Phenotypic Variation in Paediatric Inflammatory Bowel Disease by Age: A Multicentre Prospective Inception Cohort Study of the Canadian Children IBD Network

Landscape of TPMT and NUDT15 Pharmacogenetic Variation in a Cohort of Canadian Pediatric Inflammatory Bowel Disease Patients

BACKGROUND

Patients with inflammatory bowel disease (IBD) exhibit considerable interindividual variability in medication response, highlighting the need for precision medicine approaches to optimize and tailor treatment. Pharmacogenetics (PGx) offers the ability to individualize dosing by examining genetic factors underlying the metabolism of medications such as thiopurines. Pharmacogenetic testing can identify individuals who may be at risk for thiopurine dose-dependent adverse reactions including myelosuppression. We aimed to evaluate PGx variation in genes supported by clinical guidelines that inform dosing of thiopurines and characterize differences in the distribution of actionable PGx variation among diverse ancestral groups.

METHODS

Pharmacogenetic variation in TPMT and NUDT15 was captured by genome-wide genotyping of 1083 pediatric IBD patients from a diverse Canadian cohort. Genetic ancestry was inferred using principal component analysis. The proportion of PGx variation and associated metabolizer status phenotypes was compared across 5 genetic ancestral groups within the cohort (Admixed American, African, East Asian, European, and South Asian) and to prior global estimates from corresponding populations.

RESULTS

Collectively, 11% of the cohort was categorized as intermediate or poor metabolizers of thiopurines, which would warrant a significant dose reduction or selection of alternate therapy. Clinically actionable variation in TPMT was more prevalent in participants of European and Admixed American/Latino ancestry (8.7% and 7.5%, respectively), whereas variation in NUDT15 was more prevalent in participants of East Asian and Admixed American/Latino ancestry (16% and 15% respectively).

CONCLUSIONS

These findings demonstrate the considerable interpopulation variability in PGx variation underlying thiopurine metabolism, which should be factored into testing diverse patient populations.

Pre-Diagnosis Diet Predicts Response to Exclusive Enteral Nutrition and Correlates with Microbiome in Pediatric Crohn Disease

Exclusive enteral nutrition (EEN) is effective in inducing remission in pediatric Crohn disease (CD). EEN alters the intestinal microbiome, but precise mechanisms are unknown. We hypothesized that pre-diagnosis diet establishes a baseline gut microbiome, which then mediates response to EEN. We analyzed prospectively recorded food frequency questionnaires (FFQs) for pre-diagnosis dietary patterns. Fecal microbiota were sequenced (16SrRNA) at baseline and through an 18-month follow-up period. Dietary patterns, Mediterranean diet adherence, and stool microbiota were associated with EEN treatment outcomes, disease flare, need for anti-tumor necrosis factor (TNF)-α therapy, and long-term clinical outcomes. Ninety-eight patients were included. Baseline disease severity and microbiota were associated with diet. Four dietary patterns were identified by FFQs; a "mature diet" high in fruits, vegetables, and fish was linked to increased baseline microbial diversity, which was associated with fewer disease flares (p < 0.05) and a trend towards a delayed need for anti-TNF therapy (p = 0.086). Baseline stool microbial taxa were increased (Blautia and Faecalibacterium) or decreased (Ruminococcus gnavus group) with the mature diet compared to other diets. Surprisingly, a "pre-packaged" dietary pattern (rich in processed foods) was associated with delayed flares in males (p < 0.05). Long-term pre-diagnosis diet was associated with outcomes of EEN therapy in pediatric CD; diet-microbiota and microbiota-outcome associations may mediate this relationship.

Surgical management of complicated Crohn's disease

Surgical management of pediatric Crohn's disease is fundamentally palliative, aiming to treat the sequalae of complicated disease while preserving intestinal length. Multidisciplinary discussion of risk factors and quality of life should take place prior to operative intervention. Though the surgical management of pediatric Crohn's disease is largely based on the adult literature, there are considerations specific to the pediatric population - notably disease and treatment effects on growth and development. Intrabdominal abscess is approached with percutaneous drainage when feasible, reserving surgical intervention for the patient who is unstable or failing medical therapy. Pediatric patients with fibrostenotic disease should be considered for strictureplasty when possible, for maximum preservation of bowel length. Patients with medically refractory Crohn's proctocolitis should be treated initially with fecal diversion without proctocolectomy.

Pan-enteric Capsule Endoscopy to Characterize Crohn's Disease Phenotypes and Predict Clinical Outcomes in Children and Adults: The Bomiro Study

BACKGROUND

Pan-enteric capsule endoscopy (PCE) provides useful information for the management of Crohn's disease (CD), especially in children. No study has evaluated the ability of PCE to characterize CD phenotypes and outcomes in children and adults.

METHODS

In a prospective multicenter observational study, we recruited patients with CD >6 years from 4 centers in Italy. Patients underwent clinical, biomarker assessment and PCE. Lesions were graded using the PCE system. For each segment, the most common lesion (MCL), the most severe lesion (MSL), and the extent of involvement were defined. Disease severity, extent, and clinical outcomes were compared between children and adults. A logistic regression analysis was used to identify predictive factors for negative outcomes in both age groups.

RESULTS

One hundred ninety-four consecutive patients (adults/children: 144/50) were evaluated for a total of 249 procedures. Children were more likely to have extensive disease, particularly in the colon. Higher MCL scores were independently associated with treatment escalation (odds ratio [OR], 4.09; 95% CI, 1.80-9.25; P = .001), while >30% disease extent was more indicative of clinical and endoscopic relapse (OR, 2.98; 1.26-7.08; P = .013). Disease extent was the only factor associated with endoscopic recurrence in children (OR, 4.50; 95% CI, 1.47-13.77; P = .008), while severe lesions in adults provided a better predictor of treatment escalation (OR, 4.31; 95% CI, 1.52-12.1; P = .006). Postexamination, PCE contributed to a change of therapy in 196/249 (79%) of the procedures.

CONCLUSIONS

PCE allowed the characterization of CD phenotypes in children and adults by assessing disease severity and extent, which are of different importance in predicting clinical outcomes in these age groups.

Imaging and endoscopic tools in pediatric inflammatory bowel disease: What's new?

Pediatric inflammatory bowel disease (IBD) is a chronic inflammatory disorder, with increasing incidence and prevalence worldwide. There have been recent advances in imaging and endoscopic technology for disease diagnosis, treatment, and monitoring. Intestinal ultrasound, including transabdominal, transperineal, and endoscopic, has been emerging for the assessment of transmural bowel inflammation and disease complications (e.g., fistula, abscess). Aside from surgery, IBD-related intestinal strictures now have endoscopic treatment options including through-the-scope balloon dilatation, injection, and needle knife stricturotomy and new evaluation tools such as endoscopic functional lumen imaging probe. Unsedated transnasal endoscopy may have a role in patients with upper gastrointestinal Crohn's disease or those with IBD with new upper gastrointestinal symptoms. Improvements to dysplasia screening in pediatric patients with longstanding colonic disease or primary sclerosing cholangitis hold promise with the addition of virtual chromoendoscopy and ongoing research in the field of artificial intelligence-assisted endoscopic detection. Artificial intelligence and machine learning is a rapidly evolving field, with goals of further personalizing IBD diagnosis and treatment selection as well as prognostication. This review summarized these advancements, focusing on pediatric patients with IBD.

