Unfermented ß-fructan Fibers Fuel Inflammation in Select Inflammatory Bowel Disease Patients.

BACKGROUND & AIMS: Inflammatory bowel diseases (IBD) are affected by dietary factors, including nondigestible carbohydrates (fibers), which are fermented by colonic microbes. Fibers are overall beneficial, but not all fibers are alike, and some patients with IBD report intolerance to fiber consumption. Given reproducible evidence of reduced fiber-fermenting microbes in patients with IBD, we hypothesized that fibers remain intact in select patients with reduced fiber-fermenting microbes and can then bind host cell receptors, subsequently promoting gut inflammation. METHODS: Colonic biopsies cultured ex vivo and cell lines in vitro were incubated with oligofructose (5 g/L), or fermentation supernatants (24-hour anaerobic fermentation) and immune responses (cytokine secretion [enzyme-linked immunosorbent assay/meso scale discovery] and expression [quantitative polymerase chain reaction]) were assessed. Influence of microbiota in mediating host response was examined and taxonomic classification of microbiota was conducted with Kraken2 and metabolic profiling by HUMAnN2, using R software. RESULTS: Unfermented dietary ß-fructan fibers induced proinflammatory cytokines in a subset of IBD intestinal biopsies cultured ex vivo, and immune cells (including peripheral blood mononuclear cells). Results were validated in an adult IBD randomized controlled trial examining ß-fructan supplementation. The proinflammatory response to intact ß-fructan required activation of the NLRP3 and TLR2 pathways. Fermentation of ß-fructans by human gut whole microbiota cultures reduced the proinflammatory response, but only when microbes were collected from patients without IBD or patients with inactive IBD. Fiber-induced immune responses correlated with microbe functions, luminal metabolites, and dietary fiber avoidance. CONCLUSION: Although fibers are typically beneficial in individuals with normal microbial fermentative potential, some dietary fibers have detrimental effects in select patients with active IBD who lack fermentative microbe activities. The study is publicly accessible at the U.S. National Institutes of Health database (clinicaltrials.gov identification number NCT02865707).

Forecasting the Incidence and Prevalence of Inflammatory Bowel Disease: A Canadian Nationwide Analysis.

INTRODUCTION: Canada has a high burden of inflammatory bowel disease (IBD). Historical trends of IBD incidence and prevalence were analyzed to forecast the Canadian burden over the next decade. METHODS: Population-based surveillance cohorts in 8 provinces derived from health administrative data assessed the national incidence (2007-2014) and prevalence (2002-2014) of IBD. Autoregressive integrated moving average models were used to forecast incidence and prevalence, stratified by age, with 95% prediction intervals (PI), to 2035. The average annual percentage change (AAPC) with 95% confidence interval (CI) was calculated for the forecasted incidence and prevalence. RESULTS: The national incidence of IBD is estimated to be 29.9 per 100,000 (95% PI 28.3-31.5) in 2023. With a stable AAPC of 0.36% (95% CI -0.05 to 0.72), the incidence of IBD is forecasted to be 31.2 per 100,000 (95% PI 28.1-34.3) in 2035. The incidence in pediatric patients (younger than 18 years) is increasing (AAPC 1.27%; 95% CI 0.82-1.67), but it is stable in adults (AAPC 0.26%; 95% CI -0.42 to 0.82). The prevalence of IBD in Canada was 843 per 100,000 (95% PI 716-735) in 2023 and is expected to steadily climb (AAPC 2.43%; 95% CI 2.32-2.54) to 1,098 per 100,000 (95% PI 1,068-1,127) by 2035. The highest prevalence is in seniors with IBD (1,174 per 100,000 in 2023; AAPC 2.78%; 95% CI 2.75-2.81). DISCUSSION: Over the next decade, the Canadian health care systems will contend with the juxtaposition of rising incidence of pediatric IBD and a rising prevalence of overall IBD driven by the aging population.

ADALIMUMAB VERSUS INFLIXIMAB IN LUMINAL PEDIATRIC CROHN'S DISEASE: COMPARABLE OUTCOMES IN A PROSPECTIVE MULTICENTER COHORT STUDY.

