Differentiating ulcerative colitis from Crohn disease in children and young adults: report of a working group of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the Crohn's and Colitis Foundation of America

Validation of the Padova Prognostic Score for Colitis in Predicting Long-Term Outcome After Restorative Proctocolectomy

BACKGROUND

In 10%-20% of cases it is impossible to make a differential diagnosis between ulcerative colitis and Crohn's colitis. A 50% failure rate of J pouch ilea-anal anastomosis is observed in Crohn's colitis. In 2009, we created the Padua Prognostic Score for Colitis (PPSC) to predict the long-term clinical and functional outcome and quality of life of patients undergoing restorative proctocolectomy with J pouch. The aim of the present study is to establish and validate the accuracy of a prognostic score for chronic inflammatory bowel diseases (IBD).

PATIENT POPULATION AND METHODS

The PPSC was created in 2009 by integrating clinical and histological information of patients undergoing RPC. It included preoperative perianal abscess or fistula, rectal sparing, terminal ileum involvement, skip lesions and histological diagnosis of indeterminate colitis or Crohn's colitis on the operative specimen. The validity of this score was tested in predicting postoperative abscess or fistula, anal canal disease, pouchitis, pouch failure and new diagnosis of Crohn's disease. Correlation analysis, ROC curve analysis and survival analysis were used to validate the PPSC in a different cohort from the previous one.

RESULTS

We retrospectively enrolled in this study 138 consecutive patients undergoing CPR for ulcerative colitis (n = 127) or indeterminate colitis (n = 11) in our institution since 2005 to 2020. In this period, we observed 11 patients with postoperative abscess or fistula, 3 with anal canal disease, 40 with pouchitis, 6 with pouch failure and 6 with new diagnosis of Crohn's disease. In the new validation cohort, the PPSC confirmed to have a good accuracy in predicting the onset of postoperative CD (AUC = 74.5%, p = 0.018). Kaplan Meier curves demonstrate how a PPSC over 1 can reliably predicts the long-term onset of, pouchitis (p = 0.002) and anal abscess or fistulae (p = 0.04).

CONCLUSIONS

In this validation study we confirmed the accuracy of the PPSC in predicting postoperative fistulas or abscesses and pouchitis. Therefore, we believe that in clinical practice patients with a PPSC score greater than 1 should be warned of this risk of possible Crohn's disease diagnosis and pouch failure.

Linear Growth Impairment in Patients With Pediatric Inflammatory Bowel Disease

Introduction Linear growth impairment (LGI) is one of the complications of pediatric inflammatory bowel disease (IBD). This study aimed to assess the linear growth of patients with pediatric IBD and to detect the frequency and the possible risk factors of LGI. Methods A retrospective cross-sectional review of medical records of patients with pediatric IBD was conducted in the pediatrics department, Salmaniya Medical Complex, Bahrain, from 1984 to 2019. Demographic and anthropometric data were gathered. World Health Organization (WHO) standards and references were used to define LGI. According to WHO, stunting and severe stunting were defined as length/height for age of <-2 standard deviations and <-3 standard deviations from age and sex-specific reference means, respectively. To determine the possible risk factors for LGI, stunted patients were compared with normal height patients in regard to demographic data, clinical presentations, and treatment used. Results Out of 130 patients with pediatric IBD, 88 (67.7%) had anthropometric data available. Fifty-five (62.5%) were males. Forty-seven (53.4%) had Crohn's disease and 41 (46.6%) had ulcerative colitis. The mean age at presentation was 10.7±3.8 years. The median age at the time of growth measurement was 14.2 (interquartile range=12.1-24.4) years. Fifteen (17%) patients were stunted, and seven (46.7%) of those stunted patients were severely stunted. Weight at presentation was lower in stunted patients (21.6±5.9 kilograms) compared to normal height patients (31±13.4 kilogram) (p=0.048). Sex, delivery type, birth weight, height at presentation, age at presentation, age at growth measurements, IBD type, disease duration, presence of extraintestinal manifestations, and prednisolone and biologic therapy use were not significant factors of stunting. Conclusion Patients with pediatric IBD have a high prevalence of LGI compared to the general population. Low weight at disease presentation is the only significant risk factor for LGI. This might indicate that IBD as a disease by itself is having the main negative impact on linear growth.

Pathophysiological Concepts and Management of Pulmonary Manifestation of Pediatric Inflammatory Bowel Disease

Pulmonary manifestation (PM) of inflammatory bowel disease (IBD) in children is a rare condition. The exact pathogenesis is still unclear, but several explanatory concepts were postulated and several case reports in children were published. We performed a systematic Medline search between April 1976 and April 2022. Different pathophysiological concepts were identified, including the shared embryological origin, "miss-homing" of intestinal based neutrophils and T lymphocytes, inflammatory triggering via certain molecules (tripeptide proline-glycine-proline, interleukin 25), genetic factors and alterations in the microbiome. Most pediatric IBD patients with PM are asymptomatic, but can show alterations in pulmonary function tests and breathing tests. In children, the pulmonary parenchyma is more affected than the airways, leading histologically mainly to organizing pneumonia. Medication-associated lung injury has to be considered in pulmonary symptomatic pediatric IBD patients treated with certain agents (i.e., mesalamine, sulfasalazine or infliximab). Furthermore, the risk of pulmonary embolism is generally increased in pediatric IBD patients. The initial treatment of PM is based on corticosteroids, either inhaled for the larger airways or systemic for smaller airways and parenchymal disease. In summary, this review article summarizes the current knowledge about PM in pediatric IBD patients, focusing on pathophysiological and clinical aspects.

Pediatric Management of Crohn's Disease

Pediatric Crohn's disease is often more severe, requires higher levels of immunosuppression, and is associated with greater morbidity compared with adult Crohn's disease. Unique considerations in pediatric Crohn's disease include growth impairment, pubertal delay, bone disease, longevity of disease burden, and psychosocial impact. Treatment options are limited, requiring off-label use of therapy in this challenging patient population. Understanding the medications available, the existing evidence supporting their use, and side effects is important. There is tremendous potential for growth and improvement in this field and it is essential that all gastroenterologists have an understanding of this complex and unique patient population.

Wasting condition as a marker for severe disease in pediatric Crohn's disease

Several studies have shown an association between sarcopenia and clinical outcomes in patients with Crohn's disease (CD). However, studies have shown different results, and the association between prognosis and wasting conditions in pediatric patients with CD is uncertain. In this study, we evaluated the clinical significance of wasting in pediatric CD patients.We retrospectively analyzed data on wasting syndrome in patients diagnosed with CD at the Pediatric Department of Gachon University Gil Medical Center between January 1995 and January 2018.Of 105 patients diagnosed with CD, 39.0% were classified into the wasting group (weight-for-age z-score ≤-1) and 61.0% into the nonwasting group (weight-for-age z-score >-1). Height-for-age and body mass index-for-age z-scores at the time of diagnosis were significantly associated with wasting (P < .001 and P < .001, respectively). Additionally, wasting was significantly associated with low levels of hemoglobin (P < .001), high levels of inflammatory markers, including C-reactive protein (P = .005) and erythrocyte sedimentation rate (P = .04), and a smaller surface area of the gluteus maximus muscle (P < .001). Interestingly, since the site of CD involvement and other markers for nutrition did not correlate with wasting syndrome, wasting appears to be a marker for the severity of pediatric CD. Lastly, the wasting group tended to have a greater use of biologic therapy after first-line therapy failed to improve wasting syndrome.Wasting syndrome, including sarcopenia, can serve as a marker for the severity of pediatric CD.

Evaluating Eosinophilic Colitis as a Unique Disease Using Colonic Molecular Profiles: A Multi-Site Study

BACKGROUND & AIMS

Colonic eosinophilia, an enigmatic finding often referred to as eosinophilic colitis (EoC), is a poorly understood condition. Whether EoC is a distinct disease or a colonic manifestation of eosinophilic gastrointestinal diseases (EGIDs) or inflammatory bowel disease (IBD) is undetermined.