Recommendations for Standardizing MRI-based Evaluation of Perianal Fistulizing Disease Activity in Pediatric Crohn's Disease Clinical Trials

BACKGROUND

Perianal fistulas and abscesses occur commonly as complications of pediatric Crohn's disease (CD). A validated imaging assessment tool for quantification of perianal disease severity and activity is needed to evaluate treatment response. We aimed to identify magnetic resonance imaging (MRI)-based measures of perianal fistulizing disease activity and study design features appropriate for pediatric patients.

METHODS

Seventy-nine statements relevant to MRI-based assessment of pediatric perianal fistulizing CD activity and clinical trial design were generated from literature review and expert opinion. Statement appropriateness was rated by a panel (N = 15) of gastroenterologists, radiologists, and surgeons using modified RAND/University of California Los Angeles appropriateness methodology.

RESULTS

The modified Van Assche Index (mVAI) and the Magnetic Resonance Novel Index for Fistula Imaging in CD (MAGNIFI-CD) were considered appropriate instruments for use in pediatric perianal fistulizing disease clinical trials. Although there was concern regarding the use of intravascular contrast material in pediatric patients, its use in clinical trials was considered appropriate. A clinically evident fistula tract and radiologic disease defined as at least 1 fistula or abscess on pelvic MRI were considered appropriate trial inclusion criteria. A coprimary clinical and radiologic end point and inclusion of a patient-reported outcome were also considered appropriate.

CONCLUSION

Outcomes of treatment of perianal fistulizing disease in children must include MRI. Existing multi-item measures, specifically the mVAI and MAGNIFI-CD, can be adapted and used for children. Further research to assess the operating properties of the indices when used in a pediatric patient population is ongoing.

Outcomes Following Acute Severe Colitis at Initial Presentation: A Multi-centre, Prospective, Paediatric Cohort Study

AIM

To assess contemporary outcomes in children with acute severe ulcerative colitis [ASUC] at initial presentation.

METHODS

Between April 2014 and January 2019, children aged <17 years, with new onset ASUC (Paediatric Ulcerative Colitis Activity Index [PUCAI ≥65) were prospectively followed in a Canadian inception cohort study. 16S rRNA amplicon sequencing captured microbial composition of baseline faecal samples. Primary endpoint was corticosteroid-free clinical remission with intact colon at 1 year [PUCAI <10, no steroids ≥4 weeks].

RESULTS

Of 379 children with new onset UC/IBD-unclassified, 105 [28%] presented with ASUC (42% male; median [interquartile range; [IQR]) age 14 [11-16] years; extensive colitis in all). Compared with mild UC, gut microbiome of ASUC patients had lower α-diversity, decreased beneficial anaerobes, and increased aerobes; 54 [51%] children were steroid-refractory and given infliximab [87% intensified regimen]. Corticosteroid-free remission at 1 year was achieved by 62 [61%] ASUC cohort (by 34 [63%] steroid-refractory patients, all on biologics; by 28 [55%] steroid responders,13 [25%] on 5- aminosalicylic acid [5-ASA], 5 [10%] on thiopurines, 10 [20%] on biologics). By 1 year, 78 [74%] escalated to infliximab including 24 [47%] steroid-responders failed by 5-ASA and/or thiopurines. In multivariable analysis, clinical predictors for commencing infliximab included hypoalbuminaemia, greater PUCAI, higher age, and male sex. Over 18 months, repeat corticosteroid course[s] and repeat hospitalisation were less likely among steroid-refractory versus -responsive but -dependent patients (adjusted odds ratio [aOR] 0.71 [95% CI 0.57-0.89] and 0.54 [95% CI 0.45-0.66], respectively).

CONCLUSION

The majority of children presenting with ASUC escalate therapy to biologics. Predictors of need for advanced therapy may guide selection of optimal maintenance therapy.

Health Services Utilization and Specialist Care in Pediatric Inflammatory Bowel Disease: A Multiprovince Population-Based Cohort Study

BACKGROUND

Patterns of health services utilization among children with inflammatory bowel disease (IBD) are important to understand as the number of children with IBD continues to increase. We compared health services utilization and surgery among children diagnosed <10 years of age (Paris classification: A1a) and between 10 and <16 years of age (A1b).

METHODS

Incident cases of IBD diagnosed <16 years of age were identified using validated algorithms from deterministically linked health administrative data in 5 Canadian provinces (Alberta, Manitoba, Nova Scotia, Ontario, Quebec) to conduct a retrospective cohort study. We compared the frequency of IBD-specific outpatient visits, emergency department visits, and hospitalizations across age groups (A1a vs A1b [reference]) using negative binomial regression. The risk of surgery was compared across age groups using Cox proportional hazards models. Models were adjusted for sex, rural/urban residence location, and mean neighborhood income quintile. Province-specific estimates were pooled using random-effects meta-analysis.

RESULTS

Among the 1165 (65.7% Crohn's) children with IBD included in our study, there were no age differences in the frequency of hospitalizations (rate ratio [RR], 0.88; 95% confidence interval [CI], 0.74-1.06) or outpatient visits (RR, 0.95; 95% CI, 0.78-1.16). A1a children had fewer emergency department visits (RR, 0.70; 95% CI, 0.50-0.97) and were less likely to require a Crohn's-related surgery (hazard ratio, 0.49; 95% CI, 0.26-0.92). The risk of colectomy was similar among children with ulcerative colitis in both age groups (hazard ratio, 0.71; 95% CI, 0.49-1.01).

CONCLUSIONS

Patterns of health services utilization are generally similar when comparing children diagnosed across age groups.

Variation in the Care of Children with Inflammatory Bowel Disease Within and Across Canadian Provinces: A Multi-Province Population-Based Cohort Study

Purpose

The incidence of childhood-onset inflammatory bowel disease (IBD) is rising. We described variation in health services utilization and need for surgery among children with IBD between six and 60 months following IBD diagnosis across Canadian pediatric centers and evaluated the associations between care provided at diagnosis at each center and the variation in these outcomes.

Patients and Methods

Using population-based deterministically-linked health administrative data from four Canadian provinces (Alberta, Manitoba, Nova Scotia, Ontario) we identified children diagnosed with IBD <16 years of age using validated algorithms. Children were assigned to a pediatric center of care using a hierarchical approach based on where they received their initial care. Outcomes included IBD-related hospitalizations, emergency department (ED) visits, and IBD-related abdominal surgery occurring between 6 and sixty months after diagnosis. Mixed-effects meta-analysis was used to pool results and examine the association between center-level care provision and outcomes.

Results

We identified 3784 incident cases of pediatric IBD, of whom 2937 (77.6%) were treated at pediatric centers. Almost a third (31.4%) of children had ≥1 IBD-related hospitalization and there were 0.66 hospitalizations per person during follow-up. More than half (55.8%) of children had ≥1 ED visit and there were 1.64 ED visits per person. Between-center heterogeneity was high for both outcomes; centers where more children visited the ED at diagnosis had more IBD-related hospitalizations and more ED visits during follow-up. Between-center heterogeneity was high for intestinal resection in Crohn's disease but not colectomy in ulcerative colitis.

Conclusion

There is variation in health services utilization among children with IBD and risk of undergoing intestinal resection in those with Crohn's disease, but not colectomy among children with ulcerative colitis, across Canadian pediatric tertiary-care centers. Improvements in clinical care pathways are needed to ensure all children have equitable and timely access to high quality care.

Recent developments in the assessment and management of inflammatory bowel disease in childhood: a narrative review

Background and Objective

The landscape of paediatric inflammatory bowel disease (pIBD) continues to evolve in an era of increasing incidence. There have been rapid developments in understanding, as we begin to perceive IBD as a spectrum of conditions, alongside advancements in monitoring and treatment. The objective of this article was to provide an overview of recent advances and challenges in the management of pIBD, with a focus on sustainable healthcare, personalised therapy, genomics, new drugs and avenues for future optimisation.

