any environmental risk factor, the abundances of Bacteroides uniformis and of metabolite 3-3-hydroxyphenylproprionic acid increase over time, while those for lipoic acid and methane metabolism pathways decrease, patterns that are linked to beneficial immunomodulatory and anti-inflammatory effects.

CONCLUSIONS

Overall, our study provides unprecedented insights into major taxonomic and functional shifts in the developing gut microbiota of infants at risk of CD linking genetic and environmental risk factors to detrimental immunomodulatory and inflammatory effects. Video Abstract.

Gluten-free diet impact on dynamics of pancreatic islet-specific autoimmunity detected at celiac disease diagnosis

OBJECTIVE

Almost 6% of celiac disease (CD) patients at diagnosis are positive for at least one of the main pancreatic islet autoantibodies that characterize type 1 diabetes (T1D). Few information, dated back to almost two decades ago, exist as to whether a gluten-free diet (GFD) could reduce the islet-specific autoimmunity detected in patients at CD diagnosis. Aim of the study was to evaluate the impact of GFD on 31 patients who presented islet-specific autoimmunity at CD diagnosis.

METHODS

CD patient sera collected at diagnosis and throughout the GFD were analyzed for the main humoral autoantibodies so far identified in T1D, directed against one or more among insulin, glutamic-acid decarboxylase, tyrosine-phosphatase 2, and zinc cation-efflux transporter autoantigens.

RESULTS

GFD (median duration 39 months) was associated to a decrease or disappearance of the islet-specific autoantibodies in 71% of CD patients. Almost 80% of the patients who became autoantibody-negative during the GFD were positive for only one of the islet-specific autoimmune markers at CD diagnosis, with none of them developing diabetes. Conversely, 80% of the CD patients positive at diagnosis for ≥2 islet-specific autoantibodies were still positive after more than two years of GFD, with 25% of them developing T1D.

CONCLUSIONS

Various factors appear to influence, individually or in combination, the effects of the GFD on pancreatic islet-specific autoimmune response detected at CD diagnosis. These factors include the number of diabetes autoantibodies found at CD diagnosis, the adherence to the GFD, its duration and an asymptomatic clinical presentation of CD.

Mucosal healing in Crohn's disease: new insights

INTRODUCTION

Traditional management of patients with Crohn's disease includes symptoms and quality of life improvement. With the advent of biological agents, mucosal healing has become an achievable goal, documented through endoscopy. However, due to the transmural nature of inflammation, the prevention of bowel damage should be included in the aims of a targeted therapeutic strategy.

AREAS COVERED

Updated literature has been searched in PubMed from 2008 to 2020. This review focuses on the state of the art in the innovative therapeutic goals in Crohn's disease, also considering still controversial aspects and future research topics in the management of Crohn's disease.

EXPERT OPINION

Although a widely agreed view supports the notion that mucosal healing and bowel damage control may promote beneficial outcomes (i.e. reduction in hospitalization and surgical rates, avoidance of steroids), long-term robust data are still missing. On the other hand, the development of -omics techniques has expanded our knowledge of the pathogenetic mechanism underlying inflammatory bowel disease and opened up new horizons in precision or personalized medicine.

Neuropsychiatric manifestations in celiac disease

Celiac disease (CD) is a systemic, chronic immune-mediated disorder elicited by gluten and related prolamines in genetically susceptible subjects. Main manifestations of CD involve the digestive tract; however, a growing body of evidence supports the theory that symptoms may occur in every part of the body. It is known that some patients with CD can be asymptomatic, and additionally, the incidence of "nonclassical" CD with extraintestinal presentation is apparently increasing. We aimed to perform a thorough review of existing evidence for neurological manifestations of CD, providing an up-to-date description of prevalence and examining the pathogenetic mechanisms possibly involved. Neurological presentations are rare in children but as many as 36% of adult patients present with neurological findings. With severe malnutrition after progression of CD, different vitamin deficiencies may develop. Such problems can in turn overlap with previous neurological abnormalities including ataxia, epilepsy, neuropathy, dementia, and cognitive disorders. Here, the most prevalent clinical manifestations in adults and children have been discussed in further detail. Further research is needed to achieve a complete understanding of the nervous system involvement in CD, but clinicians should always remember that neurological and psychiatric symptoms might be part of the CD spectrum of manifestations.

Functional analysis of gut microbiota and immunoinflammation in children with autism spectrum disorders

BACKGROUND AND AIMS

Recent evidence implicates gut microbiota (GM) and immune alterations in autism spectrum disorders (ASD). We assess GM profile and peripheral levels of immunological, neuronal and bacterial molecules in ASD children and controls. Alarmin HMGB1 was explored as a non-invasive biomarker to monitor gastrointestinal (GI) symptoms.

