Inflammatory Bowel Disease in Children and Adolescents

Bile acid alterations associated with indolent course of inflammatory bowel disease

BACKGROUND

The indolent course of treatment-naive patients with inflammatory bowel disease (IBD) is confirmed predictable based on clinical characteristics. Current evidences supported that bile acids (BAs) alteration might be promising biomarkers in the field of IBD. We aimed to analyze the alterations of BAs as the disease progresses and explore their predictive value for indolent course of IBD.

METHODS

The indolent course of IBD was defined as a disease course without need for strict interventions throughout the entire follow-up. A targeted metabolomics method was used to detect the concentration of 27 BAs from serum sample in treatment-naive patients with IBD (Crohn's disease [CD], n = 27; ulcerative colitis [UC], n = 50). Patients with CD and UC were individually divided into two groups for further study according to the median time of indolent course. The overall BAs profile and the clinical value of BAs in predicting indolent course of IBD were identified between different groups.

RESULTS

For CD, the levels of deoxycholic acid, glycodeoxycholic acid, taurodeoxycholic acid, glycolithocholic acid-3-sulfate disodium salt and iso-lithocholic acid were significantly increased in patients with indolent course > 18 M (p < 0.05). These five BAs owned 83.5% accuracy for predicting indolent course over 18 months in CD. For UC, the concentration of deoxycholic acid and glycodeoxycholic acid were significantly higher, while dehydrocholic acid were lower in patients with indolent course > 48 M (p < 0.05). These three BAs predicted indolent course over 48 months of 69.8% accuracy in UC.

CONCLUSION

The specific BAs alterations might be potential biomarkers in predicting disease course of IBD patients.

Pediatric IBD patients show medication and disease activity dependent changes in NK cell and CD4 memory T cell populations

Objectives

CD4+ memory T cells facilitate long-termed adaptive immune responses while NK cells are predominately rapid effector cells with significant functions for both intestinal homeostasis and inflammation. We wanted to study both populations in health and pediatric inflammatory bowel disease (IBD) and correlate them with disease activity and medication.

Methods

We performed flow cytometric analyses of peripheral blood CD4 + CD45RO+ memory T cells and CD3-CD16 + CD56+ NK cells in 30 patients with IBD and 31 age-matched controls and correlated percentages of subsets with disease activity (PUCAI/PCDAI) and medication.

Results

We found a significant reduction of peripheral NK cells in overall IBD patients with both clinical remission and disease activity, which was even more pronounced in patients treated with azathioprine. Otherwise, circulating CD4+ memory T cell populations were significantly enhanced in active IBD compared to controls. Enhancement of memory T cells was particularly found in new onset disease and correlated with disease activity scores.

Discussion

Our single center cohort confirms previous results showing enhanced memory T cell populations in pediatric IBD patients, which correlate with disease activity scores. CD4+ memory T cells are a relevant pathogenic leukocyte population for disease development and perpetuation in IBD. In addition, we found a decrease of NK cells in IBD patients, which was pronounced by use of azathioprine. Surveillance of both cellular populations could possibly serve as biomarker for therapy control in pediatric IBD.

Efficacy of Crohn's disease exclusion diet in treatment -naïve children and children progressed on biological therapy: a retrospective chart review

BACKGROUND

Recent trials suggested that the Crohn's disease (CD) exclusion diet (CDED) plus partial enteral nutrition (PEN) is a safe and effective strategy in remission induction of paediatric-onset CD. However, real-world evidence regarding the safety and efficacy of the CDED plus PEN approach is still lacking. The present case-series study reported our experience with the outcomes of CDED plus PEN in the paediatric-onset CD at disease onset and after the loss of response to biologics.

METHODS

We conducted a retrospective chart review on children who were treated with CDED plus PEN through the period from July 2019 and December 2020. Clinical and laboratory data were retrieved and compared at baseline, 6, 12, and 24 weeks of treatment. The primary endpoint of the present study was the rate of clinical remission.

RESULTS

The present study retrieved the data from 15 patients. Of them, nine patients were treatment naïve at the time of initiation of CDED plus PEN (group A) and the remaining patients relapsed on biologics before treatment. All patients in groups A and B exhibited clinical remission in week six, which was sustained until week 12. At the end of the follow-up, the clinical remission rate was 87% and 60% in groups A and B, respectively. No side effects were observed in both groups. In group A, the faecal calprotectin (FC) and albumin improved at week six, week 12, and week 24 (p < 0.05). The erythrocyte sedimentation rate (ESR) improved significantly at week 12 (p = 0.021) and week 24 (p = 0.027). At the same time, the haemoglobin and iron levels showed significant improvement only at week 24. For group B, only FC showed numerical reductions over time that did not reach the level of statistical significance.

CONCLUSION

Treatment with CDED plus PEN was well tolerated and achieved an excellent clinical remission rate in treatment-naive patients. However, the benefit of CDED plus PEN was less in patients who initiated the strategy after losing the response to biologics.

Tumour necrosis factor (TNF) antagonist therapy for paediatric inflammatory bowel disease: A systematic review

Inflammatory bowel disease includes two chronic inflammatory diseases, ulcerative colitis and Crohn's disease. The burden of disease is increasing worldwide. A few reviews evaluating the paediatric use of tumour necrosis factor (TNF) antagonists have been published, although these mostly include observational studies and do not consider economic evaluations. This systematic review evaluated the available evidence regarding the efficacy, safety, and cost-effectiveness of TNF antagonist therapy for paediatric inflammatory bowel disease. We searched PubMed/MEDLINE, Embase, and Cochrane Central (up to May 2022). Nine randomized clinical trials and four economic evaluations that examined any anti-TNF drugs (e.g., infliximab, adalimumab, golimumab, and certolizumab) against different alternatives were included. In studies evaluating the efficacy of anti-TNF drugs in Crohn's disease, most assessed the efficacy of maintenance regimen in patients who had previously responded to induction (response=28%-63%, and clinical remission=17%-83% depending on dose, drug, and follow-up). In ulcerative colitis, maintenance treatment with anti-TNF drugs reported clinical remission rates between 17% and 44%. Nine studies reported information on adverse events. No clinical trials comparing different anti-TNF drugs were found. The findings from this review suggest that maintenance treatment with anti-TNF drugs (such as infliximab and adalimumab) in paediatric inflammatory bowel disease is probably effective and safe. However, the economic evaluations reported contradictory results of the cost-effectiveness ratios. Protocol registry: Open Science Framework: https://osf.io/wjmvf.

Epidemiology, validation, and clinical characteristics of inflammatory bowel disease: the ABIS birth cohort study

BACKGROUND

Birth cohort studies with linked register-based data on inflammatory bowel disease (IBD) provide opportunities to prospectively study early-life determinants of the disease. However, register-based data often lack information on clinical characteristics and rely on diagnostic algorithms. Within the All Babies in Southeast Sweden (ABIS) cohort, we examined the validity of a register-based definition of IBD, its incidence, and clinical and therapeutic characteristics at diagnosis.

METHODS

We followed 16,223 children from birth (1997-1999) until the end of 2020 for the diagnosis of IBD as defined by a minimum of two diagnostic codes for IBD in the Swedish National Patient Register (NPR). We described the incidence and cumulative incidence of IBD. Through a medical record review of cases diagnosed by the end of 2017, we examined the positive predictive value (PPV) for IBD and described its clinical characteristics and treatment.

RESULTS

By 2020, at an average age of 22.2 years, 113 participants (0.74%, 95% confidence interval [CI] = 0.61-0.89) had a register-based diagnosis of IBD, corresponding to an incidence of 31.3 per 100,000 person-years of follow-up; the incidence for Crohn's disease (CD) was 11.1 per 100,000 person-years and 15.8 for ulcerative colitis (UC). Of 77 participants with a register-based definition of IBD by the end of 2017, medical records were identified for 61 participants, of whom 57 had true IBD (PPV = 93%; 95%CI = 0.87-1.00). While oral 5-aminosalicylic acid treatment was equally common in newly diagnosed CD and UC patients, biologics were more often used for newly diagnosed CD. The median faecal calprotectin levels were 1206 mg/kg at diagnosis and 93 mg/kg at the last follow-up (P < 0.001).

CONCLUSIONS

In this population-based sample of Swedish children and young adults the cumulative IBD incidence was 0.74. The validity of register-based definition of IBD was high and supports using such data to identify IBD patients in cohort studies.

Meningococcal ACWY conjugate vaccine immunogenicity and safety in adolescents with juvenile idiopathic arthritis and inflammatory bowel disease: A prospective observational cohort study

BACKGROUND

Immunogenicity to meningococcal serogroup ACWY (MenACWY) conjugate vaccine has not been studied in immunocompromised minors with juvenile idiopathic arthritis (JIA) or inflammatory bowel disease (IBD). We determined immunogenicity of a MenACWY-TT vaccine in JIA and IBD patients at adolescent age and compared results to data from aged-matched healthy controls (HCs).

METHODS

We performed a prospective observational cohort study in JIA and IBD patients (14-18 years old), who received a MenACWY vaccination during a nationwide catch-up campaign (2018-2019) in the Netherlands. Primary aim was to compare MenACWY polysaccharide-specific serum IgG geometric mean concentrations (GMCs) in patients with HCs and secondary between patients with or without anti-TNF therapy. GMCs were determined before and 3-6, 12, and 24 months postvaccination and compared with data from HCs at baseline and 12 months postvaccination. Serum bactericidal antibody (SBA) titers were determined in a subset of patients at 12 months postvaccination.

