Endoscopic Versus Histological Disease Extent at Presentation of Paediatric Inflammatory Bowel Disease

MR Enterography Scores Correlate with Degree of Mucosal Healing in Pediatric Crohn's Disease: A Pilot Study

Objectives

MR enterography (MRE) Index of Activity (MaRIA) and Clermont are validated scores that correlate with Crohn's disease (CD) activity; however, the Clermont score has not been validated to correlate with the degree of change in mucosal inflammation post induction treatment in children. This pilot study evaluated if MaRIA and Clermont scores can serve as surrogates to ileocolonoscopy for assessing interval change in mucosal inflammation in pediatric CD post-induction treatment.

Methods

Children with known or newly diagnosed ileocolonic CD starting or changing therapy underwent ileocolonoscopy, scored with simple endoscopic score for Crohn's disease (SES-CD), and MRE on the same day at two time points (Week 0 and 12). Accuracy of global MaRIA and Clermont indices relative to ileocolonoscopy in detecting degree of post-treatment interval change in mucosal inflammation was assessed through correlational coefficients (r). Inter-reader agreement was calculated for imaging scores through intraclass correlation (ICC).

Results

Sixteen children (mean age 11.5 ± 2.8) were evaluated. Global MaRIA/Clermont correlated with SES-CD in detecting the degree of change in mucosal inflammation (r = 0.676 and r = 0.677, P < 0.005, respectively). Correlation for pooled timepoint assessments between SES-CD and global MaRIA/Clermont was moderate (r = 0.546, P < 0.001 and r = 0.582, P < 0.001, respectively). Inter-rater reliability for global MaRIA and Clermont was good (ICC = 0.809 and ICC = 0.768, respectively, P < 0.001).

Conclusions

MRE-based global scores correlate with endoscopic indices and may be used to monitor disease changes in children with CD undergoing induction treatment, which can advise the physician if treatment changes should be made.

Frequency and clinical significance of histologic upper gastrointestinal tract findings in children with inflammatory bowel disease

OBJECTIVE

Assessment of the upper gastrointestinal tract (UGI) may enable more personalized treatment strategies in pediatric inflammatory bowel disease (IBD). However, data on the frequency and significance of these findings remain limited.

METHODS

Data on 132 pediatric IBD patients with systematic UGI sampling were collected and the baseline characteristics and presence of complications compared between those with and without histological UGI findings. The control group comprised 162 children who received no diagnoses.

RESULTS

Seventy-six children had ulcerative colitis (UC), 47 Crohn's disease (CD) and nine IBD unclassified. UGI findings were more common in IBD patients than controls (69.7% vs. 30.9%, respectively, p < .001), particularly in the stomach (62.1% vs. 16.8%; p < .001). Among IBD patients, findings were more common in CD than in UC (80.9% vs. 63.2%; p = .038), particularly in the duodenum (21.3% vs. 2.6%, p = .001). Four patients had UGI granulomas consistent with CD. Hypoalbuminemia (OR 3.22; 95% CI 1.18-8.79) and failure to thrive (2.82; 1.17-6.78) increased the likelihood of UGI findings in IBD. In CD, perianal morbidity was less common in those with than in those without UGI findings (13.2% vs. 44.4%; p = .032) whereas in UC, UGI findings increased the risk for co-morbidities (18.8% vs. 3.6%; p = .059). The long-term outcomes did not differ between patients with or without UGI findings.

CONCLUSIONS

Histologic UGI findings were more common in children with IBD than in children with no gastrointestinal diagnoses. In CD, UGI findings were more frequent than in UC, especially in the duodenum. In UC, UGI findings were associated with more complex disease.

Temporal trends in ileoanal pouch surgery for paediatric onset ulcerative colitis in England from 1997 to 2015 using hospital episode statistics

INTRODUCTION

Ileal pouch-anal anastomosis (IPAA) following colectomy for ulcerative colitis (UC) achieves restoration of intestinal continuity with potential return of continence. It is undertaken relatively infrequently in children. We aimed to investigate the national frequency of IPAA in paediatric UC and report outcomes useful for surgeon/centre benchmarking.

