Incidence of stricturing and penetrating complications of Crohn's disease diagnosed in pediatric patients

A Treat-to-Target Strategy Guided by Pan-Enteric Evaluation in Children With Crohn's Disease Improves Outcomes at 2 Years

BACKGROUND AND AIMS

It is uncertain whether a treat-to-target approach could be an effective strategy for improving outcomes in children with Crohn's disease (CD). Previously, we reported mucosal healing (MH) and deep remission rates throughout the intestinal tract by performing 3 pan-enteric capsule assessments and using a treat-to-target strategy over 52 weeks in children with CD. This report describes the outcomes of this approach at 104 weeks.

METHODS

Children with known CD who completed the 52-week protocol repeated pan-enteric capsule endoscopy (PCE) at 104 weeks. Results at weeks 52 and 104 were compared, and long-term outcomes between patients, with and without MH, were calculated using an intention-to-treat analysis of clinical relapse, need for steroids, treatment escalation, hospitalization, and surgery.

RESULTS

Of the previous study cohort of 48 patients, 46 (96%) were available for this extension study (28 [61%] of 46 with MH and 18 [39%] of 46 without MH at 52 weeks). When evaluated at 104 weeks, MH was maintained in 93% of patients with MH at 52 weeks. In the intention-to-treat analysis, complete MH at 52 weeks was associated with reduced risk of steroid use (log-rank P < .0001), treatment escalation (log-rank P < .0001), hospitalization (log-rank P < .0001), and clinical relapse (log-rank P < .0001).

CONCLUSIONS

When a PCE-based, treat-to-target strategy is employed, MH is sustainable (93%) over a 1-year period and is correlated with improved patient outcomes, including reduced need for steroids, treatment escalation, hospitalization, and clinical relapses at 104 weeks.ClinicalTrials.gov number: NCT03161886.

Challenges in IBD Research 2024: Pragmatic Clinical Research

Pragmatic clinical research is 1 of the 5 focus areas of the Challenges in IBD Research 2024, a multidisciplinary effort by scientists, clinicians, patients, and funders to identify priorities for patient-centric research. This summary provides a comprehensive overview of current gaps in inflammatory bowel disease (IBD) clinical research and actionable approaches to address them. This review is focused on identifying research that is needed to achieve the best outcomes for patients in clinical practice. Research gaps include understanding the needs of understudied patient groups and addressing barriers to care so all patients receive optimal care, validating and using biomarkers to enable early diagnosis and result in better outcomes for adults and children with IBD, and determining the optimal sequencing of treatments (medical, surgical, adjunct) in children and adults. Inclusive pragmatic research is needed to address these gaps and lead to improvements in patient care and outcomes for all populations of patients with IBD.

Early Anti-Tumor-Necrosis-Factor Therapy for Crohn's Disease-Related Abdominal Abscesses and Phlegmon in Children

BACKGROUND

Internally penetrating Crohn's Disease complications, including abscesses and phlegmon, represent a high-risk Crohn's Disease phenotype. Anti-tumor-necrosis-factor-α (Anti-TNF) therapies are effective in treating penetrating Crohn's Disease and early initiation has shown unique benefits. However, timing of anti-TNF initiation in the setting of internally penetrating Crohn's Disease complications is typically heterogenous due to concern over precipitating serious infections. Recent studies demonstrate such an association may not exist.

AIMS

We aimed to describe the multidisciplinary management of pediatric patients with internally penetrating Crohn's Disease complications, focusing on the utilization and timing of anti-TNF therapy relative to complication resolution and adverse events.

METHODS

We performed a single-center retrospective cohort study of pediatric patients with internally penetrating Crohn's Disease complications from 2007 to 2021. The safety and effectiveness of anti-TNF therapy initiation prior to complication resolution was assessed by comparing rates of infectious and Crohn's Disease-related adverse events between those who received anti-TNF therapy prior to complication resolution, versus those who did not.

RESULTS

Twenty-one patients with internally penetrating Crohn's Disease complications were identified. 7/21 received anti-TNF therapy prior to complication resolution. Infectious adverse events within 90 days of complication occurred in 0/7 patients initiating anti-TNF therapy prior to complication resolution and 10/14 patients who did not (p = 0.004). Crohn's Disease-related surgeries and hospitalizations within 1 year of complication occurred in 12/20 patients, with similar frequency between groups.

CONCLUSIONS

Initiating anti-TNF therapy prior to internally penetrating Crohn's Disease complication resolution may be a safe and effective strategy to improve clinical outcomes.

Predictors of Perianal Fistula Healing in Children With Newly Diagnosed Crohn Disease

OBJECTIVES

Perianal fistulas are among the most severe complications of Crohn disease, but limited data regarding their outcomes are available in children. Our objective was to determine predictors of perianal fistula healing among pediatric patients newly diagnosed with Crohn disease.

METHODS

This single-center retrospective study followed patients with perianal fistulas at Crohn disease diagnosis until fistula healing. Time to healing was analyzed using Cox proportional hazard regression models considering relevant covariates including patient demographics, disease characteristics, medical therapies [no anti-tumor necrosis factor (TNF)α therapy, anti-TNFα therapy ±therapeutic drug monitoring], and perianal surgical procedures including fistulotomy, fistulectomy, removal of perianal lesions, seton placement, and incision and drainage.

RESULTS

Of 485 patients identified, 107 (22%) had a perianal fistula at Crohn disease diagnosis. Multivariate analysis identified that perianal fistulotomy, fistulectomy, and lesion removal [hazard ratio (HR) 0.46; P = 0.028], non-White race (HR 0.30, P < 0.01), and male sex (HR 0.42; P = 0.02) were associated with delayed fistula healing. Faster fistula healing was associated with treatment with anti-TNFα with therapeutic drug monitoring (HR 1.78, P = 0.009). There were no other differences in healing by treatment.

CONCLUSIONS

Fistulotomy, fistulectomy, and perianal lesion removal as well as non-White race were associated with delayed fistula healing. Anti-TNFα therapy was associated with faster fistula healing when combined with therapeutic drug monitoring, compared to all other medical treatment groups, including anti-TNFα therapy without therapeutic drug monitoring.

Quantification of Mucosal Activity from Colonoscopy Reports via the Simplified Endoscopic Mucosal Assessment for Crohn's Disease

BACKGROUND

Endoscopic mucosal healing is the gold standard for evaluating Crohn's disease (CD) treatment efficacy. Standard endoscopic indices are not routinely used in clinical practice, limiting the quality of retrospective research. A method for retrospectively quantifying mucosal activity from documentation is needed. We evaluated the simplified endoscopic mucosal assessment for CD (SEMA-CD) to determine if it can accurately quantify mucosal severity recorded in colonoscopy reports.

METHODS

Pediatric patients with CD underwent colonoscopy that was video recorded and evaluated via Simple Endoscopic Score for CD (SES-CD) and SEMA-CD by central readers. Corresponding colonoscopy reports were de-identified. Central readers blinded to clinical history and video scoring were randomly assigned colonoscopy reports with and without images. The SEMA-CD was scored for each report. Correlation with video SES-CD and SEMA-CD were assessed with Spearman rho, inter-rater, and intrarater reliability with kappa statistics.

RESULTS

Fifty-seven colonoscopy reports were read a total of 347 times. The simplified endoscopic mucosal assessment for CD without images correlated with both SES-CD and SEMA-CD from videos (rho = 0.82, P < .0001 for each). The addition of images provided similar correlation. Inter-rater and intrarater reliability were 0.93 and 0.92, respectively.

CONCLUSIONS

The SEMA-CD applied to retrospective evaluation of colonoscopy reports accurately and reproducibly correlates with SES-CD and SEMA-CD of colonoscopy videos. The SEMA-CD for evaluating colonoscopy reports will enable quantifying mucosal healing in retrospective research. Having objective outcome data will enable higher-quality research to be conducted across multicenter collaboratives and in clinical registries. External validation is needed.

A Microbial Signature for Paediatric Perianal Crohn's Disease

BACKGROUND AND AIMS

Perianal fistulising disease can affect up to 25% of patients with Crohn's disease [CD] and lead to significant morbidity. Although the role of the gut microbiota in inflammatory bowel disease [IBD] has been increasingly recognised, its role in fistula development has scarcely been studied. Here, we aimed to define the microbial signature associated with perianal fistulising CD in children.