RESULTS

We included 226 JIA and IBD patients (66 % and 34 % respectively). GMCs were lower for MenA and MenW (GMC ratio 0·24 [0·17-0·34] and 0·16 [0·10-0·26] respectively, p < 0·01) in patients compared to HCs at 12 months postvaccination. Anti-TNF users had lower MenACWY GMCs postvaccination compared with those without anti-TNF (p < 0·01). The proportion protected (SBA ≥ 8) for MenW was reduced in anti-TNF users (76 % versus 92 % in non-anti-TNF and 100 % in HCs, p < 0.01).

CONCLUSION

The MenACWY conjugate vaccine was immunogenic in the vast majority of JIA and IBD patients at adolescent age, but seroprotection was lower in patients using anti-TNF agents. Therefore, an extra booster MenACWY vaccination should be considered.

Efficacy and safety of vedolizumab in the treatment of patients with inflammatory bowel disease: A systematic review and meta‑analysis of randomized controlled trials

Few studies have thoroughly assessed the efficacy and safety of vedolizumab (VDZ) in the treatment of inflammatory bowel disease (IBD). Therefore, this systematic review and meta-analysis was performed to further evaluate this association. PubMed, Embase, and the Cochrane databases were searched until April 2022. Randomized controlled trials (RCTs) evaluating the efficacy and safety of VDZ in the treatment of IBD were included. The risk ratio (RR) and 95% confidence intervals (CI) were estimated for each outcome using a random effects model. A total of 12 RCTs, including 4,865 patients, met the inclusion criteria. In the induction phase, VDZ was more effective than placebo for patients with ulcerative colitis and Crohn's disease (CD) in clinical remission (RR=2.09; 95% CI=1.66-2.62) and clinical response (RR=1.54; 95% CI=1.34-1.78). In the maintenance therapy group, VDZ reached higher clinical remission (RR=1.98; 95% CI=1.58-2.49) and clinical response (RR=1.78; 95% CI=1.40-2.26) rates compared with the placebo group. VDZ particularly improved clinical remission (RR=2.07; 95% CI=1.48-2.89) and clinical response (RR=1.84; 95% CI=1.54-2.21) in patients with TNF antagonist failure. In terms of corticosteroid-free remission, VDZ was also more effective than placebo in patients with IBD (RR=1.98; 95% CI=1.51-2.59). In Crohn's patients, VDZ was more effective than placebo in terms of mucosal healing (RR=1.78; 95% CI=1.27-2.51). With respect to adverse events, VDZ significantly reduced the risk of IBD exacerbation compared with the placebo (RR=0.60; 95% CI=0.39-0.93; P=0.023). However, when compared with the placebo, VDZ increased the risk of nasopharyngitis in patients with CD (RR=1.77; 95% CI=1.01-3.10; P=0.045). No significant differences in other adverse events were observed. Although there might be underlying risk, such as selection bias, in the present study it can be safely concluded that VDZ is a safe and effective biological agent for IBD, particularly for patients with TNF antagonist failure.

Outcomes for Standardized Home and Hospital-Based Infusions of Infliximab for Children With Inflammatory Bowel Disease

BACKGROUND

Pediatric inflammatory bowel disease (IBD) is commonly treated with infliximab in a hospital setting. Utilization of home infusions (HI) is increasing due to insurance mandates, travel time savings, and convenience. We evaluated adverse outcomes (AOs) of infliximab infusions in children with IBD receiving HI compared to hospital-based infusions.

METHODS

Children receiving HI between September 2016 and September 2018 were retrospectively matched based on age, race, ethnicity, sex, and disease type to a cohort receiving infliximab at a hospital-based center. A survival analysis evaluated the hazard ratio for AOs in HI relative to hospital-infused children over 2 years. AOs were defined as discontinuation of therapy for clinically relevant reasons, IBD-related hospitalizations, and emergency department visits.

RESULTS

We included 102 children (51 pairs) (63% male, 91% White, 92% Crohn disease). Disease location, behavior, growth status, and disease severity were similar between the 2 cohorts. Quiescent disease increased from 3% to 93% after 2 years without cohort differences. At baseline, 94% of HI patients and 88% of controls were on 5 mg/kg every 8 weeks as standard maintenance therapy. Within 2 years, only 19% remained on 5 mg/kg and the remainder required increased dosing or decreased interval. The HI cohort had fewer labs obtained ( P < 0.001), though laboratory values, number of clinic visits, and frequency of AOs were similar.

CONCLUSION

Drug durability, AOs, and laboratory values were similar between HI and hospital-based infusions. These findings suggest HI may be as effective as hospital-based infusions, provided a standardized care approach is utilized.

Physical Fitness and Inflammatory Bowel Disease Risk Among Children and Adolescents in Taiwan

Importance

The incidence of inflammatory bowel disease (IBD) is increasing in newly industrialized countries but disease etiologies remain unclear.

Objective

To investigate the association between physical fitness and subsequent IBD risk among children and adolescents in Taiwan.

Design, Setting, and Participants

This nationwide cohort study was conducted between January 1, 2010, and December 31, 2018. Data sources included the Taiwan National Health Insurance Research Database, the National Student Fitness Tests Database, and the Air Quality Monitoring System Database. This study included students who were aged 10 years, completed physical fitness tests between grades 4 and 13, and had at least 1 year of follow-up. Data analysis was last performed on January 15, 2023.

Exposures

Physical fitness tests included cardiorespiratory endurance (CE; number of minutes to complete an 800-m run), musculoskeletal endurance (ME; number of bent-leg curl-ups in 1 minute), musculoskeletal power (MP; standing broad jump distance), and flexibility fitness (FF; 2-leg sit-and-reach distance).

Main Outcomes and Measures

Subsequent risk of IBD was compared among students based on physical fitness test results. Six-year cumulative incidences and hazard ratios (HRs) were calculated after adjusting for competing mortality. Performance was reported in quantiles, ranging from 1 (best) to 4 (poorest).

Results

There were 4 552 866 students who completed physical fitness tests between grades 4 and 13; among these students, 1 393 641 were aged 10 years and were included in the analysis. Six-year cumulative incidence of IBD risk was lowest among students in the best-performing quantile of CE (quantile 1, 0.74% [95% CI, 0.63%-0.86%]; P < .001), ME (0.77% [0.65%-0.90%]; P < .001), and MP (0.81% [0.68%-0.93%]; P = .005) compared with students in quantiles 2 through 4, respectively; however, no association was observed for quantiles of FF. After adjusting for competing HRs for mortality and other confounders, better CE was inversely associated with IBD risk (adjusted HR, 0.36 [95% CI, 0.17-0.75]; P = .007). Other measures of physical fitness were not independently associated with IBD risk.

Conclusions and Relevance

The results of this study suggest that CE was inversely associated with IBD risk among children and adolescents, but ME, MP, and FF were not independently associated with IBD risk. Future studies that explore the mechanisms are needed.

Cachexia, chorea, and pain in chronic nonbacterial osteitis and inflammatory bowel disease: a case report

BACKGROUND

Inflammatory bowel disease is an inflammatory disorder that primarily impacts the gastrointestinal tract, leading to malnutrition and chronic microscopic intestinal blood loss. Uncontrolled systemic inflammation can impact other parts of the body, known as extraintestinal manifestations. Up to 25% of patients with inflammatory bowel disease are reported to have these complications in their skin, joints, bones, eyes, liver, lung, and pancreas (Rogler et al. in Gastroenterology 161(4):1118-1132, 2021). Neurologic involvement as extraintestinal manifestations are less common, reported at 3-19%, including neuropathies, demyelination, and cerebrovascular events (Morís in World J Gastroenterol. 20(5):1228-1237, 2014).

CASE PRESENTATION

A 13-year-old Caucasian boy presented with 1 month of progressive lower-extremity pain, weakness, and weight loss. His physical examination was notable for cachexia, lower-extremity weakness, and chorea. Labs revealed normocytic anemia and systemic inflammation. Imaging revealed symmetric abnormal marrow signal in the pelvis and upper femurs. Pathologic examination of the bone revealed chronic inflammation consistent with chronic nonbacterial osteitis. Endoscopy revealed colonic inflammation consistent with inflammatory bowel disease.

CONCLUSIONS

Children and adolescents with musculoskeletal pain lasting more than 2 weeks with systemic signs or symptoms like weight loss should prompt evaluation for systemic inflammatory disorders such as chronic nonbacterial osteitis, which can occur in isolation or associated with inflammatory bowel disease. This patient also had a nonspecific neurologic abnormality, chorea, which resolved with treatment of underlying inflammatory disorder. These extraintestinal manifestations may be concurrent with or precede intestinal inflammation, requiring a high index of suspicion when investigating nonspecific systemic inflammation.

Gene expression profiling in white blood cells reveals new insights into the molecular mechanisms of thalidomide in children with inflammatory bowel disease

Thalidomide has emerged as an effective immunomodulator in the treatment of pediatric patients with inflammatory bowel disease (IBD) refractory to standard therapies. Cereblon (CRBN), a component of E3 protein ligase complex that mediates ubiquitination and proteasomal degradation of target proteins, has been identified as the primary target of thalidomide. CRBN plays a crucial role in thalidomide teratogenicity, however it is unclear whether it is also involved in the therapeutic effects in IBD patients. This study aimed at identifying the molecular mechanisms underpinning thalidomide action in pediatric IBD. In this study, ten IBD pediatric patients responsive to thalidomide were prospectively enrolled. RNA-sequencing (RNA-seq) analysis and functional enrichment analysis were carried out on peripheral blood mononuclear cells (PBMC) obtained before and after twelve weeks of treatment with thalidomide. RNA-seq analysis revealed 378 differentially expressed genes before and after treatment with thalidomide. The most deregulated pathways were cytosolic calcium ion concentration, cAMP-mediated signaling, eicosanoid signaling and inhibition of matrix metalloproteinases. Neuronal signaling mechanisms such as CREB signaling in neurons and axonal guidance signaling also emerged. Connectivity Map analysis revealed that thalidomide gene expression changes were similar to those exposed to MLN4924, an inhibitor of NEDD8 activating enzyme, suggesting that thalidomide exerts its immunomodulatory effects by acting on the ubiquitin-proteasome pathway. In vitro experiments on cell lines confirmed the effect of thalidomide on candidate altered pathways observed in patients. These results represent a unique resource for enhanced understanding of thalidomide mechanism in pediatric patients with IBD, providing novel potential targets associated with drug response.

