Association Between Inflammatory Bowel Diseases and Celiac Disease: A Systematic Review and Meta-Analysis

Review article: A practical approach to persistent gastrointestinal symptoms in inflammatory bowel disease in remission

BACKGROUND

Persistent gastrointestinal symptoms are prevalent in adult patients with inflammatory bowel disease (IBD), even when endoscopic remission is reached. These symptoms can have profound negative effects on the quality of life of affected patients and can be difficult to treat. They may be caused by IBD-related complications or comorbid disorders, but they can also be explained by irritable bowel syndrome (IBS)-like symptoms.

AIMS

To provide a practical step-by-step guide to diagnose and treat persistent gastrointestinal symptoms in patients with IBD in remission via a personalised approach.

METHODS

We scrutinised relevant literature on causes, diagnostics and treatment of persistent gastrointestinal symptoms (abdominal pain or discomfort, bloating, abdominal distension, diarrhoea, constipation and faecal incontinence) in patients with IBD in remission.

RESULTS

A graphical practical guide for several steps in diagnosing, identifying potential triggers and adequate treatment of persistent gastrointestinal symptoms in IBD in remission is provided based on supporting literature. The first part of this review focuses on the diagnostic and treatment approaches for potential IBD-related complications and comorbidities. The second part describes the approach to IBS-like symptoms in IBD in remission.

CONCLUSIONS

Persistent gastrointestinal symptoms in IBD in remission can be traced back to potential pathophysiological mechanisms in individual patients and can be treated adequately. For both IBD-related complications and comorbidities and IBS-like symptoms in IBD in remission, pharmacological, dietary, lifestyle or psychological treatments can be effective. A systematic and personalised approach is required to reduce the burden for patients, healthcare systems, and society.

Exploring the molecular mechanisms and shared gene signatures between celiac disease and ulcerative colitis based on bulk RNA and single-cell sequencing: Experimental verification

Many immune-mediated diseases have the common genetic basis, as an autoimmune disorder, celiac disease (CeD) primarily affects the small intestine, and is caused by the ingestion of gluten in genetically susceptible individuals. As for ulcerative colitis (UC), which most likely involves a complex interplay between some components of the commensal microbiota and other environmental factors in its origin. These two autoimmune diseases share a specific target organ, the bowel. The etiology and immunopathogenesis of both conditions characterized by chronic intestinal inflammation, ulcerative colitis and celiac disease, are not completely understood. Both are complex diseases with genetics and the environmental factors contributing to dysregulation of innate and adaptive immune responses, leading to chronic inflammation and disease. This study is designed to further clarify the relationship between UC and CeD. The GEO database was used to download gene expression profiles for CeD (GSE112102) and UC (GSE75214). The GSEA KEGG pathway analysis revealed that immune-related pathways were significantly associated with both diseases. Further, we screened 187 shared differentially expressed genes (DEGs) of the two diseases. Gene Ontology (GO) and WikiPathways were carried out to perform the biological process and pathway enrichment analysis. Subsequently, based on the DEGs, the least absolute shrinkage and selection operator (LASSO) analysis was performed to screen for the diagnostic biomarkers of the diseases. Moreover, single-cell RNA-sequencing (RNA-seq) data from five colonic propria with UC showed that REG4 expression was present in Goblet cell, Enteroendocrine cell, and Epithelial. Finally, our work identified REG4 is the shared gene of UC and CeD via external data validation, cellular experiments, and immunohistochemistry. In conclusion, our study elucidated that abnormal immune response could be the common pathogenesis of UC and CeD, and REG4 might be a key potential biomarker and therapeutic target for the comorbidity of these two diseases.

Children and Adolescents Diagnosed With Inflammatory Bowel Disease Are at Increased Risk of Developing Diseases With a Possible Autoimmune Pathogenesis

BACKGROUND

The development of diseases with a possible autoimmune pathogenesis is common in adults with inflammatory bowel disease (IBD). In early onset IBD, it may differ but the evidence is sparse. We aimed to investigate the risk and time span from IBD diagnosis to outcomes with different associated disorders with possible autoimmune pathogenesis.

METHODS

A register-based study included all Danish patients with early onset of IBD (≤18 years) between 1980 and 2021 and 50 matched references without IBD for each case. We examined the risk of type 1 and type 2 diabetes, celiac disease, thyroid disease, rheumatoid arthritis, psoriatic arthritis, and spondyloarthritis in Cox regression models.

RESULTS

In total, 6822 patients with IBD were identified, and 337 728 matched references. The median age at the time of IBD diagnosis or index date for the matched references was 16 years (25-75 percentile: 13-18 years), and the median age at the time of an outcome or at the end of follow-up was 28.1 years (25-75 percentile: 21.5-37.0 years). According to the cumulative incidence plots psoriatic arthritis, and spondyloarthritis was diagnosed approximately 10 years after the IBD onset, and the remaining outcomes later. The adjusted hazard ratio after full follow-up was 4.72 (95% CI, 3.85-5.80) for psoriatic arthritis, 5.21 (95% CI, 4.17-6.50) for spondyloarthritis, 2.77 (95% CI, 1.92-4.00) for celiac disease, 2.15 (95% CI, 1.54-3.01) for rheumatoid arthritis, 1.69 (95% CI, 1.23-2.32) and 1.64 (95% CI, 1.21-2.21) for type 1 and type 2 diabetes, respectively. For thyroid disease, it was 1.16 (95% CI, 0.97-1.40).

CONCLUSIONS

The risk estimates were significantly increased for all outcomes at the end of follow-up, except for thyroid disease, but according to the cumulative incidence plots, only psoriatic arthritis and spondyloarthritis occurred earlier in the IBD cohort than in the matched references.

The Role of Inflammatory Biomarkers in Mediating the Effect of Inflammatory Bowel Disease on nonmalignant Digestive System Diseases: A Multivariable Mendelian Randomized Study

Background

While observation studies have shown a positive correlation between inflammatory bowel disease (IBD) and the risk of nonmalignant digestive system diseases, a definitive causal relationship has not yet been clearly established.

Methods

Mendelian randomization (MR) was employed to investigate the potential causal association between genetic susceptibility to IBD and nonmalignant gastrointestinal diseases. Genetic variants were extracted as instrumental variables (IVs) from a genome-wide association study (GWAS) meta-analysis, which included 12,194 cases of Crohn's disease (CD) and 28,072 control cases of European ancestry. The GWAS for ulcerative colitis (UC) included 12,366 UC and 33,609 control cases of European ancestry. All IVs reached genome-wide significance (GWAS p value <5 × 10-8). Summary-level data for acute pancreatitis (AP), irritable bowel syndrome (IBS), gastroesophageal reflux disease, cholelithiasis, and CeD (celiac disease) were obtained from the GWAS meta-analysis and the FinnGen dataset. Summary-level data on relevant inflammatory factors were provided by the International Genetic Consortium. Univariate MR analysis was conducted using inverse variance weighting as the primary method for estimating causal effects. Multivariate MR analyses were also performed to detect possible mediators.

Results

Genetic susceptibility to UC was associated with an increased risk of AP (OR = 1.08; 95% CI = 1.03-1.13; p=0.002) and IBS odds ratio (OR] = 1.07; 95% confidence interval (CI] = 1.03-1.11; (p < 0.001). In terms of potential mediators, interleukin 6 (IL-6) had a driving effect on the association between UC and AP. There was no apparent evidence of increased risk with CD. Meanwhile, genetic susceptibility to CD increases the risk of CeD (OR = 1.14; 95% CI = 1.03-1.25; p=0.01).

