Characterization of patient-derived intestinal organoids for modelling fibrosis in Inflammatory Bowel Disease.

BACKGROUND AND AIMS: Intestinal fibrosis is a common complication of Inflammatory Bowel Disease (IBD), namely Crohn's disease (CD) and ulcerative colitis (UC), but the precise mechanism by which it occurs is incompletely understood hampering the development of effective therapeutic strategies. Here, we aimed at inducing and characterizing an inflammation-mediated fibrosis in patient-derived organoids (PDOs) issued from crypts isolated from colonic mucosal biopsies of IBD pediatric patients and age matched-control subjects (CTRLs). METHODS: Inflammatory-driven fibrosis was induced by exposing CTRL-, CD- and UC-PDOs to the pro-inflammatory cytokine TNF-α for one day, followed by a co-treatment with TNF-α and TGF-ß1 for three days. Fibrotic response was proven by analyzing inflammatory and fibrotic markers by RT-qPCR and immunofluorescence. Transcriptomic changes were assessed by RNA-sequencing. RESULTS: Co-treatment with TNF-α and TGF-ß1 caused in CTRL- and IBD-PDOs morphological changes towards a mesenchymal-like phenotype and up-regulation of inflammatory, mesenchymal, and fibrotic markers. Transcriptomic profiling highlighted that in all intestinal PDOs, regardless of the disease, the co-exposure to TNF-α and TGF-ß1 regulated EMT genes and specifically increased genes involved in positive regulation of cell migration. Finally, we demonstrated that CD-PDOs display a specific response to fibrosis compared to both CTRL- and UC-PDOs, mainly characterized by upregulation of nuclear factors controlling transcription. CONCLUSIONS: This study demonstrates that intestinal PDOs may develop an inflammatory-derived fibrosis thus representing a promising tool to study fibrogenesis in IBD. Fibrotic PDOs show increased expression of EMT genes. In particular, fibrotic CD-PDOs display a specific gene expression signature compared to UC and CTRL-PDOs.

Microbiome signatures of progression toward celiac disease onset in at-risk children in a longitudinal prospective cohort study.

Other than exposure to gluten and genetic compatibility, the gut microbiome has been suggested to be involved in celiac disease (CD) pathogenesis by mediating interactions between gluten/environmental factors and the host immune system. However, to establish disease progression markers, it is essential to assess alterations in the gut microbiota before disease onset. Here, a prospective metagenomic analysis of the gut microbiota of infants at risk of CD was done to track shifts in the microbiota before CD development. We performed cross-sectional and longitudinal analyses of gut microbiota, functional pathways, and metabolites, starting from 18 mo before CD onset, in 10 infants who developed CD and 10 matched nonaffected infants. Cross-sectional analysis at CD onset identified altered abundance of six microbial strains and several metabolites between cases and controls but no change in microbial species or pathway abundance. Conversely, results of longitudinal analysis revealed several microbial species/strains/pathways/metabolites occurring in increased abundance and detected before CD onset. These had previously been linked to autoimmune and inflammatory conditions (e.g., Dialister invisus, Parabacteroides sp., Lachnospiraceae, tryptophan metabolism, and metabolites serine and threonine). Others occurred in decreased abundance before CD onset and are known to have anti-inflammatory effects (e.g., Streptococcus thermophilus, Faecalibacterium prausnitzii, and Clostridium clostridioforme). Additionally, we uncovered previously unreported microbes/pathways/metabolites (e.g., Porphyromonas sp., high mannose-type N-glycan biosynthesis, and serine) that point to CD-specific biomarkers. Our study establishes a road map for prospective longitudinal study designs to better understand the role of gut microbiota in disease pathogenesis and therapeutic targets to reestablish tolerance and/or prevent autoimmunity.

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.

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.

ZNF281 Promotes Colon Fibroblast Activation in TGFß1-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 TGFß1. ZNF281 was downregulated by siRNA transfection, and RNA-sequencing was performed to identify genes regulated by TGFß1 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 TGFß1. Moreover, abrogation of ZNF281 in TGFß1-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.

Diagnostic Value of Persistently Low Positive TGA-IgA Titers in Symptomatic Children With Suspected Celiac Disease.