Menstrual Dysfunction in Adolescents with Chronic Illness: A Systematic Review

STUDY OBJECTIVE

Menstrual dysfunction can impact both the physical and emotional health of young people¹. Multiple chronic disease have been associated with menstrual dysfunction in adults², however there is little research in adolescents, despite non adherence and sub-optimal illness control in this group. We aimed to identify the impact chronic illness has on the age of menarche (AAM) and the menstrual cycle in adolescents.

METHODS

Studies were extracted of female adolescents aged 10-19 who had a chronic physical illness. Data included outcomes on age of menarche and/or menstrual cycle quality. Exclusion criteria aimed to exclude diseases where menstrual dysfunction was a known part of the disease pathophysiology i.e. polycystic ovarian syndrome³, or in which medications were used that directly impacted gonadal function⁴. A literature search (to January 2022) was performed on EMBASE, PubMed and Cochrane library databases. Two widely used modified quality analysis tools were used.

RESULTS

Our initial search netted 1451 articles, of which 95 full texts were examined and 43 met inclusion criteria. 27 papers focussed on Type 1 Diabetes (T1D), with 8 papers examining adolescents with cystic fibrosis (CF) and the remaining studying inflammatory bowel disease (IBD), juvenile idiopathic arthritis (JIA), coeliac disease and chronic renal disease. Metanalysis of 933 patients with T1D versus 5244 controls demonstrated a significantly later AAM in T1D (by 0.42 years; p=<0.00001). There was also a significant association between higher HbA1c and insulin dose (IU/kg) and later age of menarche. Eighteen papers reviewed other aspects of menstruation, including dysmenorrhoea, oligomenorrhoea, amenorrhoea and ovulatory function, with variable findings.

CONCLUSION

The majority of studies were small and in single populations. Despite this, there was evidence of delayed menarche and some evidence of irregular menses in those with CF and T1D. Further structured studies are needed to evaluate menstrual dysfunction in adolescents and how it relates to their chronic illness.

Infliximab vs adalimumab: Points to consider when selecting anti-tumor necrosis factor agents in pediatric patients with Crohn’s disease

Biologic agents with various mechanisms against Crohn’s disease (CD) have been released and are widely used in clinical practice. However, two anti-tumor necrosis factor (TNF) agents, infliximab (IFX) and adalimumab (ADL), are the only biologic agents approved by the Food and Drug Administration for pediatric CD currently. Therefore, in pediatric CD, the choice of biologic agents should be made more carefully to achieve the therapeutic goal. There are currently no head-to-head trials of biologic agents in pediatric or adult CD. There is a lack of accumulated data for pediatric CD, which requires the extrapolation of adult data for the positioning of biologics in pediatric CD. From a pharmacokinetic point of view, IFX is more advantageous than ADL when the inflammatory burden is high, and ADL is expected to be advantageous over IFX in sustaining remission in the maintenance phase. Additionally, we reviewed the safety profile, immunogenicity, preference, and compliance between IFX and ADL and provide practical insights into the choice of anti-TNF therapy in pediatric CD. Careful evaluation of clinical indications and disease behavior is essential when prescribing anti-TNF agents. In addition, factors such as the efficacy of induction and maintenance of remission, safety profile, immunogenicity, patient preference, and compliance play an important role in evaluating and selecting treatment options.

Safety and Efficacy of Fecal Microbiota Transplantation in Treatment of Inflammatory Bowel Disease in the Pediatric Population: A Systematic Review and Meta-Analysis

Background and Aims: Fecal microbiota transplantation (FMT) has been increasingly studied in the inflammatory bowel disease (IBD) population. However, most studies have focused on the adult population, and the safety and efficacy of FMT in a pediatric population is less well understood. This systematic review and meta-analysis investigates the safety and efficacy of FMT in a pediatric IBD population. Methods: A comprehensive literature search of publications published prior to 30 June 2022 was undertaken. Safety data, IBD-related outcomes, and microbiome analysis were obtained from these studies when accessible. Individual estimates of each study were pooled, and sensitivity analysis was conducted. Results: Eleven studies satisfied our eligibility criteria. The calculated pooled rate of adverse events was 29% (95% confidence interval [CI]: 15.0%, 44.0%; p < 0.001; I2 = 89.0%, Q = 94.53), and the calculated pooled rate of serious adverse events was 10% (95% confidence interval [CI]: 6.0%, 14.0%; p = 0.28; I2 = 18.0%, Q = 9.79). One month after FMT, clinical response was achieved in 20/34 (58.8%) pediatric IBD patients, clinical remission was achieved in 22/34 (64.7%), and both clinical response and remission were achieved in 15/34 (44.1%) pediatric IBD patients. Conclusions: FMT can be a safe and effective treatment in the pediatric IBD population and may demonstrate improved safety and efficacy in the pediatric population compared to the adult population. However, our results are limited by a lack of established protocol as well as long-term follow-up for FMT in a pediatric IBD population.

Efficacy of short-chain polypeptide-based EEN formulas in alleviating intestinal injury in children with Crohn's disease: a single-center study in China

Short-chain polypeptides are composed of three to nine amino acids, which can be absorbed by the intestinal tract without digestive enzymes and ATP energy. Crohn's disease (CD) is a chronic non-specific disease derived from inflammation and damage of the gastrointestinal tract. In this study, we aim to investigate the effect of short-chain polypeptide-based exclusive enteral nutrition (EEN) formulas on intestinal injury in Chinese children with active CD. From January 2013 to January 2019, a total of 84 consecutive children with a diagnosis of Crohn's disease (CD) in the Department of Pediatric Gastroenterology, Children's Hospital of Nanjing Medical University, were divided into mild and moderate-to-severe active CD groups. Each group was further divided into two subgroups: drug group and short-chain polypeptide plus drug group. Tests were carried out on the levels of intestinal fatty acid binding protein (I-FABP) in the blood, fecal calprotectin (FC), and occludin protein in the intestinal mucosa 1 day before treatment and 8 weeks after treatment. Endoscopic and histopathological observations were detected to compare the changes in intestinal injury in children with active CD. After 8 weeks of treatment, the SES-CD scores and Chiu scores of the ileocecal area and terminal ileum of children with mild active CD and the ileocecal area of children with moderate-to-severe active CD in short-chain polypeptide plus drug group were significantly lower than those in the drug group. The OD value of occludin in the terminal ileum and ileocecal area of children with mild active CD and the ileocecal area of children with moderate-to-severe active CD after short-chain polypeptide-based EEN formulas and drug treatment was significantly higher than those in the drug group (p < 0.05). Meanwhile, the levels of FC and I-FABP were significantly decreased (p < 0.05). The results showed that short-chain polypeptide-based EEN formulas effectively alleviate intestinal injury in children with active CD.

The single-cell transcriptional landscape of innate and adaptive lymphocytes in pediatric-onset colitis

Innate lymphoid cells (ILCs) are considered innate counterparts of adaptive T cells; however, their common and unique transcriptional signatures in pediatric inflammatory bowel disease (pIBD) are largely unknown. Here, we report a dysregulated colonic ILC composition in pIBD colitis that correlates with inflammatory activity, including accumulation of naive-like CD45RA⁺CD62L^- ILCs. Weighted gene co-expression network analysis (WGCNA) reveals modules of genes that are shared or unique across innate and adaptive lymphocytes. Shared modules include genes associated with activation/tissue residency, naivety/quiescence, and antigen presentation. Lastly, nearest-neighbor-based analysis facilitates the identification of "most inflamed" and "least inflamed" lymphocytes in pIBD colon with unique transcriptional signatures. Our study reveals shared and unique transcriptional signatures of colonic ILCs and T cells in pIBD. We also provide insight into the transcriptional regulation of colonic inflammation, deepening our understanding of the potential mechanisms involved in pIBD.

Hungarian Linguistic, Cross-Cultural and Age Adaptation of Transition Specific Questionnaires in Patients with Inflammatory Bowel Disease

Objective: In the TRANS-IBD clinical trial, the outcomes are measured with selected validated questionnaires. Cross-cultural and age adaptations of the Self-Efficacy Scale for adolescents and young adults (IBD-SES), the Transition Readiness Assessment Questionnaire (TRAQ), and the Self-Management and Transition Readiness Questionnaire (STARx) were performed. Methods: Linguistic and cultural adaptation was carried out with the usage of reliability coefficients (Cronbach's α coefficients, Spearman's rank correlation), and with confirmatory factor analysis (CFA; root Mean Square Error of Approximation [RMSEA], Comparative Fit Index [CFI], and Tucker-Lewis Index [TLI]). Results: 112 adolescents participated in the study (45.5% male, mean age 17 ± 1.98 years). CFA was acceptable in the IBD-SES and the TRAQ. Internal consistency was acceptable in IBD-SES and good in TRAQ (0.729; 0.865, respectively). Test-retest reliability was good in IBD-SES, but below the acceptable threshold in TRAQ (ρ = 0.819; ρ = 0.034). In STARx tools, RMSEA showed poor fit values, CFI and TLI were below acceptable fit values, and internal consistency was not satisfied (0.415; 0.693, respectively), while test-retest reliabilities were acceptable (ρ = 0.787; ρ = 0.788, respectively). Conclusions: Cross-cultural, age-specific adaptation was successfully completed with IBD-SES and TRAQ. Those are comparable to the original validated versions. The adaption of the STARx tools was not successful.