METHODS

Subjects with EoC (n = 27) and controls (normal [NL, n = 20], Crohn's disease [CD, n = 14]) were enrolled across sites associated with the Consortium of Eosinophilic Gastrointestinal Disease Researchers. EoC was diagnosed as colonic eosinophilia (ascending ≥100, descending ≥85, sigmoid ≥65 eosinophils/high-power field) with related symptoms. Colon biopsies were subjected to RNA sequencing. Associations between gene expression and histologic features were analyzed with Spearman correlation; operational pathways and cellular constituents were computationally derived.

RESULTS

We identified 987 differentially expressed genes (EoC transcriptome) between EoC and NL (>1.5-fold change, P < .05). Colonic eosinophil count correlated with 31% of EoC transcriptome, most notably with CCL11 and CLC (r = 0.78 and 0.77, P < .0001). Among EoC and other EGIDs, there was minimal transcriptomic overlap and minimal evidence of a strong allergic type 2 immune response in EoC compared with other EGIDs. Decreased cell cycle and increased apoptosis in EoC compared with NL were identified by functional enrichment analysis and immunostaining using Ki-67 and cleaved caspase-3. Pericryptal circumferential eosinophil collars were associated with the EoC transcriptome (P < .001). EoC transcriptome-based scores were reversible with disease remission and differentiated EoC from IBD, even after controlling for colonic eosinophil levels (P < .0001).

CONCLUSIONS

We established EoC transcriptomic profiles, identified mechanistic pathways, and integrated findings with parallel IBD and EGID data. These findings establish EoC as a distinct disease compared with other EGIDs and IBD, thereby providing a basis for improving diagnosis and treatment.

Simplified Magnetic Resonance Index of Activity Is Useful for Terminal Ileal but not Colonic Disease in Pediatric Crohn Disease

BACKGROUND

Ileocolonoscopy (IC) detects mucosal inflammation and magnetic resonance enterography (MRE) detects transmural inflammation in Crohn disease (CD). We aimed to evaluate the relationship between the simplified magnetic resonance index of activity (MARIAs) and measures of inflammation by IC in children with newly diagnosed CD.

METHODS

Retrospective review of 140 patients 6-18 years of age with CD who had baseline IC and MRE within 5 weeks of diagnosis. MARIAs was calculated for each intestinal segment (terminal ileum [TI], ascending colon, transverse colon, descending colon, sigmoid colon, rectum), defined as (1 × thickness > 3 mm) + (1 × edema) + (1 × fat stranding) + (2 × ulcers). Sensitivity and specificity were derived using receiver operating characteristic (ROC) curves to compare MARIAs to IC findings.

RESULTS

Using IC as the reference standard, the cutoff MARIAs ≥1 identified TI segments with active inflammation with 84% sensitivity, 73% specificity, 85% positive predictive value (PPV), 70% negative predictive value (NPV), and area under the curve (AUC) 0.782 (95% confidence interval [CI] 0.689-0.876). The cutoff MARIAs ≥2 identified TI segments with severe lesions with 87% sensitivity, 76% specificity, 87% PPV, 76% NPV, and AUC 0.814 (95% CI 0.712-0.916). There was poor sensitivity for all colonic segments.

CONCLUSION

The MARIAs is feasible and accurate in reflecting disease activity in the TI, but not in the colon, in children with newly diagnosed CD. Although the MARIAs may be useful for monitoring TI disease activity over time, full assessment continues to require both IC and MRE.

Inflammatory Bowel Disease: Clinical Diagnosis and Surgical Treatment-Overview

This article is an overview of guidelines for the clinical diagnosis and surgical treatment of predominantly colonic inflammatory bowel diseases (IBD). This overview describes the systematically and comprehensively multidisciplinary recommendations based on the updated principles of evidence-based literature to promote the adoption of best surgical practices and research as well as patient and specialized healthcare provider education. Colonic IBD represents idiopathic, chronic, inflammatory disorders encompassing Crohn's colitis (CC) and ulcerative colitis (UC), the two unsolved medical subtypes of this condition, which present similarity in their clinical and histopathological characteristics. The standard state-of-the-art classification diagnostic steps are disease evaluation and assessment according to the Montreal classification to enable explicit communication with professionals. The signs and symptoms on first presentation are mainly connected with the anatomical localization and severity of the disease and less with the resulting diagnosis "CC" or "UC". This can clinically and histologically be non-definitive to interpret to establish criteria and is classified as indeterminate colitis (IC). Conservative surgical intervention varies depending on the disease phenotype and accessible avenues. The World Gastroenterology Organizations has, for this reason, recommended guidelines for clinical diagnosis and management. Surgical intervention is indicated when conservative treatment is ineffective (refractory), during intractable gastrointestinal hemorrhage, in obstructive gastrointestinal luminal stenosis (due to fibrotic scar tissue), or in the case of abscesses, peritonitis, or complicated fistula formation. The risk of colitis-associated colorectal cancer is realizable in IBD patients before and after restorative proctocolectomy with ileal pouch-anal anastomosis. Therefore, endoscopic surveillance strategies, aimed at the early detection of dysplasia, are recommended. During the COVID-19 pandemic, IBD patients continued to be admitted for IBD-related surgical interventions. Virtual and phone call follow-ups reinforcing the continuity of care are recommended. There is a need for special guidelines that explore solutions to the groundwork gap in terms of access limitations to IBD care in developing countries, and the irregular representation of socioeconomic stratification needs a strategic plan for how to address this serious emerging challenge in the global pandemic.

Clinical Phenotypes and Outcomes in Monogenic Versus Non-monogenic Very Early Onset Inflammatory Bowel Disease

BACKGROUND AND AIMS

Over 80 monogenic causes of very early onset inflammatory bowel disease [VEOIBD] have been identified. Prior reports of the natural history of VEOIBD have not considered monogenic disease status. The objective of this study is to describe clinical phenotypes and outcomes in a large single-centre cohort of patients with VEOIBD and universal access to whole exome sequencing [WES].

METHODS

Patients receiving IBD care at a single centre were prospectively enrolled in a longitudinal data repository starting in 2012. WES was offered with enrollment. Enrolled patients were filtered by age of diagnosis <6 years to comprise a VEOIBD cohort. Monogenic disease was identified by filtering proband variants for rare, loss-of-function, or missense variants in known VEOIBD genes inherited according to standard Mendelian inheritance patterns.

RESULTS

This analysis included 216 VEOIBD patients, followed for a median of 5.8 years. Seventeen patients [7.9%] had monogenic disease. Patients with monogenic IBD were younger at diagnosis and were more likely to have Crohn's disease phenotype with higher rates of stricturing and penetrating disease and extraintestinal manifestations. Patients with monogenic disease were also more likely to experience outcomes of intensive care unit [ICU] hospitalisation, gastrostomy tube, total parenteral nutrition use, stunting at 3-year follow-up, haematopoietic stem cell transplant, and death. A total of 41 patients [19.0%] had infantile-onset disease. After controlling for monogenic disease, patients with infantile-onset IBD did not have increased risk for most severity outcomes.

CONCLUSIONS

Monogenic disease is an important driver of disease severity in VEOIBD. WES is a valuable tool in prognostication and management of VEOIBD.

Solitary Rectal Ulcer Syndrome Mimicking Perianal Crohn's Disease

Solitary rectal ulcer syndrome (SRUS) is an uncommon condition that presents with non-specific symptoms shared by other disease processes. This case report shares a unique presentation in which a patient was thought to have fistulous perianal Crohn's disease then underwent treatment with infliximab but was ultimately found to have SRUS. The prognosis and treatment of SRUS vary greatly from inflammatory bowel disease. Making the correct diagnosis is imperative when considering Crohn's disease and its mimickers. 