BACKGROUND: This study compared real-world effectiveness between adalimumab (ADA) and infliximab (IFX) in children with Crohn's disease (CD). METHODS: Children enrolled into the prospective Canadian Children Inflammatory Bowel Disease Network (CIDsCaNN) National Inception Cohort between 2014 and 2020 who commenced ADA or IFX as first anti-tumor necrosis factor (antiTNF) agent for luminal CD were included. Multivariate logistic regression modelled the propensity of commencing ADA; propensity score matching was used to match IFX-treated children to ADA-treated children. The primary outcome at one year was steroid-free clinical remission (SFCR). Secondary outcomes at one year were I) combined SFCR and c-reactive protein (CRP) remission; II) treatment intensification; and III) antiTNF durability. Odds ratios (aOR) and hazard ratio (aHR) adjusted for concomitant immunomodulator use with 95% confidence interval (CI) are reported. RESULTS: In the propensity score matched cohort of 147 ADA-treated and 147 IFX-treated children, 92 (63%) ADA- and 87 (59%) IFX-treated children achieved SFCR at one year (aOR: 1.4, 95% CI 0.9-2.4); 75 of 140 (54%) ADA- and 85 of 144 (59%) IFX-treated children achieved combined SFCR and CRP remission (aOR: 1.0, 95% CI 0.6-1.6). ADA-treated children less frequently underwent treatment intensification (21 [14%]) compared to IFX-treated children (69 [47%]) (P<0.0001). Discontinuation of antiTNF occurred in 18 (12%) ADA-treated and 15 (10%) IFX-treated children (aHR: 1.2, 95% CI 0.6-2.2). CONCLUSION: Children with Crohn's disease achieved favourable outcomes at one year with either ADA or IFX as first antiTNF agents. Those receiving IFX did not have significantly superior outcomes compared to clinically similar children receiving ADA.

Transition Readiness in Youth with Inflammatory Bowel Disease.

OBJECTIVES: To examine readiness of adolescents and young adults (AYAs) with inflammatory bowel disease (IBD) to transition to adult care. STUDY DESIGN: A cross-sectional multicenter study evaluating transition readiness in individuals with IBD 16-19 years old prospectively recruited from 8 Canadian IBD centers using the validated ON Taking Responsibility for Adolescent to Adult Care (ON TRAC) questionnaire. Secondary aims included (1) screening for depression and anxiety using the 8-item Personal Health Questionnaire Depression Scale and The Screen for Child Anxiety Related Emotional Disorders questionnaires, respectively; (2) evaluating the association between depression and anxiety with readiness and disease activity; and (3) subjectively evaluating AYA readiness based on physician and parent assessments. RESULTS: In total, 186 participants (139 adolescent, 47 young adult) were enrolled, mean age 17.4 years (SD, 0.87). ON TRAC scores determined that 26.6% of AYAs at pediatric and 40.4% at adult centers reached the threshold of readiness. On multivariable linear regression analysis age was positively (P = .001) and disease remission negatively (P = .03) associated with ON TRAC scores. No statistically significant differences were determined across centers. A significant percentage of AYAs reported moderate-to-severe depression (21.7%) and generalized anxiety (36%); however, neither were significantly associated with ON TRAC scores. Notably, physician and parental assessment of AYA readiness correlated poorly with ON TRAC scores (⍴ = 0.11, ⍴ = 0.24, respectively). CONCLUSIONS: Assessment of transition readiness in AYAs with IBD highlighted that a large proportion do not have adequate knowledge or behavior skills needed for transition to adult care. This study infers that readiness assessment tools are essential during transition to identify deficits in knowledge and behavior skills that could be specifically targeted by the youth, caregivers, and multidisciplinary team.

Pediatric Patient and Caregiver Satisfaction With the Use of Transabdominal Bowel Ultrasound in the Assessment of Inflammatory Bowel Diseases.