OBJECTIVES: While the algorithm to diagnose celiac disease (CD) in children with elevated anti-transglutaminase IgA (TGA-IgA) titers (>10 times upper limit of normal, ULN) is well defined, the management of children with low TGA-IgA values represents a clinical challenge. We aimed to identify the diagnostic value of persistently low positive TGA-IgA titers in predicting CD in children. METHODS: We retrospectively analyzed children with symptoms or signs of CD, not eligible for a no-biopsy approach. We included children with at least 2 TGA-IgA measurements, endomysial antibody (EMA) assessment and esophagogastroduodenoscopy with biopsies. TGA-IgA values were provided as multiples of ULN. Patients were classified in groups according to median TGA-IgA values: A (TGA-IgA>1 ≤ 5 × ULN; defined as "low-positive"), B (TGA-IgA > 5 < 10 × ULN; "moderate-positive"), and C (controls). RESULTS: Data of 281 children were analyzed. Of 162 children in group A, CD was diagnosed in 142 (87.7%), whereas normal duodenal mucosa was found in 20. In group B, all 62 children (100%) received a CD diagnosis. Group C included 57 controls. EMA were undetectable in 31 (15%) of mucosal atrophy cases. On the receiver-operating characteristic curve (area under the curve = 0.910), a mean value of 1.7 ULN showed a sensitivity of 81.4% and specificity of 81.8% to predict mucosal damage. CONCLUSIONS: Repeated low or moderate TGA-IgA values (<5 ULN or <10 ULN) are good predictors of a CD diagnosis. Symptomatic children with persistently low positive TGA-IgA titers should undergo esophagogastroduodenoscopy regardless of their EMA status.

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.

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.

Intestinal Inflammation Alters the Expression of Hepatic Bile Acid Receptors Causing Liver Impairment.

OBJECTIVES: The gut-liver axis has been recently investigated in depth in relation to intestinal and hepatic diseases. Key actors are bile acid (BA) receptors, as farnesoid-X-receptor (FXR), pregnane-X-receptor (PXR), and G-protein-coupled-receptor (GPCR; TGR5), that control a broad range of metabolic processes as well as inflammation and fibrosis. The present study aims to investigate the impact of intestinal inflammation on liver health with a focus on FXR, PXR, and TGR5 expression. The strategy to improve liver health by reducing gut inflammation is also considered. Modulation of BA receptors in the inflamed colonic tissues of inflammatory bowel disease (IBD) pediatric patients is analyzed. METHODS: A dextran sodium sulphate (DSS) colitis animal model was built. Co-cultures with Caco2 and HepG2 cell lines were set up. Modulation of BA receptors in biopsies of IBD pediatric patients was assessed by real-time PCR and immunohistochemistry. RESULTS: Histology showed inflammatory cell infiltration in the liver of DSS mice, where FXR and PXR were significantly decreased and oxidative stress was increased. Exposure of Caco2 to inflammatory stimuli resulted in the reduction of BA receptor expression in HepG2. Caco2 treatment with dipotassium glycyrrhizate (DPG) reduced these effects on liver cells. Inflamed colon of patients showed altered FXR, PXR, and TGR5 expression. CONCLUSIONS: This study strongly suggests that gut inflammation affects hepatic cells by altering BA receptor levels as well as increasing the production of pro-inflammatory cytokines and oxidative stress. Hence, reducing gut inflammation is needed not only to improve the intestinal disease but also to protect the liver.

Paradoxical Psoriasis Induced by Anti-TNFα Treatment: Evaluation of Disease-Specific Clinical and Genetic Markers.

Paradoxical psoriasis (PP) may occur during treatment with anti-tumor necrosis factor-alpha (TNF-α) drugs in various chronic immune-mediated diseases, mainly inflammatory bowel diseases (IBD) and psoriasis. In this study, clinical and genetic characteristics of PP arising in IBD and psoriatic patients were investigated to identify disease-specific markers of the paradoxical effect. A total of 161 IBD and psoriatic patients treated with anti-TNF-α drugs were included in the study. Of these patients, 39 developed PP. All patients were characterized for the main clinical-pathologic characteristics and genotyped for six candidate single nucleotide polymorphisms (SNPs) selected for their possible role in PP susceptibility. In IBD patients, the onset of PP was associated with female sex, presence of comorbidities, and use of adalimumab. IBD patients with PP had a higher frequency of the TNF-α rs1799964 rare allele (p = 0.006) compared with cases without the paradoxical effect, and a lower frequency of the human leucocyte antigen (HLA)-Cw06 rs10484554 rare allele (p = 0.03) compared with psoriatic patients with PP. Overall, these findings point to specific clinical and genetic characteristics of IBD patients with PP and provide data showing that genetic variability may be related to the paradoxical effect of anti-TNF-α drugs with possible implications into clinical practice.