Conclusions

The evidence suggests that UC is associated with an elevated risk of AP and IBS, and IL-6 may be responsible in AP. CD is associated with an increased risk of developing CeD. Implementing a proactive monitoring program for assessing the risk of gastrointestinal diseases in UC patients, particularly those with elevated IL-6 levels, may be of interest. In addition, the presence of AP and IBS may indicate the presence of UC. Preventing CeD is an essential consideration in the therapeutic management of patients with CD.

Celiac Disease-Related Conditions: Who to Test?

Celiac disease (CeD) is a chronic immune-mediated condition triggered by gluten consumption in genetically predisposed individuals. Approximately 1% of the general population is affected by the disorder. Disease presentation is heterogeneous and, despite growing awareness among physicians and the public, it continues to be underestimated. The most effective strategy for identifying undiagnosed CeD is proactive case finding through serologic testing in high-risk groups. We reviewed the most recent evidence on the association between CeD and more than 20 conditions. In light of this review, CeD screening is recommended in individuals with (1) autoimmune disease and accompanying symptoms suggestive of CeD; (2) diseases that may mimic CeD (eg, irritable bowel syndrome [IBS], inflammatory bowel disease [IBD], and microscopic colitis); and (3) among patients with conditions with a high CeD prevalence: first-degree relatives, idiopathic pancreatitis, unexplained liver enzyme abnormalities, autoimmune hepatitis, primary biliary cholangitis, hyposplenism or functional asplenia with severe bacterial infection, type 1 diabetes mellitus, Hashimoto's thyroiditis and Graves' disease, Sjögren's syndrome, dermatitis herpetiformis, recurrent aphthous syndrome and enamel defects, unexplained ataxia, peripheral neuropathy, delayed menarche or premature menopause, Down syndrome, Turner syndrome, Williams syndrome, chronic fatigue syndrome, IgA nephropathy, and IgA deficiency. CeD serology should be the initial step in the screening process. However, for patients with any of the aforementioned disorders who are undergoing upper endoscopy, biopsies should be performed to rule out CeD.

Older age of celiac disease diagnosis and risk of autoimmune disease: A nationwide matched case-control study

OBJECTIVES

Celiac disease (CeD) has been linked to an increased risk of other autoimmune diseases, yet the impact of delayed CeD diagnosis on risk of developing additional autoimmune diseases remains uncertain. We investigated this through a nationwide matched case-control study.

METHODS

Using the ESPRESSO cohort with histophatology data from Sweden's 28 pathology departments, we assessed 46,575 biopsy-confirmed CeD cases from 1964 to 2017. We extracted 225,295 matched controls without histopathology information from the Swedish Total Population Register. Autoimmune disease was defined through diagnostic codes in the National Patient Register. Through conditional logistic regression we estimated odds ratio (OR) of autoimmune disease up until CeD diagnosis/matching date comparing CeD cases to controls across different age strata.

RESULTS

A total of 3059 (6.6 %) CeD patients and 4076 (1.8 %) controls had earlier autoimmune disease. The overall OR for autoimmune disease in CeD was 3.50 (95%CI 3.32-3.70). The risk of autoimmune disease did not escalate with increasing age at CeD diagnosis. Compared with controls, the OR of autoimmune disease in CeD patients was 7.70 (95%CI 4.71-12.57) in those diagnosed with CeD in 0-4 years, 19.02 (95%CI 13.80-26.23) in 5-9 years, 6.18 (95%CI 5.14-7.44) in 10-14 years, 4.80 (95%CI 3.97-5.79) in 15-19 years, 4.24 (95%CI 3.55-5.07) in 20-29 years, 4.65 (95%CI 3.93-5.51) in 30-39 years, 3.67 (95%CI 3.30-4.09) in 40-59 years, and 1.67 (95%CI 1.50-1.85) in ≥60 years.

CONCLUSIONS

This study revealed an increased risk of autoimmune disease among CeD patients compared with controls. However, older age at CeD diagnosis did not seem to escalate the risk of autoimmune diseases.

Performance Assessment of a Novel Multianalyte Methodology for Celiac Disease Biomarker Detection and Evaluation of the Serology-Alone Criteria for Biopsy-Free Diagnosis

CONTEXT.—

Serology plays a vital role in celiac disease (CD) diagnosis, and the latest European guidelines advocate for biopsy-free diagnoses in patients with ≥10× the upper limit of normal (ULN) of anti-tissue transglutaminase (tTG) immunoglobulin A (IgA) antibodies.

OBJECTIVE.—

To assess performance characteristics of a novel automated particle-based multianalyte technology (Aptiva) for anti-tTG and anti-deamidated gliadin peptide (DGP) antibody detection as compared to the traditional enzyme-linked immunosorbent assay (QUANTA Lite). Performance characteristics of the ≥10× ULN anti-tTG IgA criteria for serologic diagnosis of CD were also evaluated.

DESIGN.—

Sera samples from 703 patients were tested for anti-tTG IgA, anti-tTG immunoglobulin G (IgG), anti-DGP IgA, and anti-DGP IgG antibodies on both platforms. In total, 127 patients had medical information and were classified as CD-positive (n = 58) and CD-negative (n = 69) based on biopsy results. Clinical performance characteristics were evaluated.

RESULTS.—

Anti-tTG IgA detection showed equal clinical sensitivity and specificity of 91% sensitivity and 99% specificity on both platforms. Anti-tTG IgG resulted in moderate sensitivity of 69% and 72%, but high specificity of 100% and 94% on Aptiva and QUANTA Lite, respectively. Anti-DGP IgG displayed comparable sensitivity of 90% and 81%, and a specificity of 94% and 99%, on Aptiva and QUANTA Lite, respectively. Anti-DGP IgA demonstrated greater sensitivity on QUANTA Lite (83%) than Aptiva (69%) and similar specificities of 97% and 98% on QUANTA Lite and Aptiva, respectively. At ≥10× ULN levels for anti-tTG IgA, Aptiva displayed a sensitivity of 72% and a specificity of 100%, and QUANTA Lite showed a sensitivity of 69% and a specificity of 100%.

CONCLUSIONS.—

Aptiva is a reliable method to measure CD biomarkers with reduced hands-on necessity and high-throughput capabilities. This study supports the use of a ≥10× ULN anti-tTG IgA biopsy-free approach for serologic diagnosis of CD.

Prevalence of markers of beta cell autoimmunity and thyroid disease in children with coeliac disease

BACKGROUND

Over the last decades, the prevalence of coeliac disease (CD), an autoimmune disorder, rose to 1-2%. Whether patients with CD have higher risk of developing other autoimmune disorders such as type 1 diabetes, Hashimoto thyroiditis, or Graves` disease remains unclear.

AIM

The aim of this study was to determine the prevalence of biomarkers of beta cell and thyroid autoimmunity in children with CD.

METHODS

Retrospective cross-sectional cohort study comparing pediatric patients suffering from CD with age and sex-matched healthy controls (HC). Participant`s serum was tested by immunoassay for following autoantibodies (aAb): TSH-receptor antibodies (TRAb), anti-thyroglobulin (anti-Tg), anti-thyroid peroxidase (anti-TPO), anti-glutamic acid decarboxylase (anti-GAD), anti-zinc transporter 8 (anti-ZnT8), anti-islet antigen 2 (anti-IA2) and anti-insulin.

RESULTS

A total of 95 patients with CD (mean age 8.9 years; 63% female) and 199 matched healthy controls (mean age 9.2 years; 59.8% female) were included in the study. For patients with CD, a seroprevalence of 2.1% (vs. 1.5% in HC) was calculated for anti-GAD, 1.1% for anti-IA2 (vs. 1.5% in HC), 3.2% for anti-ZnT8 (vs. 4.2% in HC), and 1.1% (vs. 1% in HC) for anti-insulin. For thyroid disease, a seroprevalence of 2.2% for TRAb (vs. 1% in HC), 0% for anti-TPO (vs. 2.5% in HC) and 4.3% for anti-Tg (vs. 3.5% in HC) was found for patients with CD.