METHODS

Hospital Episode Statistics data were obtained for all admissions in England (1997-2015) in children (< 18 years) who underwent IPAA for UC using OPCS-4 procedural codes. Surgeon specialty, readmission, and reoperation rates were identified. Data are median (interquartile range).

RESULTS

UC was diagnosed in 7604 children in whom 346 (4.6%) underwent IPAA at age 15 [13-17] years. Laparoscopy was used in 55 (15.9%) cases and in the most recent 10 years more commonly by specialist paediatric surgeons (SPS) than general surgeons (GS) (34.3%vs14.7%, p = 0.001). National frequency of IPAA ranged from 12 to 34 annually. Where specialty was available, 95/342 (57%) cases were undertaken by GS and 147/342 (43%) cases by SPS. The proportion of cases undertaken by SPS increased significantly compared to GS over the study period, p = 0.0003. Post-operative length of stay was 8 [6-11] days. During the index admission, unplanned return to theatre was required in 25/346 (7.2%). Following discharge 58 (16.8%) were readmitted within 30 days. Overall return to theatre rate within 30 days of pouch surgery was 11.0% (38/346).

CONCLUSION

IPAA for UC within childhood is undertaken infrequently in England, with a shift towards SPS undertaking surgery. These data can be used by surgeons to benchmark outcomes.

LEVEL OF EVIDENCE

IV.

Upper gastrointestinal tract involvement of Crohn disease: clinical implications in children and adolescents

Crohn disease (CD) is a multifactorial inflammatory disorder that can affect all segments of the gastrointestinal (GI) tract but typically involves the ileum and/or colon. To assess patient prognosis and choose appropriate treatment, it is necessary to accurately evaluate the factors influencing poor outcomes, including disease phenotype. Pediatric CD involving the upper GI (UGI) tract has become increasingly recognized with the introduction of routine upper endoscopy with biopsies for all patients and the increased availability of accurate small bowel evaluations. Most clinical manifestations are mild and nonspecific; however, UGI involvement should not be overlooked since it can cause serious complications. Although controversy persists about the definition of upper GI involvement, aphthoid ulcers, longitudinal ulcers, a bamboo jointlike appearance, stenosis, and fistula are endoscopic findings suggestive of CD. In addition, the primary histological findings, such as focally enhanced gastritis and noncaseating granulomas, are highly suggestive of CD. The association between UGI involvement and poor prognosis of CD remains controversial. However, the unstandardized definition and absence of a validated tool for evaluating disease severity complicate the objective assessment of UGI involvement in CD. Therefore, more prospective studies are needed to provide further insight into the standardized assessment of UGI involvement and longterm prognosis of CD. Our review summarizes the findings to date in the literature as well as UGI involvement in CD and its clinical implications.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

Limited clinical significance of tissue calprotectin levels in bowel mucosa for the prediction of complicated course of the disease in children with ulcerative colitis

BACKGROUND

Fecal calprotectin (F-CPT) represents one of the most widely used biomarkers for intestinal inflammation. However, the levels may be false negative or false positive in some situations.

AIMS

To evaluate the usefulness of immunohistochemical (IHC) detection of tissue calprotectin (T-CPT) in bowel mucosa in children with ulcerative colitis (UC). We focused at correlation of T-CPT with levels of F-CPT and endoscopic and microscopic disease activity at the time of diagnosis and tested whether T-CPT could serve as predictor of complicated course of the disease.