METHODS

Thirty ASD children and 14 controls entered into the study. GM metagenomic analysis was performed for 16 ASD patients and 7 controls. GM functional profile was assessed by GO term analysis. Blood levels of IL-1β, TNFα, TGFβ, IL-10, INFγ, IL-8, lipopolysaccharide, Neurotensin, Sortilin1 and GSSG/GSH ratio were analyzed in all subjects by ELISA. Fecal HMGB1 was analyzed by Western blot.

RESULTS

We observed a significant decrease in bacterial diversity. Furthermore, 82 GO terms underrepresented in ASD. Four of them pointed at 3,3 phenylpropionate catabolism and were imputable to Escherichia coli (E. coli) group. Serum levels of TNFα, TGFβ, NT, and SORT-1 increased in ASD patients. Fecal levels of HMGB1 correlated with GI sign severity in ASD children.

CONCLUSIONS

We suggest that a decrease of E. coli might affect the propionate catabolism in ASD. We report occurrence of peripheral inflammation in ASD children. We propose fecal HMGB1 as a non-invasive biomarker to detect GI symptoms.

Infections and malignancies risks related to TNF-α-blocking agents in pediatric inflammatory bowel diseases

Introduction: Tumor necrosis factor-α (TNF-α)-blocking agents are drugs approved for the treatment of inflammatory bowel diseases (IBDs). Infliximab and adalimumab are approved for the treatment of IBD in the pediatric setting with the improvement of therapeutic management. Biological agents, also in the pediatric population, can be administered either alone or in combination with immunomodulators. Their use has raised safety concerns regarding the risk of infections and malignancies.Areas covered: A broad review of the safety concerns for the use of anti-TNF-α drugs in children with IBD was performed, and information regarding the risk of infections and malignancies were updated, also in comparison with the safety of traditional drugs such as steroids and/or immunosuppressants.Expert commentary: Anti-TNF-α drugs have shown favorable safety profiles, and adalimumab treatment is associated with lower immunogenicity compared with infliximab. Heightened awareness and vigilant surveillance leading to prompt diagnosis and treatment are important for optimal management.

A Treat to Target Strategy Using Panenteric Capsule Endoscopy in Pediatric Patients With Crohn's Disease

BACKGROUND & AIMS

Pan-enteric capsule endoscopy (PCE) is effective for assessment of small intestinal and colonic Crohn's disease (CD) in pediatric patients. We aimed to determine whether PCE can be used to monitor mucosal healing and deep remission, in a treat to target strategy for pediatric patients with CD.

METHODS

We performed a prospective study of 48 children with a diagnosis of CD at a tertiary care pediatric gastroenterology unit; 46 patients were included in the final analysis. Biomarker, imaging, and PCE analyses were performed at baseline and after 24 and 52 weeks. Small bowel and colonic mucosal healing were defined by Lewis scores <135 and simple endoscopic score for CD ≤1, respectively. Clinical remission was defined as defined as a pediatric CD activity index score <10 and biomarker-based remission based on normal levels of biomarkers; deep remission was defined as a combination of clinical remission, biomarker-based remission, and mucosal healing. Treatments were adjusted based on findings from PCE (imaging was considered only for patients with negative findings from PCE). Therapies were introduced, optimized, switched, or combined at the discretion of treating clinicians. The primary outcome was the ability of PCE to assess mucosal healing and deep remission at 3 timepoints and to guide a treat to target strategy.

RESULTS

PCE detected inflammation in 34 patients (71%) at baseline, 22 patients (46%) at week 24, and 18 patients (39%) at week 52 (P for comparison among timepoints <.05). Findings from PCE led to a change in therapy for 34 patients (71%) at baseline and 11 patients (23%) at 24 weeks, whereas only 2 patients with negative results from PCE (4%) changed therapies based on findings from imaging. When the treat to target strategy was applied, proportions of patients with mucosal healing and deep remission increased from 21% at baseline, to 54% at week 24, to 58% at week 52 (P for comparison among timepoints <.05); 2 patients (4%) did not respond to treatment.

CONCLUSION

In a prospective study of 48 children with CD, we found a treat to target strategy, based on findings from PCE, to significantly increase the proportions of patients with mucosal healing and deep remission.

CLINICAL TRIAL

gov no: NCT03161886.