[68Ga]Ga-FAPI-04 PET/CT on assessing Crohn's disease intestinal lesions

BACKGROUND

Fibrosis and inflammation are major pathological changes of Crohn's disease (CD). Early detection and accurate severity evaluation of CD are critical for patient's prognosis. Endoscopy is widely used to evaluate CD progression. Herein, we evaluated the efficacy of [⁶⁸Ga]Ga-FAPI-04 PET/CT to identify lesions and assess the progression of CD.

METHODS

All CD patients received computed tomography enterography (CTE), [⁶⁸Ga]Ga-FAPI-04 PET/CT examination, and ileocolonoscopy within 1 week. Two independent gastroenterologists computed the Crohn's disease activity index (CDAI) of all patients. Two radiology physicians assessed the CTE images separately, and the CTE scores were calculated. Lastly, two nuclear medicine physicians independently examined the [⁶⁸Ga]Ga-FAPI-04 PET/CT images. Once the FAPI uptake of the intestinal segment was equal or higher relative to the liver (considered FAPI-positive), the target-to-background ratio (TBR) and global FAPI PET/CT score were computed, representing the independent intestinal activity and activity of all intestinal segments, respectively. Levels of fecal calprotectin (FCP) and C-reactive protein (CRP) were determined before the endoscopy. The Crohn's disease endoscopy index of severity (CDEIS) and the simple endoscopic score for Crohn's disease (SES-CD) were calculated during the endoscopy. Finally, all data were obtained and analyzed.

RESULTS

There were 74 intestinal segments in 16 patients were assessed. [⁶⁸Ga]Ga-FAPI-04 PET/CT identified 42 of 45 endoscopically lesioned segments (endoscopic lesions detection sensitivity: 93.3%), while CTE identified 39 of them (endoscopic lesions detection sensitivity: 86.7%). According to the receiver operating characteristic (ROC) analysis, [⁶⁸Ga]Ga-FAPI-04 PET/CT showed better performance in the detection of endoscopic lesions compared with CTE (P < 0.05). The TBR was significantly associated with the CTE score (r = 0.81; (95% CI): 0.736-0.869; P < 0.0001) and SES-CD values (r = 0.86; (95% CI): 0.776-0.908; P < 0.0001). In addition, the global FAPI PET/CT score was significantly correlated with FCP (r = 0.52; 95% CI, 0.02-0.81; P = 0.039), CRP (r = 0.60; 95% CI, 0.13-0.85; P = 0.014), CDEIS (r = 0.55; 95% CI, 0.06-0.83; P = 0.028), and CDAI (r = 0.81; 95% CI, 0.50-0.93; P < 0.0001).

CONCLUSION

In summary, [⁶⁸Ga]Ga-FAPI-04 PET/CT correlated well with endoscopic, CTE, clinical, and biomarkers of CD. It was also highly sensitive in the detection of different classes of lesions in all intestinal segments, and unlike other examinations, this technique required no patient fasting or bowel preparation. Therefore, [⁶⁸Ga]Ga-FAPI-04 PET/CT may be a promising method for assessing the activity of CD.

Gram-scale preparation of quercetin supramolecular nanoribbons for intestinal inflammatory diseases by oral administration

Gastrointestinal (GI) tract, which possesses the largest surface area of mucosa in the body, is easily suffered from inflammatory damages under the exposure of external stimulations. Excessive reactive oxygen species (ROS) production and continuous oxidative stress in intestines can elicit local mucosal injury, accelerate mucosal ulceration, and amplify the inflammatory response. Thereby, antioxidant therapy is a potential strategy against intestinal inflammatory diseases. Herein, we demonstrate the gram-scale preparation of quercetin supramolecular nanoribbons (SNRs) by using free quercetin molecules as the sole building block for preventing and treating intestinal inflammatory diseases. Unlike current clinical medicines, which mainly confront with poor response and severe adverse effects via bloodstream delivery, our quercetin SNRs possess an excellent antioxidant activity in the harsh environments of GI tract, a relative long retention time in GI tract, an admirable metabolism in GI tract without burdening other organs, and a specific adhesion to the inflamed intestinal epithelium via electrostatic interactions. These advantages strongly guarantee the applications of quercetin SNRs as oral medicines for intestinal inflammatory diseases. After establishing the models of intestinal inflammatory diseases caused by irradiation and drug stimulations, our quercetin SNRs exhibit the promising protective and therapeutic effects for radiation-induced acute enteritis and dextran sulfate sodium (DSS)-induced acute colitis. Because the super easy and fast preparation procedure and the nearly 100% loading capacity of quercetin SNRs, the current work provides a supramolecular nanomedicine with great clinical translation potential against intestinal inflammatory diseases.

Identification of FCN1 as a novel macrophage infiltration-associated biomarker for diagnosis of pediatric inflammatory bowel diseases

BACKGROUND

The incidence of pediatric inflammatory bowel disease (PIBD) has been steadily increasing globally. Delayed diagnosis of PIBD increases the risk of complications and contributes to growth retardation. To improve long-term outcomes, there is a pressing need to identify novel markers for early diagnosis of PIBD.

METHODS

The candidate biomarkers for PIBD were identified from the GSE117993 dataset by two machine learning algorithms, namely LASSO and mSVM-RFE, and externally validated in the GSE126124 dataset and our PIBD cohort. The role of ficolin-1 (FCN1) in PIBD and its association with macrophage infiltration was investigated using the CIBERSORT method and enrichment analysis of the single-cell dataset GSE121380, and further validated using immunoblotting, qRT-PCR, and immunostaining in colon biopsies from PIBD patients, a juvenile murine DSS-induced colitis model, and THP-1-derived macrophages.

RESULTS

FCN1 showed great diagnostic performance for PIBD in an independent clinical cohort with the AUC of 0.986. FCN1 expression was upregulated in both colorectal biopsies and blood samples from PIBD patients. Functionally, FCN1 was associated with immune-related processes in the colonic mucosa of PIBD patients, and correlated with increased proinflammatory M1 macrophage infiltration. Furthermore, single-cell transcriptome analysis and immunostaining revealed that FCN1 was almost exclusively expressed in macrophages infiltrating the colonic mucosa of PIBD patients, and these FCN1⁺ macrophages were related to hyper-inflammation. Notably, proinflammatory M1 macrophages derived from THP-1 expressed high levels of FCN1 and IL-1β, and FCN1 overexpression in THP-1-derived macrophages strongly promoted LPS-induced activation of the proinflammatory cytokine IL-1β via the NLRP3-caspase-1 axis.

CONCLUSIONS

FCN1 is a novel and promising diagnostic biomarker for PIBD. FCN1⁺ macrophages enriched in the colonic mucosa of PIBD exhibit proinflammatory phenotypes, and FCN1 promotes IL-1β maturation in macrophages via the NLRP3-caspase-1 axis.

Vaccination coverage in children with juvenile idiopathic arthritis, inflammatory bowel diseases, and healthy peers: Cross-sectional electronic survey data

BACKGROUND

Patients with immune-mediated diseases, such as juvenile idiopathic arthritis (JIA) and inflammatory bowel disease (IBD) are at increased risk of developing infections, due to disease-related immune dysfunction and applying of immunosuppressive drugs.

AIM

To evaluate vaccine coverage in patients with IBD and JIA, and compare it with healthy children.

METHODS

In the cross-sectional study we included the data from a questionnaire survey of 190 Legal representatives of children with JIA (n = 81), IBD (n = 51), and healthy children (HC, n = 58). An electronic online questionnaire was created for the survey.

RESULTS

There were female predominance in JIA patients and younger onset age. Parents of JIA had higher education levels. Employment level and family status were similar in the three studied groups. Patients with JIA and IBD had lower vaccine coverage, without parental rejection of vaccinations in IBD, compare to JIA and healthy controls. The main reason for incomplete vaccination was medical conditions in IBD and JIA. IBD patients had a lower rate of normal vaccine-associated reactions compared to JIA and HC. The encouraging role of physicians for vaccinations was the lowest in JIA patients. IBD patients had more possibilities to check antibodies before immune-suppressive therapy and had more supplementary vaccinations compared to JIA and HC.

CONCLUSION

JIA and IBD patients had lower vaccine coverage compared to HC. Physicians' encouragement of vaccination and the impossibility of discus about future vaccinations and their outcomes seemed the main factors for patients with immune-mediated diseases, influencing vaccine coverage. Further investigations are required to understand the reasons for incomplete vaccinations and improve vaccine coverage in both groups, especially in rheumatic disease patients. The approaches that stimulate vaccination in healthy children are not always optimal in children with immune-mediated diseases. It is necessary to provide personalized vaccine-encouraging strategies for parents of chronically ill children with the following validation of these technics.

The use of calgranulin-C (S100A12) and fecal zonulin as possible non-invasive markers in children with inflammatory bowel disease: a clinical study

Calgranulin-C (S100A12) and zonulin are considered markers of intestinal inflammation. Our aim was to evaluate fecal S100A12 (f-S100A12) and fecal zonulin (f-zonulin) in children with inflammatory bowel disease (IBD), compared to fecal calprotectin (FC) and serum inflammatory markers. We enrolled children with a previous diagnosis of Crohn's disease (CD) and ulcerative colitis (UC). F-S100A12, f-zonulin, and FC were determined by enzyme-linked immunosorbent assay (ELISA). Endoscopic examination was considered in the patients who underwent ileocolonoscopy within 2 weeks from the enrollment. One hundred seventeen children, 39.3% with CD and 60.7% with UC were enrolled. In both CD and UC, there was a significant direct correlation between FC and f-S100A12 levels. In children with CD and UC, both FC and f-S100A12 correlated with markers of serum inflammation. We found difference in FC and f-S100A12 levels between patients in clinical relapse and remission (FC: mean 1027 ± 818 mcg/ml vs 580 ± 695 mcg/ml respectively, p = 0.028; f-S100A12: mean 66.4 ± 48.2 mcg/ml vs 42.7 ± 40 mcg/ml, respectively p = 0.02). Moreover, we found difference in FC between children with endoscopic inflammation and remission (mean 825 ± 779 mcg/ml vs 473.3 ± 492 mcg/ml, respectively p = 0.048), as well as for f-S100A12 (53 ± 43 mcg/ml vs mean 31 ± 33 mcg/ml vs, respectively p = 0.019). No significant results were found for f-zonulin.