OBJECTIVES: Transabdominal bowel ultrasound (TABUS) is emerging as an attractive, noninvasive tool in inflammatory bowel disease (IBD). Patient and caregiver experience with TABUS is not well described. We aimed to determine pediatric patient and caregiver satisfaction with TABUS and the impact of IBD severity, gender, age, and a history of anxiety on satisfaction. METHODS: Pediatric patients (0-18 years old) with suspected IBD prospectively underwent baseline TABUS, magnetic resonance enterography (MRE), blood work, stool studies, and endoscopy. Patients and their caregiver each completed a cross-sectional satisfaction questionnaire (5-point Likert scale) after the baseline investigations. RESULTS: There were 54 patients included (67% male). The majority were completely satisfied and strongly agree TABUS was better tolerated than other investigations, regardless of disease severity ( P > 0.05). Patients with higher Simple Endoscopic Score for Crohn Disease (SES-CD) scores felt that TABUS increased their understanding of their IBD ( P < 0.05) and disease location ( P < 0.05). Patients with Crohn disease had similar responses to those with ulcerative colitis, but more strongly agreed that TABUS was better than MRE and endoscopy ( P < 0.05). Those with anxiety did not have an increased level of worry about potential ultrasound findings ( P > 0.05). CONCLUSIONS: Pediatric patients and their caregivers were highly satisfied with TABUS, preferring it to other modalities. It did not lead to increased worry, and was particularly important in those with severe IBD. These findings support wider implementation of this well tolerated and preferred monitoring tool in pediatrics.

Canadian Association of Gastroenterology Clinical Practice Guideline for Immunizations in Patients With Inflammatory Bowel Disease (IBD)-Part 2: Inactivated Vaccines.

BACKGROUND AND AIMS: The effectiveness and safety of vaccinations can be altered by immunosuppressive therapies, and perhaps by inflammatory bowel disease (IBD) itself. These recommendations developed by the Canadian Association of Gastroenterology and endorsed by the American Gastroenterological Association, aim to provide guidance on immunizations in adult and pediatric patients with IBD. This publication focused on inactivated vaccines. METHODS: Systematic reviews evaluating the efficacy, effectiveness, and safety of vaccines in patients with IBD, other immune-mediated inflammatory diseases, and the general population were performed. Critical outcomes included mortality, vaccine-preventable diseases, and serious adverse events. Immunogenicity was considered a surrogate outcome for vaccine efficacy. Certainty of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development, and Evaluation) approach. Key questions were developed through an iterative online platform, and voted on by a multidisciplinary group. Recommendations were formulated using the Evidence-to-Decision framework. Strong recommendation means that most patients should receive the recommended course of action, whereas a conditional recommendation means that different choices will be appropriate for different patients. RESULTS: Consensus was reached on 15 of 20 questions. Recommendations address the following vaccines: Haemophilus influenzae type b, recombinant zoster, hepatitis B, influenza, pneumococcus, meningococcus, tetanus-diphtheria-pertussis, and human papillomavirus. Most of the recommendations for patients with IBD are congruent with the current Centers for Disease Control and Prevention and Canada's National Advisory Committee on Immunization recommendations for the general population, with the following exceptions. In patients with IBD, the panel suggested Haemophilus influenzae type b vaccine for patients older than 5 years of age, recombinant zoster vaccine for adults younger than 50 year of age, and hepatitis B vaccine for adults without a risk factor. Consensus was not reached, and recommendations were not made for 5 statements, due largely to lack of evidence, including double-dose hepatitis B vaccine, timing of influenza immunization in patients on biologics, pneumococcal and meningococcal vaccines in adult patients without risk factors, and human papillomavirus vaccine in patients aged 27-45 years. CONCLUSIONS: Patients with IBD may be at increased risk of some vaccine-preventable diseases. Therefore, maintaining appropriate vaccination status in these patients is critical to optimize patient outcomes. In general, IBD is not a contraindication to the use of inactivated vaccines, but immunosuppressive therapy may reduce vaccine responses.

Canadian Association of Gastroenterology Clinical Practice Guideline for Immunizations in Patients With Inflammatory Bowel Disease (IBD)-Part 1: Live Vaccines.

