Disaccharidase Deficiency in Pediatric Patients with Inflammatory Bowel Disease

Background: Disaccharidase (DS) deficiencies have been reported in pediatric patients with inflammatory bowel disease (IBD), but the relationship between duodenal inflammation and DS deficiency has not been evaluated outside of lactase deficiency. Methods: This study assessed DS levels and DS deficiencies in pediatric IBD patients who underwent endoscopy with assessment of DS activity. Records were reviewed for IBD subtype, pathology findings, and the results of DS analysis. Results: A total of 136 patients were identified. Overall, 89 (65.4%) patients had a diagnosis of Crohn’s disease (CD), 31 (22.8%) patients had a diagnosis of ulcerative colitis (UC), and 16 (11.8%) patients had a diagnosis of indeterminant colitis. Lactase deficiency was identified in 55.9% of patients, followed by maltase deficiency (19.9%), sucrase and palatinase deficiency (14%), and pan-deficiency (12.5%). When analyzing only patients with CD, patients with duodenitis were more likely to exhibit sucrase deficiency, palatinase deficiency, and pan-deficiency with a trend towards maltase deficiency. Conclusions: The most common DS deficiency was lactase deficiency; however, this was not related to duodenal inflammation. Pediatric patients with CD and duodenal inflammation exhibit DS deficiencies, namely, sucrase, palatinase, and pan-deficiency. Dietary adjustments may be warranted temporarily until duodenal inflammation is healed in patients with CD and duodenitis.

Incidence and Prevalence Trends of Pediatric Inflammatory Bowel Disease in the Daegu-Kyungpook Province From 2017 to 2020

Background and Aim: There is paucity of data regarding the epidemiology of pediatric IBD in Asia compared to that of Western countries. We aimed to investigate the incidence and prevalence trends of pediatric inflammatory bowel disease (IBD) in the Daegu-Kyungpook province of South Korea from 2017 to 2020.Methods: This study was a multicenter, retrospective study conducted in eight IBD referral centers located in the Daegu-Kyungpook province. Children and adolescents of ≤18 years who were initially diagnosed with IBD between 2017 and 2020 were included. The annual number of children and adolescents newly diagnosed with IBD and the annual resident population of children and adolescents ≤18 years of age in the Daegu-Kyungpook province were investigated to calculate the annual incidence and prevalence in the region.Results: A total 304 children and adolescents that had been diagnosed with IBD were included in this study. Among these patients, 71.4% had been diagnosed with Crohn's disease (CD), and 28.6% with ulcerative colitis (UC). The population based annual incidences of IBD from 2017 to 2020 were each 7.24, 6.82, 10.27, and 13.33 per 100,000, respectively (P for trend <0.001), 4.48, 5.26, 7.39, and 9.8 per 100,000, respectively, for CD (P for trend <0.001), and 2.76, 1.56, 2.88, and 3.53 per 100,000, respectively, for UC (P for trend = 0.174).Conclusion: Pediatric IBD, especially CD has significantly increased recently in the Daegu-Kyungpook province. Epidemiology studies from other regions of Asia are required to better elucidate this trend of increase in Asia.

Fecal Amino Acid Analysis in Newly Diagnosed Pediatric Inflammatory Bowel Disease: A Multicenter Case-Control Study

Background Fecal metabolomic profiles differ between pediatric inflammatory bowel disease (IBD) patients and controls and may provide new insights in the pathophysiology of IBD. The role of amino acids, however, is not fully elucidated. We aimed to assess fecal amino acid profiles in pediatric IBD. Methods In this case-control study, treatment-naïve, newly diagnosed pediatric IBD patients and a non-IBD control group, matched based on sex and age, were included in 2 tertiary centres. Fecal amino acid profiles were assessed using a targeted high-performance liquid chromatography technique. A random forest classifier method was used to develop a prediction model differentiating IBD from controls and predicting IBD phenotype. The association between IBD localization and amino acid concentrations was tested with ordinal regression models. Results We included 78 newly diagnosed IBD patients (40 Crohn’s disease [CD], 38 ulcerative colitis [UC]) and 105 controls. Patients with IBD could be differentiated from controls with an accuracy of 82% (sensitivity 63%, specificity 97%). Twenty-nine out of the 42 measured unique amino acids were included in the prediction model. Increased levels of tryptophan, taurine, alanine, ornithine, valine, histidine, and leucine were the most differentiating features. Children with CD and UC could be differentiated from the controls with an accuracy of 80% and 90%, respectively. Inflammatory bowel disease phenotype could not be predicted. Tryptophan, valine, and histidine levels were positively associated with more extended disease in UC patients (P < .05). Conclusions Fecal amino acids may enhance understanding of the role of host-microbial interactions in the pathophysiology of IBD and may evolve into biomarkers for pediatric IBD diagnostic and personalized medicine.