METHODS

A prospective observational study including children age 6-18 years with a diagnosis of perianal fistulising CD was conducted. Stool samples and rectal and perianal fistula swabs were collected. Stool samples and rectal swabs from children with CD without perianal disease and healthy children were included as comparison. Whole shotgun metagenomic sequencing was performed.

RESULTS

A total of 31 children [mean age 15.5 ± 3.5 years] with perianal CD were prospectively enrolled. The fistula-associated microbiome showed an increase in alpha diversity and alteration in the abundance of several taxa compared with the rectal- and faecal-associated microbiome with key taxa belonging to the Proteobacteria phylum. Genes conferring resistance to the clinically used antibiotic regimen ciprofloxacin and metronidazole were found in the three sample types. In comparison with children without the perianal phenotype [N = 36] and healthy controls [N = 41], the mucosally-associated microbiome of children with perianal CD harboured a reduced butyrogenic potential. Linear discriminant analysis identified key taxa distinguishing the rectal mucosally-associated microbiome of children with perianal CD from children without this phenotype.

CONCLUSIONS

The microbial community within CD-related anorectal fistula is compositionally and functionally unique. Taken together, these findings emphasise the need to better understand the ecosystem of the fistula milieu to guide development of novel microbiome-based strategies in this CD phenotype.

Perianal Crohn Disease Is More Common in Children and Is Associated With Complicated Disease Course Despite Higher Utilization of Biologics: A Population-based Study From The epidemiology group of the Israeli IBD Research Nucleus (epiIIRN)

BACKGROUND AND OBJECTIVES

Both perianal and pediatric-onset Crohn disease (CD) disease are associated with complicated disease course and higher drug utilization. we aimed to explore the differences between pediatric and adult-onset perianal CD and their disease course.

METHODS

We included all patients with newly diagnosed CD from 2005 to 2019 at two Israeli Health Maintenance Organizations, covering 78% of the population. A combination of ICD-9 codes, radiology and procedures was used to define fistulizing perianal CD (PCD) and its severity according to the association with simple and complex perianal disease.

RESULTS

A total of 12,905 patients were included (2186 [17%] pediatric-onset, 10,719 [83%] adults), with a median follow-up of 7.8 years. PCD was diagnosed in 1530 (12%) patients, with higher incidence in children (308 [14%] children vs 1222 adults [11%]; P  < 0.001). Children had higher incidence of severe PCD (141/308 [47%] vs 433/1222 [35%]; P < 0.001). At 5 years, children with PCD were more likely than adults to be treated with biologics (212 [69%] vs 515 [42%]; odds ratio [OR] 2.6 [95% confidence interval (CI) 1.6-4.0]; P < 0.001) and immunomodulators (238 [74%] vs 643 [53%]; OR 2.8 [95% CI 2.1-3.6]; P < 0.001). PCD in children was still associated with poorer disease outcomes as shown for surgeries (36 [12%] vs 93 [8%]; P = 0.02) and steroid-dependency (52 [17%] vs 156 [13%]; P < 0.001). Multivariable modeling indicated that the severity of PCD is a stronger predictor of disease course than age.

CONCLUSION

PCD is more common in pediatric-onset CD and is associated with higher drug utilization and worse disease outcomes, in large due to higher rate of severe PCD in children.

Surgical Planning in Penetrating Abdominal Crohn's Disease

Crohn's disease (CD) is increasing globally, and the disease location and behavior are changing toward more colonic as well as inflammatory behavior. Surgery was previously mainly performed due to ileal/ileocaecal location and stricturing behavior, why many anticipate the surgical load to decrease. There are, however, the same time data showing an increasing complexity among patients at the time of surgery with an increasing number of patients with the abdominal perforating disease, induced by the disease itself, at the time of surgery and thus a more complex surgery as well as the post-operative outcome. The other major cause of abdominal penetrating CD is secondary to surgical complications, e.g., anastomotic dehiscence or inadvertent enterotomies. To improve the care for patients with penetrating abdominal CD in general, and in the peri-operative phase in particular, the use of multidisciplinary team discussions is essential. In this study, we will try to give an overview of penetrating abdominal CD today and how this situation may be handled. Proper surgical planning will decrease the risk of surgically induced penetrating disease and improve the outcome when penetrating disease is already established. It is important to evaluate patients prior to surgery and optimize them with enteral nutrition (or parenteral if enteral nutrition is ineffective) and treat abdominal sepsis with drainage and antibiotics.

What Are the Different Phenotypes of Inflammatory Bowel Disease in Asia?

The burden of inflammatory bowel disease (IBD) in Asia has been increasing over the past decades. Although patients with IBD show heterogenous phenotypes depending on the individual characteristics, no significant differences have been established in the IBD phenotypes of Western and Asian populations. However, despite the much lower incidence of IBD in Asia than in Western countries, the incidence has been rapidly increasing in Asia while remaining stable in Western countries. The incidence of ulcerative colitis (UC) showed an earlier and a more marked increase than the incidence of Crohn disease (CD), but the UC-to-CD ratio has recently decreased because of a relative increase in the incidence of CD in Asia. While CD shows a significant male predominance, UC only shows a slight male predominance. A recent study reported that the incidence of IBD in Asia showed a bimodal age distribution with increasing IBD prevalence, similar to the findings of Western studies. CD in Asian patients, especially those in East Asia, is characterized by ileocolonic involvement and perianal fistula. The frequency of extraintestinal manifestations, including primary sclerosing cholangitis, appears to be lower in Asia, but this finding should be interpreted with caution due to the transient and nonspecific nature of these manifestations. Although familial aggregation is lower in East Asia, it may also be explained by the low prevalence of IBD in Asia. Thus, more studies should focus on the differences in phenotypes in Asian IBD patients versus Western patients.

Development and Testing of a New Simplified Endoscopic Mucosal Assessment for Crohn's Disease: The SEMA-CD

OBJECTIVES

Endoscopic mucosal improvement is the gold standard for assessing treatment efficacy in clinical trials of Crohn's disease. Current endoscopic indices are not routinely used in clinical practice. The lack of endoscopic information in large clinical registries limits their use for research. A quick, easy, and accurate method is needed for assessing mucosal improvement for clinicians in real-world practice. We developed and tested a novel simplified endoscopic mucosal assessment for Crohn's disease (SEMA-CD).

METHODS

We developed a 5-point scale for ranking endoscopic severity of ileum and colon based on Simple Endoscopic Score for Crohn's disease (SES-CD). Central readers were trained to perform SES-CD and SEMA-CD. Pediatric patients with Crohn's disease undergoing colonoscopy were enrolled. Video recordings of colonoscopies were de-identified and randomly assigned to blinded central readers. The SES-CD and SEMA-CD were scored for each video. The SES-CD was considered the validated standard for comparison. Correlation was assessed with Spearman rho, inter- and intrarater reliability with kappa statistics.

RESULTS

Fifty-seven colonoscopies were read a total of 212 times. Correlation between SEMA-CD and SES-CD was strong (rho = 0.98, P < 0.0001). Inter-rater reliability for SEMA-CD was 0.80, and intrarater reliability was 0.83. Central readers rated SEMA-CD as easier than SES-CD.

CONCLUSION

The SEMA-CD accurately and reproducibly correlates with the standard SES-CD. Central readers viewed SEMA-CD as easier than SES-CD. Use of SEMA-CD in practice should enable collecting mucosal improvement information in large populations of patients. This will improve the quality of research that can be conducted in clinical registries. External validation is needed.

Perianal disease onset age is associated with distinct disease features and need for intestinal resection in perianal Crohn's disease: a ten-year hospital-based observational study in China

BACKGROUND AND AIMS

The significance of different ages of perianal disease (PD) onset in patients with perianal Crohn's disease (PCD) remains unknown. We aimed to investigate the impact of paediatric-onset PD (POP) and adult-onset PD (AOP) on the Crohn's disease (CD) course in a Chinese cohort.

METHODS

The medical records of diagnosed PCD patients from 2008 to 2018 were reviewed retrospectively. The cumulative incidence and predictors of intestinal resection were calculated using the Kaplan-Meier and logistic regression analysis.