METHODS

Forty-nine children with newly diagnosed UC between 6/2010-1/2018 entered the study. Endoscopic activity was objectified using the Ulcerative Colitis Endoscopic Index of Severity (UCEIS), clinical activity by Pediatric Ulcerative Colitis Activity Index (PUCAI) and microscopic activity by Geboes and Nancy score. The IHC staining for CPT antigen was performed on bioptic samples from 6 bowel segments and the number of CPT + cells were counted per 1HPF. During the minimal follow-up of 12 months we searched for presence of complications. As outcome for Cox regression model we used composite endpoints: A) Acute Severe Colitis, colectomy, anti-TNF treatment; B) systemic corticotherapy; C) systemic 5-aminosalicylic acid therapy.

RESULTS

Neither levels of T-CPT nor values of UCEIS, Geboes or Nancy score predicted the given complications. We found F-CPT levels (HR 2.42 and 2.52) and PUCAI > 40 points (HR 2.98) as predictors of time to endpoints B and C. Good correlation was found between T-CPT levels and Geboes score (k = 0.65) and Nancy score (k = 0.62) and modest with F-CPT (k = 0.44), UCEIS (k = 0.38) and PUCAI (k = 0.42).

CONCLUSIONS

T-CPT correlated well with microscopic scores. F-CPT and PUCAI appear to be better predictors of unfavorable outcome in patients with UC.

Review article: the genetics of the human leucocyte antigen region in inflammatory bowel disease

BACKGROUND

The human leucocyte antigen (HLA) complex, located at chromosome 6p21.3 is a highly polymorphic region containing the classical class I and II HLA genes. The region is highly associated with inflammatory bowel disease (IBD), largely through genome-wide association studies (GWAS).

AIMS

To review the role of HLA in immune function, summarise data on risk/protective HLA genotypes for IBD, discuss the role of HLA in IBD pathogenesis, treatment and examine limitations that might be addressed by future research.

METHODS

An organised search strategy was used to collate articles describing HLA genes in IBD, including Crohn's disease and ulcerative colitis.

RESULTS

All classical HLA genes with variation (including HLA-A, B, C, DRB1, DQA1, DQB1, DPA1 and DPB1) harbour IBD-associated genotypes. The most implicated gene is HLA-DRB1, with HLA-DRB1*03:01 the most associated risk allele in both Crohn's disease and ulcerative colitis. Elucidating precise disease associations is challenging due to high linkage disequilibrium between HLA genotypes. The mechanisms by which risk alleles cause disease are multifactorial, with the best evidence indicating structural and electrostatic alteration impacting antigen binding and downstream signalling. Adverse medication events have been associated with HLA genotypes including with thiopurines (pancreatitis) and anti-TNF agents (antibody formation).

CONCLUSIONS

The HLA complex is associated with multiple risk/protective alleles for IBD. Future research utilising long-read technology, ascertainment of zygosity and integration in disease modelling will improve the functional understanding and clinical translation of genetic findings.

Endoscopic and Histological Assessment of Paediatric Inflammatory Bowel Disease Over a 3-Year Follow-up Period

OBJECTIVES

Discrepancies between inflammatory bowel disease (IBD) endoscopic/histological extent are documented at diagnosis. It is unclear whether these differences persist through disease course, with potential impact on categorization and management. We aimed to analyze the progression of disease over a 3-year period.

METHODS

Patients younger than 17 years, diagnosed between 2010 and 2013 at Southampton Children's Hospital and followed-up for 3 years were eligible. Primary outcome was disease extent at diagnosis and follow-up. Data are presented as percentage of patients undergoing endoscopy. Paris classification (PC) and PC using histological, rather than endoscopic disease, were determined.