Methods

We present a narrative review that synthesises and summarises recent research (2017-2022) related to pIBD. We undertook a structured search of the literature (PubMed and Medline) and additional articles were identified through manual searches of reference lists. Evidence tables were compiled for disease outcomes.

Key Content and Findings

In this review we outline current practice, integrating clinical guidelines and contemporary research. We discuss initial investigations (including suggested threshold for paediatric faecal calprotectin), specialist investigations for disease monitoring [with reference to video capsule endoscopy (VCE) and therapeutic drug levels] and outline new and established treatment options. Biomarkers and genomic testing are examined as important tools for individualising care and identifying potential therapeutic targets, including for top-down therapy. Despite these advances, significant challenges remain, including the need for further research to understand the mechanisms of disease and the translation of these advances into real-world improvements in practice.

Conclusions

Recent advances in understanding of the pathogenesis of pIBD, alongside genomic and pharmacological developments have added more tools to the armamentarium for the treatment of these conditions and highlighted ongoing areas of research need.

Predicting pediatric Crohn's disease based on six mRNA-constructed risk signature using comprehensive bioinformatic approaches

Crohn's disease (CD) is a recurrent, chronic inflammatory condition of the gastrointestinal tract which is a clinical subtype of inflammatory bowel disease for which timely and non-invasive diagnosis in children remains a challenge. A novel predictive risk signature for pediatric CD diagnosis was constructed from bioinformatics analysis of six mRNAs, adenomatosis polyposis downregulated 1 (APCDD1), complement component 1r, mitogen-activated protein kinase kinase kinase kinase 5 (MAP3K5), lysophosphatidylcholine acyltransferase 1, sphingomyelin synthase 1 and transmembrane protein 184B, and validated using samples. Statistical evaluation was performed by support vector machine learning, weighted gene co-expression network analysis, differentially expressed genes and pathological assessment. Hematoxylin-eosin staining and immunohistochemistry results showed that APCDD1 was highly expressed in pediatric CD tissues. Evaluation by decision curve analysis and area under the curve indicated good predictive efficacy. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and gene set enrichment analysis confirmed the involvement of immune and cytokine signaling pathways. A predictive risk signature for pediatric CD is presented which represents a non-invasive supplementary tool for pediatric CD diagnosis.

The 2023 Impact of Inflammatory Bowel Disease in Canada: Special Populations-Children and Adolescents with IBD

Rates of inflammatory bowel disease (IBD) in Canadian children and adolescents are among the highest in the world, and the incidence is rising most rapidly in children under five years of age. These young children may have either a typical form of IBD with multi-factorial aetiology, or they may have a monogenic form. Despite the growing number of children in Canada living with this important chronic disease, there are few available medical therapies approved by Health Canada due to the omission of children from most clinical trials of newly developed biologics. As a result, off-label use of medications is common, and physicians have learned to use existing therapies more effectively. In addition, most Canadian children are treated in multidisciplinary, specialty clinics by physicians with extra training or experience in IBD, as well as specialist nurses, dietitians, mental health care providers and other allied health professionals. This specialized clinic approach has facilitated cutting edge research, led by Canadian clinicians and scientists, to understand the causes of IBD, the optimal use of therapies, and the best ways to treat children from a biopsychosocial perspective. Canadians are engaged in work to understand the monogenic causes of IBD; the interaction between genes, the environment, and the microbiome; and how to address the mental health concerns and medical needs of adolescents and young adults transitioning from paediatric to adult care.

Endoscopic Balloon Dilatation in Pediatric Crohn Disease: An IBD Porto Group Study

OBJECTIVE/BACKGROUND

Endoscopic balloon dilatation (EBD) has been shown to be effective and safe in adults with stricturing Crohn disease (CD) yet pediatric data is sparse. We aimed to assess efficacy and safety of EBD in stricturing pediatric CD.

METHODS

International collaboration included 11 centers from Europe, Canada, and Israel. Recorded data included patient demographics, stricture features, clinical outcomes, procedural adverse events, and need for surgery. Primary outcome was surgery-free over 12 months and secondary outcomes were clinical response and adverse events.

RESULTS

Eighty-eight dilatations were performed over 64 dilatation series in 53 patients. Mean age at CD diagnosis was 11.1 (±4.0) years, stricture length 4 cm [interquartile range (IQR) 2.8-5], and bowel wall thickness 7 mm (IQR 5.3-8). Twelve of 64 (19%) patients underwent surgery in the year following the dilatation series, at a median of 89 days (IQR 24-120; range 0-264) following EBD. Seven of 64 (11%) had subsequent unplanned EBD over the year, of whom two eventually underwent surgical resection. Two of 88 (2%) perforations were recorded, 1 of whom was managed surgically, and 5 patients had minor adverse events managed conservatively. There was a significant improvement in all clinical measures following EBD with weighted pediatric CD activity index-defined remission increasing from 13% at baseline to 44%, 46%, and 61%, and absence of obstructive symptoms in 55%, 53%, and 64% of patients at week 2, 8, and 24 respectively.

CONCLUSIONS

In this largest study of EBD in pediatric stricturing CD to date, we demonstrated that EBD is effective in relieving symptoms and avoiding surgery. Adverse events rates were low and consistent with adult data.

Advances in Endoscopy for Pediatric Inflammatory Bowel Disease

Endoscopic characterization of pediatric inflammatory bowel disease (IBD) has developed in accordance with advances in treatment and improved understanding of disease progression and complications. Reliable and consistent endoscopic reporting practices and tools continue to evolve. The roles of endoscopic ultrasonography, capsule endoscopy, and deep enteroscopy in the care of children and adolescents with IBD are beginning to be clarified. Opportunities for therapeutic intervention with endoscopy in pediatric IBD, including endoscopic balloon dilation and electroincision therapy, require further study. This review discusses the current utility of endoscopic assessment in Pediatric Inflammatory Bowel Disease, as well as emerging and evolving techniques to improve patient care.

A comparison of the Child Health Utility 9D and the Health Utilities Index for estimating health utilities in pediatric inflammatory bowel disease

PURPOSE

Health utilities are challenging to ascertain in children and have not been studied in pediatric Crohn's disease (CD) and ulcerative colitis (UC). The objective was to assess discriminative validity by comparing utilities elicited using the Child Health Utility-9 Dimension (CHU9D) to the Health Utilities Index (HUI) across multiple disease activity scales in pediatric UC and CD.

METHODS

Preference-based instruments were administered to 188 children with CD and 83 children with UC aged 6 to 18 years. Utilities were calculated using CHU9D adult and youth tariffs, and HUI2 and HUI3 algorithms in children with inactive (quiescent) and active (mild, moderate, and severe) disease. Differences between instruments, tariff sets and disease activity categories and were tested statistically.

RESULTS

In CD and UC, all instruments detected significantly higher utilities for inactive compared to active disease (p < 0.05). Mean utilities for quiescent disease ranged from 0.810 (SD 0.169) to 0.916 (SD 0.121) in CD and from 0.766 (SD 0.208) to 0.871 (SD 0.186) in UC across instruments. Active disease mean utilities ranged from 0.694 (SD 0.212) to 0.837 (SD 0.168) in CD and from 0.654 (SD 0.226) to 0.800 (SD 0.128) in UC.