Histopathology of intestinal villi in neonatal and paediatric age: main features with clinical correlation - Part II

In this paper, we will continue the description of histological findings of infantile and paediatric small bowel alterations with the main clinical pictures and differential diagnosis. We emphasise once again the need to evaluate the biopsies in an adequate clinical contest and with a systematic approach, including epithelial alterations, lamina propria changes, mucosal architecture, and the distribution of inflammation, together with other morphological signs more specific of certain diseases. We describe the histological findings of coeliac and Crohn's disease, gastrointestinal food allergic diseases, Langerhans cell histiocytosis, nutritional deficiencies and infections. Finally, we suggest the principal issues in the drafting the pathological report for appropriate interpretation and usefulness in clinical practice.

Histologic Diagnosis of Inflammatory Bowel Diseases

Inflammatory bowel disease, including ulcerative colitis and Crohn disease, is an idiopathic chronic inflammatory condition of the gastrointestinal tract. Since neither the clinical manifestations nor the morphologic features of inflammatory bowel disease are pathognomonic alone, the differential diagnosis to consider is relatively broad, and it relies on the synthesis of clinical, endoscopic, and microscopic features. Long-held histologic diagnostic principles include recognizing structural and inflammatory features of chronicity, that is, architectural distortion, basal plasmacytosis, and expansion of the lamina propria lymphoplasmacytic infiltrate. In addition, evaluation of the neutrophilic inflammation and related crypt and epithelial destruction is essential to gauge the activity of the disease. Nevertheless, these features can be difficult to confirm in special settings, including at the inception of the disease or in partially treated cases. This review will explore the classic morphologic features of ulcerative colitis and Crohn disease, followed by a detailed discussion of atypical and diagnostically challenging presentations and a brief review of the clinical aspects necessary for the daily practice of pathologists.

Upper Gastrointestinal Tract Involvement in Inflammatory Bowel Diseases: Histologic Clues and Pitfalls

The upper gastrointestinal (UGI) manifestations of inflammatory bowel diseases (IBDs) are frequently obscured by classic ileal and colonic symptoms and are reported to involve only 0.5% to 4% of adult patients. However, because of the improvement of endoscopic techniques and the growing use of esophagogastroduodenososcopy with biopsy, both asymptomatic and clinically significant esophageal, gastric, and duodenal manifestations are increasingly recognized. The UGI involvement in IBD was historically synonymous with Crohn's disease (CD), but the doctrine of ulcerative colitis (UC) being limited to the colon has been challenged, and UC-related gastroduodenal lesions have been reported. The diagnosis of UGI IBD should ideally rely on a combination of the clinical history, endoscopic picture, and histologic features. Although endoscopic changes such as aphthoid or longitudinal ulcers and bamboo-joint-like pattern are suggestive of CD, histologic evaluation increases the sensitivity of the IBD diagnosis since histologic alterations may be present in endoscopically unremarkable mucosa. Conversely, in many cases, the histologic findings are nonspecific, and the knowledge of clinical history is vital for reaching an accurate diagnosis. The presence of epithelioid granuloma is highly suggestive of CD but is present in a minority of CD cases; thus, pathologists should be aware of how to diagnose UGI IBD in the absence of granulomata. This article reviews the most important clinical, endoscopic, and histologic features of IBD-associated esophagitis, gastritis, and duodenitis, as well as the IBD-related manifestations in the biliary tract and the postcolectomy setting.

Precision Medicine in Pediatric Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) describes a heterogenous group of diseases characterized by chronic inflammation of the intestinal tract. The IBD subtypes, Crohn's disease, ulcerative colitis, and IBD-Unspecified, each have characteristic features, but heterogeneity remains even among the subtypes. There has been an explosion of new knowledge on the possible pathogenesis of IBD over the last 2 decades mirroring innovation and refinement in technology, particularly the generation of large scale - "-omic" data. This knowledge has fostered a veritable renaissance of novel diagnostics, prognostics, and therapeutics, with patients with IBD seeing hope bloom in the increasingly large armamentarium of IBD therapies. However, while there are increased numbers of therapies and more pathways being targeted, the number of medications for IBD is still finite and the efficacy has reached a plateau. Precision medicine (PM) is much needed to rationally select and optimize IBD therapies in the new reality of wider but still limited choice with a concurrent, increasingly fine resolution on the significance and utility of clinical, genetic, microbial, and proteomic characteristics that define individual patients. PM is a rapidly changing art, but this review will strive to detail the current state and future directions of PM in pediatric IBD.

Paediatric Ulcerative Colitis Is a Fibrotic Disease and Is Linked with Chronicity of Inflammation

BACKGROUND AND AIMS

Intestinal fibrosis has recently been characterised in adult ulcerative colitis and may affect motility, diarrhoea, and the symptom of urgency. We aimed to charactersze the presence of fibrosis in paediatric patients with ulcerative colitis, and its link to severity and chronicity of mucosal inflammation, as well as clinical factors of severity.

METHODS

We performed a single-centre cross-sectional study in children ages 1-18 years with ulcerative colitis, undergoing colectomy or proctocolectomy. Tissue cross-sections were derived from proximal, mid, and distal colon and rectum, and inflammation and fibrosis were graded based on previously developed scores. Clinical data were collected prospectively.

RESULTS

From 62 patients, 205 intestinal sections were evaluated. Median age at diagnosis was 13 years, 100% had extensive colitis, and all resections were done for refractory disease. The presence, chronicity, and degree of inflammation were linked with the presence of fibrosis. Thickness of the muscularis mucosa was also linked with presence and chronicity of inflammation. The overall submucosal fibrosis burden was associated with prior anti-tumour necrosis factor use.

CONCLUSIONS

Paediatric patients with ulcerative colitis exhibit colorectal submucosal fibrosis and muscularis mucosa thickening, which correlate with the presence, chronicity, and degree of mucosal inflammation. Fibrosis should be recognised as a complication of paediatric ulcerative colitis, and ulcerative colitis should be considered a progressive disease.

Safety of Venous Thromboprophylaxis With Low-molecular-weight Heparin in Children With Ulcerative Colitis

OBJECTIVES

To evaluate for increased rectal bleeding following enoxaparin thromboprophylaxis in children hospitalized for ulcerative colitis (UC).

METHODS

Retrospective cohort study (2007--2016) of 218 inpatients with active UC. Patients receiving enoxaparin were compared with a nonenoxaparin-treated patient group. Severity of UC was determined using the Pediatric Ulcerative Colitis Activity Index (PUCAI). Hemoglobin (Hb) values and packed red blood cell (pRBC) transfusions were reviewed for a 7-day period following hospital admission. A linear mixed effect model was used to compare change in Hb values between the groups. Risk of pRBC transfusion was compared using a log-rank test and Cox proportional hazard regression. A sub-analysis was also conducted restricting to patients with severe UC to provide more generalizable insight into safety profile of enoxaparin.

RESULTS

Children hospitalized for UC and receiving enoxaparin were more likely to have severe disease, received infliximab therapy and be admitted after 2010. Use of enoxaparin showed there was not a difference (P = 0.60) in the fall of Hb detected among those with acute severe colitis (initial PUCAI ≥65) during the week following admission. Moreover, there was no difference in the risk of requiring a pRBC transfusion with enoxaparin use (log-rank test all patients: P = 0.80; severe UC: P = 0.88; Cox proportional hazard regression all patients: P = 0.72; severe UC: 0.85).

CONCLUSIONS

There was no difference in Hb levels or need for blood transfusions in children hospitalized for severe UC (PUCAI ≥65) whether or not they received enoxaparin for thromboembolism prophylaxis.