CONCLUSION

Our data suggest that f-S100A12 and FC are both useful non-invasive biomarkers in the management of pediatric IBD in follow up and in monitoring endoscopic and clinical relapse.

WHAT IS KNOWN

• Fecal calprotectin (FC), fecal S100A12 (f- S100A12), and fecal zonulin represent potential noninvasive markers of gut inflammation. • Since S100A12 is predominantly expressed by granulocytes, high levels of f-S100A12 should be more specific for inflammation than FC.

WHAT IS NEW

• FC and f-S100A12 were correlated to each other and despite the lack of correlation with disease location, they were associated with endoscopic inflammation and clinical relapse in children with IBD. • No significant correlations were found between f-zonulin and the inflammatory parameters.

Basiliximab therapy for immune-mediated bowel disease in a pediatric heart transplant patient

In pediatric patients who undergo heart transplantation, severe immune-mediated bowel disease has been reported. Management is complex, and there are little data discussing the use of basiliximab for immune-mediated bowel disease. This case report discusses a pediatric patient who developed immune-mediated bowel disease following heart transplantation and was successfully managed with basiliximab.

A clinical approach to tubulopathies in children and young adults

Kidney tubules are responsible for the preservation of fluid, electrolyte and acid-base homeostasis via passive and active mechanisms. These physiological processes can be disrupted by inherited or acquired aetiologies. The net result is a tubulopathy. It is important to make a prompt and accurate diagnosis of tubulopathies in children and young adults. This allows timely and appropriate management, including disease-specific therapies, and avoids complications such as growth failure. Tubulopathies can present with a variety of non-specific clinical features which can be diagnostically challenging. In this review, we build from this common anatomical and physiological understanding to present a tangible appreciation of tubulopathies as they are likely to be clinically encountered among affected children and young adults.

TIPE-2 ameliorates inflammatory bowel disease in mice via inhibiting STAT3 and NF-kB activation

TIPE-2 has been identified as a negative regulator of both innate and adaptive immunity and is involved in several inflammatory diseases. However, the immune inhibition mechanism of TIPE-2 involved in inflammatory bowel disease has not been well studied. Therefore, the aim of this study was to investigate whether TIPE-2 improved experimental colitis by reducing high levels of inflammation in the intestine. Lentivirus encoding TIPE-2 was administered to mice by intrarectal injection after colitis induction. Histological analysis was used to analyze sections of the intestine. Protein expression induced by STAT3 and NF-κB signaling was analyzed by western blot. We found that TIPE-2 reduced the colitis activity index score and the histological score of the intestine. TIPE-2 also decreased inflammatory cytokine levels in the intestine. Additionally, TIPE-2 inhibited STAT3 and NF-kB activation. These results suggested that TIPE-2 might attenuate inflammation of colitis via inhibiting of STAT3 and NF-kB activation.

Blood regulatory T cells in inflammatory bowel disease, a systematic review, and meta-analysis

INTRODUCTION

Inflammatory bowel disease (IBD) is an autoimmune disease involving various parts of the gastrointestinal (GI) tract, which includes Crohn's disease (CD) and ulcerative colitis (UC). Due to the contradictory results regarding the percentage of peripheral blood (PB) regulatory T cells (Tregs) in IBD patients, this meta-analysis aimed to determine the Tregs frequency in IBD patients.

METHOD

We searched PubMed, Web of Science, SCOPUS, and Google Scholar databases for relevant observational articles that analyzed and reported the frequency of PB Tregs in IBD patients and healthy control groups. After choosing the related articles by two reviewers, the data regarding the definition of Tregs and their frequencies in different groups were recorded.

RESULT

In 22 studies, the results showed a nonsignificant difference in the frequency of PB Tregs between IBD cases and control subjects (SMD: -0.27, 95 % CI: -0.78, 0.23). However, the frequency of CD4⁺CD25⁺CD127^- (SMD: -0.89, 95 % CI: -1.52, -0.26) and CD4⁺CD25⁺FoxP3⁺ (SMD: -1.32, 95 % CI: -2.37, -0.26) Tregs were significantly lower in IBD cases, compared to healthy subjects. Also, UC cases and active IBD cases showed a significantly lower frequency of Treg cells, compared to controls and remission IBD cases, respectively (SMD: -0.68, 95 % CI: -1.24, -0.11 and SMD: -0.60, 95 % CI: -0.93, -0.27).

CONCLUSION

Our study highlighted a probable decrease of Tregs in IBD patients, especially the patients with active states of the disease. The decrease of Treg cells might cause an imbalance in the immune system and the over-activation of auto-immune responses against the digestive tract.

Inflammatory Bowel Disease and Rosacea: A Two-Sample Mendelian Randomization Study

Background. Inflammatory bowel disease (IBD) might increase the risk of rosacea; however, the relationship between IBD and rosacea is not determined. In this study, Mendelian randomization (MR) design was used to explore the potential causal association between IBD and rosacea. Methods. A two-sample MR was explored from large-scale genetic summary data from genome-wide association study (GWAS), including IBD (n = 59959) and its main subtype Crohn’s disease (CD) (n = 40266) and ulcerative colitis (UC) (n = 45975). Summarized data of rosacea (n = 1877) were obtained from different GWAS studies. Based on previous observational studies, our main analyses were conducted by the inverse-variance weighted (IVW) method with the random-effects model, with a complementary with the other two analyses: weighted median method and MR-Egger approach. Results. The results of IVW methods demonstrated that genetically predicted IBD was significantly associated with rosacea (odds ratio (OR), 1.18 (95% CI, 1.05–1.32), $P=0.004$ ). The weighted median method and MR-Egger regression also demonstrated directionally similar results (all $P<0.05$ ). In addition, both funnel plots and MR-Egger intercepts indicated no directional pleiotropic effects between IBD and rosacea. CD was strongly associated with it in its subtype analysis (odds ratio (OR), 1.11 (95% CI, 1.01–1.22), $P=0.04$ ), and UC was also causally associated with rosacea, but its statistical significance did not appear to be significant (odds ratio (OR), 1.16 (95% CI, 0.99–1.36), $P=0.07$ ). Conclusions. Our study provided potential evidence between genetically predicted IBD and rosacea, and the degree of association of different subtypes of IBD for rosacea is different. In addition, we found that the mechanism of IBD affecting the pathogenesis of rosacea is closely related to the variation of IL23R. Blocking the IL-23 signaling pathway might be a reasonable strategy to treat IBD and prevent rosacea. Understanding the specific relationship between IBD and rosacea provides the possibility to treat both clinically and guide the development of new drugs.

Association between Inflammatory Bowel Disease and Iridocyclitis: A Mendelian Randomization Study

BACKGROUND

Iridocyclitis (IC) is a common extraintestinal manifestation of inflammatory bowel disease (IBD). Observational studies showed patients with ulcerative colitis (UC) and Crohn's disease (CD) both have a higher risk of IC. However, due to the inherent limitations of observational studies, the association and its directionality between the two forms of IBD and IC remain undiscerned.

METHODS

Genetic variants for IBD and IC were selected as instruments from genome-wide association studies (GWAS) and FinnGen database as instrumental variables, respectively. A bidirectional Mendelian randomization (MR) and multivariable MR were performed successively. Three different MR methods were performed to determine the causal association, including inverse-variance weighted (IVW), MR Egger, and weighted median, whereas IVW was used as the main analysis. Different methods for sensitivity analysis were used, including MR-Egger intercept test, MR Pleiotropy RESidual Sum and Outlier test, Cochran's Q test, and leave-one-out analysis.

RESULTS

Bidirectional MR suggested both UC and CD were positively associated with IC as a whole, acute and subacute IC, and chronic IC. However, in the MVMR analysis, only the association from CD to IC remained stable. In the reverse analysis, no association was observed from IC to UC or CD.

CONCLUSIONS

Both UC and CD are associated with an increased risk of IC compared with healthy individuals. However, the association between CD and IC is stronger. In the reverse direction, patients with IC do not suffer a higher risk of UC or CD. We emphasize the importance of ophthalmic examinations for IBD patients, especially for CD patients.

Exploring treatment of inflammatory bowel disease with infliximab in the Middle East and Northern Africa: An analysis of the HARIR observational cohort study

BACKGROUND

In 2017, inflammatory bowel disease, including Crohn's disease (CD) and ulcerative colitis (UC) affected more than 6.8 million people worldwide, with increased incidence in newly industrialized countries. Although treatment options were previously limited to symptom reduction, current approaches benefit from disease-modifying biologics. In this study, we aimed to explore disease characteristics, treatment, and outcomes of patients with CD or UC treated with infliximab or golimumab in routine clinical practice in the Middle East and Northern Africa.

METHODS

HARIR was a prospective, observational, multicenter study (NCT03006198), in patients who were treatment naïve or who received two or fewer biologic agents. Observed data from routine clinical practice were presented descriptively.