RESULTS

Complex perianal fistulas (71.7% vs 50.0%, p = 0.011) and infliximab (IFX) treatment (33.3% vs 22.0%, p = 0.044) were more common among the POP patients (age < 18 years old, n = 84). A younger PD onset age (15.1 ± 2.9 vs 30.2 ± 10.5 years, p < 0.001) and shorter PCD diagnostic delay (12 vs 24 months, p = 0.033) was found in the POP cohort. AOP patients (age ≥ 18 years old, n = 209) had a higher rate of current smoking (12.9% vs 4.8%, p = 0.040), stricturing behaviour (42.1% vs 27.4%, p = 0.024) and intestinal resection (21.1% vs 4.8%, p = 0.001). The cumulative probability of intestinal resection in AOP patients was higher than that in POP patients (p = 0.007). In multivariable analysis, AOP (OR: 4.939, 95% CI 1.538-15.855, p = 0.007), stricturing behaviour (OR: 1.810, 95% CI 1.008-3.251, p = 0.047) and rectal inflammation (OR: 3.166, 95% CI 1.119-8.959, p = 0.030) were predictive factors for CD-related intestinal resection in all PCD patients. AOP patients with complex perianal fistula (OR: 2.257, 95% CI 1.041-4.891, p = 0.039) and POP patients with rectal inflammation (OR: 3.166, 95% CI 1.119-8.959, p = 0.030) were more likely to suffer intestinal resection. The IFX administration significantly decreased the rate of intestinal resection in AOP patients (r = - 0.900, p = 0.037).

CONCLUSIONS

The AOP patients have more complicated luminal disease and higher rate of intestinal resection than COP patients. The perianal diseases onset-age can provide clinical treatment guidance for individual management of CD patients.

Can Conventional and Diffusion-Weighted MR Enterography Biomarkers Differentiate Inflammatory from Fibrotic Strictures in Crohn's Disease?

Background and Objectives: To retrospectively assess the value of magnetic resonance enterography (MRE) parameters derived from conventional and diffusion weighted imaging (DWI) sequences to differentiate fibrotic strictures from inflammatory ones in adult patients with Crohn’s disease (CD), using surgical specimens as the histopathological reference standard. Material and Methods: Twenty-three patients with CD who had undergone surgical resection of ileal strictures with full-thickness histopathologic analysis within 3 months from preoperative MRE were included. Two radiologists blinded to histopathology in consensus evaluated the following biomarkers on MRE images matched to resected pathological specimens: T1 ratio, T2 ratio, enhancement pattern, mural thickness, pre-stenotic luminal diameter, and apparent diffusion coefficient (ADC). A blinded pathologist graded stricture histological specimens with acute inflammation score (AIS) and fibrosis score (FS). MRE measurements were correlated with the reference standard. Results: Inflammation and fibrosis coexisted in 78.3% of patients. T2 ratio was reduced in patients with severe fibrosis (p = 0.01). Pre-stenotic bowel dilatation positively correlated with FS (p = 0.002). The ADC value negatively correlated with FS (p < 0.001) and was different between FS grades (p < 0.05). The area under the receiver operating characteristic curve for discriminating between none and mild/moderate–severe bowel wall fibrosis was 0.75 for pre-stenotic bowel dilatation (sensitivity 100%, specificity 44.4%) and 0.97 for ADC (sensitivity 80%, specificity 100%). Conclusions: Inflammation and fibrosis often coexist in CD bowel strictures needing surgery. The combination of parameters derived from conventional MR sequences (T2 ratio, pre-stenotic dilatation) and from DWI (ADC) may provide a contribution to detect and grade bowel fibrosis in adult CD patients.

Predicting Outcomes in Pediatric Crohn's Disease for Management Optimization: Systematic Review and Consensus Statements From the Pediatric Inflammatory Bowel Disease-Ahead Program

BACKGROUND & AIMS

A better understanding of prognostic factors within the heterogeneous spectrum of pediatric Crohn's disease (CD) should improve patient management and reduce complications. We aimed to identify evidence-based predictors of outcomes with the goal of optimizing individual patient management.

METHODS

A survey of 202 experts in pediatric CD identified and prioritized adverse outcomes to be avoided. A systematic review of the literature with meta-analysis, when possible, was performed to identify clinical studies that investigated predictors of these outcomes. Multiple national and international face-to-face meetings were held to draft consensus statements based on the published evidence.

RESULTS

Consensus was reached on 27 statements regarding prognostic factors for surgery, complications, chronically active pediatric CD, and hospitalization. Prognostic factors for surgery included CD diagnosis during adolescence, growth impairment, NOD2/CARD15 polymorphisms, disease behavior, and positive anti-Saccharomyces cerevisiae antibody status. Isolated colonic disease was associated with fewer surgeries. Older age at presentation, small bowel disease, serology (anti-Saccharomyces cerevisiae antibody, antiflagellin, and OmpC), NOD2/CARD15 polymorphisms, perianal disease, and ethnicity were risk factors for penetrating (B3) and/or stenotic disease (B2). Male sex, young age at onset, small bowel disease, more active disease, and diagnostic delay may be associated with growth impairment. Malnutrition and higher disease activity were associated with reduced bone density.

CONCLUSIONS

These evidence-based consensus statements offer insight into predictors of poor outcomes in pediatric CD and are valuable when developing treatment algorithms and planning future studies. Targeted longitudinal studies are needed to further characterize prognostic factors in pediatric CD and to evaluate the impact of treatment algorithms tailored to individual patient risk.

The Gut Microbiome and the Triple Environmental Hit Concept of Inflammatory Bowel Disease Pathogenesis

The incidence of chronic inflammatory bowel diseases (IBDs), such as Crohn's disease (CD) and ulcerative colitis (UC) have significantly increased in recent decades implicating environmental effects. The developmental origin of disease concept provides a theoretical framework by which the complex interplay between environmental factors and host cells, particularly during vulnerable time periods, ultimately cause disease, such as IBD. Epigenetics has been proposed as the underlying mechanism within this concept, turning environmental triggers into stable changes of cellular function. Adding further to the complexity of IBD is the gut microbiome, which is equally responsive to the environment, and can impact host cell function, where recent findings underscore the stochastic and individualized nature of such effects. We review the microbiome literature through a novel triple environmental hit concept (priming, modulation, and trigger) of IBD pathogenesis. We propose that there are at least 3 distinct stages during an individual's lifespan where random/stochastic events driven by environmental influences are necessary for ultimately developing IBD. By this means, we speculate that microbiome-directed therapeutics carry potential for individualized prevention and dynamic treatment of IBD.

Association Between Steroid-Sparing Therapy and the Risk of Perianal Fistulizing Complications Among Young Patients With Crohn Disease

Importance

Perianal fistulizing complications (PFCs) develop in 15% to 30% of patients with Crohn disease (CD), are difficult to treat, worsen quality of life, increase cost of care, and commonly recur. Evidence-based strategies to prevent PFCs are lacking.

Objectives

To investigate the effectiveness of medical therapy for reducing risk of PFCs among young people with CD and to test the hypothesis that steroid-sparing therapy (SST) use would be associated with reduced risk of PFC development.

Design, Setting, and Participants

In this comparative effectiveness analysis of commercial administrative claims from January 1, 2001, through June 30, 2016, patients who did or did not initiate SST were matched via propensity score to adjust for all available confounders. Using Optum's Clinformatics Data Mart, a deidentified database of US commercial administrative claims, all patients aged 5 to 24 years with CD (January 1, 2001, through June 30, 2016) were identified. The index date was the CD diagnosis date. Patients with PFCs or SST use at or before CD diagnosis were excluded. The dates of analysis were October 2017 to February 2020.

Exposures

The primary exposure of interest was SST initiation, including immunomodulators and/or anti-tumor necrosis factor α (anti-TNFα) medications, initiated before either PFC development or the end of the study period.

Main Outcomes and Measures

The primary outcome was PFC development. Propensity score matching was used to balance baseline characteristics. Cox proportional hazards multivariable regression analyses were used to estimate hazard ratios (HRs) with 95% CIs for PFC development.

