Gene signatures of early response to anti-TNF drugs in pediatric inflammatory bowel disease

T. Around a 20–30% of inflammatory bowel disease (IBD) patients are diagnosed before they are 18 years old. Anti-TNF drugs can induce and maintain remission in IBD, however, up to 30% of patients do not respond. The aim of the work was to identify markers that would predict an early response to anti-TNF drugs in pediatric patients with IBD. The study population included 43 patients aged <18 years with IBD who started treatment with infliximab or adalimumab. Patients were classified into primary responders (n = 27) and non-responders to anti-TNF therapy (n = 6). Response to treatment could not be analyzed in 10 patients. Response was defined as a decrease in over 15 points in the disease activity indexes from week 0 to week 10 of infliximab treatment or from week 0 to week 26 of adalimumab treatment. The expression profiles of nine genes in total RNA isolated from the whole-blood of pediatric IBD patients taken before biologic administration and after 2 weeks were analyzed using qPCR and the 2−∆∆Ct method. Before initiation and after 2 weeks of treatment the expression of SMAD7 was decreased in patients who were considered as non-responders (p value < 0.05). Changes in expression were also observed for TLR2 at T0 and T2, although that did not reach the level of statistical significance. In addition, the expression of DEFA5 decreased 1.75-fold during the first 2 weeks of anti-TNF treatment in responders, whereas no changes were observed in non-responders. Expression of the SMAD7 gene is a pharmacogenomic biomarker of early response to anti-TNF agents in pediatric IBD. TLR2 and DEFA5 need to be validated in larger studies.This work was funded by Instituto de Salud Carlos III (grants numbers PI16/00559 and PI19/00792), Consejería de Educación y Deporte de la Comunidad de Madrid (grant number PEJ16/MED/AI-1260), and by the Gregorio Marañón Health Research Institute (grant number PRE-2018-2), The study was cofunded by ERDF Funds (FEDER) from the European Commission, “A way of making Europe

HLA-DQ distribution and risk assessment of celiac disease in a Spanish center

ABSTRACT Aims: celiac disease is a multisystem immune-mediated disease triggered by gluten in genetically susceptible individuals. The HLA-DQ2 and/or HLA-DQ8 heterodimers are encoded by the main genetic predisposing factors and their presence is required for the development of the immunological response that leads to the disease. However, the HLA-conferred risk can differ within different countries. The aim of the study was to analyze the risk of Spanish children to develop celiac disease according to their HLA-DQ genotype. Methods: a retrospective observational case-control study was performed using a sample of 475 celiac patients and 628 controls. Results: children carrying the HLA-DQ2.5 had the highest disease risk, especially those with two HLA-DQB1*02 alleles. A similar high risk was observed in HLA-DQ8 homozygous individuals. A risk conferred by HLA-DQ8 in heterozygosity and HLA-DQ2.2 was also found and two patients with celiac disease carried the HLA-DQ7.5 haplotype as the only HLA risk factor. Conclusions: there are four genetic risk categories according to the HLA-DQ genotype. The HLA-DQ7.5 genotype does not confer risk but should not be used to rule out celiac disease when a high suspicion of the disease exists. These findings could be relevant to determine when to perform serological screening in asymptomatic subjects at risk of celiac disease

Efficacy of a point-of-care test based on deamidated gliadin peptides for the detection of celiac disease in pediatric patients

Objective: The objective of the study was to assess the effectiveness of a point-of-care test (POCT) based on deamidated gliadin peptides (DGP) compared to the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) criteria diagnosis in the early detection of celiac disease (CD) in pediatric patients. Methods: One hundred children (≤ 18 years) with suspected CD were selected, including siblings of celiac children that underwent gastroscopy for other gastrointestinal conditions. Patients with severe disease, following a gluten-free diet (GFD), with gastrointestinal bleeding, coagulopathy and infections in the last month were excluded. All children were evaluated with a POCT that detects immunoglobulin A (IgA) and immunoglobulin G (IgG) antibodies to DGP and total IgA. The POCT results were compared to CD diagnosis according to current ESPGHAN criteria. This involved the detection of IgA tissue transglutaminase (tTG) antibodies, the results of an intestinal biopsy and genetic testing. Results: The prevalence of CD found in the present study was 48% (95% confidence interval in parenthesis 37.9-58.2%). The results of the POCT were concordant with the CD diagnosis made according to ESPGHAN criteria: 95.8% (85.7-99.4%) sensitivity, 98.1% (89.7-99.7%) specificity, 97.9% (88.7-99.6%) positive predictive value and 96.2% (87.0-99.4%) negative predictive value. Positive and negative likelihood ratios were 49.8 (7.2-347.5) and 0.04 (0.01-0.17), respectively. The POCT showed a 100% diagnostic accuracy in children younger than ten years of age. In total, three discordant results were found. Conclusion: Due to the high diagnostic accuracy in the pediatric population, the POCT can be considered as an effective tool for the early diagnosis of CD, especially in patients younger than ten years of age