CONCLUSION

This study suggests a higher prevalence of autoimmune antibodies againstthyroid in children with CD compared to HC, whilst it is similar for pancreatic antibodies. Prospective cohort studies are needed to first evaluate the occurrence of autoimmune antibodies against beta cells and thyroid over a longer follow-up time and second to explore their clinical relevance.

The Gluten-Free Diet for Celiac Disease: Critical Insights to Better Understand Clinical Outcomes

The gluten-free diet (GFD) remains a complex paradigm in managing celiac disease (CeD) in children and adults, and there are many reasons why GFD adherence should be strict to improve outcomes. However, this is a challenging task for patients, since they need to have access to quality healthcare resources that facilitate optimal GFD adherence. Understanding the strengths and weaknesses of the GFD, tackling coexisting nutritional deficiencies, and dealing with complex situations, such as seronegative CeD or non-responsive CeD, all require the involvement of a multidisciplinary team. The short- and long-term follow-up of CeD patients should preferably be performed by a combined Gastroenterology and Nutrition service with well-defined quality standards and the multidisciplinary involvement of physicians, nurses, dietitians, and psychologists. Nutritional advice and counseling by an experienced dietitian can reduce the costs associated with long-term follow-up of CeD patients. Likewise, psychological interventions may be essential in specific scenarios where implementing and sustaining a lifelong GFD can cause a significant psychological burden for patients. This manuscript aims to provide guidelines to improve clinical practice in the follow-up and monitoring of CeD patients and provide information on the nutritional risks of an ill-advised GFD. Clinicians, biochemists, food technologists, dietitians, and psychologists with a global view of the disease have been involved in its writing.

Protection from inflammatory bowel disease

Immunomodulation of lymphocytes by intestinal epithelial cells could lead to new therapies.

Population-Based Screening for Coeliac Disease in Lithuanian Children from 2009 to 2014

Background and Objectives. Coeliac disease is an autoimmune disorder provoked by a dietary group of proteins called gluten in genetically predisposed individuals. Over the past several decades, the prevalence of coeliac disease has been steadily growing and it is now recognized to be occurring worldwide. The prevalence varies greatly between ethnic, racial groups and regionally. Such variability makes local epidemiological studies important for spreading awareness and setting a threshold for suspicion of coeliac disease. We explored the potential application of a quick point-of-care test for the purpose of detecting a presence of IgA class TG2 antibodies for coeliac disease and screening in a Lithuanian pediatric population. Previously, there were no data regarding coeliac disease prevalence in Lithuania. Materials and Methods. Overall, we included 1458 children 11-13 years of age from several Lithuanian schools selected randomly in this study. Utilizing one point-of-care test using a single blood sample taken from a fingertip, we identified the existence of IgA class TG2 antibodies. Only children whose parents gave consent were enrolled in the study. Those with positive IgA class TG2-ab were directed to a tertiary hospital for additional clinical assessment and confirmation of suspected coeliac disease. Results. A total of two (0.14%) of the 1458 enrolled children were detected with the presence of TG2 antibodies and the coeliac disease diagnosis was further confirmed with histological examination of duodenal biopsy samples. Additionally, we checked that patients had not previously reported any clinical symptoms and signs that could suggest coeliac disease or any other disease of the gastrointestinal tract. Conclusions. The detected prevalence of coeliac disease in the Lithuanian pediatric population is 1:729. The rapid finger prick test for the presence of IgA class TG2 antibodies is a reasonable and accurate method to screen for celiac disease in children.

Increased Risk of Celiac Disease in Patients with Uveitis

PURPOSE

To examine whether patients with non-infectious uveitis (NIU) are at increased risk for celiac disease (CeD).

METHODS

Celiac antibody testing was completed in 112 patients. The control group included patients who had undergone upper endoscopy for suspicion of CeD.

RESULTS

2/112 (1.79%) of patients with NIU had positive anti-tTG serology and CeD was confirmed in both patients. When compared to the expected risk of CeD in the general Israeli population of 0.31%, this corresponded to an odds ratio of 5.77 (95% CI 1.4118 to 23.4737, P = 0.049). Three additional patients had positive serology for CeD but the diagnosis was not confirmed.

CONCLUSIONS

An increased risk of CeD was detected in patients with NIU. We therefore recommend screening for CeD in NIU patients. Larger prospective studies are required to further validate these results.

"Brunner gland inflammation in Crohn's disease and Celiac disease: Overlapping inflammatory patterns suggest a possible link"

Similar to celiac disease, inflammatory bowel disease frequently manifests in the duodenum. Histopathologic studies focused on mucosal alterations with little attention to submucosal Brunner glands. Recently, several studies have demonstrated overlapping features between Crohn's disease and celiac disease suggesting a putative link. However, histopathologic studies evaluating this possible link are limited, and those that are focused on Brunner glands are lacking. The present study aims to explore whether Crohn's disease and celiac disease display shared or overlapping inflammatory changes in Brunner glands. We performed a retrospective review study over 17-years retrieving duodenal biopsy specimens containing Brunner gland lobules in patients with Crohn's disease, celiac disease, and ulcerative colitis. We found 10 out of 126 duodenal biopsies (8 %) in patients with Crohn's disease and 6 out of 134 (4.5 %) duodenal biopsies in patients with celiac disease sharing inflammatory patterns in duodenal Brunner gland lobules. Both diseases showed interstitial intralobular and interlobular mixed chronic inflammation with variable fibrosis. Focally enhanced active inflammation of Brunner gland lobules was more characteristic of Crohn's disease. Intralobular epithelioid granulomas and multinucleated giant cells were specific to Crohn's disease. Ulcerative colitis patients did not show similar features. The interstitial focally enhanced chronic inflammatory pattern was significantly (p < 0.05) associated with both diseases, while the other inflammatory patterns were not (p > 0.05). This overlapping inflammatory pattern in Brunner glands in patients with Crohn's disease and celiac disease is supportive of the previously reported link between the two diseases. Pathologists should pay more attention to Brunner glands when evaluating duodenal biopsies. Further studies are warranted to validate these observations and their relevance in the pathogenesis of autoinflammatory gastrointestinal diseases.

ESPEN guideline on Clinical Nutrition in inflammatory bowel disease

The present guideline is an update and extension of the ESPEN scientific guideline on Clinical Nutrition in Inflammatory Bowel Disease published first in 2017. The guideline has been rearranged according to the ESPEN practical guideline on Clinical Nutrition in Inflammatory Bowel Disease published in 2020. All recommendations have been checked and, if needed, revised based on new literature, before they underwent the ESPEN consensus procedure. Moreover, a new chapter on microbiota modulation as a new option in IBD treatment has been added. The number of recommendations has been increased to 71 recommendations in the guideline update. The guideline is aimed at professionals working in clinical practice, either in hospitals or in outpatient medicine, and treating patients with IBD. General aspects of care in patients with IBD, and specific aspects during active disease and in remission are addressed. All recommendations are equipped with evidence grades, consensus rates, short commentaries and links to cited literature.

Case-control study of the concurrence of coeliac disease with inflammatory bowel disease

BACKGROUND AND AIMS

Previous studies suggested that inflammatory bowel disease (IBD) is associated with an increased prevalence of comorbid coeliac disease. Our case-control study aimed to test this association using a large histopathology database.

METHODS

The Inform Diagnostics database is a repository of histopathologic records from patients distributed throughout the United States. In a case-control study among patients with bidirectional endoscopy, we compared the occurrence of coeliac disease in case subjects with IBD or microscopic colitis (MC) and control subjects without inflammatory colitis, calculating odds ratios (OR) and their 95% confidence intervals (CI) adjusted to the varying age, gender and ethnic distributions of case and control subjects.