CONCLUSION

CHU9D and HUI discriminated between levels of disease activity in CD and UC regardless of the clinical scale used, with the CHU9D youth tariff most often displaying the lowest utilities for worse health states. Distinct utilities for different IBD disease activity states can be used in health state transition models evaluating the cost-effectiveness of treatments for pediatric CD and UC.

Paediatric Inflammatory Bowel Disease: A Multi-Stakeholder Perspective to Improve Development of Drugs for Children and Adolescents

BACKGROUND AND AIMS

Despite recent approvals for new drugs to treat adults with Crohn's disease or ulcerative colitis, there are only two approved advanced treatment options [infliximab and adalimumab] for children with inflammatory bowel disease [IBD]. There are many potential new therapies being developed for adult and paediatric IBD. Moreover, regulatory agencies in both the European Union and USA have processes in place to support the early planning and initiation of paediatric studies. Nevertheless, unacceptable delays in approvals for use of drugs in children persist, with an average 7-year gap, or longer, between authorization of new IBD drugs for adults and children.

METHODS

A 2-day virtual meeting was held during April 14-15, 2021 for multi-stakeholders [clinical academics, patient community, pharmaceutical companies and regulators] to discuss their perspectives on paediatric drug development for IBD.

RESULTS

The multi-stakeholder group presented, discussed and proposed actions to achieve expediting the approval of new drugs in development for paediatric IBD.

CONCLUSIONS

Collaborative action points for all stakeholders are required to make progress and facilitate new drug development for children with IBD.

Clinical Features of Crohn's Disease Stratified by Age at Diagnosis According to Montreal Classification

Aim

The differences of clinical characteristics stratified by age at diagnosis especially according to Montreal classification were rarely studied in China. This study aimed to evaluate and compare the clinical features in various groups of CD patients stratified by age at diagnosis.

Methods

A cross-sectional study of CD patients was conducted through a stratified sampling according to Montreal classification. Patients were divided into three groups by age at diagnosis: group A1 (<17 years old), group A2 (17 to 40 years old), and group A3 (>40 years old). The clinical characteristics, laboratory tests, radiographic, and endoscopic features were analyzed by statistics.

Results

We enrolled 259 CD patients for the study. There was male predominance under 40 years old. Compared to group A1, more female patients were presented in group A3. There were more patients had perianal fistulas in group A1 compared to group A2 and group A3. Compared with group A1, patients in group A2 were associated with lower total protein (TP) levels. The mean TP and platelet count (PC) levels in group A3 were lower than group A1. Patients in group A1 had a lower rate of stricturing (B2) disease behavior than group A2 and group A3, and patients in group A3 who had a B2 disease behavior were higher than group A2. Those differences could guide early treatment or inventions for CD patients who might progress to a more complex disease behavior.

Conclusion

CD patients stratified by age at diagnosis according to Montreal classification had different clinical symptoms, laboratory test results as well as disease locations and behaviors.

Phenotype and outcomes of very early onset and early onset inflammatory bowel diseases in a Montreal pediatric cohort

Objectives

The incidence of very-early-onset inflammatory bowel disease (VEO-IBD) and early-onset IBD (EO-IBD) is increasing. Here, we report their phenotype and outcomes in a Montreal pediatric cohort.

Methods

We analyzed data from patients diagnosed with IBD between January 2014 and December 2018 from the CHU Sainte-Justine. The primary endpoint was to compare the phenotypes of VEO-IBD and EO-IBD. The secondary endpoints involved comparing outcomes and rates of steroid-free clinical remission (SFCR) at 12 (±2) months (m) post-diagnosis and at last follow-up.

Results

28 (14 males) and 67 (34 males) patients were diagnosed with VEO-IBD and EO-IBD, respectively. Crohn's disease (CD) was more prevalent in EO-IBD (64.2% vs. 39.3%), whereas unclassified colitis (IBD-U) was diagnosed in 28.6% of VEO-IBD vs. 10.4% of EO-IBD (p < 0.03). Ulcerative colitis (UC) and IBD-U predominantly presented as pancolitis in both groups (VEO-IBD: 76.5% vs. EO-IBD: 70.8%). Combining all disease subtypes, histological upper GI lesions were found in 57.2% of VEO-IBD vs. 83.6% of EO-IBD (p < 0.009). In each subtype, no differential histological signature (activity, eosinophils, apoptotic bodies, granulomas) was observed between both groups. At 12 m post-diagnosis, 60.8% of VEO-IBD and 62.7% of EO-IBD patients were in SFCR. At a median follow-up of 56 m, SFCR was observed in 85.7% of VEO-IBD vs. 85.0% of EO-IBD patients.

Conclusion

The rate of patients in SFCR at 1-year post-diagnosis and at the end of follow-up did not significantly differ between both groups.

Infantile-onset inflammatory bowel disease has variable long-term outcomes

Objective and aim

Infantile-onset inflammatory bowel disease (IO-IBD), defined as IBD diagnosed at age 2 years or younger, tends to be more severe and refractory to conventional treatment than IBD diagnosed at a later age. However, data about IO-IBD and its long-term follow up are limited. We thus aimed to evaluate the presentation and long-term outcomes of patients with IO-IBD in a retrospective multicenter study.

Methods

Medical records of patients diagnosed with IO-IBD in eight medical centers during 2000-2017 with at least 1-year follow up were reviewed. Demographics and disease characteristics at diagnosis including age of onset, disease phenotype and location, surgeries, medical therapy, and comorbid conditions were recorded.

Results

Twenty-three patients with IO-IBD (16 males, 70%) were identified and followed for a median (range) of 51.2 (26.0-110.3) months. The mean ages at presentation and at the last follow up were 14 ± 9.8 and 101 ± 77 months, respectively. Six (26%) patients needed ileostomy already at the time of diagnosis and 20 (87%) were treated with corticosteroids. During long-term follow up, remission was achieved in 16 (73%) patients; of whom, 3 (14%) were without medications and 7 (32%) were in remission with the use of 5-aminosalicylic acid only. One patient needed hemicolectomy and one developed a severe EBV related infection.

Conclusion

The majority of patients with IO-IBD achieved long-term remission, despite a severe disease presentation at diagnosis. Surgery rate however is high, mainly during the first months from diagnosis.

Diagnostic Delay in Pediatric Inflammatory Bowel Disease: A Systematic Review

INTRODUCTION

Delays in diagnosing pediatric inflammatory bowel disease (IBD) are common, but the extent of this delay remains unclear due to variations in reported time-periods between studies. The objectives of this systematic review were to examine the extent of diagnostic delay in pediatric IBD and examine any association between specific characteristics and length of diagnostic delay.

METHODS

We identified studies from several medical bibliographical databases (EMBASE, Medline and CINAHL) from their inception to April 2021. Studies examining pediatric cohorts (< 18 years old) defined as having a diagnosis of Crohn's Disease (CD), ulcerative colitis (UC), or by the more general definition of IBD, and reporting a median time-period between the onset of symptoms and a final diagnosis (diagnostic delay) were included. Two reviewers selected each study, extracted data, and assessed their quality using the Newcastle-Ottawa scale. Narrative synthesis was then used to examine the extent of overall diagnostic delay and delay associated with specific sample characteristics.

RESULTS

Of the 10,119 studies initially identified, 24 were included in the review. The overall median diagnostic delay range was 2-10.4 months for IBD, 2.0-18.0 months for UC and 4.0-24.0 months for CD. However, for approximately two thirds of UC (68.8%) and CD (66.7%) studies, delay ranged from 2.0-3.0 and 4.0-6.3 months, respectively. A longer delay was significantly associated with several sample characteristics; however, these were too infrequently examined to draw robust conclusion on their role.