Elevated colonic microbiota-associated paucimannosidic and truncated N-glycans in pediatric ulcerative colitis

Pediatric ulcerative colitis (UC) is a distinct type of inflammatory bowel disease with severe disease activity and rapid progression, which can lead to detrimental life-long consequences. The pathogenesis of pediatric UC remains unclear, although dysbiosis of the gut microbiota has been considered an important factor. In this study, we collected intestinal mucosal-luminal interface microbiota samples from a cohort of treatment-naïve pediatric UC or control patients and used two different mass spectrometry-based glycomic approaches to examine the N-glycans that were associated with the microbiota. We observed abundant small N-glycans that were associated with the microbiota and found that the pediatric UC microbiota samples contained significantly higher levels of these atypical N-glycans compared to those of controls. Four paucimannosidic or other truncated N-glycans were identified to successfully segregate UC from control patients with an area under the ROC curve of ≥0.9. This study indicates that the aberrant metabolism of glycans in the intestinal by gut microbiota may be involved in the pathogenesis of UC and intestinal N-glycans, including small glycans, can act as novel biomarker candidates for pediatric UC. SIGNIFICANCE: There is no cure for pediatric ulcerative colitis (UC) due to its unclear pathogenesis and the diagnosis of UC in children still largely depends on invasive colonoscopic examination. Recent evidence suggests that the dysbiosis of intestinal microbiota is associated with the onset and development of UC, however how the microbiota interact with the host remains unclear. This study used two different mass spectrometry-based glycomic approaches to quantitatively examine N-glycans that are associated with colonic mucosal-luminal interface microbiota of pediatric UC or control patients. To the best of our knowledge, this is the first comprehensive glycomic study of intestinal microbiota samples in UC, which demonstrated that intestinal microbiota was associated with abundant atypical small N-glycans with elevated levels in UC than controls. This study also identified four intestinal paucimannosidic or other truncated N-glycans as promising biomarker candidates for pediatric UC. These findings shed light on the mechanism study of host-microbiome interactions in UC and indicate that atypical glycans present in the gut can be a source for UC biomarker discovery.

Epidemiologic trend of pediatric inflammatory bowel disease in Latin America: The Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) Working Group

INTRODUCTION AND AIMS

The primary aim was to explore the epidemiologic trend of pediatric inflammatory bowel disease in Latin America, and the secondary aims were to obtain an overview of the diagnostic/therapeutic focus of the members of the LASPGHAN and examine the relation of case frequency to year, during the study period.

MATERIALS AND METHODS

Latin American pediatric gastroenterologists participated in an online survey, conducted through the SurveyMonkey platform, that investigated the yearly frequency of new inflammatory bowel disease patients within the time frame of 2005-2016, their disease variety, the gastrointestinal segments affected, and the diagnostic and treatment methods utilized. The correlation of new case frequency with each study year was evaluated.

RESULTS

A total of 607 patients were studied. The diagnoses were ulcerative colitis in 475 (78.3%) cases, Crohn's disease in 104 (17.1%), and inflammatory bowel disease D unclassified in 28 (4.6%). The trend in ulcerative colitis was a lineal increase in the frequency of new cases related to each study year, with a significant correlation coefficient. Pancolitis was found in 67.6% of the patients. The diagnostic methods included clinical data, endoscopy, and biopsies in more than 99% of the cases, and imaging studies were indicated selectively. Drug regimens were limited to 5-aminosalicylic acid derivatives, azathioprine, 6-mercaptopurine, infliximab, and adalimumab.

CONCLUSIONS

Pediatric inflammatory bowel disease in Latin America appears to have increased during the years included in the study period, with a predominance of moderate or severe ulcerative colitis. That lineal trend suggests the predictive likelihood of a gradual increase in the coming years, with possible epidemiologic and clinical implications.

Associations between Cellular Energy and Pediatric Inflammatory Bowel Disease Patient Response to Treatment

Inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis, are chronic diseases of the gastrointestinal tract, with an unknown etiology, that affect over 6.8 million people worldwide. To characterize disease pathogenesis, proteomic and bioinformatic analyses were performed on colon biopsies collected during diagnostic endoscopy from 119 treatment-naïve pediatric patients, including from 78 IBD patients and 41 non-IBD patients who served as controls. Due to the presence of noninflamed and/or inflamed regions in IBD patients, up to two biopsies were obtained from IBD patients as compared to a single noninflamed biopsy from non-IBD pediatric control patients. Additional biopsies were obtained and analyzed from 33 of the IBD patients after IBD-directed therapeutic intervention for comparison of pre- and post-treatment proteomes. SuperSILAC was utilized to perform quantitative analysis of homogenized tissues, which were processed by filter-aided sample preparation. Hierarchical clustering and principal component analyses revealed proteomic patterns that distinguished inflamed from noninflamed tissues independent of therapy. Gene ontology revealed that proteins downregulated in inflammation are associated with metabolism, whereas upregulated proteins contribute to protein processing. A comparison of pre- and post-treatment proteomes from CD patients identified over 100 proteins that are significantly different between patients who responded and those who did not respond to therapy, including creatine kinase B and basigin.

MR enterography grading of pediatric ileocolonic Crohn disease activity based on a single bowel segment

BACKGROUND

Ileocolonoscopy with histology has been considered the gold standard for Crohn disease (CD) diagnosis and monitoring. Over the last years, magnetic resonance enterography (MRE) has become more and more popular, representing a valid non-invasive technique.

OBJECTIVE

To propose a simplified MRE score, the pediatric CD magnetic resonance index (PCDMRI), based only on the most affected bowel segment, to grade active inflammation in children with CD.

MATERIALS AND METHODS

Two radiologists retrospectively evaluated MRE images of children with histopathology-proven CD. The PCDMRI was based on six mural and perimural variables assessed for the most affected bowel segment (chosen by visual inspection of the key bowel wall imaging findings associated with active inflammation), and five extramural per-examination features. Correlation analysis was performed between both the PCDMRI and the MRE global score (based on all the affected segments) and the pediatric clinical disease activity index (PCDAI), the simple endoscopic score for CD (SES-CD), serum C-reactive protein (CRP) and fecal calprotectin (fC). Inter-reader reproducibility of the scoring system was estimated. Agreement on disease location between MRE and ileocolonoscopy was evaluated.

RESULTS

The study involved 42 children for a total of 80 MRE. PCDMRI and global score positively correlated with PCDAI, SES-CD, CRP and fC. Inter-reader reproducibility was 91%. Agreement on disease location was substantial.

CONCLUSION

The PCDMRI and the global score resulted equally correlated with the PCDAI, suggesting a high impact of the most affected segment on symptoms. The PDCMRI may be a useful non-invasive tool for a rapid and reproducible grading of the disease activity in children with ileocolonic CD.

Emerging Role of Extracellular Vesicles in Biomarking the Gastrointestinal Diseases

INTRODUCTION

Extracellular vesicles (EVs) play an important role in cell-cell communication and regulation of various cellular functions under physiological and pathophysiological conditions through transferring their cargo to recipient cells. Molecular constituents of EVs are a fingerprinting profile of secreting cells which can be used as promising prognostic, diagnostic, and drug-response biomarkers in clinical settings.

AREAS COVERED

The present study provides a brief introduction about the biology of EVs and reviews methodologies used for EV isolation and characterization as well as high-throughput strategies to analyze EV contents. Furthermore, this review highlights the importance and unique role of EVs in the development and progression of gastrointestinal (GI) diseases, especially GI cancers, and then discusses their potential use, particularly those isolated from body fluids, in diagnosis and prognosis of GI diseases.

EXPERT OPINION

In-depth analysis of EV content can lead to the identification of new potential biomarkers for early diagnosis and prognosis prediction of GI diseases. The use of a more targeted approach by establishing more reproducible and standardized methods to decrease variations and obtain desired EV population as well as revisiting large pools of identified biomarkers and their evaluation in larger patient cohorts can result in the introduction of more reliable biomarkers in clinic.

[Position paper on endoscopic reporting in IBD]

The complete and reliable documentation of endoscopic findings make up the crucial foundation for the treatment of patients with inflammatory bowel diseases such as Crohn´s disease and ulcerative colitis. These findings are, on the one hand, a prerequisite for therapeutic decisions and, on the other hand, important as a tool for assessing the response to ongoing treatments. Endoscopic reports should, therefore, be recorded according to standardized criteria to ensure that the findings of different endoscopists can be adequately compared and that changes in the course of the disease can be traced back. In consideration of these necessities, fifteen members of the Imaging Working Group of the German Kompetenznetz Darmerkrankungen have created a position paper proposing a structure and specifications for the documentation of endoscopic exams. In addition to the formal report structure, the recommendations address a large number of attributes of acute and chronic inflammatory alterations as well as endoscopically detectable complications, which are explained in detail and illustrated using exemplary images. In addition, more frequently used endoscopic activity indices are presented and their use in everyday clinical practice is discussed.