RESULTS

The study population was split into 12,816 IBD cases and 6486 MC cases, who were compared to 345,733 control subjects without colitis. A total of 2892 patients were diagnosed with coeliac disease. Of 12,816 IBD patients, 57 patients (0.4%) harboured coeliac disease compared to 0.7% (2548/345,733) in the control population. The prevalence of coeliac disease among MC patients was 4.4% (288/6486). The corresponding ORs were significantly decreased in IBD (OR: 0.50, CI: 0.38-0.64) and significantly increased in MC patients (6.78, 5.96-7.69). Further stratification of the case populations into subtypes of IBD (Crohn's disease or ulcerative colitis) and MC (collagenous or lymphocytic colitis) similarly revealed significantly decreased and increased ORs for each subtype.

CONCLUSIONS

The previously reported positive association between coeliac disease and IBD may have been possibly biased by the inclusion of MC cases in the IBD patient population.

Human glycoprotein-2 expressed in Brunner glands - A putative autoimmune target and link between Crohn's and coeliac disease

Glycoprotein 2 (GP2) is an autoantigen in Crohn's (CD) and coeliac disease (CeD). We assessed GP2-isoform (GP2_1-4)-expression in intestinal biopsies of paediatric patients with CD, CeD, ulcerative colitis (UC), and healthy children (HC). Transcription of GP2_1-4 was elevated in proximal small intestine in CeD and CD patients (only GP2_2/4) compared to jejunum (CeD/CD) and large bowel (CD). CeD patients demonstrated higher duodenal GP2_2/4-mRNA levels compared to HC/UC patients whereas CD patients showed higher GP2₄-mRNA levels compared to UC patients. Duodenal synthesis of only small GP2 isoforms (GP2_3/4) was demonstrated in epithelial cells in patients/HC and in Brunner glands (also large isoforms) with a more frequent apical location in CD/CeD patients. All four GP2 isoforms interacted with gliadin and phosphopeptidomannan. Gliadin digestion improved binding to GP2 isoforms. GP2_1-4 binding to CeD/CD-related antigens, elevated duodenal GP2_1-4-mRNA transcription, and GP2-protein secretion in Brunner glands of CeD/CD patients suggest an autoimmune CeD/CD link.

Causal association between celiac disease and inflammatory bowel disease: A two-sample bidirectional Mendelian randomization study

Background

An epidemiological link between celiac disease (CeD) and inflammatory bowel disease (IBD) has been well established recently. In this study, Mendelian randomization (MR) analysis was performed employing pooled data of publicly available genome-wide association studies (GWAS) to determine the causal relationship between CeD and IBD, encompassing ulcerative colitis (UC) and Crohn's disease (CD).

Methods

Dataset of CeD was acquired from GWAS for 12,041 cases and 12,228 controls. A GWAS of more than 86,000 patients and controls was used to identify genetic variations underlying IBD. MR analyses were performed with an inverse-variance-weighted approach, an MR-Egger regression, a weighted-mode approach, a weighted-median method, and sensitivity analyses of MR pleiotropy residual sum and outlie (MR-PRESSO).

Results

MR demonstrated that genetic predisposition to CeD was linked to a augmented risk of IBD (OR: 1.1408; 95% CI: 1.0614-1.2261; P = 0.0003). In the analysis of the two IBD subtypes, genetic predisposition to CeD was also linked to increased risks of UC (OR: 1.1646; 95% CI: 1.0614-1.2779; P = 0.0012) and CD (OR: 1.1865; 95% CI: 1.0948-1.2859; P = 3.07E-05). Reverse MR analysis results revealed that genetic susceptibility to IBD and CD was correlated with an augmented risk of CeD. However, there was no genetic correlation between UC and CeD. All of the above results were validated with other GWAS databases.

Conclusion

There is a bidirectional causal relationship of CeD with IBD and CD. However, UC only augments the risk of developing CeD.

User testing to modify the MyHealthyGut digital health application for inflammatory bowel disease

Introduction

Inflammatory bowel disease, characterized by chronic intestinal inflammation, can be subcategorized into Crohn's disease and ulcerative colitis. The treatment for these conditions is unique to each patient and may include lifestyle changes, pharmaceutical intervention, and surgery. Lifestyle changes, such as dietary intervention, are a cornerstone of inflammatory bowel disease symptom management. Given the daily burden of this disease, self-management is paramount in coping with and/or minimizing symptoms. The MyHealthyGut application, successfully proven to be a self-management tool for celiac disease, shows promise for use in an inflammatory bowel disease patient population.

Objective

To conduct user testing to gather valuable insights for the development of an IBD-focused version of the existing MyHealthyGut app.

Methods

Participants included inflammatory bowel disease patients and healthcare practitioners. Participants used the application for a 2-week period, followed by participation in a focus group or individual interview to provide feedback. Qualitative questionnaires were administered verbally and feedback was recorded. Thematic analysis techniques were used for data quantification and analysis.

Results

15 participants were recruited and enrolled. Of these, 14 participants took part in the focus group and/or individual interviews. The feedback suggested changes related to clinical uses, food and symptom tracking, ease of use, and educational content. All (100%) participants reported that they would either use the application themselves or recommend it to patients, once their suggestions were implemented.

Conclusion

Through user testing and feedback collection, priorities for app modification were identified. Areas for modification in the app functions and features, ease of use, and content were identified. Once updated to meet the needs of inflammatory bowel disease patients, the MyHealthyGut app may be a useful tool for IBD self-management.

Replacing the Burden of the Gluten Free Diet: Then, Now, and the Future

Without a doubt, a majority of diseases are food-pattern-related. However, one disease stands out as an increasingly more common autoimmune-mediated enteropathy triggered by the ingestion of gluten. Celiac disease (CD) is an old disease, with changing clinical patterns, affecting any age, including infancy and adolescence, and becoming more frequent among the elderly. The gluten-free diet (GFD) has been the sole provider of clinical, serological, and histological improvement for patients with CD for more than seven decades. Nowadays, complete avoidance of dietary gluten is rarely possible because of the wide availability of wheat and other processed foods that contain even more gluten, to the detriment of gluten-free products. Undeniably, there is a definite need for replacing the burdensome GFD. An add-on therapy that could control the dietary transgressions and inadvertent gluten consumption that can possibly lead to overt CD should be considered while on GFD. Nevertheless, future drugs should be able to provide patients some freedom to self-manage CD and increase food independence, while actively reducing exposure and mucosal damage and alleviating GI symptoms. Numerous clinical trials assessing different molecules have already been performed with favorable outcomes, and hopefully they will soon be available for patient use.

Characteristics of Children With Inflammatory Bowel Disease and Coexisting Celiac Disease Seropositivity

OBJECTIVES

Celiac disease (CeD) autoimmunity and coexisting inflammatory bowel disease (IBD) present a diagnostic dilemma. Our aims were to describe the phenotype of children with IBD and CeD seropositivity and evaluate provider confidence for diagnosing CeD in this population.

METHODS

We performed a single-center retrospective cohort study of subjects ≤18 years old with IBD and CeD seropositivity between 2006 and 2020. Subjects were considered to have IBD-CeD if they met CeD diagnosis by serology and histology per North American Society For Pediatric Gastroenterology, Hepatology and Nutrition guidelines and if providers suspected CeD as evaluated by a survey. The IBD-only cohort included seropositive participants that did not meet criteria for CeD. Demographic, histologic, gross endoscopic, and laboratory features were compared using Fisher exact test.