BACKGROUND & AIMS: Patients with inflammatory bowel disease (IBD) may be at increased risk of some vaccine-preventable diseases. The effectiveness and safety of vaccinations may be altered by immunosuppressive therapies or IBD itself. These recommendations developed by the Canadian Association of Gastroenterology and endorsed by the American Gastroenterological Association, aim to provide guidance on immunizations in adult and pediatric patients with IBD. This publication focused on live vaccines. METHODS: Systematic reviews evaluating the efficacy, effectiveness, and safety of vaccines in patients with IBD, other immune-mediated inflammatory diseases, and the general population were performed. Critical outcomes included mortality, vaccine-preventable diseases, and serious adverse events. Immunogenicity was considered a surrogate outcome for vaccine efficacy. Certainty of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development, and Evaluation) approach. Key questions were developed through an iterative process and voted on by a multidisciplinary panel. Recommendations were formulated using the Evidence-to-Decision framework. Strong recommendation means that most patients should receive the recommended course of action, whereas a conditional recommendation means that different choices will be appropriate for different patients. RESULTS: Three good practice statements included reviewing a patient's vaccination status at diagnosis and at regular intervals, giving appropriate vaccinations as soon as possible, and not delaying urgently needed immunosuppressive therapy to provide vaccinations. There are 4 recommendations on the use of live vaccines. Measles, mumps, rubella vaccine is recommended for both adult and pediatric patients with IBD not on immunosuppressive therapy, but not for those using immunosuppressive medications (conditional). Varicella vaccine is recommended for pediatric patients with IBD not on immunosuppressive therapy, but not for those using immunosuppressive medications (conditional). For adults, recommendations are conditionally in favor of varicella vaccine for those not on immunosuppressive therapy, and against for those on therapy. No recommendation was made regarding the use of live vaccines in infants born to mothers using biologics because the desirable and undesirable effects were closely balanced and the evidence was insufficient. CONCLUSIONS: Maintaining appropriate vaccination status in patients with IBD is critical to optimize patient outcomes. In general, live vaccines are recommended in patients not on immunosuppressive therapy, but not for those using immunosuppressive medications. Additional studies are needed to evaluate the safety and efficacy of live vaccines in patients on immunosuppressive therapy.

Hospitalization With Clostridioides difficile in Pediatric Inflammatory Bowel Disease: a Population-Based Study.

OBJECTIVES: Several studies have demonstrated higher rates of Clostridioides difficile infection (CDI) in adults with inflammatory bowel disease (IBD). We conducted a population-based study comparing the risk of hospitalization with CDI in children with and without IBD. METHODS: Using health administrative data and validated algorithms, we identified all children (<16 years) diagnosed with IBD in 5 Canadian provinces, then age and sex matched to 5 children without IBD. Province-specific 5-year incidence rates of hospitalization with CDI were pooled and generalized linear mixed-effects models were used to estimate the crude incidence rate ratio (IRR) comparing (1) children with and without IBD and (2) children with Crohn disease and ulcerative colitis. Hazard ratios (HR) from Cox proportional hazards models adjusting for age, sex, rural/urban household, and income were pooled using fixed-effects models. RESULTS: The incidence rate of CDI identified during hospitalization was 49.06 [95% confidence interval (CI), 39.40-61.08] per 10,000 person-years (PY) in 3593 children with IBD compared to 0.39 (95% CI, 0.13-1.21) per 10,000 PY in 16,284 children without IBD (crude IRR, 133.4, 95% CI, 42.1-422.7; adjusted HR, 68.2, 95% CI, 24.4-190.4). CDI was identified less often in children with Crohn disease than ulcerative colitis (crude IRR, 0.51, 95% CI, 0.32-0.82; adjusted HR, 0.69, 95% CI, 0.46-1.05). CONCLUSIONS: Children with IBD have a markedly higher incidence of CDI identified during a hospitalization relative to children without IBD. Consequently, symptomatic children with IBD who are hospitalized should be screened for CDI.

FODMAP intake in children with coeliac disease influences diet quality and health-related quality of life and has no impact on gastrointestinal symptoms.

Children with coeliac disease (CD) following the gluten-free diet may experience ongoing gastrointestinal symptoms despite strict adherence. The study objective was to evaluate the association between foods high in fermentable oligo/di/monosaccharides, and polyols (FODMAP) and gastrointestinal symptoms, and the potential implications to diet quality and health-related quality of life in CD children. Dietary intake was studied in age-sex matched children 5-18 years (CD, n = 46; non-coeliac mild chronic gastrointestinal complaints [GIC], n = 46; healthy controls [HC], n = 46). CD children consumed fewer foods high in FODMAPs compared to GIC and HC (p < .0001). FODMAP intake was not related to gastrointestinal symptoms in CD children (p > 0.05) but was positively associated with child health-related quality of life (p < 0.05). FODMAP intake from fruits and vegetables was positively associated with diet adequacy and total diet quality in CD children (p < 0.05). FODMAP intake may influence diet quality and health-related quality of life but has no impact on gastrointestinal symptoms in CD children.