Increasing Rate of a Positive Family History of Inflammatory Bowel Disease (IBD) in Pediatric IBD Patients

The role of a positive family history in pediatric inflammatory bowel disease (IBD) in the era of biologic therapy has not been elucidated. We retrospectively reviewed the medical records of children with IBD and retrieved demographic and clinical characteristics, including the presence of a positive family history of IBD, IBD phenotype, disease course, and therapy. Overall, 325 children (age range at diagnosis 11-15 years) were included, of whom 82 (25.2%) had a positive family history. Children diagnosed during 2016-2020 had a higher frequency of positive family history compared to those diagnosed during 2010-2015 (31.8% versus 20.7%, respectively, p = 0.024). Children with a positive family history had a higher risk for a stricturing phenotype than those with a negative family history (11.3% versus 2.8%, respectively, p = 0.052). They more often received nutritional therapy (53.7% versus 36.6%, p = 0.007) and less often received corticosteroids (36.6% versus 52.7%, p = 0.012). More children with a negative family history needed intensification of biologic therapy (p = 0.041). Conclusion: The rate of a positive family history of IBD in the pediatric IBD population is increasing. A positive family history may have some impact upon IBD phenotype but none on IBD outcome.

Seroconversion following SARS-CoV-2 Infection or Vaccination in Pediatric IBD Patients

Objective: Inflammatory bowel disease (IBD) patients are commonly treated with immunomodulatory medications, and the effect of these medications on seroconversion to SARS-CoV-2 infection and vaccination are scant, particularly in pediatrics. We sought to determine serologic responses to SARS-CoV-2 infection and vaccination in pediatric IBD patients. Design: We conducted a single-center, retrospective study of all pediatric (≤21 years old) IBD patients in whom a SARS-CoV-2 IgG Antibody Assay was performed between April 2020 and May 2021 at our tertiary care center. This assay measures IgG antibody to the full-length SARS-CoV-2 spike protein and was routinely collected at infusion and outpatient clinic visits. The primary outcome was SARS-CoV-2 seroconversion, and the secondary outcome was titer level, with high titer defined as ≥960 titer or >40 AU/mL. Clinical characteristics, including demographics, IBD location, behavior, activity, and therapy, SARS-CoV-2 exposures, COVID-19 testing and symptoms, SARS-CoV-2 infection status (WHO COVID-19: Case Definitions, 2020) and COVID-19 vaccination status and type, were gathered, and univariate analyses examined associations between clinical characteristics and outcome measures. Results: There were 340 pediatric patients with SARS-CoV-2 Antibody Testing; 15% for confirmed or probable COVID-19, 2% for suspected COVID-19, 16% for asymptomatic exposure to a close contact with SARS-CoV-2 infection, 61% without any prior symptoms or exposures, and 6% for history of COVID-19 vaccination. Patients with confirmed or probable COVID-19 infection had a 90% rate of seroconversion, with 76% of these patients on biologic therapy. Patients post-infection without seroconversion had a significantly longer interval between infection and antibody assay (P=0.03). Within those with asymptomatic SARS-CoV-2 exposure, 43% had seroconversion, and there were no identified clinical characteristics associated with positive titer. All pediatric patients who received vaccination seroconverted, and all who received mRNA vaccinations, including one after a single dose, achieved high titer levels; 100% of those who received vaccination were on biologic or small molecule therapy, including one on combination therapy with ustekinumab and tofacitinib. Conclusion: Pediatric IBD patients have strong serologic antibody responses to SARS-CoV-2 infection and COVID-19 vaccination despite high rates of immunomodulatory therapy.

Potential Role of Methotrexate Polyglutamates in Therapeutic Drug Monitoring for Pediatric Inflammatory Bowel Disease

Inside cells, the immunomodulator methotrexate (MTX) undergoes the addition of glutamates to form methotrexate polyglutamates (MTX-Glu)—promising biomarkers of systemic exposure and treatment response to MTX in rheumatology. MTX-Glu are underexplored in Inflammatory Bowel Disease (IBD), with no data in pediatrics. In this cross-sectional secondary analysis, we assessed the relationships between MTX-Glu and MTX dose and treatment response in pediatric IBD. Twenty-one children with IBD, receiving maintenance therapy with infliximab (IFX) and MTX, had MTX-Glu1–6 concentrations and IFX troughs/antibodies measured and disease activity assessed for comparison in remission vs. active IBD using non-parametric tests, with associations explored using Spearman’s correlation (ρ) and regression analyses; SASv9.4 (α = 0.05). Total and long-chain MTX-Glu correlated with MTX dose (ρ = 0.51 and 0.56, respectively; p ≤ 0.02). In children with Crohn’s disease (n = 19), short-chain MTX-Glu1–2 were 2.5-fold higher in remission vs. active disease, approaching statistical significance (p = 0.066), with no statistical differences in IFX trough (p = 0.549) between groups. Our study highlights a potential role for long-chain MTX-Glu in the therapeutic drug monitoring of MTX in IBD. It is the first study in pediatric IBD and, although statistical significance was not reached, our findings also suggest that higher short-chain MTX-Glu levels may be associated with IBD treatment response to MTX in children.