RESULTS

Data from 86 patients enrolled from five countries (Algeria, Egypt, Kuwait, Qatar, and Saudi Arabia) were analyzed, 62 with CD and 24 with UC. All patients received infliximab. Clinically meaningful efficacy data were observed only for the CD group (up to Month 3) due to limited patient numbers. Crohn's Disease Activity Index (CDAI) scores at Month 3 indicated a positive response to treatment (reduced score of ≥70 and ≥25% compared with baseline) for 14/48 (29.2%) patients; notably, 28/52 (53.8%) patients had CDAI score <150 at baseline. Rates of serious and severe adverse events (AEs) were low in both groups. The most common AEs were gastrointestinal disorders.

CONCLUSION

Infliximab treatment was well tolerated in this Middle Eastern and Northern African population, and a clinical response was observed for 29.2% of CD patients. Limited accessibility to biologics and concomitant treatments restricted study conduct.

Current perspectives on pediatric inflammatory bowel disease focusing on transitional care management. What should we consider?

The prevalence of inflammatory bowel disease (IBD) continues to rise around the globe. Although the percentage of pediatric IBD patients seems to be increasing, rates are surprisingly heterogeneous among different populations. Although the pathogenesis of IBD is believed to be multifactorial, a genetic predisposition may be especially relevant in pediatric-onset IBD. Phenotypic characteristics can also be significantly different when comparing pediatric and adult-onset IBD. Patients that develop the disease at a younger age usually present with more extensive and more aggressive disease and develop complications faster when compared to those that develop it during adulthood. Children with IBD are found to have frequent mood disorders and have a higher risk of developing socio-economic hardship, failing to meet development milestones. Therefore, IBD management should always involve a multidisciplinary team that is not limited to medical providers. Most institutions do not have an established transition protocol and lack the resources and training for transition care. Although there is no consensus on an optimal timing to transition the patient's care to an adult team, it is usually accepted they should be eligible for adult care when most of the key transition points have been met. Management strategies should be tailored to each patient's developmental level and environment. A successful transition can improve the long-term outcomes such as sustained remission, medication adherence, mental health and social and academic performance, while decreasing healthcare utilization. Every institution that manages pediatric IBD patients should have a well-established transition protocol in order to make sure to maintain continuity of care.

Diagnostic delay in adult inflammatory bowel disease: A systematic review

BACKGROUND

The extent of diagnostic delay in inflammatory bowel disease (IBD) is incompletely understood. We aimed to understand the extent of diagnostic delay of IBD in adults and identify associations between patient or healthcare characteristics and length of delay.

METHODS

Articles were sourced from EMBASE, Medline and CINAHL from inception to April 2021. Inclusion criteria were adult cohorts (18 ≥ years old) reporting median time periods between onset of symptoms for Crohn's disease (CD), ulcerative colitis (UC) or IBD (i.e. CD and UC together) and a final diagnosis (diagnostic delay). Narrative synthesis was used to examine the extent of diagnostic delay and characteristics associated with delay. Sensitivity analysis was applied by the removal of outliers.

RESULTS

Thirty-one articles reporting median diagnostic delay for IBD, CD or UC were included. After sensitivity analysis, the majority of IBD studies (7 of 8) reported a median delay of between 2 and 5.3 months. From the studies examining median delay in UC, three-quarters (12 of 16) reported a delay between 2 and 6 months. In contrast, three-quarters of the CD studies (17 of 23) reported a delay of between 2 and 12 months. No characteristic had been examined enough to understand their role in diagnostic delay in these populations.

CONCLUSIONS

This systematic review provides robust insight into the extent of diagnostic delay in IBD and suggests further intervention is needed to reduce delay in CD particularly. Furthermore, our findings provide a benchmark value range for diagnostic delay, which such future work can be measured against.

Adalimumab Therapy in Pediatric Crohn Disease: A 2-Year Follow-Up Comparing "Top-Down" and "Step-Up" Strategies

OBJECTIVES

European Crohn's Colitis Organization (ECCO) and the European Society of Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidelines recommend the early use of anti-tumor necrosis factor (TNF) biologicals in pediatric Crohn disease (CD) patients with positive predictors for poor outcome. The objective of the present study was to compare early "Top-Down" use of adalimumab (ADA) immunomodulator/biologics-naive patients to conventional "Step-Up" management.

METHODS

One hundred and twenty consecutive patients with a confirmed diagnosis of CD and treated with ADA between 2008 and 2019 were included and allocated to the ADA-Top Down (n = 59) or ADA-Step Up group (n = 61). The primary endpoint was prolonged steroid-/enteral nutrition-free clinical remission at 24 months, defined by a weighted Pediatric Crohn's Disease Activity Index (wPCDAI) < 12.5. Clinical and biological data were collected at 12 and 24 months.

RESULTS

At start of ADA, disease activity was comparable between the ADA-Top Down group and the ADA-Step Up group (wPCDAI = 31 ± 16 vs 31.3 ± 15.2, respectively, P = 0.84). At 24 months, the remission rate was significantly higher in the ADA-Top Down group (73% vs 51%, P < 0.01). After propensity score, the Top-Down strategy is still more effective than the Step-Up strategy in maintaining remission at 24 months [hazard ratio (HR) = 0.36, 95% CI (0.15-0.87), P = 0.02]. Patients in the ADA-Top Down group were mainly on monotherapy compared to patients in the ADA-Step Up group (53/55 vs 28/55 respectively, P < 0.001). Serum levels of ADA were higher in the ADA-Top Down group than in the ADA-Step Up group (12.8 ± 4.3 vs 10.4 ± 3.9 µg/mL, respectively, P < 0.01). There were no serious adverse events.

CONCLUSIONS

Early use of ADA appears to be more effective in maintaining relapse-free remission at 2 years, while using it as monotherapy. These findings further favor the recommendation of early anti-TNF use in high-risk CD patients.

Personalised azithromycin+metronidazole (PAZAZ), in combination with standard induction therapy, to achieve a faecal microbiome community structure and metagenome changes associated with sustained remission in paediatric Crohn's disease (CD): protocol of a pilot study

INTRODUCTION

Early relapse in Crohn's disease (CD) is associated with a more severe disease course. The microbiome plays a crucial role, yet strategies targeting the microbiome are underrepresented in current guidelines. We hypothesise that early manipulation of the microbiome will improve clinical response to standard-of-care (SOC) induction therapy in patients with a relapse-associated microbiome profile. We describe the protocol of a pilot study assessing feasibility of treatment allocation based on baseline faecal microbiome profiles.

METHODS AND ANALYSIS

This is a 52-week, multicentre, randomised, controlled, open-label, add-on pilot study to test the feasibility of a larger multicontinent trial evaluating the efficacy of adjuvant antibiotic therapy in 20 paediatric patients with mild-to-moderate-CD (10<PCDAI≤37.5; PCDAI, Pediatric Crohn's Disease Activity Index). SOC induction treatment will be Crohn's Disease Exclusion Diet+Partial Enteral Nutrition (CDED+PEN). Relapse-associated microbiome signatures will be evaluated using 16S rRNA gene sequencing and a previously generated Bayesian predictive model (BioMiCo) based on baseline stool. At week 4, patients in remission with relapse-associated signatures (group A) will be randomised to CDED+antibiotics (A2) or CDED+PEN alone (A1). Patients in remission without this signature will continue CDED+PEN alone (B). Patients not in remission will receive CDED+antibiotics regardless of their microbiome signature (C). Subjects in group A2 or C will receive a combination of azithromycin 7.5 mg/kg (weeks 4-8: 5 days/week; weeks 9-12: 3 days/week) with metronidazole 20 mg/kg/day (weeks 4-12). Primary outcomes will assess feasibility of treatment allocation and possible efficacy to sustain remission (PCDAI≤10, no need for reinduction). Exploratory outcomes will include changes in PCDAI, inflammatory markers and patient-reported outcomes. We will additionally explore changes in faecal microbiome taxonomic composition between groups.

ETHICS AND DISSEMINATION

This study was approved by METC-AMC and CCMO (Netherlands) and IWK Health Centre (Canada). The first version of this protocol was approved by North Carolina Children's Hospital (USA), Wolfson Medical Centre (Israel). The FDA (USA), Health Canada and Ministry of Health (Israel) have reviewed and approved the protocol. Results will be published in international peer-reviewed journals and summaries will be provided to the funders and participants.

TRIAL REGISTRATION NUMBER

NCT04186247.

Hirschsprung-associated inflammatory bowel disease: A multicenter study from the APSA Hirschsprung disease interest group

BACKGROUND/PURPOSE

A small number of Hirschsprung disease (HD) patients develop inflammatory bowel disease (IBD)-like symptoms after pullthrough surgery. The etiology and pathophysiology of Hirschsprung-associated IBD (HD-IBD) remains unknown. This study aims to further characterize HD-IBD, to identify potential risk factors and to evaluate response to treatment in a large group of patients.

METHODS

Retrospective study of patients diagnosed with IBD after pullthrough surgery between 2000 and 2021 at 17 institutions. Data regarding clinical presentation and course of HD and IBD were reviewed. Effectiveness of medical therapy for IBD was recorded using a Likert scale.

RESULTS

There were 55 patients (78% male). 50% (n = 28) had long segment disease. Hirschsprung-associated enterocolitis (HAEC) was reported in 68% (n = 36). Ten patients (18%) had Trisomy 21. IBD was diagnosed after age 5 in 63% (n = 34). IBD presentation consisted of colonic or small bowel inflammation resembling IBD in 69% (n = 38), unexplained or persistent fistula in 18% (n = 10) and unexplained HAEC >5 years old or unresponsive to standard treatment in 13% (n = 7). Biological agents were the most effective (80%) medications. A third of patients required a surgical procedure for IBD.