RESULTS

Of 475 children with IBD, 8 had concomitant CeD, 5 had tissue transglutaminase (tTG) immunoglobulin A (IgA) > 10x upper limit of normal (ULN, P = 0.006), and 8 had villous atrophy (VA, P = 0.003) when compared with 17 seropositive participants with IBD-only. No children with IBD-CeD had esophageal eosinophilia, duodenal cryptitis, duodenal ulceration, or fecal calprotectin >250 µg/g. Factors that contributed to provider uncertainty for diagnosing CeD in IBD included the absence of VA and intraepithelial lymphocytes, the presence of neutrophilic and eosinophilic duodenitis, diffuse ulceration, elevated inflammatory markers, and immunosuppression therapy.

CONCLUSIONS

Diagnosing CeD in children with IBD continues to be challenging. Although high titers of tTG IgA and VA increased provider confidence for diagnosing CeD in IBD, development of evidence-based guidelines are needed. They should better assess the importance of features atypical of concomitant CeD that contribute to uncertainty.

The association of Inflammatory Bowel Disease with Celiac Disease and Celiac Autoimmunity in children and adults: A nationwide study from the epi-IIRN

BACKGROUND AND AIMS

Given the paucity of population-based data on the association between inflammatory bowel diseases (IBD), celiac disease (CeD) and celiac autoimmunity (CeA) we aimed to study the associations in a nationwide study.

METHODS

Utilizing health administrative data for all four health maintenance organizations in Israel, covering 98% of the population, we explored the prevalence of CeD in children and adults with IBD versus non-IBD matched controls. CeD was defined by three ICD-9 codes and CeA by positivity for tissue transglutaminase antibodies.

RESULTS

In total, 34,375 IBD patients (56% Crohn's disease [CD] and 44% ulcerative colitis [UC]) were compared with 93,603 non-IBD controls. Among IBD patients, 319 (0.93%) had CeD versus 294 (0.31%) non-IBD controls (odds ratio [OR]=2.97 [95%CI 2.54-3.48]; p<0.001). CeA was identified in 575 (1.67%) IBD patients vs. 158 (0.17%) controls (OR=10.06 [95%CI 8.43-12], p<0.001). The prevalence of CeD was higher in pediatric-onset IBD (87/5,243 [1.66%]) than adult-onset IBD (232/29,132 [0.79%]; p<0.001). CD patients had a higher prevalence of CeD (229/19,264 [1.19%]) than UC patients (90/15,111 [0.56%]; OR=2.01 [95%CI 1.57-2.56]; p<0.001). The diagnosis of CeD preceded the diagnosis of IBD in 241/319 cases (76%). The time to treatment escalation was shorter in patients with both IBD and CeD than in patients with IBD without CeD (p=0.017).

CONCLUSION

CeD and CeA are more prevalent in IBD patients, especially in pediatric-onset IBD and in CD. The diagnosis of CeD usually precedes that of IBD. Having CeD is associated with more intensified treatment for IBD.

A broad cuproptosis landscape in inflammatory bowel disease

Background

Cuproptosis, a genetic process of copper-dependent cell death linked to mitochondria respiration, demonstrates its correlation with inhibiting tumoral angiogenesis and motility. Recent studies have developed systematic bioinformatics frameworks to identify the association of cuproptosis with tumors but any non-neoplastic diseases. Therefore, against the background of an increased incidence of inflammatory bowel disease (IBD), the landscape of cuproptosis regulation in IBD is a critical need to be investigated.

Methods

The differentially expressed cuproptosis-related genes (DECRGs) were identified with human sequencing profiles for four inflammatory digestive disorders. Another four independent IBD datasets from GEO were used as a validation cohort. And experimental mice model provides another validation method. Using single sample gene set enrichment analysis (ssGSEA), receiver operating characteristic (ROC) curve, CIBERSORT, and consensus clustering algorithms, we explored the association between immune score and cuproptosis-related genes, as well as the diagnostic value of these genes. Molecular docking screened potential interaction of IBD drugs with the structural regulator by Autodock Vina.

Results

Cuproptosis-related regulators exhibited extensive differential expression in Crohn's Disease (CD), Ulcerative Colitis (UC), Celiac Disease (CEL), and IBD-induced cancer (IBD-CA) that share common differential genes (PDHA1, DBT, DLAT, LIAS). The differential expression of DECRGs was reverified in the validated cohort and immunohistochemistry assay. Moreover, the cell signaling pathways and ontology mainly focused on the mitochondrial respiratory function, which was highly enriched in Gene set enrichment analysis (GSEA). According to ssGSEA and ROC, when considering the four regulators, which showed robust association with immune infiltration in IBD, the area under the ROC (AUC) was 0.743. In addition, two clusters of consensus clustering based on the four regulators exhibit different immune phenotypes. According to molecular docking results, methotrexate gained the highest binding affinity to the main chain of key cuproptosis-related regulators compared with the remaining ten drugs.

Conclusion

Cuproptosis-related regulators were widely linked to risk variants, immune cells, immune function, and drug efficacy in IBD. Regulation of cuproptosis may deeply influence the occurrence and development of patients with IBD.

AGA Clinical Practice Update on Management of Refractory Celiac Disease: Expert Review

DESCRIPTION

The purpose of this expert review is to summarize the diagnosis and management of refractory celiac disease. It will review evaluation of patients with celiac disease who have persistent or recurrent symptoms, differential diagnosis, nutritional support, potential therapeutic options, and surveillance for complications of this condition.

METHODS

This expert review was commissioned and approved by the American Gastroenterological Association (AGA) Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. These Best Practice Advice (BPA) statements were drawn from a review of the published literature and from expert opinion. Since systematic reviews were not performed, these BPA statements do not carry formal ratings of the quality of evidence or strength of the presented considerations. Best Practice Advice Statements BEST PRACTICE ADVICE 1: In patients believed to have celiac disease who have persistent or recurrent symptoms or signs, the initial diagnosis of celiac disease should be confirmed by review of prior diagnostic testing, including serologies, endoscopies, and histologic findings. BEST PRACTICE ADVICE 2: In patients with confirmed celiac disease with persistent or recurrent symptoms or signs (nonresponsive celiac disease), ongoing gluten ingestion should be excluded as a cause of these symptoms with serologic testing, dietitian review, and detection of immunogenic peptides in stool or urine. Esophagogastroduodenoscopy with small bowel biopsies should be performed to look for villous atrophy. If villous atrophy persists or the initial diagnosis of celiac disease was not confirmed, consider other causes of villous atrophy, including common variable immunodeficiency, autoimmune enteropathy, tropical sprue, and medication-induced enteropathy. BEST PRACTICE ADVICE 3: For patients with nonresponsive celiac disease, after exclusion of gluten ingestion, perform a systematic evaluation for other potential causes of symptoms, including functional bowel disorders, microscopic colitis, pancreatic insufficiency, inflammatory bowel disease, lactose or fructose intolerance, and small intestinal bacterial overgrowth. BEST PRACTICE ADVICE 4: Use flow cytometry, immunohistochemistry, and T-cell receptor rearrangement studies to distinguish between subtypes of refractory celiac disease and to exclude enteropathy-associated T-cell lymphoma. Type 1 refractory celiac disease is characterized by a normal intraepithelial lymphocyte population and type 2 is defined by the presence of an aberrant, clonal intraepithelial lymphocyte population. Consultation with an expert hematopathologist is necessary to interpret these studies. BEST PRACTICE ADVICE 5: Perform small bowel imaging with capsule endoscopy and computed tomography or magnetic resonance enterography to exclude enteropathy-associated T-cell lymphoma and ulcerative jejunoileitis at initial diagnosis of type 2 refractory celiac disease. BEST PRACTICE ADVICE 6: Complete a detailed nutritional assessment with investigation of micronutrient and macronutrient deficiencies in patients diagnosed with refractory celiac disease. Check albumin as an independent prognostic factor. BEST PRACTICE ADVICE 7: Correct deficiencies in macro- and micronutrients using oral supplements and/or enteral support. Consider parenteral nutrition for patients with severe malnutrition due to malabsorption. BEST PRACTICE ADVICE 8: Corticosteroids, most commonly open-capsule budesonide or, if unavailable, prednisone, are the medication of choice and should be used as first-line therapy in either type 1 or type 2 refractory celiac disease. BEST PRACTICE ADVICE 9: Patients with refractory celiac disease require regular follow-up by a multidisciplinary team, including gastroenterologists and dietitians, to assess clinical and histologic response to therapy. Identify local experts with expertise in celiac disease to assist with management. BEST PRACTICE ADVICE 10: Patients with refractory celiac disease without response to steroids may benefit from referral to a center with expertise for management or evaluation for inclusion in clinical trials.