CONCLUSION

Children continue to wait several months for a final diagnosis of IBD, and those with CD experience longer delay than those with UC. The role of specific characteristics on delay needs further exploration.

Progression to Anti-TNF Treatment in Very Early Onset Inflammatory Bowel Disease Patients

OBJECTIVES

Limited data are currently available regarding anti-tumor necrosis factor (TNF) use and outcomes in very early onset inflammatory bowel disease (VEOIBD) patients. We aimed to assess the long-term outcomes and time to progression to anti-TNF treatment in VEOIBD patients.

METHODS

We retrospectively reviewed IBD patients diagnosed under 6 years of age, between January 2005 and December 2019, from the British-Columbia (BC) Pediatric IBD database. Demographic data, disease characteristics, disease location and severity were documented. Data on anti-TNF treatment at initiation and during follow up including type of biologic, dosing, and response were collected. Kaplan-Meier curves were used to assess the number of years to progression to anti-TNF treatment and the parameters influencing commencement.

RESULTS

Eighty-nine patients with VEOIBD were diagnosed during the study period. Median age at diagnosis was 3.8 years [interquartile range (IQR) 2.6-5.1], 45.3% had Crohn disease (CD) and 62.8% were males. Median duration of follow up was 6.39 years (IQR 3.71-10.55). Anti-TNF treatment was started on 39.5% of patients and 7.0% underwent surgery. Rapid progression to biologic treatment was associated with Perianal fistulizing disease or stricturing disease in CD patients ( P = 0.026, P = 0.033, respectively), and disease severity ( P = 0.017) in ulcerative colitis(UC) patients. The median dose of infliximab at 1 year was 10 mg/kg (IQR 7.5-11) and a median dose interval of 4.5 weeks (IQR 4-6). Clinical remission was reported in 61.8% of patients on their first biologic agent.

CONCLUSIONS

The response rate was higher than previously reported and might be due to higher infliximab dosing with shorter infusion intervals than standard dosing.

SYSTEMATIC REVIEW AND META - ANALYSIS OF THE FREQUENCY AND RE-CLASSIFICATION TRENDS OF PEDIATRIC INFLAMMATORY BOWEL DISEASE - UNCLASSIFIED

BACKGROUND

The term inflammatory bowel disease-unclassified (IBDU) is used when an individual has chronic colitis but cannot be sub-typed into ulcerative colitis (UC) or Crohn's disease (CD) on the basis of the clinical, endoscopic, imaging and histopathological features. On follow-up a proportion of patients with IBDU are re-classified as CD or UC. There has been considerable variability in the frequency and reclassification rates of pediatric IBDU in published literature.

METHODS

PubMed and Scopus and were searched for publications related to Pediatric Inflammatory Bowel Disease (PIBD) published between Jan,2014 and July,2021. Two reviewers independently searched and selected studies reporting the frequency of IBDU and/or their re-classification. The pooled prevalence was expressed as proportion and 95%CI. Meta-analysis was performed using the inverse variance heterogeneity model.

RESULTS

A total of 2750 studies were identified through a systematic search of which 27 studies were included in this systematic review. The overall pooled frequency of IBDU (n=16064) was found to be 7.1% (95%CI 5.8-8.5%). There was no variation in IBDU frequency by geographical location. Seven studies (n=5880) were included in the IBDU re-classification analysis. Overall, 50% (95%CI 41-60%) children with IBDU were re-classified on follow-up. Amongst these 32.7% (95% 21-44%) were re-classified to UC and 17% (95%CI 12-22%) were re-classified to CD.

CONCLUSION

IBDU comprises 7.1% of PIBD at initial diagnosis. Half of these children are re-classified into UC or CD on follow-up with a higher likelihood of re-classification to UC as compared to CD.

Phenotypic Pattern of Early Versus Later-Onset Pediatric Inflammatory Bowel Disease in a Eurasian Country

OBJECTIVES

It is not clear whether the characteristics of pediatric inflammatory bowel disease (IBD) differ between Eastern and Western countries. The aim of this study was to analyze the characteristics of PIBD in Turkey, according to the age at diagnosis.

METHODS

The data of 176 children with IBD who were followed in our center were analyzed. Patients were divided into early (EO-IBD, onset at 2 to &lt;10 years) and later-onset (LO-IBD, 10 to ≤17 years) IBD according to the age at diagnosis. Patients' data with ulcerative colitis (UC) and Crohn's disease (CD) were compared.

RESULTS

Of 176 patients, 47 (26.7%) were diagnosed with EO-IBD. Patients with early-onset ulcerative colitis (EO-UC) had the highest rate of family history of IBD (17.6%). Pancolitis was the most common form of UC regardless of the age at onset. The rate of moderate-severe disease activity in later-onset UC (62.5%) was higher than in EO-UC (37.5%). A higher rate of extraintestinal manifestations was observed in EO-IBD patients, particularly in EO-UC (38.2%) than in LO-IBD patients. Patients with early-onset CD (EO-CD) had predominantly colonic involvement and nonstricturing, nonpenetrating disease behavior. The rate of perianal disease in patients with later-onset CD (LO-CD) (64.5%) was noticeably higher than those with EO-CD (23%).

CONCLUSIONS

Our results suggest that patients with EO-UC represented a distinct phenotype with a mild disease activity, high rate of extraintestinal symptoms, and a high proportion of family history. The analysis of our IBD cohort also demonstrated remarkably high rate of perianal disease, particularly in patients with LO-CD.

Prevalence, phenotype and medication for the pediatric inflammatory bowel disease population of a state in Southeastern Brazil

BACKGROUND

Inflammatory bowel disease (IBD) can lead to social and economic impacts worldwide. In Brazil, where its adult prevalence is increasing, the epidemiology of the pediatric population is not well known, although there is a documented increase in pediatric IBD incidence worldwide. Brazil has continental dimensions, and Espírito Santo is a state of southeastern Brazil, the region with the highest demographic densities and is the economically most important in the country.

AIM

To assess the prevalence, incidence, phenotype and medications in a Southeastern Brazilian pediatric population.

METHODS

Data were retrieved from the Public Medication-Dispensing System of the Department of Health in Espírito Santo state from documentation required to have access to highly expensive medication from August 1, 2012 to July 31, 2014. There were 1048 registered patients with IBD of all ages, and of these patients, the cases ≤ 17 years were selected. The data were obtained through the analysis of administrative requests for these medications and included medical reports, endoscopy exams, histopathology and imaging tests, which followed the Clinical Protocols and Therapeutic Guidelines of the Brazilian Government. Only confirmed cases of IBD were included in the study.

RESULTS

There were 55 pediatric patients/1048 registered patients (5.34%), with Crohn's disease (CD) representing 30/55 (55%), ulcerative colitis (UC) 24/55 (43.6%) and 1 unclassified IBD, a significant difference from adult patients (P = 0.004). The prevalence of IBD in pediatric patients was 5.02 cases/100.000 inhabitants; the incidence in 2014 was 1.36 cases/100.000 inhabitants. The mean age at diagnosis was 12.2 years (± 4.2). There were 7 children diagnosed up to 6 years old, 7 between 7 to 10 years old and 41 between 11 and ≤ 17 years old. There was no difference in the distribution of UC and CD between these age categories (P = 0.743). There was no difference in gender distribution in relation to adults. Children and adolescents with UC had a predominance of pancolitis, unlike adults (P = 0.001), and used aminosalicylates and immunomodulators for their treatment. Pediatric patients with CD did not present a difference in disease location but had a higher frequency of fistulizing behavior (P = 0.03) and perianal disease phenotype (P = 0.007) than adult patients. Patients with CD used more immunomodulators and biological therapy. Treatment with biological therapy was more frequently used in pediatric patients than in adults (P < 0.001).