Innate Lymphoid Cells in Intestinal Homeostasis and Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a heterogeneous state of chronic intestinal inflammation of unknown cause encompassing Crohn’s disease (CD) and ulcerative colitis (UC). IBD has been linked to genetic and environmental factors, microbiota dysbiosis, exacerbated innate and adaptive immunity and epithelial intestinal barrier dysfunction. IBD is classically associated with gut accumulation of proinflammatory Th1 and Th17 cells accompanied by insufficient Treg numbers and Tr1 immune suppression. Inflammatory T cells guide innate cells to perpetuate a constant hypersensitivity to microbial antigens, tissue injury and chronic intestinal inflammation. Recent studies of intestinal mucosal homeostasis and IBD suggest involvement of innate lymphoid cells (ILCs). These lymphoid-origin cells are innate counterparts of T cells but lack the antigen receptors expressed on B and T cells. ILCs play important roles in the first line of antimicrobial defense and contribute to organ development, tissue protection and regeneration, and mucosal homeostasis by maintaining the balance between antipathogen immunity and commensal tolerance. Intestinal homeostasis requires strict regulation of the quantity and activity of local ILC subpopulations. Recent studies demonstrated that changes to ILCs during IBD contribute to disease development. A better understanding of ILC behavior in gastrointestinal homeostasis and inflammation will provide valuable insights into new approaches to IBD treatment. This review summarizes recent research into ILCs in intestinal homeostasis and the latest advances in the understanding of the role of ILCs in IBD, with particular emphasis on the interaction between microbiota and ILC populations and functions.

Vedolizumab Experience in Children and Adolescents With Inflammatory Bowel Disease: A Multicenter Observational Study

Background

Vedolizumab is increasingly used off-label to treat children and adolescents with inflammatory bowel disease (IBD). In the absence of rigorous clinical trial experience, multicenter observational data are important to establish expectations for efficacy and safety. We examined 1-year outcomes following vedolizumab therapy in a large multicenter pediatric IBD cohort.

Methods

We performed a retrospective study of 159 pediatric patients (4-17 years old) with IBD [78, Crohn disease (CD); 81, ulcerative colitis/IBD-unspecified (UC/IBD-U)] treated with vedolizumab for 1 year at 8 pediatric medical centers in the United States. Demographics, clinical outcomes, laboratory data, and vedolizumab dosing were recorded. The primary outcome was corticosteroid (CS)-free clinical remission at 1 year. Other measured outcomes were clinical remission at 12 and/or 24 weeks, laboratory outcomes at 1 year, and endoscopy/histology results at 1 year.

Results

Among the 159 patients (mean age, 14.5 ± 2.4 years; 86% anti-TNF experienced), 68/159 (43%) achieved CS-free clinical remission at 1 year (CD, 35/78, 45%; UC/IBD-U, 33/81, 40%). Vedolizumab therapy failed and was discontinued in 33/159 (21%) patients prior to 1 year (CD, 18/78, 23%; UC/IBD-U, 15/81, 19%). While week 12 clinical remission was not predictive of 1-year clinical remission in either CD or UC/IBD-U, week 24 clinical remission was predictive of 1-year clinical remission only in CD patients. No infusion reactions or serious side effects were noted.

Conclusions

Vedolizumab was safe and effective in this pediatric population with approximately 43% achieving CS-free clinical remission at 1 year. Similar efficacy was noted in both CD and UC.

Intestinal Microbiota in Common Chronic Inflammatory Disorders Affecting Children

The incidence and prevalence rate of chronic inflammatory disorders is on the rise in the pediatric population. Recent research indicates the crucial role of interactions between the altered intestinal microbiome and the immune system in the pathogenesis of several chronic inflammatory disorders in children, such as inflammatory bowel disease (IBD) and autoimmune diseases, such as type 1 diabetes mellitus (T1DM) and celiac disease (CeD). Here, we review recent knowledge concerning the pathogenic mechanisms underlying these disorders, and summarize the facts suggesting that the initiation and progression of IBD, T1DM, and CeD can be partially attributed to disturbances in the patterns of composition and abundance of the gut microbiota. The standard available therapies for chronic inflammatory disorders in children largely aim to treat symptoms. Although constant efforts are being made to maximize the quality of life for children in the long-term, sustained improvements are still difficult to achieve. Additional challenges are the changing physiology associated with growth and development of children, a population that is particularly susceptible to medication-related adverse effects. In this review, we explore new promising therapeutic approaches aimed at modulation of either gut microbiota or the activity of the immune system to induce a long-lasting remission of chronic inflammatory disorders. Recent preclinical studies and clinical trials have evaluated new approaches, for instance the adoptive transfer of immune cells, with genetically engineered regulatory T cells expressing antigen-specific chimeric antigen receptors. These approaches have revolutionized cancer treatments and have the potential for the protection of high-risk children from developing autoimmune diseases and effective management of inflammatory disorders. The review also focuses on the findings of studies that indicate that the responses to a variety of immunotherapies can be enhanced by strategic manipulation of gut microbiota, thus emphasizing on the importance of proper interaction between the gut microbiota and immune system for sustained health benefits and improvement of the quality of life of pediatric patients.

Incidence of pediatric inflammatory bowel disease within the Vaccine Safety Datalink network and evaluation of association with rotavirus vaccination

BACKGROUND

Recent studies have reported an increase in Inflammatory bowel disease (IBD) incidence in young children, highlighting the need to better understand risk factors for the development of IBD. Licensed for use in infants in 2006, the oral, live-attenuated rotavirus vaccine has biologic plausibility for instigating inflammation of the gut mucosa as a pathway to immune dysregulation.

METHODS

Over a ten-year period, we evaluated incidence of IBD within a cohort of children under the age of ten, enrolled in seven integrated healthcare delivery systems. We conducted a nested case-control study to evaluate the association between rotavirus vaccination and IBD using conditional logistic regression. Cases were confirmed via medical record review and matched to non-IBD controls on date of birth, sex, and study site.

RESULTS

Among 2.4 million children under the age of 10 years, 333 cases of IBD were identified with onset between 2007 and 2016. The crude incidence of IBD increased slightly over the study period (p-value for trend = 0.046). Of the 333 cases, 227 (68%) were born prior to 2007. Forty-two cases born in 2007 or later, with continuous enrollment since birth were included in the case-control study and matched to 210 controls. The adjusted odds ratio for any rotavirus vaccination in IBD cases, compared to matched controls, was 0.72 (95% confidence interval 0.19-2.65).

CONCLUSIONS

Data from this large pediatric cohort demonstrate a small overall increase in IBD incidence in young children over a ten-year period. The data suggest that rotavirus vaccination is not associated with development of IBD.

The Value of Obtaining Colonic Mucosal Biopsies of Grossly Normal Tissue in Pediatric Patients

OBJECTIVES

Current practice during pediatric colonoscopy is to obtain random colonic biopsies, even from normal appearing tissue. The majority of literature published on colonic biopsy practice analyzes adults; however, limited data examines the pediatric population. The lack of standardization regarding tissue sampling during pediatric colonoscopy reinforces the necessity to study this question objectively. The aim of the present study was to assess the value of obtaining mucosal biopsies from grossly normal colonic tissue.

METHODS

A retrospective study was performed to examine the utility of obtaining colonic biopsies from normal appearing tissue. Subjects included patients who underwent colonoscopy during a 2-year period. Descriptive analyses and logistic regression models were used to determine endoscopic and histologic agreement and to characterize predictors of agreement.