Trends in Faecal Zonulin Concentrations in Paediatric Patients with Celiac Disease at Baseline and on a Gluten-Free Diet: Exploring Correlations with Other Faecal Biomarkers

Celiac disease (CeD) is an autoimmune condition triggered by gluten in genetically predisposed individuals, affecting all ages. Intestinal permeability (IP) is crucial in the pathogenesis of CeD and it is primarily governed by tight junctions (TJs) that uphold the intestinal barrier’s integrity. The protein zonulin plays a critical role in modulating the permeability of TJs having emerged as a potential non-invasive biomarker to study IP. The importance of this study lies in providing evidence for the usefulness of a non-invasive tool in the study of IP both at baseline and in the follow-up of paediatric patients with CeD. In this single-centre prospective observational study, we explored the correlation between faecal zonulin levels and others faecal and serum biomarkers for monitoring IP in CeD within the paediatric population. We also aimed to establish reference values for faecal zonulin in the paediatric population. We found that faecal zonulin and calprotectin values are higher at the onset of CeD compared with the control population. Specifically, the zonulin levels were 347.5 ng/mL as opposed to 177.7 ng/mL in the control population (p = 0.001), while calprotectin levels were 29.8 μg/g stool compared to 13.9 μg/g stool (p = 0.029). As the duration without gluten consumption increased, a significant reduction in faecal zonulin levels was observed in patients with CeD (348.5 ng/mL vs. 157.1 ng/mL; p = 0.002), along with a decrease in the prevalence of patients with vitamin D insufficiency (88.9% vs. 77.8%). We conclude that faecal zonulin concentrations were higher in the patients with active CeD compared with healthy individuals or those following a gluten-free diet (GFD). The significant decrease in their values over the duration of the GFD suggests the potential use of zonulin as an additional tool in monitoring adherence to a GFD

Coeliac disease case-control study: Has the time come to explore beyond patients at risk?

The worldwide prevalence of asymptomatic coeliac disease (CD) is increasing, which is in part due to the routine screening of children with risk factors. Both symptomatic and asymptomatic patients with CD are at risk of long-term complications. The objective of this study was to compare the clinical characteristics of asymptomatic and symptomatic children at the time of CD diagnosis. A case-control study was conducted using data from a cohort of 4838 CD patients recruited from 73 centers across Spain between 2011 and 2017. A total of 468 asymptomatic patients (cases) were selected and matched by age and sex with 468 symptomatic patients (controls). Clinical data, including any reported symptoms, as well as serologic, genetic, and histopathologic data were collected. No significant differences were found between the two groups in most clinical variables, nor in the degree of intestinal lesion. However, the asymptomatic patients were taller (height z-score -0.12 (1.06) vs. -0.45 (1.19), p < 0.001) and were less likely to have anti transglutaminase IgA antibodies 10 times the upper normal limit (66.2% vs. 758.4%, p = 0.002). Among the 37.1% of asymptomatic patients who were not screened for CD due to the absence of risk factors, only 34% were truly asymptomatic, while the remaining 66% reported non-specific CD-related symptoms. Therefore, expanding CD screening to any child who undergoes a blood test could reduce the burden of care for some children, as many of those considered asymptomatic reported non-specific CD-related symptom

Whole Transcription Profile of Responders to Anti-TNF Drugs in Pediatric Inflammatory Bowel Disease

Background: Up to 30% of patients with pediatric inflammatory bowel disease (IBD) do not respond to anti-Tumor Necrosis Factor (anti-TNF) therapy. The aim of this study was to identify pharmacogenomic markers that predict early response to anti-TNF drugs in pediatric patients with IBD. Methods: An observational, longitudinal, prospective cohort study was conducted. The study population comprised 38 patients with IBD aged 0.6 or <−0.6 and p value < 0.05). After validation, FCGR1A, FCGR1B, and GBP1 were overexpressed in non-responders two weeks after initiation of anti-TNF treatment (Log2FC 1.05, 1.21, and 1.08, respectively, p value < 0.05). Conclusion: Expression of the FCGR1A, FCGR1B, and GBP1 genes is a pharmacogenomic biomarker of early response to anti-TNF agents in pediatric IBD.This research was funded by Instituto de Salud Carlos III (grants numbers PI16/00559 and PI19/00792), Consejería de Educación y Deporte de la Comunidad de Madrid (grant number PEJ16/MED/AI-1260), and by the Gregorio Marañón Health Research Institute (grant number PRE-2018-2). The study was cofunded by European Regional Develompment Funds (FEDER) from the European Commission, “A way of making Europe”.S