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.

MRI reveals different Crohn's disease phenotypes in children and adults.

OBJECTIVES: To identify differences between two cohorts of adult and pediatric patients affected by Crohn's disease (CD), with regard to lesion location in the small intestine and colon-rectum, lesion activity, and prevalence of perianal disease (PD), using MRI as the main diagnostic tool. METHODS: We retrospectively reviewed 350 consecutive MRI examinations performed between 2013 and 2016 in outpatients or inpatients with histologically proven CD, monitored by the Gastroenterology and Pediatric Units of our Hospital. The magnetic resonance enterography (MRE) protocol for adult and pediatric CD patients routinely includes evaluation of nine different intestinal segments (from jejunum to rectum) and of the anal canal. Intestinal activity was also calculated using a validated score. Perianal disease (PD) was staged. Fisher's exact test was used and the odds ratio (OR) was calculated. RESULTS: Two hundred and nineteen out of 350 MRI studies (118 adults and 101 children) were included. The prevalence of PD was 34.6% in children and 16.1% in adults (OR = 2.8; p = 0.0017). Pediatric patients showed more frequent rectal involvement (29.7% vs 13.5%, OR = 2.7; p = 0.0045) and higher risk of PD in the presence of rectal disease (p = 0.043; OR = 4.5). In pediatric patients with severe colorectal disease, the prevalence of PD was twofold (86.7% vs 40%; p = 0.072). Using the clinical Montreal classification for lesion location, no significant differences emerged between the two patient populations. CONCLUSIONS: MRI showed a significantly higher prevalence of rectal involvement and perianal disease in the pediatric population. These results may have a relevant clinical impact and deserve further investigation. KEY POINTS: • To our knowledge, this is the largest morphological comparative study available in the literature using MRI as the main diagnostic tool to compare adult patients and children with Crohn's disease. • Our study showed significant differences between adults and children: a higher prevalence of rectal and perianal fistulous disease (PD) in pediatric patients and an increased prevalence of PD in the presence of severe colon-rectum involvement. • The association of rectal and perianal disease implies a poorer clinical prognosis and a higher risk of disabling complications in pediatric patients.

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.

Predictors of Long-term Clinical and Endoscopic Remission in Children With Crohn Disease Treated With Infliximab.

OBJECTIVES: We aimed to identify early noninvasive predictors of clinical and endoscopic remission in children with Crohn disease (CD) under infliximab (IFX). METHODS: Prospective observational study conducted in children with moderate-to-severe CD starting IFX. All patients underwent weighted pediatric CD activity index (wPCDAI) assessment, C-reactive protein and fecal calprotectin (FC) at week 0, 14, and 48. Endoscopy was performed at 0 and 48 weeks. The primary outcome was to determine the ability of 14-week wPCDAI, C-reactive protein, and FC to predict 1-year steroid-free clinical remission and mucosal healing. As a secondary outcome we evaluated their concordance with Simple Endoscopic Score for CD (SES-CD) at week 48. RESULTS: Forty-one children were enrolled. At 1 year, 21 (51%) and 16 (39%) were in clinical and endoscopic remission. Only combined postinduction FC and wPCDAI were able to predict 1-year clinical and endoscopic remission (hazard ratio 4.81 [95% confidence interval 1.76-20.45], P = 0.05 and hazard ratio 5.51 [95% confidence interval 1.83-26.9], P = 0.03). One-year SES-CD moderately correlated with FC (r = 0.52; P = 0.001). The FC cut-off value for mucosal healing was 120.5 µg/g (area under the curve 0.863, 83% sensitivity, 75.5% specificity; P = 0.005). The concordance between wPCDAI and SES-CD was excellent and good for severe disease and remission (k 0.87 and 0.76). CONCLUSIONS: Post induction FC combined with wPCDAI can predict 1-year clinical and endoscopic response to IFX in pediatric CD. FC shows a moderate correlation with SES-CD, whereas wPCDAI has a good concordance with endoscopic remission or severe disease, but not with mild and moderate disease.