CONCLUSION

Although the data from this study demonstrate that incidence and prevalence rates are low in southeastern Brazil, these data demonstrate the severity of IBD in pediatric patients, with the need for early diagnosis and therapy, avoiding serious damage.

Targeted Analysis of the Gut Microbiome for Diagnosis, Prognosis and Treatment Individualization in Pediatric Inflammatory Bowel Disease

We explored the fecal microbiota in pediatric patients <18 years of age with treatment-naïve IBD (80 Crohn’s disease (CD), 27 ulcerative colitis (UC)), in 50 non-IBD patients with gastrointestinal symptoms without inflammation and in 75 healthy children. Using a targeted qPCR approach, the quantities of more than 100 different bacterial species were measured. Results: The bacterial abundance was statistically significantly reduced in the IBD and non-IBD patients compared to the healthy children for several beneficial species. The CD patients had a lower abundance of Bifidobacterium species compared to the UC patients, and the IBD patients in need of biologic therapy had a lower abundance of butyrate producing bacteria. Based on the abundance of bacterial species at diagnosis, we constructed Diagnostic, Phenotype and Prognostic Indexes. Patients with a high Diagnostic Index had 2.5 times higher odds for having IBD than those with a lower index. The CD patients had a higher Phenotype Index than the UC patients. Patients with a high Prognostic Index had 2.1 higher odds for needing biologic therapy compared to those with a lower index. Conclusions: The fecal abundance of bacterial species can aid in diagnosing IBD, in distinguishing CD from UC and in identifying children with IBD in need of biologic therapy.

Epidemiological characteristics of Asian children with inflammatory bowel disease at diagnosis: Insights from an Asian-Pacific multi-centre registry network

BACKGROUND

There remains a dearth of Asian epidemiological literature for paediatric inflammatory bowel disease (PIBD).

AIM

To describe the presenting features of PIBD from 7 Asia-Pacific pediatric gastroenterology centers via a central standardised electronic data platform.

METHODS

Clinical, endoscopic and radiologic data at diagnosis from the registry were extracted between 1st January 1995 to 31st December 2019. Disease phenotypic characteristics were classified as per the Paris classification system.

RESULTS

There was a distinct rise in new PIBD cases: Nearly half (48.6%) of the cohort was diagnosed in the most recent 5 years (2015-2019). The ratio of Crohn's disease (CD):Ulcerative colitis (UC):IBD-Unclassified was 55.9%:38.3%:5.8%. The mean age was 9.07 years with a high proportion of very early onset IBD (VEO-IBD) (29.3%) and EO-IBD (52.7%). An over-representation of the Indian/South Asian ethnic group was observed which accounted for 37.0% of the overall Singapore/Malaysia subcohort (6.8%-9.0% Indians in census). Indian/South Asian CD patients were also most likely to present with symptomatic perianal disease (P = 0.003). CD patients presented with significantly more constitutional symptoms (fever, anorexia, malaise/fatigue and muscle-wasting) than UC and higher inflammatory indices (higher C-reactive protein and lower albumin levels).

CONCLUSION

We observed a high incidence of VEO-IBD and an over-representation of the Indian ethnicity. South Asian CD patients were more likely to have symptomatic perianal disease.

Twenty-first Century Trends in the Global Epidemiology of Pediatric-Onset Inflammatory Bowel Disease: Systematic Review

BACKGROUND & AIMS

The incidence of inflammatory bowel disease (IBD) is increasing internationally, particularly in nations with historically low rates. Previous reports of the epidemiology of pediatric-onset IBD identified a paucity of data. We systematically reviewed the global trends in incidence and prevalence of IBD diagnosed in individuals <21 years old over the first 2 decades of the 21st century.

METHODS

We systematically reviewed studies indexed in MEDLINE, EMBASE, Airiti Library, and SciELO from January 2010 to February 2020 to identify population-based studies reporting the incidence and/or prevalence of IBD, Crohn's disease, ulcerative colitis, and/or IBD-unclassified. Data from studies published before 2000 were derived from a previously published systematic review. We described the geographic distribution and trends in children of all ages and limiting to very early onset (VEO) IBD.

RESULTS

A total of 131 studies from 48 countries were included. The incidence and prevalence of pediatric-onset IBD is highest in Northern Europe and North America and lowest in Southern Europe, Asia, and the Middle East. Among studies evaluating trends over time, most (31 of 37, 84%) studies reported significant increases in incidence and all (7 of 7) reported significant increases in prevalence. Data on the incidence and prevalence of VEO-IBD are limited to countries with historically high rates of IBD. Time trends in the incidence of VEO-IBD were visually heterogeneous.

CONCLUSIONS

Rates of pediatric-onset IBD continue to rise around the world and data are emerging from regions where it was not previously reported; however, there remains a paucity of data on VEO-IBD and on pediatric IBD from developing and recently developed countries.

Epidemiological trends of pediatric IBD in Italy: A 10-year analysis of the Italian society of pediatric gastroenterology, hepatology and nutrition registry

INTRODUCTION

The present study aimed at evaluating Italian epidemiological trends of pediatric inflammatory bowel diseases (IBD) over the period 2009-2018.

MATERIALS AND METHODS

Data from 1969 patients enrolled in the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition Registry, by 49 pediatric IBD centers throughout the country, were analyzed, comparing three different time intervals (2009-2012, 2013-2015, 2016-2018).

RESULTS

The number of new IBD diagnoses ranged from 175 to 219 per year, evenly distributed over the examined period of time. From 2009 to 2018, the minimal incidence ranged from 1.59 to 2.04 /10⁵ inhabitants aged < 18 years, with an overall slight predominance of ulcerative colitis (UC) over Crohn's disease (CD) (ratio: 1.1). Mean diagnostic delay was 6.8 months for CD and 4.1 months for UC, with a significant reduction for CD when comparing the three-time intervals (p =0.008). The most frequent disease locations according to the Paris classification were ileocolonic for CD (41.3%) and pancolitis for UC (54.6%).

CONCLUSIONS

The minimal incidence rate in Italy seems to have stabilized over the last two decades, even if it has increased when compared to previous reports. UC is still slightly more prevalent than CD in our country. Diagnostic delay significantly decreased for CD, reflecting an improved diagnostic capacity.

Changes in the clinical phenotype and behavior of pediatric luminal Crohn's disease at diagnosis in the last decade

BACKGROUND AND AIMS

The aims of this study were to describe the trends in the behavior of pediatric CD during the last decade and to describe the seasonal variation of disease presentation.

METHODS

Patients under 18 years old and diagnosed between 2009 and 2019 were included. The clinical, endoscopic, histological, and laboratory data were collected from the medical records. We analyzed the trends of these parameters according to the year and season of diagnosis.

RESULTS

654 patients were included in the study. The number of incident CD cases increased yearly. Patients diagnosed between 2015 and 2019 were younger at diagnosis (OR 2.53, p = 0.02), had more perianal diseases (OR: 2.30, p < 0.0001) and more granulomas (OR: 1.61, p = 0.003), but fewer eosinophils (OR: 0.35, p < 0.0001) and less chronic lymphoplasmacytic infiltrate (OR: 0.56, p = 0.008) as compared to the 2009-2014 cohort. There was fewer CD diagnosis during winter. Patients diagnosed in the fall had lower PCDAIs, less failure to thrive and less extensive digestive involvement. Colonic disease was significantly more frequent during summer and fall.