Hypoallergenicity of a thickened hydrolyzed formula in children with cow's milk allergy

BACKGROUND

Allergy to cow's milk is the most frequent allergy occurring in infants and young children. The dietary management of these patients consists of the elimination of any cow's milk proteins from the diet, and for formula-fed infants, the substitution of the usual infant formula with an adapted formula that is generally based on extensively hydrolyzed cow's milk proteins. The American Academy of Pediatrics has established specific criteria to confirm the hypoallergenicity of a formula intended for these children.

AIM

To assess the hypoallergenicity of a new thickened extensively hydrolyzed casein-based formula (TeHCF) in children with cow's milk allergy (CMA).

METHODS

Children diagnosed with CMA through a double-blind placebo-controlled food challenge (DBPCFC) were randomly administered increased doses of a placebo formula or the TeHCF [Allernova, new thickener including fibres (Novalac)] under double-blind conditions and medical surveillance on two separate days. Otherwise, both of these formulas and a cow's milk-based formula were randomly introduced to children who were highly suspected of having CMA on three separate days. Immediate and late reactions occurring after the introduction of any of these formulas were thoroughly recorded by the physician at the hospital and reported by parents to the physician after hospital discharge, respectively. If the children tolerated the TeHCF during the DBPCFC, they were exclusively fed this formula during a 3-mo period where potential allergic symptoms, anthropometric parameters, as secondary outcomes, and adverse events were registered. The Cow's Milk-related Symptoms Score (CoMiSSTM) was assessed and anthropometric parameters were compared to World Health Organization (WHO) reference data.

RESULTS

Of the 30 children included in the study, the CMA diagnosis of 29 (mean age: 8.03 ± 7.43 mo) patients was confirmed by a DBPCFC. The children all tolerated the TeHCF during both the challenge and the subsequent 3-mo feeding period, which they all completed. During the latter period, the CoMiSSTM remained at a very low level, never exceeding its baseline value (1.4 ± 2.0), growth parameters were within WHO reference standards and no adverse event related to the TeHCF was reported. Over the first week of this period, the proportion of patients with digestive discomfort significantly decreased from 20.7% (6/29) to 3.4% (1/29), P = 0.025. The proportion of satisfaction with the overall effect of the formula reported by the parents and investigator was high, as was the formula acceptability by the child.

CONCLUSION

The new TeHCF meets the hypoallergenicity criteria according to the American Academy of Pediatrics standards, confirming that the tested TeHCF is adapted to the dietary management of children with CMA. Moreover, growth was adequate in the included population.

Use of biosimilars in inflammatory bowel disease: a position update of the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD)

The first infliximab biosimilar for the treatment of inflammatory bowel disease (IBD) was introduced in 2013, and today eight anti-TNF alpha biosimilars (three for infliximab and five for adalimumab) have been approved and licensed by the European Medicines Agency. Biosimilars present great potential in terms of cost saving and possible consequential reinvestment in the health care system. The increasing knowledge about the process of biosimilar development and use in IBD and the publication of many prospective clinical studies and real-life clinical experiences have progressively changed the point of view of IBD physicians. In the present position paper, the Italian Group for the Study of Inflammatory Bowel Disease present and discuss their updated statements and positions on this topic, with emphasis on the concepts of biosimilarity and extrapolation across indications, safety and immunogenicity, interchangeability and switching, automatic substitution, and, finally, patient education about biosimilars.

Dipotassium Glycyrrhizate Improves Intestinal Mucosal Healing by Modulating Extracellular Matrix Remodeling Genes and Restoring Epithelial Barrier Functions

Gut mucosal healing (MH) is considered a key therapeutic target and prognostic parameter in the management of inflammatory bowel disease (IBD). The dipotassium glycyrrhizate (DPG), a salt of the glycoconjugated triterpene glycyrrhizin, has been shown to inhibit the High Mobility Group Box 1 (HMGB1) protein, an allarmin strongly implicated in the pathogenesis of most inflammatory and auto-immune disorders. Here we discuss new insights on how DPG acts on MH comparing the acute phase and the recovery phase from experimental colitis in mice. We found that DPG strongly accelerates MH by differently regulating pro-inflammatory (CXCL1, CXCL3, CXCL5, PTGS2, IL-1β, IL-6, CCL12, CCL7) and wound healing (COL3A1, MMP9, VTN, PLAUR, SERPINE, CSF3, FGF2, FGF7, PLAT, TIMP1) genes as observed only during the recovery phase of colitis. Relevant issue is the identification of extracellular matrix (ECM) remodeling genes, VTN, and PLAUR, as crucial genes to achieve MH during DPG treatment. Furthermore, a noticeable recovery of intestinal epithelial barrier structural organization, wound repair ability, and functionality is observed in two human colorectal adenocarcinoma cell lines exposed to DPG during inflammation. Thus, our study identifies DPG as a potent tool for controlling intestinal inflammation and improving MH.