Defining the optimum strategy for identifying adults and children with coeliac disease: systematic review and economic modelling

BACKGROUND

Coeliac disease is an autoimmune disorder triggered by ingesting gluten. It affects approximately 1% of the UK population, but only one in three people is thought to have a diagnosis. Untreated coeliac disease may lead to malnutrition, anaemia, osteoporosis and lymphoma.

OBJECTIVES

The objectives were to define at-risk groups and determine the cost-effectiveness of active case-finding strategies in primary care.

DESIGN

(1) Systematic review of the accuracy of potential diagnostic indicators for coeliac disease. (2) Routine data analysis to develop prediction models for identification of people who may benefit from testing for coeliac disease. (3) Systematic review of the accuracy of diagnostic tests for coeliac disease. (4) Systematic review of the accuracy of genetic tests for coeliac disease (literature search conducted in April 2021). (5) Online survey to identify diagnostic thresholds for testing, starting treatment and referral for biopsy. (6) Economic modelling to identify the cost-effectiveness of different active case-finding strategies, informed by the findings from previous objectives.

DATA SOURCES

For the first systematic review, the following databases were searched from 1997 to April 2021: MEDLINE® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), Cochrane Library, Web of Science™ (Clarivate™, Philadelphia, PA, USA), the World Health Organization International Clinical Trials Registry Platform ( WHO ICTRP ) and the National Institutes of Health Clinical Trials database. For the second systematic review, the following databases were searched from January 1990 to August 2020: MEDLINE, Embase, Cochrane Library, Web of Science, Kleijnen Systematic Reviews ( KSR ) Evidence, WHO ICTRP and the National Institutes of Health Clinical Trials database. For prediction model development, Clinical Practice Research Datalink GOLD, Clinical Practice Research Datalink Aurum and a subcohort of the Avon Longitudinal Study of Parents and Children were used; for estimates for the economic models, Clinical Practice Research Datalink Aurum was used.

REVIEW METHODS

For review 1, cohort and case-control studies reporting on a diagnostic indicator in a population with and a population without coeliac disease were eligible. For review 2, diagnostic cohort studies including patients presenting with coeliac disease symptoms who were tested with serological tests for coeliac disease and underwent a duodenal biopsy as reference standard were eligible. In both reviews, risk of bias was assessed using the quality assessment of diagnostic accuracy studies 2 tool. Bivariate random-effects meta-analyses were fitted, in which binomial likelihoods for the numbers of true positives and true negatives were assumed.

RESULTS

People with dermatitis herpetiformis, a family history of coeliac disease, migraine, anaemia, type 1 diabetes, osteoporosis or chronic liver disease are 1.5-2 times more likely than the general population to have coeliac disease; individual gastrointestinal symptoms were not useful for identifying coeliac disease. For children, women and men, prediction models included 24, 24 and 21 indicators of coeliac disease, respectively. The models showed good discrimination between patients with and patients without coeliac disease, but performed less well when externally validated. Serological tests were found to have good diagnostic accuracy for coeliac disease. Immunoglobulin A tissue transglutaminase had the highest sensitivity and endomysial antibody the highest specificity. There was little improvement when tests were used in combination. Survey respondents (n = 472) wanted to be 66% certain of the diagnosis from a blood test before starting a gluten-free diet if symptomatic, and 90% certain if asymptomatic. Cost-effectiveness analyses found that, among adults, and using serological testing alone, immunoglobulin A tissue transglutaminase was most cost-effective at a 1% pre-test probability (equivalent to population screening). Strategies using immunoglobulin A endomysial antibody plus human leucocyte antigen or human leucocyte antigen plus immunoglobulin A tissue transglutaminase with any pre-test probability had similar cost-effectiveness results, which were also similar to the cost-effectiveness results of immunoglobulin A tissue transglutaminase at a 1% pre-test probability. The most practical alternative for implementation within the NHS is likely to be a combination of human leucocyte antigen and immunoglobulin A tissue transglutaminase testing among those with a pre-test probability above 1.5%. Among children, the most cost-effective strategy was a 10% pre-test probability with human leucocyte antigen plus immunoglobulin A tissue transglutaminase, but there was uncertainty around the most cost-effective pre-test probability. There was substantial uncertainty in economic model results, which means that there would be great value in conducting further research.

LIMITATIONS

The interpretation of meta-analyses was limited by the substantial heterogeneity between the included studies, and most included studies were judged to be at high risk of bias. The main limitations of the prediction models were that we were restricted to diagnostic indicators that were recorded by general practitioners and that, because coeliac disease is underdiagnosed, it is also under-reported in health-care data. The cost-effectiveness model is a simplification of coeliac disease and modelled an average cohort rather than individuals. Evidence was weak on the probability of routine coeliac disease diagnosis, the accuracy of serological and genetic tests and the utility of a gluten-free diet.

CONCLUSIONS

Population screening with immunoglobulin A tissue transglutaminase (1% pre-test probability) and of immunoglobulin A endomysial antibody followed by human leucocyte antigen testing or human leucocyte antigen testing followed by immunoglobulin A tissue transglutaminase with any pre-test probability appear to have similar cost-effectiveness results. As decisions to implement population screening cannot be made based on our economic analysis alone, and given the practical challenges of identifying patients with higher pre-test probabilities, we recommend that human leucocyte antigen combined with immunoglobulin A tissue transglutaminase testing should be considered for adults with at least a 1.5% pre-test probability of coeliac disease, equivalent to having at least one predictor. A more targeted strategy of 10% pre-test probability is recommended for children (e.g. children with anaemia).

FUTURE WORK

Future work should consider whether or not population-based screening for coeliac disease could meet the UK National Screening Committee criteria and whether or not it necessitates a long-term randomised controlled trial of screening strategies. Large prospective cohort studies in which all participants receive accurate tests for coeliac disease are needed.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42019115506 and CRD42020170766.

FUNDING

This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 44. See the NIHR Journals Library website for further project information.

Bidirectional causal link between inflammatory bowel disease and celiac disease: A two-sample mendelian randomization analysis

Background: Observational research has shown a correlation between inflammatory bowel disease (IBD) [comprising ulcerative colitis (UC) and Crohn’s disease (CD)] and celiac disease. However, the relationship between these two diseases remains uncertain.

Methods: We utilized two-sample Mendelian randomization (MR) to estimate the bidirectional causal relationships between IBD and celiac disease. This study utilized data on single nucleotide polymorphisms (SNPs) from genome-wide association studies (GWASs). Heterogeneity, pleiotropy, and sensitivity analyses were also performed to evaluate the MR results.