CONCLUSION

The clinical and histological phenotype of CD has changed over time and there are important seasonal trends in the frequency and severity on disease behavior suggesting possible disease triggers.

Clinical Features and Long-Term Outcomes of Paediatric-Onset Inflammatory Bowel Disease in a Population-Based Cohort in the Songpa-Kangdong District of Seoul, Korea

BACKGROUND AND AIMS

The long-term outcomes of paediatric-onset inflammatory bowel disease [pIBD] in non-Caucasian populations are unknown. We therefore evaluated and compared the clinical features and long-term outcomes of pIBD with those of adult-onset IBD [aIBD] using a population-based cohort in the Songpa-Kangdong district of Seoul, Korea.

METHODS

Clinical characteristics and prognoses were compared between the two groups: pIBD [defined as <18 years of age at diagnosis] and aIBD [18-59 years of age at diagnosis].

RESULTS

We identified 131 patients with pIBD (48 ulcerative colitis [UC], 83 Crohn's disease [CD]) and 1192 patients with aIBD [866 UC, 326 CD] during 1986-2015. Extensive colitis at diagnosis was more prevalent in pUC than in aUC [45.8% vs 22.3%, p < 0.001], and the overall exposure to corticosteroids, thiopurines and anti-tumour necrosis factor agents was higher in pUC than in aUC [p < 0.001]. The cumulative risk of colectomy was higher in pUC than in aUC during a median follow-up of 125.0 and 112.1 months, respectively [8.9% vs 1.8% at 10 years after diagnosis, p = 0.030]. Ileocolonic location and inflammatory behaviour at diagnosis were more common in pCD than in aCD; however, patients with pCD and aCD did not differ regarding treatment or disease course during a median follow-up of 137.2 and 120.9 months, respectively.

CONCLUSION

Our study showed clear differences between pIBD and aIBD, especially in UC. pUC presents with more extensive diseases and may have a more severe disease course, as suggested by an earlier time to administering medications and performing colectomy.

Therapeutic Advances in Gut Microbiome Modulation in Patients with Inflammatory Bowel Disease from Pediatrics to Adulthood

There is mounting evidence that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease (IBD). For the past decade, high throughput sequencing-based gut microbiome research has identified characteristic shifts in the composition of the intestinal microbiota in patients with IBD, suggesting that IBD results from alterations in the interactions between intestinal microbes and the host’s mucosal immune system. These studies have been the impetus for the development of new therapeutic approaches targeting the gut microbiome, such as nutritional therapies, probiotics, fecal microbiota transplant and beneficial metabolic derivatives. Innovative technologies can further our understanding of the role the microbiome plays as well as help to evaluate how the different approaches in microbiome modulation impact clinical responses in adult and pediatric patients. In this review, we highlight important microbiome studies in patients with IBD and their response to different microbiome modulation therapies, and describe the differences in therapeutic response between pediatric and adult patient cohorts.

Prospective Evaluation of Endoscopic and Histologic Indices in Pediatric Ulcerative Colitis Using Centralized Review

INTRODUCTION

We aimed to evaluate the reliability and validity of the Ulcerative Colitis (UC) Endoscopic Index of Severity (UCEIS) and Mayo Endoscopy Score (MES) and to validate the Robarts Histopathology Index (RHI) and Nancy Index (NI) in pediatric UC. We examined rectosigmoid and pancolonic versions of each instrument.

METHODS

Single-center cross-sectional study of 60 prospectively enrolled participants. Through central endoscopy review, 4 pediatric gastroenterologists assigned rectosigmoid and pancolonic (mean of 5 colonic segments) UCEIS and MES scores. Two blinded pathologists assigned rectosigmoid and pancolonic RHI and NI scores. We assessed reliability with intraclass correlation coefficients and weighted kappa statistics and explored construct validity with correlations, boxplots, and receiver operator characteristic curves.

RESULTS

The UCEIS and MES displayed almost perfect intra-rater and inter-rater reliability (intraclass correlation coefficient and weighted kappa ≥0.85), moderate-to-strong correlation with histologic/clinical activity and fecal calprotectin (FC), and very strong correlation with global endoscopic severity (r > 0.9). Rectosigmoid UCEIS and MES scores of 0 were highly specific (≥95%) for endoscopic and histologic remission throughout the colon. Pancolonic endoscopy scores correlated more strongly with histologic activity, clinical activity, and systemic inflammatory markers and better discriminated between degrees of active disease. RHI and NI showed moderate-to-strong correlation (r = 0.5-0.83) with endoscopic/clinical activity and FC.

DISCUSSION

Our findings support the reliability and construct validity of the UCEIS and MES and the construct validity of the RHI and NI in pediatric UC. Normal rectosigmoid findings predicted pancolonic healing, but, given active disease, pancolonic endoscopic assessment more accurately captured global disease burden.

One-year outcomes with ustekinumab therapy in infliximab-refractory paediatric ulcerative colitis: a multicentre prospective study

BACKGROUND

The phase 3 (UNIFI) trial of ustekinumab (anti-interleukin 12/23) demonstrated efficacy even after prior biologic failure in adult ulcerative colitis (UC), but paediatric data are lacking.

AIM

To prospectively monitor efficacy and serum concentrations of ustekinumab given to children with UC refractory to other biologics.

METHODS

Children with anti-TNF refractory UC initiating ustekinumab intravenously at sites of the Canadian Children IBD Network prior to 12/2019 are included. The primary endpoint was steroid-free clinical remission with subcutaneous ustekinumab at 52 weeks (Paediatric Ulcerative Colitis Activity Index <10, no steroids ≥4 weeks). Ustekinumab levels were measured after week 20. Endoscopic improvement was defined as Mayo endoscopic subscore ≤1, or faecal calprotectin (FCP) <250 μg/g if not re-colonoscoped.

RESULTS

At six sites between 01/2018 and 11/2019, 25 children (median [IQR] age 14.8 years [12.3-16.2], 72% female) with UC duration 2.3 years (1.1-4.2) received intravenous ustekinumab (median dose/kg of 6.4 [5.5-7.5] mg). All patients had failed prior infliximab therapy, and 12 (48%) also vedolizumab. Five patients discontinued ustekinumab after IV induction (four undergoing colectomy). On intent to treat basis, 44% achieved the primary endpoint of steroid-free remission at week 52, including nine (69%) of 13 who previously treated with anti-TNF only vs two (17%) of 12 who previously failed also by vedolizumab (P = 0.008). Seven of 11 remitters met the criteria for endoscopic improvement. The median (IQR) trough levels (μg/mL) were greater with q4 vs q8 weekly dosing (8.7 [4.6-9.9] vs 3.8 [12.7-4.8]) P = 0.02, but greater exposure was not associated with a superior rate of clinical remission. No adverse events were associated with therapy.

CONCLUSION

Ustekinumab demonstrated efficacy in this paediatric cohort with otherwise treatment-refractory UC. Treatment failure was not due to inadequate drug exposure.

Treatment and outcome of ulcerative colitis during the first 10 years after diagnosis in a prospectively followed population-based cohort

BACKGROUND AND AIMS

There is a shortage of studies evaluating the effect of prevalent use of immunomodulators (IMMs) and biologicals on the clinical course of ulcerative colitis (UC) during 10 years. The aim of the present study is to report the use of drugs and surgery as well as mortality in a population based setting.