RESULTS

The predictive value of agreement between normal appearing colonoscopies (n = 237) and histopathology was 81%. Excluding patients with inflammatory bowel disease (IBD) increased the predictive value to 85%. Two and a half percent of grossly normal colonoscopies had histological findings consistent with newly diagnosed IBD. Predictors of normal histology included abdominal pain (odds ratio [OR] 3.68, 95% CI 1.84-7.37), whereas a known diagnosis of IBD was predictive of abnormal histology (OR 0.22, 95% CI 0.08-0.67). Among the full sample, elevated inflammatory markers (OR 2.02, 95% CI 1.06-3.86) or fatigue (OR 2.60, 95% CI 1.13-5.94) were predictive of abnormal histology.

CONCLUSIONS

Results suggest that colonic biopsies may not need to be routinely obtained from all pediatric colonoscopies, particularly in those patients with complaints of abdominal pain. Biopsies should continue to be obtained from patients with a known diagnosis of IBD, elevated inflammatory markers, or fatigue. Further studies are needed to standardize protocols for biopsy practice in pediatric colonoscopy.

Clinical and Host Biological Factors Predict Colectomy Risk in Children Newly Diagnosed With Ulcerative Colitis

BACKGROUND

Develop a clinical and biological predictive model for colectomy risk in children newly diagnosed with ulcerative colitis (UC).

METHODS

This was a multicenter inception cohort study of children (ages 4-17 years) newly diagnosed with UC treated with standardized initial regimens of mesalamine or corticosteroids (CS) depending upon initial disease severity. Therapy escalation to immunomodulators or infliximab was based on predetermined criteria. Patients were phenotyped by clinical activity per the Pediatric Ulcerative Colitis Activity Index (PUCAI), disease extent, endoscopic/histologic severity, and laboratory markers. In addition, RNA sequencing defined pretreatment rectal gene expression and high density DNA genotyping by the Affymetrix UK Biobank Axiom Array. Coprimary outcomes were colectomy over 3 years and time to colectomy. Generalized linear models, Cox proportional hazards multivariate regression modeling, and Kaplan-Meier plots were used.

RESULTS

Four hundred twenty-eight patients (mean age 13 years) started initial theapy with mesalamine (n = 136), oral CS (n = 144), or intravenous CS (n = 148). Twenty-five (6%) underwent colectomy at ≤1 year, 33 (9%) at ≤2 years, and 35 (13%) at ≤3 years. Further, 32/35 patients who had colectomy failed infliximab. An initial PUCAI ≥ 65 was highly associated with colectomy (P = 0.0001). A logistic regression model predicting colectomy using the PUCAI, hemoglobin, and erythrocyte sedimentation rate had a receiver operating characteristic area under the curve of 0.78 (95% confidence interval [0.73, 0.84]). Addition of a pretreatment rectal gene expression panel reflecting activation of the innate immune system and response to external stimuli and bacteria to the clinical model improved the receiver operating characteristic area under the curve to 0.87 (95% confidence interval [0.82, 0.91]).

CONCLUSIONS

A small group of children newly diagnosed with severe UC still require colectomy despite current therapies. Our gene signature observations suggest additional targets for management of those patients not responding to current medical therapies.

Urinary Metabolites Enable Differential Diagnosis and Therapeutic Monitoring of Pediatric Inflammatory Bowel Disease

Rates of pediatric Crohn's disease (CD) and ulcerative colitis (UC) are increasing globally. Differentiation of these inflammatory bowel disease (IBD) subtypes however can be challenging when relying on invasive endoscopic approaches. We sought to identify urinary metabolic signatures of pediatric IBD at diagnosis, and during induction treatment. Nontargeted metabolite profiling of urine samples from CD (n = 18) and UC (n = 8) in a pediatric retrospective cohort study was performed using multisegment injection-capillary electrophoresis-mass spectrometry. Over 122 urinary metabolites were reliably measured from pediatric IBD patients, and unknown metabolites were identified by tandem mass spectrometry. Dynamic changes in sum-normalized urinary metabolites were also monitored following exclusive enteral nutrition (EEN) or corticosteroid therapy (CS) in repeat urine samples collected over 8 weeks. Higher urinary excretion of indoxyl sulfate, hydroxyindoxyl sulfate, phenylacetylglutamine, and sialic acid were measured in CD as compared to UC patients, but lower threonine, serine, kynurenine, and hypoxanthine (p < 0.05). Excellent discrimination of CD from UC was achieved based on the urinary serine:indoxylsulfate ratio (AUC = 0.972; p = 3.21 × 10^-5). Urinary octanoyl glucuronide, pantothenic acid, and pyridoxic acid were also identified as specific dietary biomarkers of EEN in pediatric IBD patients who achieved clinical remission. This work may complement or replace existing strategies in the diagnosis and early management of children with IBD.

Are biopsies always necessary in upper and lower gastrointestinal endoscopy in children? A retrospective 10-year analysis

Little attention has been given to the efficiency and validity of performing routine endoscopic biopsies in normal areas in children. This study aimed to investigate the need to perform routine biopsies in upper gastrointestinal endoscopy (UDE) and colonoscopy in normal areas by comparing macroscopy and histology. It was a 10-year retrospective analysis with the inclusion of 761 UDEs and 177 colonoscopies. Considering all segments, UDEs showed false-positive result rates of 73.11% and false-negative result rates of 14.34%. The histological results modified the initial management in 53.95% of patients. Considering all segments, colonoscopies showed false-positive result rates of 63.64% and false-negative result rates of 30.97%. The histological results modified the initial management in 34.45% of patients.Conclusion: If biopsies were obtained only in abnormal areas, the diagnosis would be lost in 53.95% of the patients in upper endoscopies and 85.7% of the colonoscopies, which justifies routine maintenance of biopsies in macroscopically normal areas in children. What is Known: • Little attention has been given to the efficiency and validity of endoscopic biopsies of normal areas during pediatric exams. • Only a few pediatric studies have correlated macroscopic and histological findings from endoscopic biopsies, and low sensitivity and specificity, as well as poor agreement, were reported. What is New: • Our study confirms the evidence that routine biopsies from macroscopically normal areas during upper and lower digestive endoscopies can lead to histopathological diagnoses and different medical management. • This is the first research on this topic in a Latin population, from a developing country, reassuring the results obtained in previous papers from other countries.

Gut microbiome-based supervised machine learning for clinical diagnosis of inflammatory bowel diseases

Despite the availability of various diagnostic tests for inflammatory bowel diseases (IBD), misdiagnosis of IBD occurs frequently, and thus, there is a clinical need to further improve the diagnosis of IBD. As gut dysbiosis is reported in patients with IBD, we hypothesized that supervised machine learning (ML) could be used to analyze gut microbiome data for predictive diagnostics of IBD. To test our hypothesis, fecal 16S metagenomic data of 729 subjects with IBD and 700 subjects without IBD from the American Gut Project were analyzed using five different ML algorithms. Fifty differential bacterial taxa were identified [linear discriminant analysis effect size (LEfSe): linear discriminant analysis (LDA) score > 3] between the IBD and non-IBD groups, and ML classifications trained with these taxonomic features using random forest (RF) achieved a testing area under the receiver operating characteristic curves (AUC) of ∼0.80. Next, we tested if operational taxonomic units (OTUs), instead of bacterial taxa, could be used as ML features for diagnostic classification of IBD. Top 500 high-variance OTUs were used for ML training, and an improved testing AUC of ∼0.82 (RF) was achieved. Lastly, we tested if supervised ML could be used for differentiating Crohn's disease (CD) and ulcerative colitis (UC). Using 331 CD and 141 UC samples, 117 differential bacterial taxa (LEfSe: LDA score > 3) were identified, and the RF model trained with differential taxonomic features or high-variance OTU features achieved a testing AUC > 0.90. In summary, our study demonstrates the promising potential of artificial intelligence via supervised ML modeling for predictive diagnostics of IBD using gut microbiome data.NEW & NOTEWORTHY Our study demonstrates the promising potential of artificial intelligence via supervised machine learning modeling for predictive diagnostics of different types of inflammatory bowel diseases using fecal gut microbiome data.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Early Serum Infliximab Levels in Pediatric Ulcerative Colitis