CONCLUSION

More than half of the patients were diagnosed with HD-IBD after 5 years old. Long segment disease, HAEC after pull through operation and trisomy 21 may represent risk factors for this condition. Investigation for possible IBD should be considered in children with unexplained fistulae, HAEC beyond the age of 5 or unresponsive to standard therapy, and symptoms suggestive of IBD. Biological agents were the most effective medical treatment.

LEVEL OF EVIDENCE

Level 4.

Identifying metabolic shifts in Crohn's disease using' omics-driven contextualized computational metabolic network models

Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract. A clear gap in our existing CD diagnostics and current disease management approaches is the lack of highly specific biomarkers that can be used to streamline or personalize disease management. Comprehensive profiling of metabolites holds promise; however, these high-dimensional profiles need to be reduced to have relevance in the context of CD. Machine learning approaches are optimally suited to bridge this gap in knowledge by contextualizing the metabolic alterations in CD using genome-scale metabolic network reconstructions. Our work presents a framework for studying altered metabolic reactions between patients with CD and controls using publicly available transcriptomic data and existing gene-driven metabolic network reconstructions. Additionally, we apply the same methods to patient-derived ileal enteroids to explore the utility of using this experimental in vitro platform for studying CD. Furthermore, we have piloted an untargeted metabolomics approach as a proof-of-concept validation strategy in human ileal mucosal tissue. These findings suggest that in silico metabolic modeling can potentially identify pathways of clinical relevance in CD, paving the way for the future discovery of novel diagnostic biomarkers and therapeutic targets.

Causal association between celiac disease and inflammatory bowel disease: A two-sample bidirectional Mendelian randomization study

Background

An epidemiological link between celiac disease (CeD) and inflammatory bowel disease (IBD) has been well established recently. In this study, Mendelian randomization (MR) analysis was performed employing pooled data of publicly available genome-wide association studies (GWAS) to determine the causal relationship between CeD and IBD, encompassing ulcerative colitis (UC) and Crohn's disease (CD).

Methods

Dataset of CeD was acquired from GWAS for 12,041 cases and 12,228 controls. A GWAS of more than 86,000 patients and controls was used to identify genetic variations underlying IBD. MR analyses were performed with an inverse-variance-weighted approach, an MR-Egger regression, a weighted-mode approach, a weighted-median method, and sensitivity analyses of MR pleiotropy residual sum and outlie (MR-PRESSO).

Results

MR demonstrated that genetic predisposition to CeD was linked to a augmented risk of IBD (OR: 1.1408; 95% CI: 1.0614-1.2261; P = 0.0003). In the analysis of the two IBD subtypes, genetic predisposition to CeD was also linked to increased risks of UC (OR: 1.1646; 95% CI: 1.0614-1.2779; P = 0.0012) and CD (OR: 1.1865; 95% CI: 1.0948-1.2859; P = 3.07E-05). Reverse MR analysis results revealed that genetic susceptibility to IBD and CD was correlated with an augmented risk of CeD. However, there was no genetic correlation between UC and CeD. All of the above results were validated with other GWAS databases.

Conclusion

There is a bidirectional causal relationship of CeD with IBD and CD. However, UC only augments the risk of developing CeD.

Treatment and biologic maintenance-dosing patterns among pediatric patients with ulcerative colitis or Crohn's disease

OBJECTIVES

To assess treatment patterns and initial and maintenance dosing of biologics over 3 years in pediatric patients with ulcerative colitis (UC) or Crohn's disease (CD), utilizing data from the ImproveCareNow registry.

METHODS

Pediatric patients diagnosed with UC or CD and aged 2-17 years were included in the study. Descriptive statistics were employed to summarize baseline demographics. The proportion of patients on medication for UC or CD were analyzed at the baseline visit, 1-year, and 3-year time points (Cohort 1). Biologic maintenance dosage was calculated only for patients who had data for dose and weight at all-time points (Cohort 2).

RESULTS

In Cohort 1 (UC = 1784; CD = 4720), baseline treatment in UC included corticosteroid, 5-ASA, and 6-MP/AZA; at 1-year and 3-year time points, treatment with 5-ASA and corticosteroid decreased, whereas 6-MP/AZA and anti-TNFs increased. In CD, baseline treatment included corticosteroid, anti-TNF, 6-MP/AZA, and methotrexate; use of corticosteroids decreased, whereas the use of methotrexate and anti-TNFs increased over 3 years. In Cohort 2 (UC = 350; CD = 1537), at first maintenance dose, UC patients on infliximab received a mean dose of 10.5 mg/kg/8 wk, adalimumab (weight < 40 kg and ≥40 kg) 1.3 mg/kg/2 wk and 0.8 mg/kg/2 wk, and vedolizumab 6.9 mg/kg/8 wks. At the first maintenance dose, CD patients on infliximab received a mean dose of 8.1 mg/kg/8 wk, adalimumab (weight < 40 kg) 1.1 mg/kg/2 wk, adalimumab (weight ≥ 40 kg) 0.8 mg/kg/2 wk, and vedolizumab 10.5 mg/kg/8 wks.

CONCLUSION

The use of corticosteroids was common at the initial visit in patients. Anti-TNFs remain the most used class of biologics, however, reported doses in our study were substantially higher than the standard dosing guidelines.

Anasarca as a manifestation of childhood volvulus: Diagnostic and management challenges in an 11-year old Nigerian boy

Background

Small intestine volvulus occurs more commonly among younger children. It often poses diagnostic challenges when it occurs in older children and adults. For good clinical outcomes, it is essential to have prompt presentation, diagnosis and early intervention. Anasarca is not a common clinical manifestation of small intestine volvulus.

Case Presentation

We report this unusual presentation of small intestine volvulus in an 11-year old Nigerian boy who first presented only with anasarca. While being investigated for the cause of the anasarca, he developed features of acute abdomen thought to be spontaneous bacteria peritonitis initially. He had surgery where the diagnosis of small intestine volvulus was made.

Conclusion

The diagnosis and management of both anasarca and small intestine volvulus could be fraught with challenges. It is possible that anasarca can be the first manifestation of small intestine volvulus.

Effects of psychosocial function in pediatric-onset inflammatory bowel disease during the coronavirus disease 2019 pandemic

BACKGROUND AND AIMS

Research on the effect of the coronavirus disease 2019 (COVID-19) pandemic on psychosocial function in patients with pediatric-onset inflammatory bowel disease (PIBD) is limited. This study aimed to evaluate the psychological status of patients with PIBD before and during the pandemic, and the relationship between mental health and disease activity.

METHODS

This study was a retrospective cohort study. Statistical analyses were performed to assess the relationship between demographic, clinical data and psychological data (questionnaires) of PIBD patients before and during the epidemic. The anxiety and depression emotional status of the guardians during the pandemic were evaluated.

RESULTS

In the PIBD follow-up cohort, 42 patients(male 61.9%) were included. Female with PIBD had lower pediatric quality of life inventory(PedsQL) scores (P = 0.007) and higher spence children's anxiety scale(SCAS) scores (P = 0.038) than male. The pandemic did not have a substantial impact on PedsQL, pittsburgh sleep quality index(PSQI), SCAS, or children's depression inventory(CDI) in patients with PIBD. The self-rating anxiety scale(SAS) score, anxiety rate, self-rating depression scale(SDS) score, and depression rate of PIBD guardians were significantly higher than those of healthy controls (SAS, P = 0.008; SDS, P = 0.001).

CONCLUSIONS

Female children with PIBD were more vulnerable to decreased QOL and increased anxiety than male children. The anxiety and depression status of PIBD guardians were significantly higher than those of healthy controls during the COVID-19 pandemic. But the COVID-19 pandemic did not significantly affect quality of life(QOL), sleep, anxiety, or depressive mood of patients with PIBD in our study.

Quality of Life Among Children with Inflammatory Bowel Disease in Saudi Arabia: A Cross-Sectional Study

Purpose

The aim of this study was to investigate the quality of life in children and adolescents aged 7-18 years with inflammatory bowel disease and identify the factors that influence it.

Patients and Methods

A multi-center cross-sectional study in which participants were recruited from 3 governmental hospitals in the Eastern Province of Saudi Arabia. A total of 61 children with inflammatory bowel disease were approached, 44 participants were included according to their age (7-18 years), disease duration of at least 6 months, and without any other co-morbidities. A translated Arabic version of the IMPACT-III questionnaire was used to assess the quality of life of the participants with inflammatory bowel disease. In addition, disease-specific indices were used to measure their disease activity; Harvey Bradshaw for patients with Crohn's disease and Pediatric Ulcerative Colitis Activity Index for ulcerative colitis patients.

Results

The mean age of the 44 participants was 13.36 ± 2.85. Crohn's disease accounted for 56.8% of the sample, while 36.4% had ulcerative colitis and 6.8% had unclassified type. The majority were males and in disease remission. The mean total score of the questionnaire was 74.10 ± 12.21, where the domain of social functioning scored the highest and the domain of emotional functioning scored the lowest. Children who are 11 years or older scored significantly higher in emotional functioning and total mean scores. Statistical significance was also observed between the well-being domain and not having flare-ups in the past year, as well as disease severity with emotional functioning, body image, and total mean scores. It was found that corticosteroid utilization is a predictor of poorer quality of life and was statistically significant with the body image domain.

Conclusion

Measuring the quality of life in children with inflammatory bowel disease can aid in reducing its burden and help address its factors.