Results

Among 2214 young people with CD without PFCs identified, the mean (SD) age at CD diagnosis was 17.0 (4.5) years, and 1151 (52.0%) were male. Among the cohort, 1242 patients (56.1%) initiated SST before PFC development or the end of 24-month follow-up. After propensity score matching, 972 patients remained in each treatment group. Overall, 384 of 1944 (19.8%) developed PFCs within 2 years of the index date. The use of SST was associated with a 59% decreased risk of PFC development (hazard ratio [HR], 0.41; 95% CI, 0.33-0.52; P < .001) in 2 years compared with no SST use. Among those who developed PFCs, 55% fewer SST users underwent ostomy than SST nonusers. The use of immunomodulators alone, anti-TNFα alone, and combination therapy was associated with 52% (HR, 0.48; 95% CI, 0.37-0.62; P < .001), 47% (HR, 0.53; 95% CI, 0.36-0.78; P = .001), and 83% (HR, 0.17; 95% CI, 0.09-0.30; P < .001) reductions in the risk of 2-year PFC development, respectively, compared with no SST use.

Conclusions and Relevance

In this study, PFC development was common among young patients with CD. The use of SST was lower than expected. Compared with no SST, patients who initiated SST were 59% less likely to develop PFCs and fewer underwent ostomy. These results indicate that PFCs may be preventable and emphasize the importance of considering SST for all patients with CD.

Identifying perianal fistula complications in pediatric patients with Crohn's disease using administrative claims

Background

Although perianal fistulas occur commonly in pediatric Crohn’s disease (CD), evaluations of health services have been limited since no validated claims-based methods exist for identifying cases.

Objective

To develop and validate accurate case definitions for perianal fistulas among pediatric patients with CD from administrative claims.

Methods

Retrospective cohort study in which we developed and tested candidate case definitions for perianal fistula. Patients (age 5–21 years between 2005–2012) with CD enrolled in Michigan Medicaid with healthcare at University of Michigan were identified via claims. Medical records were obtained from all identified patients, whose entire records were abstracted. Medical record evidence for perianal fistula was considered the “gold standard” against which candidate case definitions were compared. The reference case definition of perianal fistula (ICD9 565.1) and candidate case definitions were evaluated.

Results

Of 843 patients identified via claims, 274 (33%) met CD criteria for inclusion. The true perianal fistula rate among CD patients was 18% (n = 49). The top-performing candidate case definition identified 15% (n = 42), had sensitivity of 77.6%, specificity of 98.2%, positive predictive value (PPV) 90.5%, negative predictive value (NPV) 95.3%, and area under receiver operator characteristic curve (ROC) of 0.88. In contrast, the reference case definition identified 9% (n = 26), sensitivity 51.0%, specificity 99.6%, PPV 96.2%, NPV 90.3%, and had an area under ROC of 0.75.

Conclusions

We demonstrated that it is feasible to use administrative claims data to accurately identify pediatric patients with perianal fistula complications. Claims-based case definitions were found to be highly accurate through medical record review, providing a high degree of confidence for future studies where chart review is not feasible. These claims-based methods can be applied to claims data in other settings for the evaluation of health services utilization as well as to assess the comparative effectiveness of prevention and treatment strategies.

Carbohydrate Monotony as Protection and Treatment for Inflammatory Bowel Disease

The nutritional developmental origins of inflammatory bowel disease[s] (IBDs: Crohn's disease or Crohn disease [CD] and ulcerative colitis [UC]) and their diet-based treatments continue to receive increasing attention. There is growing evidence for the success of nutrition-based treatments, such as exclusive enteral nutrition [EEN] and the specific carbohydrate diet [SCD], in both paediatric and adult patients. Beyond these two dietary interventions, symptomatic benefit in IBD has also been shown from a gluten-free diet [GFD] and paleolithic diet [PALEO], among others. These nutritional therapies may point to critical factors in not only the pathology, but also the pathogenesis of the disease group. It is difficult, however, to discern a common element within the large number of diet-based causation theories [e.g. emulsifiers, processed foods, refrigeration, increased total fat intake, low fibre intake, carbohydrate dominant food, etc.] and the varied dietary treatments of IBD. This Viewpoint article highlights that carbohydrate variation links diet-based causation theories, and that carbohydrate monotony or persistence is the commonly shared characteristic of diet-based IBD therapy. Further research directed towards carbohydrate monotony may critically advance the prevention and treatment of these highly morbid conditions.

Challenges in IBD Research: Preclinical Human IBD Mechanisms

Preclinical human IBD mechanisms is part of five focus areas of the Challenges in IBD research document, which also include environmental triggers, novel technologies, precision medicine and pragmatic clinical research. The Challenges in IBD research document provides a comprehensive overview of current gaps in inflammatory bowel diseases (IBD) research and delivers actionable approaches to address them. It is the result of a multidisciplinary input from scientists, clinicians, patients, and funders, and represents a valuable resource for patient centric research prioritization. In particular, the preclinical human IBD mechanisms manuscript is focused on highlighting the main research gaps in the pathophysiological understanding of human IBD. These research gap areas include: 1) triggers of immune responses; 2) intestinal epithelial homeostasis and wound repair; 3) age-specific pathophysiology; 4) disease complications; 5) heterogeneous response to treatments; and 6) determination of disease location. As an approach to address these research gaps, the prioritization of reverse translation studies is proposed in which clinical observations are the foundation for experimental IBD research in the lab, and for the identification of new therapeutic targets and biomarkers. The use of human samples in validating basic research findings and development of precision medicine solutions is also proposed. This prioritization aims to put emphasis on relevant biochemical pathways and humanized in vitro and in vivo models that extrapolate meaningfully to human IBD, to eventually yield first-in-class and effective therapies.

Response to treatment is more important than disease severity at diagnosis for prediction of early relapse in new-onset paediatric Crohn's disease

BACKGROUND

Paediatric Crohn's disease is characteried by frequently relapsing disease which may lead to hospitalisations and complications.

AIM

To develop predictive models for early relapse following first remission.

METHODS

The GROWTH CD prospective inception cohort was designed to predict risk for early disease relapse and poor outcomes. Newly diagnosed children underwent endoscopies and imaging. They were phenotyped and followed at scheduled visits through 78 weeks for relapses. Twenty-eight dichotomous and continuous variables were assessed at baseline and week 12, including phenotype, inflammatory markers, disease activity (PCDAI) and other markers. Clinical relapses defined as PCDAI >10 after remission were recorded using a relapse form. Logistic regression & risk modelling was performed.

RESULTS

We enrolled 282 eligible patients of whom 178 (63.6%) patients achieved steroid free remission by week 12. Disease complications developed in 22/76(29%) of patients with relapse compared to 20/206 (9.7%) without relapse (P = 0.01). Multivariable analysis demonstrated that while variables from age/gender at diagnosis were not predictive, week 12 variables including PCDAI >5 (P = 0.02), CRP >20 mg/L (P = 0.02), and faecal calprotectin >400 µg/g (P = 0.03) as optimal cut-offs were associated with increased risk of relapse. A prediction model for patients in remission including gender, age, week 12 PCDAI, calprotectin and CRP had sensitivity 43%, specificity 92%, PPV 78%, NPV 71% for relapse.

CONCLUSIONS

Early relapses were associated with a higher risk for disease complications at followup. Relapse prediction based on week 12 disease activity or inflammation is superior to prediction using data from diagnosis.

Efficacy of Adalimumab for Treatment of Perianal Fistula in Children with Moderately to Severely Active Crohn's Disease: Results from IMAgINE 1 and IMAgINE 2

BACKGROUND AND AIMS

Adalimumab has been shown to be more effective than placebo in healing fistulae in adults with moderately to severely active Crohn's disease. The efficacy and safety of adalimumab in healing fistulae in children/adolescents with Crohn's disease from the 52-week IMAgINE 1 clinical trial, and its open-label extension IMAgINE 2, are reported.

METHODS

Children/adolescents with perianal fistulae at baseline of IMAgINE 1 were assessed for fistula closure and improvement during IMAgINE 1 [Weeks 0-52] and from Week 0 of IMAgINE 2 [Week 52 of IMAgINE 1] through to Week 240 of IMAgINE 2 using non-responder imputation.

RESULTS

A total of 36 children/adolescents had fistulae at baseline of IMAgINE 1 and were included in the analysis. Fistula closure and improvement were observed in 44.4% and 52.8%, respectively, at Week 12. Rates of closure and improvement were maintained throughout the analysis period to Week 292. No new safety signals were identified.