Gut Microenvironment and Bacterial Invasion in Paediatric Inflammatory Bowel Diseases.

OBJECTIVES: Host-microbial relationship is disrupted in inflammatory bowel diseases (IBD). We hypothesized that altered gut luminal microenvironment can impact microbial virulence in IBD, leading to disruption of homeostasis and disease. We investigated the relationship between gut microenvironment and microbial virulence. METHODS: Intestinal aspirates were collected from 10 non-IBD controls, 9 Crohn disease, and 10 ulcerative colitis paediatric patients during endoscopy. In vitro invasion of bacteria isolated from the duodenum and terminal ileum (TI) was quantified using gentamicin protection assays. Intestinal epithelial cells were infected in vitro by known Escherichia coli strains with patient intestinal aspirates added. Nuclear magnetic resonance spectroscopy (NMR) analysis was conducted on intestinal aspirates to identify metabolites associated with invasion; these metabolites were then introduced to the infection model. RESULTS: There was no difference in in vitro invasion of bacteria obtained from intestinal aspirates of non-IBD and IBD patients. Incubation of laboratory E coli strains with TI aspirates from IBD patients increased their invasion into epithelial cells in vitro. NMR analysis revealed intestinal metabolites that correlated with bacterial invasion; succinate present in the intestinal aspirates correlated positively, whereas acetate and formate related negatively with invasion. Addition of exogenous succinate increased invasion of E coli in vitro. CONCLUSIONS: Alterations in the gut microenvironment in IBD can affect bacterial invasion. Succinate is associated with increased bacterial invasion and can alter bacterial virulence in IBD. This highlights the interaction between specific metabolites and bacteria that could be instrumental in propagating or suppressing inflammation in paediatric IBD patients.

Discontinuation of Immunosuppressive Medications in Children With Inflammatory Bowel Disease on Combination Therapy.

We determined the frequency and factors associated with the first clinical relapse after immunomodulator (IM) withdrawal in a cohort of children with inflammatory bowel disease on combination therapy. A total of 105 patients (89 with Crohn disease [CD]) in clinical remission were included (91 [86.7%] were on infliximab, 53 [50.5%] with methotrexate, and 52 on azathioprine). The median duration of combination therapy was 2.1 years (interquartile range [IQR] 1.3-2.8). Only 11 (10.5%) patients experienced a clinical relapse over a median duration of follow-up of 12.0 months (IQR 5.0-19.0) after IM discontinuation. The median baseline pediatric CD activity index in those with CD who relapsed after IM discontinuation was 47.5 (IQR: 35.0-55.0) versus those who did not relapse (median 35.0, IQR: 20.0-52.5; P = 0.04). In the patients who did not relapse, the median IFX trough level at IM discontinuation was 6.2 and 3.8 µg/mL in those who relapsed.

Outcomes Following Pouch Formation in Paediatric Ulcerative Colitis: A Study From the Porto Group of ESPGHAN.

INTRODUCTION: Contemporary pediatric data on pouch outcomes are sparse, especially in the era of laparoscopic surgeries. We aimed to assess outcomes and predictors in children with ulcerative colitis/inflammatory bowel disease (IBD)-unclassified who underwent colectomy and ileal pouch-anal anastomosis. METHODS: This was a multicenter retrospective cohort study from 17 IBD centers affiliated with the pediatric IBD Porto group of ESPGHAN. An electronic REDcap system was used to collate baseline characteristics, demographic, clinical, management and surgical data, short- and long-term outcomes, and to identify potential predictors of pouch outcome. RESULTS: Of the 129 patients included, 86 (67%) developed pouchitis during follow-up of median 40 months (interquartile range 26-72), of whom 33 (26%) with chronic pouchitis. Patients operated on by surgeons performing <10 pouch surgeries/year had a higher rate of chronic pouchitis (11/27 [41%] vs 8/54 [15%], P = 0.013) on both univariable and multivariable analyses and also associated with time to pouchitis (P = 0.018) and chronic pouchitis (P = 0.020). At last follow-up, overall pouch performance was rated good/excellent in 86 (74%) patients. Time from colectomy to pouch formation was not associated with pouch outcomes. Despite higher rate of nonsevere surgical complications among children undergoing colectomy at <10 years of age (7/16 [44%] vs 10/92 [11%], P = 0.003), functional outcome and pouchitis rate did not differ. CONCLUSIONS: Pouchitis rate in children with ulcerative colitis/IBD unclassified is high. Surgeon experience is the major modifiable risk factor for pouch outcome. Our analyses suggest that pouch surgery can also be performed successfully in young children.