Advances in Imaging of Inflammation, Fibrosis, and Cancer in the Gastrointestinal Tract

Gastrointestinal disease is prevalent and broad, manifesting itself in a variety of ways, including inflammation, fibrosis, infection, and cancer. However, historically, diagnostic technologies have exhibited limitations, especially with regard to diagnostic uncertainty. Despite development of newly emerging technologies such as optoacoustic imaging, many recent advancements have focused on improving upon pre-existing modalities such as ultrasound, computed tomography, magnetic resonance imaging, and endoscopy. These advancements include utilization of machine learning models, biomarkers, new technological applications such as diffusion weighted imaging, and new techniques such as transrectal ultrasound. This review discusses assessment of disease processes using imaging strategies for the detection and monitoring of inflammation, fibrosis, and cancer in the context of gastrointestinal disease. Specifically, we include ulcerative colitis, Crohn's disease, diverticulitis, celiac disease, graft vs. host disease, intestinal fibrosis, colorectal stricture, gastric cancer, and colorectal cancer. We address some of the most recent and promising advancements for improvement of gastrointestinal imaging, including unique discussions of such advancements with regard to imaging of fibrosis and differentiation between similar disease processes.

Management and monitoring of pediatric inflammatory bowel disease in the Asia-Pacific region: A position paper by the Asian Pan-Pacific Society for Pediatric Gastroenterology, Hepatology, and Nutrition (APPSPGHAN) PIBD Working Group: Surgical management, disease monitoring, and special considerations

Disease phenotype of pediatric inflammatory bowel disease (PIBD) in children from the Asia-Pacific region differs from that of children from the West. Many parts of Asia are endemic for tuberculosis, making diagnosis and management of pediatric Crohn's disease a challenge. Current available guidelines, mainly from Europe and North America, may not be completely applicable to clinicians caring for children with PIBD in Asia due to differences in disease characteristics and regional resource constraints. This position paper is an initiative from the Asian Pan-Pacific Society for Pediatric Gastroenterology, Hepatology and Nutrition (APPSPGHAN) that aims to provide an up-to-date, evidence-based approach to PIBD in the Asia-Pacific region. A group of pediatric gastroenterologists with a special interest in PIBD performed an extensive literature search covering epidemiology, disease characteristics and natural history, management, and monitoring. Attention was paid to publications from the region with special consideration to a resource-limited setting. This current position paper deals with surgical management, disease monitoring, immunization, bone health, and nutritional issues of PIBD in Asia. A special section on differentiating pediatric Crohn's disease from tuberculosis in children is included. This position paper provides a useful guide to clinicians in the surgical management, disease monitoring, and various health issues in children with IBD in Asia-Pacific region.

β-Myrcene Mitigates Colon Inflammation by Inhibiting MAP Kinase and NF-κB Signaling Pathways

Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders that include Crohn's disease (CD) and ulcerative colitis (UC). The incidence of IBD is rising globally. However, the etiology of IBD is complex and governed by multiple factors. The current clinical treatment for IBD mainly includes steroids, biological agents and need-based surgery, based on the severity of the disease. Current drug therapy is often associated with adverse effects, which limits its use. Therefore, it necessitates the search for new drug candidates. In this pursuit, phytochemicals take the lead in the search for drug candidates to benefit from IBD treatment. β-myrcene is a natural phytochemical compound present in various plant species which possesses potent anti-inflammatory activity. Here we investigated the role of β-myrcene on colon inflammation to explore its molecular targets. We used 2% DSS colitis and TNF-α challenged HT-29 adenocarcinoma cells as in vivo and in vitro models. Our result indicated that the administration of β-myrcene in dextran sodium sulfate (DSS)-treated mice restored colon length, decreased disease activity index (DAI), myeloperoxidase (MPO) enzyme activity and suppressed proinflammatory mediators. β-myrcene administration suppressed mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB) pathways to limit inflammation. β-myrcene also suppressed mRNA expression of proinflammatory chemokines in tumor necrosis factor-α (TNF-α) challenged HT-29 adenocarcinoma cells. In conclusion, β-myrcene administration suppresses colon inflammation by inhibiting MAP kinases and NF-κB pathways.

SARS-CoV-2 Infection and Outcomes in Children with Inflammatory Bowel Diseases: A Systematic Review

The impact of COVID-19 on pediatric patients with inflammatory bowel disease (PIBD) is still not clear and the knowledge acquired over the last 2 years is still evolving. This study aims to investigate the risk and clinical outcomes of COVID-19 in patients with PIBD. A systematic search of PubMed and Scopus databases was conducted to identify studies published up until September 2022. Out of the 475 articles screened, 14 studies were included in the review. Of the 4006 children with PIBD included, 390 (9.7%) tested positive for COVID-19. Among those with COVID-19, 5.9% (0-16.7%) needed hospitalization, 0.6% (0-1%) were admitted to the pediatric intensive care unit (PICU), and no deaths were reported. Among the included studies, only four presented details regarding patients' symptoms, with 21% (0-25%) presenting gastrointestinal (GI) symptoms. An association between PIBD activity or specific treatment and COVID-19 outcome could not be established. The prevalence of COVID-19 in patients with PIBD was low; therefore, the initial concerns regarding higher infection risk and worse prognosis in this population are not supported by the currently available data. Further research is needed to determine the natural history of the infection and the optimal treatment for these patients. Much is still unclear and additional studies should be performed in order to optimize prevention and care for this special group of patients.

Transanal ileal pouch anal anastomosis for ulcerative colitis in children and adults: a systematic review and meta-analysis

PURPOSE

The incidence of pediatric onset ulcerative colitis (UC) is increasing, with increasing rate of children eventually requiring surgical treatment. Total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the preferred surgical treatment. Although transanal IPAA (ta-IPAA) is becoming widely accepted for adult UC patients, data regarding this procedure in children are scarce. Nevertheless, some adult publications also include patients under 18 years old. This systematic review and meta-analysis aimed to summarize surgical and functional outcomes following ta-IPAA, and extract conclusion regarding pediatric UC patients.

METHODS

PubMed, Cochrane Library databases, Embase, Web of science and Google Scholar databases were searched, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses [PRISMA] guidelines. The final search was updated in April 2022. Four comparative cohorts (n = 868) and 11 non-comparative case series (n = 241) were included. Six reports included children. Anastomotic leak, complications, operative time, conversion rate, length of stay and functional outcomes were examined.

RESULTS

A total of 1103 patients, ranging 9-79 years were included in this review. We found no difference in risk for anastomotic leak (OR 1.36, 95% CI 0.46-4.06), minor and major complications (OR 0.92, 95% CI 0.48-1.76 and OR 0.78 95% CI 0.36-1.69, respectively) comparing ta-IPAA to transabdominal IPAA. Short- and long-term follow-up showed satisfying functional outcomes and quality of life.

CONCLUSIONS

Our review suggests that ta-IPAA is not inferior to transabdominal IPAA. Implementation of this method in children is technically feasible due to familiarity with the dissection plane. Long-term functional outcomes and quality of life are paramount in the pediatric population and should be particularly investigated. Multicenter prospective studies are required to investigate pediatric UC patients undergoing ta-IPAA.

Gastrointestinal Disorders in Adolescents and Young Adults: Preparing for a Smooth Transition to Adult-Centered Care

Chronic gastrointestinal disorders are prevalent in youth worldwide. The chronicity of these conditions often results in their persistence into adulthood. Challenges typically faced by young people transitioning to adulthood are often exacerbated in those with chronic gastrointestinal disease. Increased awareness of these challenges among health care professionals and appropriate policies and procedures for health care transition are critical. This article summarizes research on the challenges faced by emerging adults with the gastrointestinal disease during the transition to adult care. Barriers to optimal transitional care and current guidelines are discussed and used to offer practical recommendations for health care professionals working with this population.

Null Function of Npr1 Disturbs Immune Response in Colonic Inflammation During Early Postnatal Stage

Natriuretic peptide receptor 1 (NPR1) is conventionally known as a regulator of vascular homeostasis. Here, we generated an Npr1 knockout mouse model with CRISPR/Cas9 technology and found that homozygous mice (Npr1-/-) exhibited weight loss and poor survival rate during early postnatal stage. Careful examination revealed unexpectedly that Npr1-/- mice developed colitis characterized by shortened colon, evident colonic mucosal damage, increased histopathological score, and higher colonic expression of proinflammatory cytokines interleukin-1B (IL1B) and -6 (IL6). RNA-sequencing analysis revealed that differentially expressed genes were prominently enriched in the biological pathways related to immune response in both spleen and colon of Npr1-/- mice. Cytofluorimetric analysis demonstrated that leukocytes in the spleen were significantly increased, particularly, the populations of neutrophil and CD3+ T cell were elevated but CD4+ T cells were decreased in Npr1-/- mice. Administration of 8-Br-cGMP, a downstream activator of NPR1, restored these immune-cell populations disturbed in Npr1-/- mice and lessened the colitis-related phenotypes. To validate the involvement of Npr1 in colitis, we examined another mouse model induced by dextran sodium sulfate (DSS) and found a decreased Npr1 expression and shifted immune-cell populations as well. Importantly, 8-Br-cGMP treatment exhibited a similar effect in the restoration of immune-cell populations and attenuation of colonic inflammation in DSS mice. Our data indicate that loss of Npr1 possibly interrupts immune response, which is critical to the pathogenesis of colitis in the early life.

Probiotics and gastrointestinal diseases

During the past decades, scientists have discovered the intimate role of the gut microbiome in human health, and since then, several papers have been published to investigate if the use of biotics (probiotics, prebiotics, synbiotics, and postbiotics) may have a beneficial impact on human health both in treatment and prevention. We now ask ourselves whether we have reached the finish line or just a new starting point, as the evidence supporting the use of biotics in several conditions still needs a lot of work. Many questions remain unanswered today because the evidence differs depending on the indication, used strain, and amount and duration of administration. Herein we will summarize the evidence on probiotics in some gastrointestinal diseases such as infantile colic, functional abdominal pain disorders, celiac disease, acute gastroenteritis, inflammatory bowel disease, and Helicobacter pylori infection.