CONCLUSIONS

In children/adolescents with moderately to severely active, fistulizing Crohn's disease, adalimumab induced perianal fistula closure and improvement within 12 weeks of treatment, with rates that were sustained for more than 5 years. The safety profile of adalimumab in patients with fistulae at baseline was similar to that of the overall population in IMAgINE 1/2. ClinicalTrials.gov identifiers: IMAgINE 1 (NCT00409682); IMAgINE 2 (NCT00686374).

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

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

Penetrating Crohn disease: does it occur in the absence of stricturing disease?

PURPOSE

To establish the relationship between penetrating complications and bowel luminal narrowing/stricturing disease in pediatric Crohn disease (CD).

MATERIALS AND METHODS

This retrospective study was IRB-approved and HIPAA compliant with waiver of informed consent. CT and MRI examinations describing intra-abdominal penetrating complications in CD patients ≤ 18 years old between January 1, 2009 and March 31, 2016 were reviewed to document: type of complication, affected bowel segment, minimum bowel luminal diameter, maximum upstream diameter, location of penetrating complication relative to luminal narrowing, length of narrowed bowel segment, and the presence of active bowel wall inflammation. Data were summarized using descriptive statistics including means, standard deviations, as well as counts and percentages.

RESULTS

A total of 52 penetrating complications were identified in 45 patients. Mean patient age was 15.7 ± 2.2 years (range 11-18 years) with 25/45 (56%) boys. Nearly all penetrating complications (51/52, 98%) were associated with a minimum bowel luminal diameter of ≤ 2 mm, with no visible lumen in 26/52 (50%). Mean maximum upstream diameter was 2.8 ± 0.8 cm (range 1.2-5.2 cm), and 17/52 (33%) penetrating complications were associated with > 3 cm upstream diameter. The mean ratio of maximum to minimum luminal diameter was 26.2 ± 8.8 (range 3.6-52.0). Active intestinal inflammation was associated with 100% (52/52) of penetrating complications. Nearly every penetrating complication (51/52, 98%) involved the terminal or distal ileum.

CONCLUSIONS

Penetrating complications in pediatric CD nearly always occur in the setting of considerable luminal narrowing or stricture and active intestinal inflammation.

The Role of Combination Therapy in Pediatric Inflammatory Bowel Disease: A Clinical Report from the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition

The treatment goal for children suffering from inflammatory bowel disease has been evolving with biologic therapies like anti-tumor necrosis factor agents assuming a more central role in treatment of more aggressive and extensive phenotype. Earlier introduction of anti-tumor necrosis factor agents have shown to be more effective and may even alter the natural history of inflammatory bowel disease. Development of anti-drug antibodies, however, limits long-term usage and leads to dose adjustment in almost half of patients treated with these medications. One of the strategies to minimize the development of anti-drug antibodies has been concomitant use of immunomodulator medications, resulting in fewer infusion reactions and sustained trough levels, potentially lowering the need for dose adjustments. Balanced with these benefits of optimized dosing and likely more sustained response, however, is the concern about increased risk of complications, such as infections and malignancies. The current manuscript reviews the available pediatric literature regarding efficacy, safety, and side effect profile of combination (immunomodulator and biologics) therapy in pediatric Crohn disease and ulcerative colitis, with particular emphasis on cost constraints, and recommendations for selection of patients who would benefit most from combination therapy.

Incidence and Risk Factors for Perianal Disease in Pediatric Crohn Disease Patients Followed in CEDATA-GPGE Registry

OBJECTIVES

Perianal disease (PD) with fistula and/or abscess formation is a severe complication in Crohn disease (CD). We examined prevalence, incidence, and risk factors for PD development in a pediatric CD cohort.

METHODS

Patients with CD from the prospective, multicenter registry for inflammatory bowel disease from Germany and Austria (CEDATA-GPGE) were included if diagnosed at the age of 18 years or younger, registered within 3 months after diagnosis, and having at least 2 follow-up visits within the first year of registration. We examined potential risk factors for PD with Kaplan-Meier analysis and a final Cox model considering sex, family history of inflammatory bowel disease, extraintestinal manifestations, disease location, and induction therapy (corticosteroids or nutritional therapy).

RESULTS

Of 2406 patients with CD, 742 fulfilled inclusion criteria (59% boys, mean age at diagnosis 12.4 ± 3.4 years). PD was present at diagnosis in 41 patients (5.5%; 80.9% boys), whereas 32 patients (4.3%, 81.3% male) developed PD during follow-up (mean 2.0 ± 1.6 years). The cumulative incidence of PD at 12 and 36 months after diagnosis was 3.5% and 7.5%, respectively. Potential risk factors for PD development during follow-up were male sex (hazard ratio = 3.2, [95%; confidence interval 1.2-7.8]) and induction therapy with corticosteroids (hazard ratio = 2.5 [1.1-5.5]). Diagnostic evaluation at PD diagnosis was incomplete in 40% of affected subjects. PD resolved within 1 year in 50% of cases.

CONCLUSIONS

Approximately 10% of CD patients in our cohort suffered from PD within the first 3 years of their disease. Male sex and initial corticosteroid therapy were associated with an increased risk to develop PD after diagnosis.

Prevalence of intestinal complications in inflammatory bowel disease: a comparison between paediatric-onset and adult-onset patients

INTRODUCTION

Intestinal complications in inflammatory bowel disease indicate active inflammation and typically result in the intensification of therapy.

AIM

To analyse whether the rates of intestinal complications were associated with age at disease onset.

PATIENTS AND METHODS

Data from 1506 individuals with Crohn's disease (CD) and 1201 individuals with ulcerative colitis (UC) were obtained from the Swiss inflammatory bowel disease cohort study database, classified into groups on the basis of age at diagnosis (<10, <17, <40 and >40 years of age), and retrospectively analysed.

RESULTS

In CD patients, the rates of stricturing (29.1-36.2%), abdominal penetrating disease (11.9-18.2%), resectional surgery (17.9-29.8%) and perianal disease (14.7-34.0%) were correlated with disease duration, but not age at diagnosis. However, paediatric-onset CD was associated with higher rates of multiple, rectal and anal strictures and earlier colon surgery. In addition, perianal disease occurred earlier, required earlier surgical intervention, and was more often combined with stricturing and penetrating disease. Finally, anal fissures were more prevalent among younger patients. In UC patients, the rates of progression or extension of disease (0-25.8%) and colectomy (3.0-8.7%) were dependent on disease duration, but not age at disease onset. Paediatric-onset disease was associated with a higher rate of extensive colitis at diagnosis and earlier progression or extension of disease, and nonsurgically treated patients with the youngest ages at onset more frequently required antitumour necrosis factor-α treatments.

CONCLUSION

The higher rates of intestinal complications, including those of the small and large bowel and in the anal region, in paediatric-onset CD patients point towards a level of inflammation that is more difficult to control. Similar findings were also evident in UC patients.

Perianal Crohn Disease in a Large Multicenter Pediatric Collaborative

BACKGROUND

Although perianal complications of Crohn disease (CD) are commonly encountered in clinical practice, the epidemiology of perianal CD among populations of children is poorly understood. We sought to characterize the prevalence of perianal disease in a large and diverse population of pediatric patients with CD.

METHODS

We conducted retrospective analyses from a prospective observational cohort, the ImproveCareNow Network (May 2006-October 2014), a multicenter pediatric inflammatory bowel disease quality improvement collaborative. Clinicians prospectively documented physical examination and phenotype classification at outpatient visits. Perianal examination findings and concomitant phenotype change were used to corroborate time of new-onset perianal disease. Results were stratified by age, sex, and race and compared across groups with logistic regression. Cumulative incidence was estimated using Kaplan-Meier analyses and compared between groups with Cox proportional hazard regression models.

RESULTS

The registry included 7076 patients with CD (41% girls). Missing/conflicting entries resulted in 397 (6%) patient exclusions. Among the remaining 6679 cases, 1399 (21%) developed perianal disease. Perianal disease was more common among boys (22%) than girls (20%; P = 0.013) and developed sooner after diagnosis among those with later rather than early onset disease (P < 0.001). Perianal disease was also more common among blacks (26%) compared with whites (20%; P = 0.017). Asians with later onset CD developed perianal disease earlier in their disease course (P = 0.01). There was no association between disease location or nutritional status at diagnosis and later development of perianal disease.