Background: Data on serum infliximab concentrations during induction in pediatric ulcerative colitis are limited. The study aim is to evaluate the relationship between serum infliximab concentrations during induction and short-term clinical remission in children with ulcerative colitis. Methods: We carried out a prospective, multi-center cohort study in pediatric patients with ulcerative colitis. Serum infliximab concentrations were collected at peak dose #1, week 1, trough pre-dose #2, and trough pre-dose #3. Infliximab dosing was left to investigator discretion. Clinical remission was defined by pediatric ulcerative colitis activity index <10 at week 8. Results: Twenty-four of thirty-four subjects (71%) achieved clinical remission at week 8. The median infliximab concentrations were 33.0 μg/mL (interquartile range: 26.5-52.1 μg/mL) pre-dose #2 and 22.5 μg/mL (interquartile range:15.9-32.3 μg/mL) pre-dose #3. Trough pre-dose #2 infliximab concentration yielded area under receiver operator characteristic curve 0.7, 95% CI: 0.5-0.9 in predicting week 8 clinical remission; a cut-off of 33.0 μg/mL yielded 62.5% sensitivity, 66.7% specificity. Trough pre-dose #3 infliximab concentrations were lower for subjects <10 years compared to ≥ 10 years [median 15.9 μg/mL, interquartile range (IQR) 8.5-21.8 μg/mL vs. 27.7 μg/mL, IQR 17.2-46.7 μg/mL, p = 0.01] and correlated with baseline weight (Spearman's rank correlation coefficient 0.45, p = 0.01). The median half-life following first IFX dose was 6.04 days (IQR 5.3-7.9 days). Conclusions: Infliximab concentrations ≥33 μg/mL prior to the second dose were associated with week 8 clinical remission. As young age and low body weight impact infliximab concentration, prospective studies with proactive adjustment in pediatric patients with ulcerative colitis should be carried out. Clinicians caring for children with UC should diligently adjust and monitor infliximab to optimize response.

Perianal lesions as an unusual first manifestation of Crohn's disease in pediatric patients - case series

Primary symptoms of Crohn's disease usually include, among others, abdominal pain and cramping, recurrent diarrhea, fever and weight loss. The aim of this study was to show the effectiveness of ultrasound in the diagnosis and assessment of the extent of perianal complications in Crohn's disease. Five patients (four boys and one girl) aged from 13 to 16 years, with prolonged pain in the perianal area, which worsened when sitting, were admitted to the Department of Pediatric Gastroenterology between 2017 and 2019. Each patient underwent intestinal ultrasound with a high frequency 7-12 MHz linear probe and transperineal ultrasound to assess the anal canal and the surrounding soft tissues. In each case, the echogenicity of the bowel wall was assessed for mural stratification and possible thickening. Anorectal fistulas were detected in all the five patients. Three patients (12 y.o. male, 12 y.o. female and 16 y.o. male) presented with perianal abscesses drained by fistulas. In the first patient the fistula was limited to the perianal soft tissue (22 × 23 mm); in the second patient it was localized within the ischioanal region (40 × 50 mm); and in the third patient (5-6 mm abscess) the fistula was with a hypoechoic fistulous tract reaching the sphincter. All of the patients were eventually diagnosed with Crohn's disease as a result of further clinical workup. Ultrasound examination is a non-invasive, well-tolerated modality for the evaluation of Crohn's disease activity and its possible complications, e.g. fistulas and abscesses. Ultrasound is especially useful in patients who require repeated follow-up investigations.

Ulcerative Colitis: Making the Diagnosis

Ulcerative colitis is an inflammatory condition of the colon. The diagnosis of ulcerative colitis is based on clinical presentation, endoscopic evaluation, and histologic parameters in the absence of demonstrable alternate etiology. The differential diagnosis remains broad, and infection in particular must be considered and excluded. Although laboratory and radiographic findings can aid in the diagnosis of ulcerative colitis, endoscopy remains the gold standard for diagnosis. A correct diagnosis and disease staging are imperative because these factors affect treatment options and prognosis.

Epidemiologic trend of pediatric inflammatory bowel disease in Latin America: The Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) Working Group

INTRODUCTION AND OBJECTIVES

The primary aim was to explore the epidemiologic trend of pediatric inflammatory bowel disease in Latin America, and the secondary aims were to obtain an overview of the diagnostic/therapeutic focus of the members of the LASPGHAN and examine the relation of case frequency to year, during the study period.

MATERIALS AND METHODS

Latin American pediatric gastroenterologists participated in an online survey, conducted through the SurveyMonkey platform, that investigated the yearly frequency of new inflammatory bowel disease patients within the time frame of 2005 to 2016, their disease variety, the gastrointestinal segments affected, and the diagnostic and treatment methods utilized. The correlation of new case frequency with each study year was evaluated.

RESULTS

A total of 607 patients were studied. The diagnoses were ulcerative colitis in 475 (78.3%) cases, Crohn's disease in 104 (17.1%), and inflammatory bowel disease D unclassified in 28 (4.6%). The trend in ulcerative colitis was a lineal increase in the frequency of new cases related to each study year, with a significant correlation coefficient. Pancolitis was found in 67.6% of the patients. The diagnostic methods included clinical data, endoscopy, and biopsies in more than 99% of the cases, and imaging studies were indicated selectively. Drug regimens were limited to 5-aminosalicylic acid derivatives, azathioprine, 6-mercaptopurine, infliximab, and adalimumab.

CONCLUSIONS

Pediatric inflammatory bowel disease in Latin America appears to have increased during the years included in the study period, with a predominance of moderate or severe ulcerative colitis. That lineal trend suggests the predictive likelihood of a gradual increase in the coming years, with possible epidemiologic and clinical implications.

Identification and diagnosis of Crohn disease and ulcerative colitis in children

Crohn disease and ulcerative colitis are the two main types of inflammatory bowel disease. High rates of these conditions are seen in Australasian children - furthermore, increasing rates have been evident in recent years. Children can present with typical symptoms of abdominal pain, diarrhoea, haematochezia and/or weight loss. Atypical presentations (such as skin lesions or isolated short stature) can also occur: these may be associated with delays in the consideration and diagnosis of IBD. Initial steps in establishing a diagnosis of IBD include delineation of inflammatory markers exclusion of any other likely aetiology. Definitive diagnosis relies upon key endoscopic, histologic and radiological findings. Overall management of IBD encompasses care within a team-based, child and family-focused, multi-disciplinary setting.

Growth and Puberty in Children with Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are gastrointestinal tract pathologies of unknown etiology; they have an alternating trend, with active and silent phases. IBD are classified in two main forms: ulcerative colitis (UC) and Crohn’s disease (CD). Both have chronic and recurrent course, gastrointestinal symptoms, and extraintestinal manifestations. The altered immune response role seems to be important both in UC and CD. In the majority of cases, CD begins with abdominal pain, diarrhea, decrease in appetite, and weight loss; there can be also perianal fistulas, rhagades, and perianal recurrent abscesses. In addition, retarded growth and delayed puberty can precede the development of the disease or can even be predominant at onset. Growth retardation is found in 40% of IBD patients, but the underlying mechanism of this and other extra-intestinal manifestations are partially known: the main hypotheses are represented by malnutrition and inflammatory response during the active phase of the disease. The increased level of pro-inflammatory cytokines can influence growth, but also the onset of puberty and its progression. In addition, it could be essential to clarify the role and the possible effects of all the currently used treatments concerning growth failure and delayed puberty.

Development and evaluation of an EHR-based computable phenotype for identification of pediatric Crohn's disease patients in a National Pediatric Learning Health System

Objectives

To develop and evaluate the classification accuracy of a computable phenotype for pediatric Crohn's disease using electronic health record data from PEDSnet, a large, multi‐institutional research network and Learning Health System.