Quantitative Assessment of Shotgun Metagenomics and 16S rDNA Amplicon Sequencing in the Study of Human Gut Microbiome

The analysis of microbiota composition in humans, animals, and built environments is important because of emerging roles and applications in a broad range of disease and ecological phenotypes. Next Generation Sequencing is the current method of choice to characterize microbial community composition. The taxonomic profile of a microbial community can be obtained either by shotgun analysis of random DNA fragments or through 16S ribosomal RNA gene (rDNA) amplicon sequencing. It has been previously shown that the 16S rDNA amplicon sequencing approach yields quantitatively and qualitatively different results compared to shotgun metagenomics when the two techniques are used to assess microbial community composition on the same samples. However, most of such comparisons were either based on the recovery of 16S rDNA sequences in the shotgun metagenomics data or limited to a single microbiome or synthetic samples. Direct comparison of shotgun metagenomics and 16S rDNA amplicon sequencing on the same samples was performed only once in the recent literature, suggesting that the two methods yield comparable results. Here, we set out to compare the outcome of these two alternative approaches to the microbiome characterization in human gut microbiomes from stool samples. To this end, we processed six different samples with both techniques. We report here that shotgun next generation sequencing metagenomics allows much deeper characterization of the microbiome complexity, allowing identification of a larger number of species for each sample, compared to 16S rDNA amplicon sequencing. Further comparative studies in independent samples are called for.

Efficacy of adalimumab as second-line therapy in a pediatric cohort of Crohn's disease patients who failed infliximab therapy: the Italian Society of Pediatric Gastroenterology, Hepatology, and Nutrition experience

Background

Adalimumab (Ada) treatment is an available option for pediatric Crohn’s disease (CD) and the published experience as rescue therapy is limited.

Objectives

We investigated Ada efficacy in a retrospective, pediatric CD cohort who had failed previous infliximab treatment, with a minimum follow-up of 6 months.

Methods

In this multicenter study, data on demographics, clinical activity, growth, laboratory values (CRP) and adverse events were collected from CD patients during follow-up. Clinical remission (CR) and response were defined with Pediatric CD Activity Index (PCDAI) score ≤10 and a decrease in PCDAI score of ≥12.5 from baseline, respectively.

Results

A total of 44 patients were consecutively recruited (mean age 14.8 years): 34 of 44 (77%) had active disease (mean PCDAI score 24.5) at the time of Ada administration, with a mean disease duration of 3.4 (range 0.3–11.2) years. At 6, 12, and 18 months, out of the total of the enrolled population, CR rates were 55%, 78%, and 52%, respectively, with a significant decrease in PCDAI scores (P<0.01) and mean CRP values (mean CRP 5.7 and 2.4 mL/dL, respectively; P<0.01) at the end of follow-up. Steroid-free remission rates, considered as the total number of patients in CR who were not using steroids at the end of this study, were 93%, 95%, and 96% in 44 patients at 6, 12, and 18 months, respectively. No significant differences in growth parameters were detected. In univariate analysis of variables related to Ada efficacy, we found that only a disease duration >2 years was negatively correlated with final PCDAI score (P<0.01). Two serious adverse events were recorded: 1 meningitis and 1 medulloblastoma.

Conclusion

Our data confirm Ada efficacy in pediatric patients as second-line biological therapy after infliximab failure. Longer-term prospective data are warranted to define general effectiveness and safety in pediatric CD patients.

A 12-Week Maintenance Therapy with a New Prepared Viscous Budesonide in Pediatric Eosinophilic Esophagitis

BACKGROUND

A new prepared oral viscous budesonide (PVB) has been effective in inducing clinical and histological remission in pediatric eosinophilic esophagitis (EoE).

AIMS

To evaluate the efficacy of a 12-week maintenance therapy on clinical, endoscopic, and histological remission using half of the dose used in the induction therapy.

METHODS

We prospectively enrolled pediatric patients with active EoE. After 12 weeks of induction therapy with PVB (< 150 cm: 2 mg/day; ≥ 150 cm: 4 mg/day) patients received a maintenance dose of half of the dose used in the induction therapy (1 mg or 2 mg) for another 12 weeks. A 12-week follow-up was then performed in all patients after the end of therapy. Endoscopy was performed at weeks 0, 12, 24, and 36. Symptoms, endoscopy, and histology scores were also calculated. Serum cortisol was evaluated during the treatment period.