Adherence to the Gluten-free Diet and Health-related Quality of Life in an Ethnically Diverse Pediatric Population With Celiac Disease.

OBJECTIVES: Celiac disease (CD) is an autoimmune disease that requires lifelong adherence to a gluten-free diet (GFD). Adherence to the GFD in childhood may be poor and adversely influence health-related quality of life (HRQOL). The study purpose was to determine sociodemographic and socioeconomic factors influencing adherence to the GFD and HRQOL in a multiethnic cohort of youth with CD. METHODS: A multisite (Edmonton, Hamilton, Toronto) study examining child-parent HRQOL in youth with CD (n = 243) and/or mild gastrointestinal complaints (GI-CON; n = 148) was conducted. Sociodemographic (age, child-parental age/education/ethnicity/place of birth), anthropometric (weight, height, body mass index), disease (diagnosis, age at diagnosis, duration, Marsh score, serology), household characteristics (income, family size, region, number of children/total household size), HRQOL (Peds TM/KINDL and Celiac Disease DUX), GI Complaints (PedsQL: Gastrointestinal Symptom Scale) and gluten intake were measured. RESULTS: Younger age (<10 years), non-Caucasian ethnicity (parent/child), and presence of GI symptoms were associated with the highest rates of adherence to the GFD in CD children (P < 0.05). CD children (parent/child) had higher HRQOL (average, composite domains) than GI-CON (P < 0.05), but CD children were comparable to healthy children. Lack of GI symptoms, non-Caucasian ethnicity and age (<10 years) were associated with increased HRQOL in composite/average domains for CD (P < 0.05). CONCLUSIONS: Child-parent perceptions of HRQOL in a multiethnic population with CD are comparable to healthy reference populations, but significantly higher than in parent/child GI-CON. Adherence to the GFD in ethnically diverse youth with CD was related to GI symptoms, age of the child, and ethnicity of the parent-child.

Global Variation in Use of Enteral Nutrition for Pediatric Crohn Disease.

OBJECTIVES: Exclusive enteral nutrition (EEN) is an effective induction treatment for pediatric Crohn disease. Given the center-based variation in use and diversity in practice, we constructed a survey aimed at sharing experience and strategies in administering EEN, stimulating further research, and optimizing therapy. METHODS: This survey was constructed after consultation with experts and designed to address key knowledge gaps. The survey was disseminated through the Pediatric IBD Porto Group of ESPGHAN, Canadian Children IBD Network, selective experts, and was sent twice through the Pediatric Gastrointestinal-Bulletin Board (PEDGI-BB). Data were collected into REDCap and analyzed using descriptive statistics. RESULTS: In total, 146 participants from 26 countries completed the survey. Sixty-five percentage of participants were general, non-inflammatory bowel diseases (IBD)-focused pediatric gastroenterologists, 21% were IBD-focused, and 10% were dietitians. The most common indications (∼90% use) were for ileocecal and ileocolonic disease (Paris L1 and L3). The most common duration was 8 weeks and 66% preferred oral to nasogastric administration. Most (63%) did not allow any additional intake and 69% instructed patients to continue partial enteral nutrition (EN) after completing treatment. Dietitians were identified as essential to EEN success while the primary challenges of EEN programs were adherence and lack of support. Regional and professional practice differences were observed in EEN indication, age, exclusivity, program structure/support, and cost coverage. CONCLUSIONS: We found significant variation in practice and use of EEN with several regional and professional differences. Global variation offers opportunities for research and improving care. This survey establishes a framework and provides resources for collaboration and information sharing.

Trends in Epidemiology of Pediatric Inflammatory Bowel Disease in Canada: Distributed Network Analysis of Multiple Population-Based Provincial Health Administrative Databases.