METHODS

Between 2005 and 2009, we identified 330 patients in all ages (3-86 years) with an incident diagnosis of UC in the County of Uppsala, Sweden. They were followed prospectively and the medical notes were retrospectively analysed with special reference to the use of drugs, surgery and mortality.

RESULTS

Median follow-up was 11.2 years (inter-quartile range 10.2-12.7). Out of the 330 patients, 298 (90.3%) could be followed for at least 10 years or until death. The cumulative exposure to different drugs was as follows: 5-ASA 96.6%, steroids 73.3%, IMMs 35.4% and biologicals 11.4%. Fourteen patients (4.6%) needed a colectomy during the observation time. Overall mortality in 10 years was 7% (23/330) whereof three patients died as a consequence of the disease or its treatment. Three patients (0.9%) were diagnosed with colonic cancer of whom two also had sclerosing cholangitis.

CONCLUSIONS

A frequent use of IMMs and biologicals during 10 years, can result in a low need for colectomy without increased mortality compared to previous reports.

Accurate Classification of Pediatric Colonic Inflammatory Bowel Disease Subtype Using a Random Forest Machine Learning Classifier

BACKGROUND

The pediatric inflammatory bowel disease (PIBD) classes algorithm was developed to bring consistency to labelling of colonic IBD, but labels are exclusively based on features atypical for ulcerative colitis (UC).

AIM

The aim of the study was to develop an algorithm and identify features that discriminate between pediatric UC and colonic Crohn disease (CD).

METHODS

Baseline clinical, endoscopic, radiologic, and histologic data, including the PIBD class features in 74 colonic IBD (56: UC, 18: colonic CD) patients were collected. The PIBD class features and additional features common to UC were used to perform initial clustering, using similarity network fusion (SNF). We trained a Random Forest (RF) classifier on the full dataset and used a leave-one-out approach to evaluate model accuracy. The top-features were used to build a new classifier, which we tested on 15 previously unused patients. We then performed clustering with SNF on the top RF features and assessed ability to discriminate between UC and colonic-CD independent of a supervised model.

RESULTS

The initial SNF clustering with 58 patients demonstrated 2 groups: group 1 (n = 39, 90% UC) and group 2 (n = 19, 68% colonic-CD). Our RF classifier correctly labelled 97% of the 58 patients based on leave-one-out cross validation and identified the 7 most important features (3 histological and 4 endoscopic) to clinically distinguish these groups. We trained a new RF classifier with the top 7 features and found 100% accuracy in a set of 15 held-out patients. Finally, post hoc clustering with these 7 features revealed 2 groups of patients: group 1 (n = 55, 98% UC) and group 2 (n = 18, 94% colonic-CD).

CONCLUSIONS

A combination of supervised and unsupervised analyses identified a short list of features, which consistently distinguish UC from colonic CD. Future directions include validation in other populations.

Predicting Therapeutic Response in Pediatric Ulcerative Colitis-A Journey Towards Precision Medicine

Ulcerative colitis (UC) is a disabling disease, characterized by chronic inflammation of the colon, with a rising prevalence worldwide in the pediatric age group. Although UC presents in children with varying severity, disease extent, and comorbidities, initial treatment is essentially uniform, consisting of 5-aminosalicylate drugs with corticosteroid induction for those with moderately to severely active disease. With the advent of anti-tumor necrosis factor (TNF) biologic therapy and several new biologics and small-molecule drugs for UC, precision medicine approaches to treatment are needed to more rapidly achieve sustained remission, restore quality of life, normalize development, and limit exposure to toxic corticosteroids in children with UC. Here, we review available data on clinical, biochemical, histopathologic, and molecular predictors of treatment response in UC. We also address known predictors and special treatment considerations in specific relevant scenarios such as very-early-onset UC, acute severe UC, ileal pouch anal anastomosis, and UC with concomitant primary sclerosing cholangitis. The review concludes with a prediction of how machine learning will integrate multimodal patient data to bring precision medicine to the bedside of children with UC in the future.

Diagnostic Delay Is Associated With Complicated Disease and Growth Impairment in Paediatric Crohn's Disease

BACKGROUND

Paediatric data on the association between diagnostic delay and inflammatory bowel disease [IBD] complications are lacking. We aimed to determine the effect of diagnostic delay on stricturing/fistulising complications, surgery, and growth impairment in a large paediatric cohort, and to identify predictors of diagnostic delay.

METHODS

We conducted a national, prospective, multicentre IBD inception cohort study including 1399 children. Diagnostic delay was defined as time from symptom onset to diagnosis >75th percentile. Multivariable proportional hazards [PH] regression was used to examine the association between diagnostic delay and stricturing/fistulising complications and surgery, and multivariable linear regression to examine the association between diagnostic delay and growth. Predictors of diagnostic delay were identified using Cox PH regression.

RESULTS

Overall (64% Crohn's disease [CD]; 36% ulcerative colitis/IBD unclassified [UC/IBD-U]; 57% male]), median time to diagnosis was 4.2 (interquartile range [IQR] 2.0-9.2) months. For the overall cohort, diagnostic delay was >9.2 months; in CD, >10.8 months and in UC/IBD-U, >6.6 months. In CD, diagnostic delay was associated with a 2.5-fold higher rate of strictures/internal fistulae (hazard ratio [HR] 2.53, 95% confidence interval [CI] 1.41-4.56). Every additional month of diagnostic delay was associated with a decrease in height-for-age z-score of 0.013 standard deviations [95% CI 0.005-0.021]. Associations persisted after adjusting for disease location and therapy. No independent association was observed between diagnostic delay and surgery in CD or UC/IBD-U. Diagnostic delay was more common in CD, particularly small bowel CD. Abdominal pain, including isolated abdominal pain in CD, was associated with diagnostic delay.

CONCLUSIONS

Diagnostic delay represents a risk factor for stricturing/internal fistulising complications and growth impairment in paediatric CD.

PODCAST

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Canadian Association of Gastroenterology Clinical Practice Guideline for the Medical Management of Pediatric Luminal Crohn's Disease

BACKGROUND & AIMS

We aim to provide guidance for medical treatment of luminal Crohn's disease in children.

METHODS

We performed a systematic search of publication databases to identify studies of medical management of pediatric Crohn's disease. Quality of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development, and Evaluation) approach. We developed statements through an iterative online platform and then finalized and voted on them.

RESULTS

The consensus includes 25 statements focused on medical treatment options. Consensus was not reached, and no recommendations were made, for 14 additional statements, largely due to lack of evidence. The group suggested corticosteroid therapies (including budesonide for mild to moderate disease). The group suggested exclusive enteral nutrition for induction therapy and biologic tumor necrosis factor antagonists for induction and maintenance therapy at diagnosis or at early stages of severe disease, and for patients failed by steroid and immunosuppressant induction therapies. The group recommended against the use of oral 5-aminosalicylate for induction or maintenance therapy in patients with moderate disease, and recommended against thiopurines for induction therapy, corticosteroids for maintenance therapy, and cannabis in any role. The group was unable to clearly define the role of concomitant immunosuppressants during initiation therapy with a biologic agent, although thiopurine combinations are not recommended for male patients. No consensus was reached on the role of aminosalicylates in treatment of patients with mild disease, antibiotics or vedolizumab for induction or maintenance therapy, or methotrexate for induction therapy. Patients in clinical remission who are receiving immunomodulators should be assessed for mucosal healing within 1 year of treatment initiation.

CONCLUSIONS

Evidence-based medical treatment of Crohn's disease in children is recommended, with thorough ongoing assessments to define treatment success.