RESULTS

We enrolled 20 children (15 males; median age 10 years; range 4-17). After the 12-week induction therapy 18 patients (90%) were in remission, with a significant decrease in the median peak of eosinophil count/HPF as well as a marked reduction in clinical, endoscopic, and histological scores (p < 0.01). At the end of the maintenance therapy (week 24), 17 patients (85%) were still in remission, while there were only 9 at week 36 (45%). No significant changes in cortisol levels were observed during the study period.

CONCLUSIONS

The 12-week maintenance treatment with the half the dose of PVB was effective in sustaining remission at week 24; however, no reduction in the rate of relapse after suspension of treatment occurred.

Transcription Factor ZNF281: A Novel Player in Intestinal Inflammation and Fibrosis

Background and aims: Recent evidences reveal the occurrence of a close relationship among epithelial to mesenchymal transition (EMT), chronic inflammation and fibrosis. ZNF281 is an EMT-inducing transcription factor (EMT-TF) involved in the regulation of pluripotency, stemness, and cancer. The aim of this study was to investigate in vitro, in vivo, and ex vivo a possible role of ZNF281 in the onset and progression of intestinal inflammation. A conceivable contribution of the protein to the development of intestinal fibrosis was also explored. Methods: Human colorectal adenocarcinoma cell line, HT29, and C57BL/6 mice were used for in vitro and in vivo studies. Mucosal biopsy specimens were taken during endoscopy from 29 pediatric patients with Crohn's disease (CD), 24 with ulcerative colitis (UC) and 16 controls. ZNF281 was knocked down by transfecting HT29 cells with 20 nM small interference RNA (siRNA) targeting ZNF281 (siZNF281). Results: We show for the first time that ZNF281 is induced upon treatment with inflammatory agents in HT29 cells, in cultured uninflamed colonic samples from CD patients and in DSS-treated mice. ZNF281 expression correlates with the disease severity degree of CD and UC patients. Silencing of ZNF281 strongly reduces both inflammatory (IL-8, IL-1beta, IL-17, IL-23) and EMT/fibrotic (SNAIL, Slug, TIMP-1, vimentin, fibronectin, and α-SMA) gene expression; besides, it abolishes the increase of extracellular-collagen level as well as the morphological modifications induced by inflammation. Conclusions: The identification of transcription factor ZNF281 as a novel player of intestinal inflammation and fibrosis allows a deeper comprehension of the pathogenetic mechanisms underlying inflammatory bowel disease (IBD) and provide a new target for their cure.

Endoscopy in Pediatric Inflammatory Bowel Disease: A Position Paper on Behalf of the Porto IBD Group of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition

Endoscopy is a central tool for the evaluation and management of inflammatory bowel disease (IBD). In the last few decades, gastrointestinal (GI) endoscopy has undergone significant technological developments including availability of pediatric-size equipment, enabling comprehensive investigation of the GI tract in children. Simultaneously, professional organization of GI experts have developed guidelines and training programs in pediatric GI endoscopy. This prompted the Porto Group on Pediatric IBD of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition to develop updated guidelines on the role of GI endoscopy in pediatric IBD, specifically taking into considerations of recent advances in the diagnosis, disease stratification, and novel therapeutic targets in these patients.

A promising medium-term follow-up of pediatric sclerosing cholangitis: Mild phenotype or early diagnosis?

AIM

Sclerosing cholangitis (SC) is a chronic cholestatic liver disease that is being increasingly diagnosed in childhood. The long-term course and prognosis of pediatric SC are poorly described.

METHODS

We reviewed data of pediatric SC patients, followed in two referral centers, during a period of up to 20 years. We aimed to evaluate long-term outcomes according to SC phenotype.

RESULTS

Among 45 patients (median age, 10.4 years; male patients, 73.4%) 29 (64.4%) were asymptomatic at presentation. Twenty patients (44%) had a concomitant inflammatory bowel disease (SC/IBD). Autoimmune features were found in 20 patients (44%). Liver biopsy showed severe fibrosis or cirrhosis in 32% of cases. Patients with SC alone had a higher rate of interface hepatitis at liver biopsy than SC/IBD patients. All children received ursodeoxycholic acid at diagnosis, and 17 received steroids and/or azathioprine. After a mean follow-up of 8.7 ± 5.6 years, all patients were alive and seven developed at least one liver-related complication. At the end of follow-up, 10 patients stopped immunosuppressants and two had no therapy. Only two patients underwent liver transplantation. Complication-free survival did not differ between SC/IBD and SC patients, but survival was longer in patients without autoimmune features.

CONCLUSIONS

In our early diagnosed cohort, the 9-year survival with native liver was better than that reported in other studies. Approximately 15% of patients developed liver-related disease complications, less than previously reported. The long-term course of SC was negatively influenced by the presence of autoimmune features, but not by concomitant IBD.