OBJECTIVES: The incidence of pediatric-onset inflammatory bowel disease (IBD) is increasing worldwide. We used population-based health administrative data to determine national Canadian IBD incidence, prevalence, and trends over time of childhood-onset IBD. METHODS: We identified children <16 years (y) diagnosed with IBD 1999-2010 from health administrative data in five provinces (Alberta, Manitoba, Nova Scotia, Ontario, Quebec), comprising 79.2% of the Canadian population. Standardized incidence and prevalence were calculated per 100,000 children. Annual percentage change (APC) in incidence and prevalence were determined using Poisson regression analysis. Provincial estimates were meta-analyzed using random-effects models to produce national estimates. RESULTS: 5,214 incident cases were diagnosed during the study period (3,462 Crohn's disease, 1,382 ulcerative colitis, 279 type unclassifiable). The incidence in Canada was 9.68 (95% CI 9.11 to 10.25) per 100,000 children. Incidence was similar amongst most provinces, but higher in Nova Scotia. APC in incidence did not significantly change over the study period in the overall cohort (+2.06%, 95% CI -0.64% to +4.76%). However, incidence significantly increased in children aged 0-5y (+7.19%, 95% +2.82% to +11.56%). Prevalence at the end of the study period in Canada was 38.25 (95% CI 35.78 to 40.73) per 100,000 children. Prevalence increased significantly over time, APC +4.56% (95% CI +3.71% to +5.42%). CONCLUSIONS: Canada has amongst the highest incidence of childhood-onset IBD in the world. Prevalence significantly increased over time. Incidence was not statistically changed with the exception of a rapid increase in incidence in the youngest group of children.

Corrigendum: Rural and Urban Residence During Early Life Is Associated with a Lower Risk of Inflammatory Bowel Disease: A Population-Based Inception and Birth Cohort Study.

This corrects the article DOI: 10.1038/ajg.2017.208.

Rural and Urban Residence During Early Life is Associated with Risk of Inflammatory Bowel Disease: A Population-Based Inception and Birth Cohort Study

OBJECTIVES: To determine the association between inflammatory bowel disease (IBD) and rural/urban household at the time of diagnosis, or within the first 5 years (y) of life. METHODS: Population-based cohorts of residents of four Canadian provinces were created using health administrative data. Rural/urban status was derived from postal codes based on population density and distance to metropolitan areas. Validated algorithms identified all incident IBD cases from administrative data (Alberta: 1999-2008, Manitoba and Ontario: 1999-2010, and Nova Scotia: 2000-2008). We determined sex-standardized incidence (per 100,000 patient-years) and incident rate ratios (IRR) using Poisson regression. A birth cohort was created of children in whom full administrative data were available from birth (Alberta 1996-2010, Manitoba 1988-2010, and Ontario 1991-2010). IRR was calculated for residents who lived continuously in rural/urban households during each of the first 5 years of life. RESULTS: There were 6,662 rural residents and 38,905 urban residents with IBD. Incidence of IBD per 100,000 was 33.16 (95% CI 27.24-39.08) in urban residents, and 30.72 (95% CI 23.81-37.64) in rural residents (IRR 0.90, 95% CI 0.81-0.99). The protective association was strongest in children <10 years (IRR 0.58, 95% CI 0.43-0.73) and 10-17.9 years (IRR 0.72, 95% CI 0.64-0.81). In the birth cohort, comprising 331 rural and 2,302 urban residents, rurality in the first 1-5 years of life was associated with lower risk of IBD (IRR 0.75-0.78). CONCLUSIONS: People living in rural households had lower risk of developing IBD. This association is strongest in young children and adolescents, and in children exposed to the rural environment early in life.

Capillary Flow Rates in the Duodenum of Pediatric Ulcerative Colitis Patients Are Increased and Unrelated to Inflammation.

BACKGROUND AND AIM: Inflammatory bowel diseases (IBD), including Crohn disease (CD) and ulcerative colitis (UC), are chronic pediatric disorders. Changes in vasculature are described in IBD, but these could be secondary to inflammation and the role in pathogenesis is poorly understood. Assessing circulatory changes in typically unaffected sites in IBD (eg, duodenum), when inflammation is absent, can identify vascular changes associated with pathogenesis. The aim of the study is to measure capillary flow rates in duodenal mucosa using probe-based confocal laser endomicroscopy (pCLE) during endoscopy in children with IBD. METHODS: Images of villi with visible blood vessels obtained using pCLE were captured as video sequences. Capillary flow rate (mm/s) was calculated by dividing the distance travelled by blood cells by the duration of the sequence. Flow rates were correlated with various clinical parameters. RESULTS: Forty-five patients (22 non-IBD, 14 CD, 9 UC) were included in the study. Duodenal capillary flow rates were significantly higher in UC patients (0.75 ±â€Š0.07 mm/s) as compared to non-IBD (0.57 ±â€Š0.03) and CD (0.65 ±â€Š0.04). There was no correlation between serum hemoglobin and albumin, disease activity indices, serum inflammatory markers, and capillary flow rates in patients. CONCLUSIONS: This pilot study shows, for the first time, increased capillary blood flow in the duodenum of UC patients that was unrelated to inflammatory markers or disease activity. Thus, early vascular changes can be assessed using pCLE during endoscopy.