CONCLUSIONS

In this large multicenter collaborative, we found that perianal disease is more common among children with CD than previously recognized. Differences in the development of perianal disease were found across racial and other subgroups. Treatment strategies are needed to prevent perianal disease development.

Surgical Management of Crohn Disease in Children: Guidelines From the Paediatric IBD Porto Group of ESPGHAN

The incidence of Crohn disease (CD) has been increasing and surgery needs to be contemplated in a substantial number of cases. The relevant advent of biological treatment has changed but not eliminated the need for surgery in many patients. Despite previous publications on the indications for surgery in CD, there was a need for a comprehensive review of existing evidence on the role of elective surgery and options in pediatric patients affected with CD. We present an expert opinion and critical review of the literature to provide evidence-based guidance to manage these patients. Indications, surgical options, risk factors, and medications in pre- and perioperative period are reviewed in the light of available evidence. Risks and benefits of surgical options are addressed. An algorithm is proposed for the management of postsurgery monitoring, timing for follow-up endoscopy, and treatment options.

Clinical Characteristics and Long-Term Outcomes of Paediatric Crohn's Disease: A Single-Centre Experience

BACKGROUND AND AIMS

Although paediatric Crohn's disease [CD] has a different phenotype and clinical course to adult CD, its clinical features and surgical risks are poorly defined, especially in Asian countries. The aim of this study was to investigate the clinical features and long-term outcomes of paediatric CD in a Korean population.

METHODS

We retrospectively analysed 594 patients who were younger than 18 years of age at CD diagnosis between 1987 and 2013. Patient characteristics at diagnosis according to the Paris classification and clinical courses were analysed.

RESULTS

The male-to-female ratio was 2.4:1 and the median age at CD diagnosis was 15 years [range, 2-17 years]. A positive first-degree family history of inflammatory bowel disease was present in 30 patients [5.1%]. Sixty-seven patients [11.3%] showed growth impairment. The cumulative probabilities of perianal fistula at 1, 5 and 10 years after diagnosis were 50.3%, 54.9% and 57.6%, respectively. The cumulative probabilities of anti-tumour necrosis factor treatment at 1, 5, 10 and 20 years after diagnosis were 10.7%, 25.8%, 41.8% and 76.3%, respectively. The cumulative probabilities of intestinal resection at 1, 5, 10 and 20 years after diagnosis were 4.5%, 17.2%, 33.9% and 62.9 %, respectively. In multivariate analysis, complicated behaviour and isolated colonic location [L2] at diagnosis were associated with an increased and decreased risk of intestinal resection, respectively.

CONCLUSIONS

Our study is the largest Asian paediatric study which applied the Paris classification to patients. This study provides detailed information on disease phenotype and long-term clinical outcomes in a large cohort of Asian children with CD.

Current tecniques and new perpectives research of magnetic resonance enterography in pediatric Crohn's disease

Crohn's disease affects more than 500000 individuals in the United States, and about 25% of cases are diagnosed during the pediatric period. Imaging of the bowel has undergone dramatic changes in the past two decades. The endoscopy with biopsy is generally considered the diagnostic reference standard, this combination can evaluates only the mucosa, not inflammation or fibrosis in the mucosa. Actually, the only modalities that can visualize submucosal tissues throughout the small bowel are the computed tomography (CT) enterography (CTE) with the magnetic resonance enterography (MRE). CT generally is highly utilized, but there is growing concern over ionizing radiation and cancer risk; it is a very important aspect to keep in consideration in pediatric patients. In contrast to CTE, MRE does not subject patients to ionizing radiation and can be used to detect detailed morphologic information and functional data of bowel disease, to monitor the effects of medical therapy more accurately, to detect residual active disease even in patients showing apparent clinical resolution and to guide treatment more accurately.

MR enterography-histology comparison in resected pediatric small bowel Crohn disease strictures: can imaging predict fibrosis?

BACKGROUND

Crohn disease is a chronic inflammatory condition that can lead to intestinal strictures. The presence of fibrosis within strictures alters optimal management but is not reliably detected by current imaging methods.

OBJECTIVE

To correlate the MRI features of surgically resected small-bowel strictures in pediatric Crohn disease with histological inflammation and fibrosis scoring.

MATERIALS AND METHODS

We included children with Crohn disease who had symptomatic small-bowel strictures requiring surgical resection and had preoperative MR enterography (MRE) within 3 months of surgery (n = 20). Two blinded radiologists reviewed MRE examinations to document stricture-related findings. A pediatric pathologist scored stricture histological specimens for fibrosis (0-4) and inflammation (0-4). MRE findings were correlated with histological data using Spearman correlation (ρ) and exact logistic regression analysis.

RESULTS

There was significant positive correlation between histological bowel wall fibrosis and inflammation in resected strictures (ρ = 0.55; P = 0.01). Confluent transmural histological fibrosis was associated with pre-stricture upstream small-bowel dilatation >3 cm at univariate (odds ratio [OR] = 51.7; 95% confidence interval [CI]: 7.6- > 999.9; P = 0.0002) and multivariate (OR = 43.4; 95% CI: 6.1- > 999.9; P = 0.0006, adjusted for age) analysis. The degree of bowel wall T2-weighted signal intensity failed to correlate with histological bowel wall fibrosis or inflammation (P-values >0.05). There were significant negative correlations between histological fibrosis score and patient age at resection (ρ = -0.48, P = 0.03), and time from diagnosis to surgery (ρ = -0.73, P = 0.0002).

CONCLUSION

Histological fibrosis and inflammation co-exist in symptomatic pediatric Crohn disease small-bowel strictures and are positively correlated. Pre-stenotic upstream small-bowel dilatation greater than 3 cm is significantly associated with confluent transmural fibrosis.

Eosinophils and IL-33 Perpetuate Chronic Inflammation and Fibrosis in a Pediatric Population with Stricturing Crohn's Ileitis

BACKGROUND

Fibrostenosis and stricture are well-recognized endpoints in Crohn's disease (CD). We hypothesized that stricturing CD is characterized by eosinophilia and epithelial IL-33. We proposed that eosinophil exposure to IL-33 would perpetuate inflammatory chronicity and subsequent fibrostenosis.

METHODS

We performed a retrospective study of 74 children with inflammatory and stricturing ileal CD comparing clinicopathological features to immunohistochemical measures of eosinophilia and IL-33. To scrutinize eosinophil patterns, we developed a novel eosinophil peroxidase score encompassing number, distribution, and degranulation. Human eosinophils and intestinal fibroblasts were cultured with IL-33 and IL-13, and inflammatory and remodeling parameters were assessed. Antieosinophil therapy was also administered to the Crohn's-like ileitis model (SAMP1/SkuSlc).

RESULTS

Our novel eosinophil peroxidase score was more sensitive than H&E staining, revealing significant differences in eosinophil patterns, comparing inflammatory and stricturing pediatric CD. A significant relationship between ileal eosinophilia and complicated clinical/histopathological phenotype including fibrosis was determined. IL-33 induced significant eosinophil peroxidase secretion and IL-13 production. Exposure to eosinophils in the presence of IL-33, "primed" fibroblasts to increase proinflammatory cytokines (TNF-α, IL-1β, and IL-6), eosinophil-associated chemokines (CCL24 and CCL26), and IL-13Rα2 production. Production of fibrogenic molecules (collagen 1A2, fibronectin, and periostin) increased after exposure of "primed" fibroblasts to IL-13. Epithelial-IL-33 was increased in pediatric Crohn's ileitis and strongly associated with clinical and histopathological activity, ileal eosinophilia, and complicated fibrostenotic disease. SAMP1/SkuSlc eosinophil-targeted treatment resulted in significant improvements in inflammation and remodeling.

CONCLUSIONS

Our study of specimens from pediatric patients with ileal CD linked eosinophil patterns and IL-33 to fibrosis and suggested that these may contribute to the perpetuation of inflammation and subsequent stricture in pediatric CD.

Efficacy and safety of adalimumab after infliximab failure in pediatric Crohn disease

OBJECTIVES

The objective of the present study was to evaluate the effectiveness and safety of adalimumab (ADA) in children with Crohn disease (CD) who experienced infliximab (IFX) failure at the population level.