Results: There was a significant causal relationship between IBD and CD and celiac disease (e.g., IBD and celiac disease, inverse variance weighting (IVW) odds ratio (OR) = 1.0828, 95% CI = 1.0258–1.1428, p = 0.0039; CD and celiac disease, IVW OR = 1.0807, 95% CI = 1.0227–1.1420, p = 0.0058). However, in the reverse direction, we found only suggestive positive causality between celiac disease and CD (e.g., IVW OR = 1.0366, 95% CI = 1.0031–1.0711, p = 0.0319). No evidence of heterogeneity between genetic variants was found (e.g., IBD vs. celiac disease, MR-Egger Q = 47.4391, p = 0.6159). Horizontal pleiotropy hardly influenced causality (e.g., IBD vs. celiac disease, MR-Egger test: p = 0.4340). Leave-one-out analysis showed that individual SNPs did not influence the general results.

Conclusion: Our MR analysis revealed a positive causal link between IBD and celiac disease in the European population. In addition, several recommendations for disease prevention and clinical management have been discussed.

Association of Celiac Disease and Inflammatory Bowel Disease: A Nationwide Register-Based Cohort Study

INTRODUCTION

To determine the risk of inflammatory bowel disease (IBD) in patients with celiac disease (CeD) (and vice versa ) compared with general-population comparators.

METHODS

Using Swedish histopathology and healthcare register data, we identified 48,551 patients with CeD and 83,529 with IBD diagnosed in 1969-2016. Each patient was compared with age- and sex-matched general-population comparators (CeD: n = 240,136; IBD: n = 408,195). Cox regression estimated hazard ratios (HRs) for IBD in patients with CeD and vice versa . Our main analyses were limited to events beyond the first year of follow-up to reduce potential surveillance bias.

RESULTS

During follow-up, 784 (1.6%) patients with CeD were diagnosed with IBD compared with 1,015 (0.4%) matched comparators. In patients with CeD, the HR for IBD was 3.91 (95% confidence interval [CI] 3.56-4.31), with largely similar HRs for Crohn's disease (4.36; 3.72-5.11) and ulcerative colitis (3.40; 3.00-3.85). During follow-up, 644 (0.8%) patients with IBD and 597 (0.1%) comparators were diagnosed with CeD. The HR for CeD in patients with IBD was 5.49 (95% CI 4.90-6.16), with the highest risk estimates seen in ulcerative colitis (HR = 6.99; 6.07-8.05), and the HR for Crohn's disease was 3.31 (2.69-4.06). In patients with CeD and IBD, the diagnostic interval was usually &lt;1 year; however, HRs of 3-4 were seen even after 10 years of follow-up. During 20 years of follow-up, 2.5% of patients with CeD developed incident IBD, and 1.3% of patients with IBD developed CeD.

DISCUSSION

The bidirectional association between CeD diagnosis and IBD warrants attention in the initial assessment and follow-up of these conditions. Their co-occurrence, independent of temporal sequence, suggests shared etiology.

Inflammatory bowel disease and celiac disease: A bidirectional Mendelian randomization study

Objective: Although previous epidemiological studies have reported substantial links between inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), and celiac disease (CeD), the causal relationship between the two remains unknown. The purpose of the current study was to evaluate the bidirectional causation between IBD and CeD using Mendelian randomization (MR).

Method: We obtained genome-wide association study (GWAS) summary data of IBD (CD and UC) and CeD of thoroughly European ancestry from the IEU GWAS database. We screened eligible instrumental variables (IVs) according to the three assumptions of MR. MR was performed using MR-Egger, weighted median (WM), and inverse variance weighted (IVW) methods. The MR-Egger intercept and MR-PRESSO method investigated the horizontal pleiotropy effect. A leave-one-out analysis was performed to prevent bias caused by a single SNP.

Results: The study assessed a bidirectional causal effect between CD and CeD; CD increased the risk of CeD (IVW odds ratio (OR) = 1.27, 95% confidence interval (CI) = 1.19–1.35, p = 3.75E-13) and vice-a-versa (IVW OR = 1.09, 95% CI = 1.05–1.13, p = 1.39E-05). Additionally, CeD was influenced by IBD (IVW OR = 1.24, 95% CI = 1.16–1.34, p = 9.42E-10) and UC (IVW OR = 0.90, 95% CI = 0.83–0.98, p = 0.017). However, we observed no evidence of a causal relationship between CeD and IBD (IVW OR = 1.00, 95% CI = 0.97–1.04, p = 0.900) or UC (IVW OR = 0.96, 95% CI = 0.92–1.02, p = 0.172).

Conclusion: The present study revealed that IBD and CeD have a bidirectional causal relationship. However, it is slightly different from the results of previous observational studies, recommending that future studies focus on the mechanisms of interaction between CD and CeD.

Characteristics of inflammatory bowel diseases in patients with concurrent immune-mediated inflammatory diseases

Patients with inflammatory bowel disease (IBD) are more likely to have concurrent immune-mediated inflammatory diseases (IMIDs) than those without IBD. IMIDs have been observed to alter the phenotype and outcomes of IBD in recent studies. Several studies have found that IBD patients with concurrent IMIDs may have more extensive or severe disease phenotypes, and are considered to be at increased risk of requiring biologics and IBD-related surgeries, suggesting that having multiple IMIDs is a poor prognostic factor for IBD. Furthermore, IBD patients with primary sclerosing cholangitis and Takayasu arteritis are reported to have unique endoscopic phenotypes, suggesting concurrent IMIDs can influence IBD phenotype with specific intestinal inflammatory distributions. In this review, we discuss the pathogenesis, disease phenotypes, and clinical outcomes in IBD patients with concomitant IMIDs.

Pancreatic involvement in celiac disease

Celiac disease (CD) is well recognized as a systemic, chronic autoimmune disease mainly characterized by gluten-sensitive enteropathy in genetically predisposed individuals but with various extraintestinal features. One of the affected organs in CD is the pancreas, consisting of both endocrine and exocrine alterations. Over the last decades there has been increasing interest in the pancreatic changes in CD, and this has been reflected by a great number of publications looking at this extraintestinal involvement during the course of CD. While pancreatic endocrine changes in CD, focusing on type 1 diabetes mellitus, are well documented in the literature, the relationship with the exocrine pancreas has been less studied. This review summarizes currently available evidence with regard to pancreatic exocrine alterations in CD, focusing on risk of pancreatitis in CD patients, association with autoimmune pancreatitis, prevalence and outcomes of pancreatic exocrine insufficiency in newly diagnosed and gluten-free diet treated CD patients, and the link with cystic fibrosis. In addition, we discuss mechanisms behind the associated pancreatic exocrine impairment in CD and highlight the recommendations for clinical practice.

Coeliac disease

Coeliac disease is an autoimmune disorder that primarily affects the small intestine, and is caused by the ingestion of gluten in genetically susceptible individuals. Prevalence in the general population ranges from 0·5% to 2%, with an average of about 1%. The development of the coeliac enteropathy depends on a complex immune response to gluten proteins, including both adaptive and innate mechanisms. Clinical presentation of coeliac disease is highly variable and includes classical and non-classical gastrointestinal symptoms, extraintestinal manifestations, and subclinical cases. The disease is associated with a risk of complications, such as osteoporosis and intestinal lymphoma. Diagnosis of coeliac disease requires a positive serology (IgA anti-transglutaminase 2 and anti-endomysial antibodies) and villous atrophy on small-intestinal biopsy. Treatment involves a gluten-free diet; however, owing to the high psychosocial burden of such a diet, research into alternative pharmacological treatments is currently very active.

Patients With Inflammatory Bowel Disease on Treatment Have Lower Rates of Celiac Disease

BACKGROUND

The association between celiac disease and inflammatory bowel disease (IBD) has been studied; however, the impact of IBD therapy on celiac disease is not known. Using a large database, we sought to describe the association of celiac disease and IBD and the impact of IBD treatment.