Increased Epithelial Gap Density in the Noninflamed Duodenum of Children With Inflammatory Bowel Diseases.

OBJECTIVES: Inflammatory bowel diseases (IBD) present commonly in childhood, with unknown etiology, but an important role for the epithelial lining is suggested. Epithelial cell extrusion, measured by counting gaps between epithelial cells, is higher in adult patients with Crohn disease (CD) than in controls. Our objectives were to compare epithelial gaps in the duodenum of IBD and non-IBD pediatric patients, to study the correlation between epithelial gaps, inflammation, and disease activity, and identify potential mechanisms. METHODS: Epithelial gap density of the duodenum was evaluated using probe-based confocal laser endomicroscopy in 26 pediatric patients with IBD (16 CD, 10 ulcerative colitis [UC]) and 17 non-IBD controls during endoscopy. Epithelial gaps were correlated with serum inflammatory markers, disease activity indices, and intraepithelial lymphocytes. A panel of 10 inflammatory cytokines and expression of TNFAIP3 (A20; inhibits NF-κß-induced inflammation) were analyzed in duodenal and ileal biopsies. RESULTS: Confocal imaging showed significantly higher epithelial gap density in patients with IBD, including UC. Interleukin (IL)-2 and IL-8 were higher in duodenal but not ileal biopsies of patients with UC. No significant correlation was present between C-reactive protein, erythrocyte sedimentation rate, disease activity indices, and epithelial gaps in patients with UC. In patients with CD, C-reactive protein positively correlated with epithelial gaps. A20 expression in the duodenum was unchanged among non-IBD and IBD cases. CONCLUSIONS: Duodenal epithelial gaps are increased in pediatric patients with IBD (including UC) but are unrelated to inflammation. This suggests that altered epithelial barrier is an important systemic feature of pediatric IBD and is not only secondary to inflammation.

Linezolid for treatment of chronic extensively drug-resistant tuberculosis.

BACKGROUND: Linezolid has antimycobacterial activity in vitro and is increasingly used for patients with highly drug-resistant tuberculosis. METHODS: We enrolled 41 patients who had sputum-culture-positive extensively drug-resistant (XDR) tuberculosis and who had not had a response to any available chemotherapeutic option during the previous 6 months. Patients were randomly assigned to linezolid therapy that started immediately or after 2 months, at a dose of 600 mg per day, without a change in their background regimen. The primary end point was the time to sputum-culture conversion on solid medium, with data censored 4 months after study entry. After confirmed sputum-smear conversion or 4 months (whichever came first), patients underwent a second randomization to continued linezolid therapy at a dose of 600 mg per day or 300 mg per day for at least an additional 18 months, with careful toxicity monitoring. RESULTS: By 4 months, 15 of the 19 patients (79%) in the immediate-start group and 7 of the 20 (35%) in the delayed-start group had culture conversion (P=0.001). Most patients (34 of 39 [87%]) had a negative sputum culture within 6 months after linezolid had been added to their drug regimen. Of the 38 patients with exposure to linezolid, 31 (82%) had clinically significant adverse events that were possibly or probably related to linezolid, including 3 patients who discontinued therapy. Patients who received 300 mg per day after the second randomization had fewer adverse events than those who continued taking 600 mg per day. Thirteen patients completed therapy and have not had a relapse. Four cases of acquired resistance to linezolid have been observed. CONCLUSIONS: Linezolid is effective at achieving culture conversion among patients with treatment-refractory XDR pulmonary tuberculosis, but patients must be monitored carefully for adverse events. (Funded by the National Institute of Allergy and Infectious Diseases and the Ministry of Health and Welfare, South Korea; ClinicalTrials.gov number, NCT00727844.).