Krill oil, vitamin D and Lactobacillus reuteri cooperate to reduce gut inflammation

Current research into original therapies to treat intestinal inflammation is focusing on no-drug therapies. KLD is a mixture of krill oil (KO), probiotic Lactobacillus reuteri (LR), and vitamin D (VitD3). The aim of this study was to assess in vitro and in vivo the potential cooperative effects of KLD in reducing gut inflammation. Colorectal adenocarcinoma cell lines, CACO2 and HT29, and C57BL/6 mice were used for in vitro and in vivo analyses, respectively. Cells were exposed to cytomix (interferon gamma + tumour necrosis factor alpha (TNF-α)) to induce inflammation or co-exposed to cytomix and KO, LR and VitD3 alone or to cytomix and KLD. Animals were treated for 7 days with dextran sodium sulphate (DSS) to induce colitis or with DSS and KLD. In vitro assays: F-actin expression was analysed by immunofluorescence; scratch test and trans-epithelial electric resistance test were performed to measure wound healing; adhesion/invasion assays of adhesive and invasive Escherichia coli (AIEC) bacteria were made; mRNA expression of TNF-α, interleukin (IL)-8 and vitamin D receptor (VDR) was detected by quantitative PCR. In vivo assays: body weight, clinical score, histological score and large intestine weight and length were estimated; mRNA expression of TNF-α, IL-1β, IL-6, IL-10 by quantitative PCR; VDR expression was detected by quantitative PCR and immunohistochemistry. In vitro: KLD restores epithelial cell-cell adhesion and mucosal healing during inflammation, while decreases the adhesiveness and invasiveness of AIEC bacteria and TNF-α and IL-8 mRNA expression and increases VDR expression. In vivo: KLD significantly improves body weight, clinical score, histological score and large intestine length of mice with DSS-induced colitis and reduces TNF-α, IL-1β and IL-6 mRNA levels, while increases IL-10 mRNA and VDR levels. KLD has significant effects on the intestinal mucosa, strongly decreasing inflammation, increasing epithelial restitution and reducing pathogenicity of harmful commensal bacteria.

Safety of Oats in Children with Celiac Disease: A Double-Blind, Randomized, Placebo-Controlled Trial

OBJECTIVE

To evaluate the long-term validity and safety of pure oats in the treatment of children with celiac disease.

STUDY DESIGN

This noninferiority clinical trial used a double-blind, placebo-controlled, crossover design extended over 15 months. Three hundred six children with a biopsy-proven diagnosis of celiac disease on a gluten-free diet for ≥2 years were randomly assigned to eat specifically prepared gluten-free food containing an age-dependent amount (15-40 g) of either placebo or purified nonreactive varieties of oats for 2 consecutive 6-month periods separated by washout standard gluten-free diet for 3 months. Clinical (body mass index, Gastrointestinal Symptoms Rating Scale score), serologic (IgA antitransglutaminase antibodies, and IgA anti-avenin antibodies), and intestinal permeability data were measured at baseline, and after 6, 9, and 15 months. Direct treatment effect was evaluated by a nonparametric approach using medians (95% CI) as summary statistic.

RESULTS

After the exclusion of 129 patients who dropped out, the cohort included 177 children (79 in the oats-placebo and 98 in the placebo-oats group; median, 0.004; 95% CI, -0.0002 to 0.0089). Direct treatment effect was not statistically significant for clinical, serologic, and intestinal permeability variables (body mass index: median, -0.5; 95% CI, -0.12 to 0.00; Gastrointestinal Symptoms Rating Scale score: median, 0; 95% CI, -2.5 to 0.00; IgA antitransglutaminase antibodies: median, -0.02; 95% CI, -0.25 to 0.23; IgA anti-avenin antibodies: median, -0.0002; 95% CI, -0.0007 to 0.0003; intestinal permeability test: median, 0.004; 95% CI, -0.0002 to 0.0089).

CONCLUSIONS

Pure nonreactive oat products are a safe dietary choice in the treatment of children with celiac disease.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00808301.

NOD2 and inflammation: current insights

The nucleotide-binding oligomerization domain (NOD) protein, NOD2, belonging to the intracellular NOD-like receptor family, detects conserved motifs in bacterial peptidoglycan and promotes their clearance through activation of a proinflammatory transcriptional program and other innate immune pathways, including autophagy and endoplasmic reticulum stress. An inactive form due to mutations or a constitutive high expression of NOD2 is associated with several inflammatory diseases, suggesting that balanced NOD2 signaling is critical for the maintenance of immune homeostasis. In this review, we discuss recent developments about the pathway and mechanisms of regulation of NOD2 and illustrate the principal functions of the gene, with particular emphasis on its central role in maintaining the equilibrium between intestinal microbiota and host immune responses to control inflammation. Furthermore, we survey recent studies illustrating the role of NOD2 in several inflammatory diseases, in particular, inflammatory bowel disease, of which it is the main susceptibility gene.