Study Design

Using clinician and informatician input, algorithms were developed using combinations of diagnostic and medication data drawn from the PEDSnet clinical dataset which is comprised of 5.6 million children from eight U.S. academic children's health systems. Six test algorithms (four cases, two non‐cases) that combined use of specific medications for Crohn's disease plus the presence of Crohn's diagnosis were initially tested against the entire PEDSnet dataset. From these, three were selected for performance assessment using manual chart review (primary case algorithm, n = 360, primary non‐case algorithm, n = 360, and alternative case algorithm, n = 80). Non‐cases were patients having gastrointestinal diagnoses other than inflammatory bowel disease. Sensitivity, specificity, and positive predictive value (PPV) were assessed for the primary case and primary non‐case algorithms.

Results

Of the six algorithms tested, the least restrictive algorithm requiring just ≥1 Crohn's diagnosis code yielded 11 950 cases across PEDSnet (prevalence 21/10 000). The most restrictive algorithm requiring ≥3 Crohn's disease diagnoses plus at least one medication yielded 7868 patients (prevalence 14/10 000). The most restrictive algorithm had the highest PPV (95%) and high sensitivity (91%) and specificity (94%). False positives were due primarily to a diagnosis reversal (from Crohn's disease to ulcerative colitis) or having a diagnosis of “indeterminate colitis.” False negatives were rare.

Conclusions

Using diagnosis codes and medications available from PEDSnet, we developed a computable phenotype for pediatric Crohn's disease that had high specificity, sensitivity and predictive value. This process will be of use for developing computable phenotypes for other pediatric diseases, to facilitate cohort identification for retrospective and prospective studies, and to optimize clinical care through the PEDSnet Learning Health System.

Ovarian Crohn's Disease: A Case Report and Review of the Literature

We present to you a rare case of Crohn's disease involving the ovary in a 28-year-old nulligravida Eritrean patient. This is considered a rare manifestation of Crohn's disease that is believed to be due to fistulization between the ovary and intestines.

Adipokine Resistin Levels at Time of Pediatric Crohn Disease Diagnosis Predict Escalation to Biologic Therapy

BACKGROUND

Hypertrophy of visceral adipose tissue (VAT) is a hallmark of Crohn disease (CD). The VAT produces a wide range of adipokines, biologically active factors that contribute to metabolic disorders in addition to CD pathogenesis. The study aim was to concomitantly evaluate serum adipokine profiles and VAT volumes as predictors of disease outcomes and treatment course in newly diagnosed pediatric patients with CD.

METHODS

Pediatric patients ages 6 to 20 years were enrolled, and their clinical data and anthropometric measurements were obtained. Adipokine levels were measured at 0, 6, and 12 months after CD diagnosis and baseline in control patients (CP). The VAT volumes were measured by magnetic resonance imaging or computed tomography imaging within 3 months of diagnosis.

RESULTS

One hundred four patients undergoing colonoscopy were prospectively enrolled: 36 diagnosed with CD and 68 CP. The serum adipokine resistin and plasminogen activator inhibitor (PAI)-1 levels were significantly higher in patients with CD at diagnosis than in CP. The VAT volume was similar between CD and CP. Baseline resistin levels at the time of diagnosis in patients with CD who were escalated to biologics was significantly higher than in those not treated using biologic therapy by 12 months (29.8 ng/mL vs 13.8 ng/mL; P = 0.004). A resistin level of ≥29.8 ng/mL at the time of diagnosis predicted escalation to biologic therapy in the first year after diagnosis with a specificity of 95% (sensitivity = 53%; area under the curve = 0.82; P = 0.015 for model with log-scale). There was a significantly greater reduction in resistin (P = 0.002) and PAI-1 (P = 0.010) at the 12-month follow-up in patients on biologics compared with patients who were not treated using biologics.

CONCLUSIONS

Serum resistin levels at diagnosis of pediatric CD predict the escalation to biologic therapy at 12 months, independent of VAT volumes. Resistin and PAI-1 levels significantly improved in patients with CD after treatment using biologics compared with those not on biologics. These results suggest the utility of resistin as a predictive biomarker in pediatric CD.

Upper Gastrointestinal Manifestations of Inflammatory Bowel Disease

Although the features of lower gastrointestinal tract inflammation associated with ulcerative colitis and Crohn disease are generally familiar to pathologists, there is less awareness of and familiarity with the manifestations of inflammatory bowel disease in the esophagus, stomach, and duodenum. Nonetheless, their diagnosis has therapeutic and possibly prognostic implications, potentially foretelling severe complications. The recognition that ulcerative colitis can affect gastrointestinal organs proximal to the large intestine and terminal ileum represents a revision of concepts ingrained among generations of physicians. This article reviews the pathologic features and clinical significance of esophagitis, gastritis, and duodenitis associated with inflammatory bowel disease.

Site-specific targeted drug delivery systems for the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) includes Crohn's disease and ulcerative colitis and manifests as a complex and dysregulated immune response. To date, there is no cure for IBD; thus, lifelong administration of maintenance drugs is often necessary. Since conventional IBD treatment strategies do not target the sites of inflammation, only limited efficacy is observed with their use. Moreover, the possibility of severe side effects resulting from systemic drug redistribution is high when conventional drug treatments are used. Therefore, a straightforward disease-targeted drug delivery system is desirable. Based on the pathophysiological changes associated with IBD, novel site-specific targeted drug delivery strategies that deliver drugs directly to the inflammation sites can enhance drug accumulation and decrease side effects. This review summarizes novel inflammation targeted delivery systems in the management of IBD. It also discusses the challenges and new perspectives in this field.

Upper Gastrointestinal Disease Influences the Occurrence of Inflammatory Bowel Disease

BACKGROUND AND AIMS

Compromise of the gastric acid barrier may facilitate bacterial invasion of the lower intestinal tract and influence the occurrence of inflammatory bowel disease (IBD). Our study tested the associations between histopathologic changes in the upper and lower gastrointestinal tract in patients undergoing bidirectional endoscopy.

METHODS

The Inform Diagnostics database is a national electronic repository of histopathologic records of patients distributed throughout the entire USA. A case-control study among 302,061 patients, of whom 13,943 harbored IBD, evaluated whether the occurrence of Crohn's disease or ulcerative colitis was influenced by the presence of various upper gastrointestinal diagnoses associated with lowered gastric acid output. The influence of individual risk factors on the occurrence of colonic disease was expressed as odds ratios with their 95% confidence intervals.

RESULTS

The odds ratio for Crohn's disease being associated with gastric H. pylori was 0.30 (0.24-0.37), with intestinal metaplasia 0.30 (0.24-0.39), with fundic gland polyps 0.42 (0.35-0.50), with gastric hyperplastic polyps 0.35 (0.23-0.51), with Barrett's metaplasia 0.19 (0.14-0.24), and with reflux esophagitis 0.46 (0.42-0.51). The odds ratio for ulcerative colitis being associated with gastric H. pylori was 0.58 (0.50-0.67), with intestinal metaplasia 0.39 (0.32-0.47), with fundic gland polyps 0.61 (0.53-0.71), with gastric hyperplastic polyps 0.64 (0.49-0.84), with Barrett's metaplasia 0.50 (0.43-0.59), and with reflux esophagitis 0.77 (0.71-0.84).

CONCLUSIONS

A diminished gastric acid barrier function, as evidenced by various upper gastrointestinal diseases associated with lowered gastric acid output, may exert a protective influence against the development of inflammatory bowel disease.

Thalidomide for de novo Crohn's disease after ileal pouch anal anastomosis for ulcerative colitis

WHAT IS KNOWN AND THE OBJECTIVE

De novo Crohn's disease (CD) is an increasingly reported diagnosis after ileal pouch anal anastomosis (IPAA). Currently, no consensus exists on the best treatment strategy.

CASE SUMMARY

This report details the case of a 5-year-old child with early-onset ulcerative colitis (UC) who developed findings compatible with CD 12 months after IPAA. Thalidomide therapy led to clinical and endoscopic remission without side effects at 6 months.

WHAT IS NEW AND CONCLUSION

To our knowledge, this is the first report of thalidomide for treatment of de novo CD. Thalidomide therapy could be considered in patients with de novo CD, with similar indications of CD.