METHODS

The present retrospective study included all of the children with CD from a pediatric-onset population-based cohort who received ADA before 18 years because of IFX failure or intolerance. Efficacy of ADA was evaluated using the physician's global assessment score, C-reactive protein and orosomucoid, and nutritional and growth indicators.

RESULTS

A total of 27 children with CD received ADA. Median age at CD diagnosis and at ADA initiation was 11 years (Q1 = 9; Q3 = 12) and 15 years (12; 15), respectively. After a median follow-up of 16 (8; 26) months after ADA initiation, ADA had clinical benefit as measured by the physical global assessment score in 19 patients (70%). Cumulative probability of failure to ADA treatment was 38% at 6 months and 55% at 1 year. Eight patients had a primary failure (30%) and 5 of 19 (26%) a secondary failure to ADA. Furthermore, 11 patients (40%) experienced a total of 19 adverse effects. No serious adverse effects were observed and none resulted in ADA discontinuation. There was no significant change in growth and nutritional patterns during the study period, but we found a significant decrease in median C-reactive protein (15 mg/L [4; 44] vs 9 mg/L [3; 19]; P = 0.05) and orosomucoid (1.6 g/L [1.5; 2.6] vs 1.1 g/L [0.8; 1.9]; P = 0.001) from ADA initiation to maximal follow-up in patients responding to ADA.

CONCLUSIONS

In the present population-based cohort of pediatric-onset CD with IFX failure, treatment with ADA was safe and effective in two-thirds of patients.

Loss of n-6 fatty acid induced pediatric obesity protects against acute murine colitis

Dietary influences may affect microbiome composition and host immune responses, thereby modulating propensity toward inflammatory bowel diseases (IBDs): Crohn disease (CD) and ulcerative colitis (UC). Dietary n-6 fatty acids have been associated with UC in prospective studies. However, the critical developmental period when (n-6) consumption may induce UC is not known. We examined the effects of transiently increased n-6 consumption during pediatric development on subsequent dextran-sulfate-sodium (DSS)-induced acute murine colitis. The animals transiently became obese then rapidly lost this phenotype. Interestingly, mice were protected against DSS colitis 40 days after n-6 consumption. The transient high n-6-induced protection against colitis was fat type- and dietary reversal-dependent and could be transferred to germ-free mice by fecal microbiota transplantation. We also detected decreased numbers of chemokine receptor (Cxcr)5(+) CD4(+) T cells in the mesenteric lymph nodes (MLNs) of transiently n-6-fed mice. Further experiments revealed that anti-chemokine ligand (Cxcl)13 (the ligand of Cxcr5) antibody treatment decreased DSS colitis severity, implicating the importance of the Cxcr5-Cxcl13 pathway in mammalian colitis. Consecutively, we found elevated CXCL13 concentrations (CD: 1.8-fold, P = 0.0077; UC: 1.9-fold, P = 0.056) in the serum of untreated pediatric IBD patients. The human serologic observations supported the translational relevance of our findings.

Pediatric MR enterography: technique and approach to interpretation-how we do it

Magnetic resonance (MR) enterography is an increasingly important pediatric imaging modality that is most often used to evaluate inflammatory bowel disease ( IBD inflammatory bowel disease ), while sparing children and adolescents from potential risks of ionizing radiation exposure. MR enterography allows for evaluation of the bowel lumen and wall, adjacent mesentery and soft tissues, as well as a variety of extraintestinal abdominopelvic IBD inflammatory bowel disease manifestations. While MR enterography can be used to initially confirm the diagnosis of IBD inflammatory bowel disease , particularly small bowel Crohn disease, it has also proven useful in assessing the degree inflammatory activity over time, serving as a radiologic biomarker for response to medical therapy, and identifying a variety of disease-related complications, including strictures, fistulae, and abscesses. The purpose of this review article is to provide radiologists with a systematic approach for MR enterography review and interpretation in children and adolescents with known or suspected of having IBD inflammatory bowel disease and to illustrate both common and infrequent but important imaging findings. Additionally, the authors will present their well-established and clinically successful pediatric MR enterography protocol, up-to-date clinical indications for MR enterography, and briefly mention the role of MR enterography in assessing non- IBD inflammatory bowel disease abnormalities affecting the bowel. Online supplemental material is available for this article .

Pain management in patients with inflammatory bowel disease: translational approaches from bench to bedside

Abdominal pain is a common symptom in patients with inflammatory bowel disease (IBD) that negatively affects quality of life and can lead to increased health-seeking behavior. Although abdominal pain has been traditionally attributed to inflammation, there is growing literature demonstrating the existence of functional abdominal pain in patients with IBD, of which there are a variety of potential causes. Thus, when approaching a patient with IBD who has abdominal pain, in addition to IBD-related complications (e.g., inflammation/stricture), it is important to screen for related contributors, including peripheral factors (visceral hypersensitivity, bacterial overgrowth, and bowel dysmotility) and centrally mediated neurobiological and psychosocial underpinnings. These central factors include psychological symptoms/diagnoses, sleep disturbance, and stress. Opioid-induced hyperalgesia (e.g., narcotic bowel syndrome) is also growing in recognition as a potential central source of abdominal pain. This review draws from clinical studies and animal models of colitis and abdominal pain to consider how knowledge of these potential etiologies can be used to individualize treatment of abdominal pain in patients with IBD, including consideration of potential novel treatment modalities for the future. Accurate assessment of the source(s) of pain in patients with IBD can help guide appropriate diagnostic workup and use of disease-modifying therapy.

Magnetic resonance enterography in the evaluation of Crohn's disease: a primer for the gastroenterologist

The assessment of disease location, severity, and complications is critical in guiding the choice of Crohn's disease therapy. Cross-sectional imaging studies have therefore had a paramount role in accurately staging Crohn's disease. Traditionally, computed tomography was the test of choice in confirming/excluding strictures, fistulae, and abscesses. Magnetic resonance imaging is now replacing computed tomography because it eliminates radiation risks. This review provides a primer for the gastroenterologist on magnetic resonance enterography in Crohn's disease.

Inflammatory bowel disease in pediatric and adolescent patients: A biomolecular and histopathological review

Crohn’s disease (CD) and ulcerative colitis (UC) are the two main forms of inflammatory bowel disease (IBD) with both overlapping and distinct clinical, pathological and biomolecular features. It has been suggested that pediatric IBD is a distinct disease entity, with probably different disease subtypes.The aim of this study is to review and summarize the evolution of the current concept of pediatric IBD. The results of this review reinforce the idea that pediatric CD and UC may be further classified in various clinicopathologic entities. For clinicians and pathologists convenience, practical algorithms for the distinction of the various subphenotypes of pediatric IBD are also provided.

Use of the star sign to diagnose internal fistulas in pediatric patients with penetrating Crohn disease by MR enterography

Development of internal fistula due to extramural spread of inflammatory bowel disease is a characteristic feature of penetrating disease in patients with Crohn disease. The "star sign" is a radiological finding of internal fistula that has previously been described in the gastroenterology literature in adult Crohn disease patients undergoing MR enteroclysis. The goal of this paper is to review the clinical and imaging features of penetrating disease in pediatric Crohn disease patients, highlighting the star sign as a useful diagnostic tool for diagnosing internal fistula in children by MR enterography. The recognition of penetrating complications by MR imaging can have important therapeutic and prognostic implications.

Predictors of abdominal pain in depressed pediatric inflammatory bowel disease patients

BACKGROUND

Pediatric patients with inflammatory bowel disease (IBD) have high rates of abdominal pain. The study aims were to (1) evaluate biological and psychological correlates of abdominal pain in depressed youth with IBD and (2) determine predictors of abdominal pain in Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

Seven hundred sixty-five patients aged 9 to 17 years with IBD seen over 3 years at 2 sites were screened for depression. Depressed youth completed comprehensive assessments for abdominal pain, psychological (depression and anxiety), and biological (IBD-related, through disease activity indices and laboratory values) realms.