RESULTS

One hundred and twenty-five patients were included, 66 boys; Crohn's disease (CD) 74, ulcerative colitis (UC) 40, IBD unclassified (IBDU) 11. All had endoscopy at diagnosis. One hundred and two patients underwent ≥1 repeat endoscopies.Disease extent reduced from diagnosis to first follow-up endoscopy for both endoscopic and histological disease extent (CD/UC/IBDU, all P < 0.00006). Histological extent remained greater than endoscopic in CD with significant differences in stomach, ileum, and large bowel at all follow-up points (P =  < 0.045). Endoscopic matched histological extent in UC/IBDU. Applying a modified PC resulted in significant changes for CD (L3 27.4%-53.2%, P = 0.006, L3 + L4A 21%-50%, P = 0.001, and upper gastrointestinal disease 50%-80.6%, P = 0.0006) but not UC. CD height (-0.37 to -0.25) and weight (-1.09 to -0.19) standard deviation scores increased from diagnosis to follow-up.

CONCLUSIONS

Histological disease is greater than endoscopic extent at diagnosis and during follow-up in CD, although not in UC/IBDU. Classification of disease extent in CD should be based on both endoscopic and histological criteria.

Classification of Paediatric Inflammatory Bowel Disease using Machine Learning

Paediatric inflammatory bowel disease (PIBD), comprising Crohn's disease (CD), ulcerative colitis (UC) and inflammatory bowel disease unclassified (IBDU) is a complex and multifactorial condition with increasing incidence. An accurate diagnosis of PIBD is necessary for a prompt and effective treatment. This study utilises machine learning (ML) to classify disease using endoscopic and histological data for 287 children diagnosed with PIBD. Data were used to develop, train, test and validate a ML model to classify disease subtype. Unsupervised models revealed overlap of CD/UC with broad clustering but no clear subtype delineation, whereas hierarchical clustering identified four novel subgroups characterised by differing colonic involvement. Three supervised ML models were developed utilising endoscopic data only, histological only and combined endoscopic/histological data yielding classification accuracy of 71.0%, 76.9% and 82.7% respectively. The optimal combined model was tested on a statistically independent cohort of 48 PIBD patients from the same clinic, accurately classifying 83.3% of patients. This study employs mathematical modelling of endoscopic and histological data to aid diagnostic accuracy. While unsupervised modelling categorises patients into four subgroups, supervised approaches confirm the need of both endoscopic and histological evidence for an accurate diagnosis. Overall, this paper provides a blueprint for ML use with clinical data.

Fecal HMGB1 Reveals Microscopic Inflammation in Adult and Pediatric Patients with Inflammatory Bowel Disease in Clinical and Endoscopic Remission

BACKGROUND

Fecal high mobility group box 1 (HMGB1) has been suggested to be a novel noninvasive biomarker of gut inflammation. We aimed to assess the reliability of fecal HMGB1, compared with fecal calprotectin (FC), in detecting intestinal inflammation in pediatric and adult patients with inflammatory bowel disease (IBD) and to evaluate the accuracy of HMGB1 in identifying patients with IBD in clinical and endoscopic remission who still have histologic features of inflammation.

METHODS

Stool samples from 85 children with IBD (49 Crohn's disease [CD] and 36 ulcerative colitis [UC] and 119 adults [57 Crohn's disease and 62 ulcerative colitis]) were analyzed for the study. Age-matched healthy subjects were used as controls. Fecal HMGB1 and fecal calprotectin were detected through western blot and ELISA, respectively.

RESULTS

Fecal HMGB1 expression was significantly increased in pediatric and adult patients with Crohn's disease and ulcerative colitis and strongly correlated with the disease severity. Fecal calprotectin and HMGB1 significantly correlated in pediatric (r: 0.60, P < 0.001) and adult (r: 0.72, P < 0.001) IBD patients. Moreover, in patients with clinical and endoscopic remission only fecal HMGB1 showed a strong match with the degree of histological scores of inflammation (CGHAS/IGHAS for Crohn's disease and Geboes Score for ulcerative colitis).

CONCLUSIONS

Fecal HMGB1 is confirmed to be a reliable biomarker of intestinal inflammation; indeed, it significantly correlates with fecal calprotectin in pediatric and adult IBD patients. Moreover, only fecal HMGB1 identifies histologic inflammation in subjects with IBD in clinical and endoscopic remission.