Bifidobacteria and lactobacilli in the gut microbiome of children with non-alcoholic fatty liver disease: which strains act as health players?

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD), considered the leading cause of chronic liver disease in children, can often progress from non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH). It is clear that obesity is one of the main risk factors involved in NAFLD pathogenesis, even if specific mechanisms have yet to be elucidated. We investigated the distribution of intestinal bifidobacteria and lactobacilli in the stools of four groups of children: obese, obese with NAFL, obese with NASH, and healthy, age-matched controls (CTRLs).

MATERIAL AND METHODS

Sixty-one obese, NAFL and NASH children and 54 CTRLs were enrolled in the study. Anthropometric and metabolic parameters were measured for all subjects. All children with suspected NASH underwent liver biopsy. Bifidobacteria and lactobacilli were analysed in children's faecal samples, during a broader, 16S rRNA-based pyrosequencing analysis of the gut microbiome.

RESULTS

Three Bifidobacterium spp. (Bifidobacterium longum, Bifidobacterium bifidum, and Bifidobacterium adolescentis) and five Lactobacillus spp. (L. zeae, L. vaginalis, L. brevis, L. ruminis, and L. mucosae) frequently recurred in metagenomic analyses. Lactobacillus spp. increased in NAFL, NASH, or obese children compared to CTRLs. Particularly, L. mucosae was significantly higher in obese (p = 0.02426), NAFLD (p = 0.01313) and NASH (p = 0.01079) than in CTRLs. In contrast, Bifidobacterium spp. were more abundant in CTRLs, suggesting a protective and beneficial role of these microorganisms against the aforementioned diseases.

CONCLUSIONS

Bifidobacteria seem to have a protective role against the development of NAFLD and obesity, highlighting their possible use in developing novel, targeted and effective probiotics.

Serum Markers of Necrotizing Enterocolitis: A Systematic Review

OBJECTIVE

The aim of the study was to systematically review the diagnostic utility of serum biomarkers for the diagnosis of necrotizing enterocolitis (NEC).

METHODS

We conducted an electronic and manual search of the available evidence. We included studies reporting data on the diagnostic accuracy of "serum" biomarkers for the diagnosis of NEC, available until January 2016.

RESULTS

We selected 22 studies from the 1296 articles retrieved. Only S100 A8/A9 protein and apolipoprotein-CII showed high sensitivity (100% and 96.4%, respectively) and specificity (90% and 95%, respectively) in the studies using Bell stage II NEC as target condition. High sensitivity and specificity were reported for interleukin-10 (100% and 90%), interleukin1-receptor antagonist (100% and 91.7%), intestinal fatty acid-binding protein (100% and 91%) and ischemia-modified albumin (94.7% and 92%), when tested to predict the evolution from definite to advanced NEC. Given the amount of uncertainty, the limited availability of data and heterogeneity among the populations in the different studies, we were unable to perform a meta-analysis. Major concerns about the applicability stemmed from the spectrum of patients enrolled and the inclusion of diseases different from Bell stage ≥2 NEC as target conditions.

CONCLUSIONS

We identified only few markers with good diagnostic accuracy and found an overall low quality of the studies on serum NEC biomarkers. In conclusion, data supporting their use are insufficient.

RIP3 AND pMLKL promote necroptosis-induced inflammation and alter membrane permeability in intestinal epithelial cells

BACKGROUND

Necroptosis is an inflammatory form of programmed cell death requiring receptor-interacting protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL).

AIMS

The aim of this study is to examine in depth in vitro and ex vivo the contribution of necroptosis to intestinal inflammation.

METHODS

In vitro: we used an intestinal cell line, HCT116RIP3, produced in our laboratory and overexpressing RIP3. Ex vivo: intestinal mucosal biopsies were taken from patients with inflammatory bowel disease (IBD) (20 with Crohn's disease; 20 with ulcerative colitis) and from 20 controls.

RESULTS

RIP3-induced necroptosis triggers MLKL activation, increases cytokine/alarmin expression (IL-8, IL-1β, IL-33, HMGB1), NF-kBp65 translocation and NALP3 inflammasome assembly. It also affects membrane permeability by altering cell-cell junctional proteins (E-cadherin, Occludin, Zonulin-1). Targeting necroptosis through Necrostatin-1 significantly reduces intestinal inflammation in vitro and in cultured intestinal explants from IBD.