RESULTS

Two hundred seventeen patients with IBD (161 CD, 56 UC) were depressed. One hundred sixty-three (120 CD, 43 UC) patients had complete abdominal pain index scores. In CD, abdominal pain was associated with depression (r = 0.33; P < 0.001), diarrhea (r = 0.34; P = 0.001), erythrocyte sedimentation rate (r = 0.22; P = 0.02), low albumin (r = 0.24; P = 0.01), weight loss (r = 0.33; P = 0.001), and abdominal tenderness (r = 0.38, P = 0.002). A multivariate model with these significant correlates represented 32% of the variance in pain. Only depression (P = 0.03), weight loss (P = 0.04), and abdominal tenderness (P = 0.01) predicted pain for patients with CD. In UC, pain was associated with depression (r = 0.46; P = 0.002) and nocturnal stools (r = 0.32; P = 0.046). In the multivariate model with these significant correlates, 23% of the variance was explained and only depression (P = 0.02) predicted pain.

CONCLUSIONS

The psychological state of pediatric patients with IBD may increase the sensitivity to abdominal pain. Thus, screening for and treating comorbid depression may prevent excessive medical testing and unnecessary escalation of IBD medications.

DNA methylation-associated colonic mucosal immune and defense responses in treatment-naïve pediatric ulcerative colitis

Inflammatory bowel diseases (IBD) are emerging globally, indicating that environmental factors may be important in their pathogenesis. Colonic mucosal epigenetic changes, such as DNA methylation, can occur in response to the environment and have been implicated in IBD pathology. However, mucosal DNA methylation has not been examined in treatment-naïve patients. We studied DNA methylation in untreated, left sided colonic biopsy specimens using the Infinium HumanMethylation450 BeadChip array. We analyzed 22 control (C) patients, 15 untreated Crohn’s disease (CD) patients, and 9 untreated ulcerative colitis (UC) patients from two cohorts. Samples obtained at the time of clinical remission from two of the treatment-naïve UC patients were also included into the analysis. UC-specific gene expression was interrogated in a subset of adjacent samples (5 C and 5 UC) using the Affymetrix GeneChip PrimeView Human Gene Expression Arrays. Only treatment-naïve UC separated from control. One-hundred-and-twenty genes with significant expression change in UC (> 2-fold, P &lt; 0.05) were associated with differentially methylated regions (DMRs). Epigenetically associated gene expression changes (including gene expression changes in the IFITM1, ITGB2, S100A9, SLPI, SAA1, and STAT3 genes) were linked to colonic mucosal immune and defense responses. These findings underscore the relationship between epigenetic changes and inflammation in pediatric treatment-naïve UC and may have potential etiologic, diagnostic, and therapeutic relevance for IBD.

New serological markers in pediatric patients with inflammatory bowel disease

The spectrum of serological markers associated with inflammatory bowel disease (IBD) is rapidly growing. Due to frequently delayed or missed diagnoses, the application of non-invasive diagnostic tests for IBD, as well as differentiation between ulcerative colitis (UC) and Crohn’s disease (CD), would be useful in the pediatric population. In addition, the combination of pancreatic autoantibodies and antibodies against Saccharomyces cerevisiae antibodies/perinuclear cytoplasmic antibody (pANCA) improved the sensitivity of serological markers in pediatric patients with CD and UC. Some studies suggested that age-associated differences in the patterns of antibodies may be present, particularly in the youngest children. In CD, most patients develop stricturing or perforating complications, and a significant number of patients undergo surgery during the disease course. Based on recent knowledge, serum antibodies are qualitatively and quantitatively associated with complicated CD behavior and CD-related surgery. Pediatric UC is characterized by extensive colitis and a high rate of colectomy. In patients with UC, high levels of anti-CBir1 and pANCA are associated with the development of pouchitis after ileal pouch-anal anastomosis. Thus, serologic markers for IBD can be applied to stratify IBD patients into more homogeneous subgroups with respect to disease progression. In conclusion, identification of patients at an increased risk of rapid disease progression is of great interest, as the application of early and more aggressive pharmaceutical intervention could have the potential to alter the natural history of IBD, and reduce complications and hospitalizations.

Disease course and efficacy of medical therapy in stricturing paediatric Crohn's disease

BACKGROUND

Stricturing is the most common complicated phenotype in paediatric Crohn's disease, but only few studies have described its course, while data on the outcome of medical treatment are scanty.

AIM

To retrospectively describes the course of paediatric stricturing Crohn's disease and assess clinical and imaging response to medical therapy.

PATIENTS AND METHODS

Thirty-six patients with stricturing Crohn's disease were identified by our department database. Paediatric Crohn's disease activity index, need of surgery and magnetic resonance were evaluated as outcomes at 6, 12, 18 and 24 months after detection of stenosis.

RESULTS

Strictures were ileal, ileocolonic and colonic in 61%, 28% and 11% of patients. Thirteen (36%) had stricturing disease at the diagnosis of Crohn's disease, while 64% developed it at the follow-up. At baseline, 89% had medical treatment, while 11% surgery. At 6, 12, 18, and 24 months, 53%, 50%, 42%, and 35% had complete response to medical treatment, respectively. Overall, 44% were unresponsive to medical therapy and required surgery at the follow-up. Responders and non-responders significantly differed for inflammatory imaging findings at the stenosis detection.

CONCLUSIONS

A stricturing phenotype is not uncommon at the diagnosis of Crohn's disease in children. Medical therapy seems poorly effective in avoiding intestinal resection. Magnetic resonance imaging is valuable in identifying patients who will benefit from medical therapy.

Distinct phenotypes of children with perianal perforating Crohn's disease

PURPOSE

Perianal perforating disease (PF) has been reported in approximately 15% of children with Crohn's disease (CD). It is unknown whether children who present with PF at the time of diagnosis have a different course than those that develop PF while on therapy.

METHODS

From a prospective, single institution observational registry of children diagnosed with CD, we identified children with perianal perforating CD, defined as perianal abscesses and/or fistulae. Patients who presented with perianal perforating CD (PF-CD0) were compared to those who developed perianal perforating CD (PF-CD1) after initial diagnosis.

RESULTS

Thirty-eight of 215 (18%) children with CD had PF-CD during a median follow up of 4.5 years. Patients with PF-CD0 (n=26) tended to be more likely male (81% vs. 50%, p=0.07) and younger (9.3 yrs vs. 12.5 yrs, p=0.02). PF-CD1 (n=12) patients were more likely to require diverting ileostomy (42% vs. 8%, p=0.02) and colectomy (33% vs. 4%, p=0.03). Multivariable analysis predicted increased rate of diverting ileostomy in the PF-CD1 group (p=0.007, OR 19.1, 95% CI 1.6-234.8).

CONCLUSION

Pediatric CD patients who develop PF while on therapy for CD have a more severe phenotype and are more likely to require diverting ileostomy or colectomy compared to those who present with PF-CD.

Genome-wide peripheral blood leukocyte DNA methylation microarrays identified a single association with inflammatory bowel diseases

BACKGROUND

Crohn's disease (CD) and ulcerative colitis (UC) are common forms of inflammatory bowel disease (IBD). Monozygotic (MZ) twin discordance rates and epidemiologic data implicate that environmental changes and epigenetic factors may play a pathogenic role in IBD. DNA methylation (the methylation of cytosines within CpG dinucleotides) is an epigenetic modification, which can respond to environmental influences. We investigated whether DNA methylation might be connected with IBD in peripheral blood leukocyte (PBL) DNA by utilizing genome-wide microarrays.

METHODS

Two different high-throughput microarray-based methods for genome-wide DNA methylation analysis were employed. First, DNA isolated from MZ twin pairs concordant (CD: 4; UC: 3) and discordant (CD: 4; UC: 7) for IBD was interrogated by a custom-made methylation-specific amplification microarray (MSAM). Second, the recently developed Illumina Infinium HumanMethylation450 BeadChip arrays were used on 48 samples of PBL DNA from discordant MZ twin pairs (CD: 3; UC: 3) and treatment-naive pediatric cases of IBD (CD: 14; UC: 8), as well as controls (n = 14). The microarrays were validated with bisulfite pyrosequencing.

RESULTS

The MSAMs did not yield significant IBD associations. The Methylation BeadChip approach identified a single DNA methylation association of IBD at TEPP (testis, prostate and placenta-expressed protein) when DNA isolated selectively from peripheral blood mononuclear cells was analyzed (8.6% increase in methylation between CD and control, FDR = 0.0065).

CONCLUSIONS

Microarray interrogation of IBD-dependent DNA methylation from PBLs appears to have limited ability to detect significant disease associations. More detailed and/or selective approaches may be useful for the elucidation of connections between the DNA methylome and IBD in the future.