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.

Infliximab Is Not Associated With Increased Risk of Malignancy or Hemophagocytic Lymphohistiocytosis in Pediatric Patients With Inflammatory Bowel Disease.

BACKGROUND AND AIMS: Immunosuppressive therapy for inflammatory bowel disease (IBD) in pediatric patients is thought to increase the risk of malignancy and lymphoproliferative disorders, including hemophagocytic lymphohistiocytosis (HLH). We compared unadjusted incidence rates of malignancy and HLH in pediatric patients with IBD exposed to infliximab (IFX) with patients not exposed to biologics and calculated standardized incidence ratios (SIRs). METHODS: We collected and analyzed data from 5766 participants in a prospective study of long-term outcomes of pediatric patients with IBD (NCT00606346), from May 31, 2007 through June 30, 2016. Patients were 17 years old or younger and had Crohn's disease, ulcerative colitis, or IBD-unclassified with 24,543.0 patient-years of follow-up. We estimated incidence rates for malignancy and HLH as events/1000 patient-years of follow-up. We calculated age-, sex-, and race-adjusted SIRs, with 95% confidence intervals (CIs), using the Surveillance, Epidemiology, and End Results Program (SEER) database. RESULTS: Thirteen of the 15 patients who developed a malignancy and all 5 of the patients who developed HLH had been exposed to thiopurines; 10 patients with malignancy had also been exposed to a biologic agent. Unadjusted incidence rates showed no increased risk of malignancy (0.46/1000 patient-years) or HLH (0.0/1000 patient-years) in patients exposed to IFX as the only biologic vs those unexposed to biologics (malignancy: 1.12/1000 patient-years; HLH: 0.56/1000 patient-years). SIRs did not demonstrate an increased risk of malignancy among patients exposed to IFX (SIR, 1.69; 95% CI, 0.46-4.32) vs patients not exposed to a biologic agent (SIR, 2.17; 95% CI, 0.59-5.56), even when patients were stratified by thiopurine exposure. CONCLUSIONS: In determination of age-, sex-, and race-adjusted SIRs using data from a large clinical study and the SEER database, we found that IFX exposure did not associate with increased risk of malignancy or HLH in pediatric patients with IBD. Thiopurine exposure is an important precedent event for the development of malignancy or HLH in pediatric patients with IBD.

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.

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.

Efficacy and Safety of Adalimumab in Pediatric Ulcerative Colitis: A Real-life Experience from the SIGENP-IBD Registry.

OBJECTIVES: The aim of this study was to evaluate the effectiveness and safety of adalimumab (ADA) in children with ulcerative colitis (UC) previously treated with infliximab (IFX). METHODS: Retrospective study including children with UC from a national registry who received ADA therapy. The primary endpoint was the rate of corticosteroid-free remission at week 52. Secondary outcomes were the rate of sustained clinical remission, primary nonresponse, and loss of response at weeks 12, 30, and 52 and rate of mucosal healing and side effects at week 52. RESULTS: Thirty-two children received ADA (median age 10 ±â€Š4 years). Median disease duration before ADA therapy was 27 months. All patients received previous IFX (43% intolerant, 50% nonresponders [37.5% primary, 42.5% secondary nonresponders], 6.7% positive anti-IFX antibodies). Fifty-two weeks after ADA initiation, 13 patients (41%) were in corticosteroid-free remission. Mucosal healing occurred in 9 patients (28%) at 52 weeks. The cumulative probability of a clinical relapse-free course was 69%, 59%, and 53% at 12, 30, and 52 weeks, respectively. Ten patients (31%) had a primary failure and 5 (15%) a loss of response to ADA. No significant differences in efficacy were reported between not-responders and intolerant to IFX (P = 1.0). Overall, 19 patient (59%) maintained ADA during 52-week follow-up. Seven patients (22%) experienced an adverse event, no serious side effects were observed and none resulted in ADA discontinuation. CONCLUSIONS: Based on our data, ADA seems to be effective in children with UC, allowing to recover a significant percentage of patients intolerant or not-responding to IFX. The safety profile was good.

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.