CONCLUSION

We show for the first time in vitro and ex vivo that RIP3-driven necroptosis seriously affects intestinal inflammation by increasing pMLKL, activating different cytokines and alarmins, and altering epithelial permeability. The inhibition of necroptosis causes a significant decrease of all these effects. These data strongly support the view that targeting necroptosis may represent a promising new option for the treatment of inflammatory enteropathies.

Development and Validation of Diagnostic Criteria for IBD Subtypes Including IBD-unclassified in Children: a Multicentre Study From the Pediatric IBD Porto Group of ESPGHAN

BACKGROUND

The revised Porto criteria identify subtypes of paediatric inflammatory bowel diseases: ulcerative colitis [UC], atypical UC, inflammatory bowel disease unclassified [IBDU], and Crohn's disease [CD]. Others have proposed another subclassifiction of Crohn's colitis. In continuation of the Porto criteria, we aimed to derive and validate criteria, termed "PIBD-classes," for standardising the classification of the different IBD subtypes.

METHODS

This was a multicentre retrospective longitudinal study from 23 centres affiliated with the Port -group of ESPGHAN. Both a hypothesis-driven judgmental approach and mathematical classification and regression tree [CART] modelling were used for creating a diagnostic algorithm. Since small bowel inflammation is easily recognised as CD, we focused here primarily on the phenotype of colitis.

RESULTS

In all, 749 IBD children were enrolled: 236 [32%] Crohn's colitis, 272 [36%] UC and 241 [32%] IBDU [age 10.9 ± 3.6 years] with a median follow-up of 2.8 years (interquartile range [IQR] 1.7-4.3). A total of 23 features were clustered in three classes according to their prevalence in UC: six class-1 features [0% prevalence in UC], 12 class-2 features [< 5% prevalence], and five class-3 features [5-10% prevalence]. According to the algorithm, the disease should be classified as UC if no features exist in any of the classes. When at least one feature exists, different combinations classify the disease into atypical UC, IBDU or CD. The algorithm differentiated UC from CD and IBDU with 80% sensitivity (95% confidence interval [CI] 71-88%) and 84% specificity [77-89%], and CD from IBDU and UC with 78% sensitivity [67-87%] and 94% specificity [89-97%].

CONCLUSIONS

The validated PIBD-classes algorithm can adequately classify children with IBD into small bowel CD, colonic CD, IBDU, atypical UC, and UC.

European Crohn's and Colitis Organisation Topical Review on Transitional Care in Inflammatory Bowel Disease

BACKGROUND

This European Crohn's and Colitis Organisation [ECCO] topical review focuses on the transition of adolescents with inflammatory bowel disease [IBD] from child-centred to adult-oriented care. The aim was to provide evidence-supported, expert consensus for health professionals taking part in the transition.

METHODS

An online survey determined the areas of importance for health professionals involved in the transition of adolescents with IBD. Thereafter an expert panel of nine paediatric and five adult gastroenterologists was formed to identify the critical elements of the transition programme, and to prepare core messages defined as 'current practice points'. There is limited literature about transition, therefore this review is mainly based on expert opinion and consensus, rather than on specific evidence.

RESULTS

A total of 21 practice points were generated before the first [online] voting round. Practice points that reached >80% agreement were accepted, while those that did not reach 80% agreement were refined during a consensus meeting and subjected to voting. Ultimately, 14 practice points were retained by this review.

CONCLUSION

We present a consensus-based framework for transitional care in IBD that provides a guidance for clinical practice.

Enteral nutrition in pediatric intestinal failure: does initial feeding impact on intestinal adaptation?

Primary IF can be due to impaired gut length or impaired gut function; short bowel syndrome (SBS) is the leading cause of IF. In IF patients complete enteral starvation should be avoided whenever possible and enteral/oral nutrition (EN/ON) should be employed at the maximum tolerated amount in each phase of the clinical evolution of IF. Intraluminal nutrients have stimulatory effects on epithelial cells and on trophism that enhance intestinal adaptation. Areas covered: Evidence for nutritional interventions in pediatric IF is limited and of poor quality. Clinical practice in SBS feeding are more 'experience-based' rather than 'evidence-based' and this dearth of clinical evidence is partly due to the rarity of this condition. This review updates knowledge concerning the impact of the initial diet with EN/ON in neonatal onset SBS in the process of bowel adaption. Expert commentary: Human milk resulted the preferred starting diet and it is generally combined with amino-acids (AAs) in Northern America and with hydrolyzed proteins (HFs) in Europe; polymeric diet is rarely employed. HFs were not more effective than AAs in promoting intestinal adaptation.