METHODS

We queried a large multicenter database (Explorys Inc.), an electronic health record data aggregate from 26 American health care systems. We identified a cohort of patients with celiac disease and IBD between 1999 and 2020 and conducted a statistical analysis using a multivariate model.

RESULTS

Of the 72,965,940 individuals in the database, 133,400 had celiac disease (0.18%), 191,570 (0.26%) had ulcerative colitis (UC), and 230,670 (0.32%) had Crohn disease (CD). Patients with IBD were more likely to have a diagnosis of celiac disease (odds ratio [OR], 13.680), with a greater association with CD. Treated patients with UC and with CD, respectively, had a lower risk association with celiac disease compared to those not undergoing IBD treatment, specifically corticosteroids (OR, 0.407 and 0.585), 5-aminosalicylates (OR, 0.124 and 0.127), immunomodulators (OR, 0.385 and 0.425), and anti-tumor necrosis factor drugs (OR, 0.215 and 0.242). There was no lower risk association in the vedolizumab group, but there was a higher risk association among the ustekinumab group.

CONCLUSIONS

In this large dataset, we showed a bidirectional association between celiac disease and IBD that was stronger with CD. Patients with IBD treated using corticosteroids, 5-aminosalicylates, immunomodulators, or anti-tumor necrosis factor drugs had a lower association with celiac disease. Additional studies are required to determine the underlying mechanisms for IBD therapy-related modification of celiac disease incidence.

Immune‐mediated inflammatory diseases of the gastrointestinal tract: Beyond Crohn's disease and ulcerative colitis

Immune‐mediated inflammatory diseases (IMIDs) are a diverse group of complex inflammatory diseases that result from dysregulated immune pathways and can involve any system of the human body. Inflammatory bowel disease (IBD) is one such disease involving the gastrointestinal (GI) system. With high prevalence in the West and increasing incidence in newly industrialized countries, IBD poses a significant burden on health care. IMIDs of the GI system other than IBD can have similar clinical features, causing diagnostic and therapeutic challenges. Although these disorders share a common pathophysiology, the defects can occur anywhere in the complex network of cytokines, inflammatory mediators, and innate and adaptive systems, leading to unregulated inflammation. Precise knowledge about them will help determine the possible targeted therapy. Thus, it is essential to distinguish these disorders from IBD. This review describes various IMIDs of the GI tract that mimic IBD.

Pediatric Inflammatory Bowel Disease Associated With Celiac Disease: A Retrospective Study in a Tertiary Care Hospital in Saudi Arabia

Background. Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn’s disease (CD), is a chronic relapsing disease indicated by inflammation of the gastrointestinal tract. Celiac disease (CeD) is a chronic autoimmune disease of the small bowel. The prevalence of CeD in IBD patients is unknown. Some studies have described the coexistence of the 2 diseases in the same patient. This study aimed to investigate the prevalence of CeD in Saudi Arabian children with IBD. Methods. We used a retrospective study design because data can be collected immediately and is easier to analyze afterward. The study was conducted on IBD patients in the Pediatric Gastroenterology Department at National Guard Hospital, Jeddah, Saudi Arabia. We enrolled Saudi patients aged between 1 and 18 years who had been diagnosed with IBD and CeD based on positive biochemical serology and histology from January 2011 to January 2020. We excluded patients with immunodeficiency disorders. Results. Among the 46 enrolled patients with IBD, CeD was identified in 4, and they did not develop any relapses. We discovered that the weight at IBD diagnosis improved significantly compared to current weight (P-value < .0001). We also discovered that the height at diagnosis of IBD improved significantly compared to the current height (P-value < .0001). Additionally, we found no significant associations between UC and CeD (P-value = 1), or CD and CeD (P-value = .625). Conclusion. No significant associations were evident between the prevalence of CeD and IBD. More prospective multicenter studies are needed to clarify the prevalence of CeD in children with IBD.

Regional Variation in Pregnancy Outcomes amongst Women in Inflammatory Bowel Disease: A Population-Based Cohort Study

BACKGROUND

Women with inflammatory bowel disease (IBD) are at risk of certain pregnancy outcomes such as preterm delivery, infants small for gestational age (SGA), and Cesarean delivery. Whether regional variation in these outcomes exists remains unknown. We aimed to assess the geographical variation in these pregnancy outcomes in women with IBD.

METHODS

All pregnancies in women with and without IBD (2002-2013) were identified using Ontario health administrative datasets. Geographical variation in preterm delivery, infants SGA, and Cesarean delivery was assessed using age-adjusted odds ratios (aOR) with 95% confidence intervals (CI) comparing women with and without IBD, stratified by Ontario's 14 health-service regions, known as Local Health Integration Networks (LHINs).

RESULTS

1621 women with IBD (2466 pregnancies) and 855,425 women without IBD (1,280,493 pregnancies) were included. Women with IBD were more likely to have preterm delivery (aOR 1.56, 95% CI, 1.35-1.79), infants SGA (aOR 1.52, 95% CI, 1.23-1.88), and Cesarean section (aOR 1.34, 95% CI, 1.22-1.49). Significant geographical variation in these outcomes was detected, with the highest rates observed in the most northern rural areas (aOR for preterm delivery 2.78 (95% CI, 1.03-7.46), aOR for SGA 5.66 (95% CI, 1.67-19.14), and aOR for Cesarean delivery 2.48 (95% CI, 1.11-5.55)). There were no differences in these outcomes in women with and without IBD in more central urban LHINs.

CONCLUSION

Significant regional variation was detected in rates of adverse pregnancy outcomes and Cesarean delivery in women with IBD. Further study is required to determine specific reasons for this variation.

Guidelines for the management of patients with Crohn's disease. Recommendations of the Polish Society of Gastroenterology and the Polish National Consultant in Gastroenterology

This paper is an update of the diagnostic and therapeutic recommendations of the National Consultant for Gastroenterology and the Polish Society of Gastroenterology from 2012. It contains 46 recommendations for the diagnosis and treatment, both pharmacological and surgical, of Crohn's disease in adults. The guidelines were developed by a group of experts appointed by the Polish Society of Gastroenterology and the National Consultant in the field of Gastroenterology. The methodology related to the GRADE methodology was used to assess the quality and strength of the available recommendations. The degree of expert support for the proposed statement, assessment of the quality of evidence and the strength of the recommendation was assessed on a 6-point Likert scale. Voting results, quality and strength ratings with comments are included with each statement.

Phenotype and Natural History of Children With Coexistent Inflammatory Bowel Disease and Celiac Disease

BACKGROUND

Adult patients with both inflammatory bowel disease (IBD) and celiac disease (CeD) have peculiar phenotypic features. This study aimed at describing the characteristics and natural history of children with both IBD and CeD.

METHODS

This was a case-control study based on a national registry. Cases included children diagnosed with both IBD and CeD. Two matched IBD controls without CeD, and 2 matched CeD controls were selected for each case. Inflammatory bowel disease phenotype and natural history, comprising growth and pubertal development, were compared between groups.

RESULTS

Forty-nine (1.75%) patients with IBD and CeD were identified out of 2800 patients with IBD. Compared with patients with IBD alone, patients with IBD and CeD presented more frequently with autoimmune diseases (odds ratio, 2.81; 95% CI, 0.97-8.37; P = 0.04). Ileocolonic localization (46.1% vs 73.1%), treatment with azathioprine (46.2% vs 71.2%), and anti-TNF biologics (46.2% vs 69.2%) were less common in patients with Crohn's disease and CeD than in patients with Crohn's disease alone. Patients with ulcerative colitis and CeD had an increased risk of colectomy despite similar medical treatments compared with patients with ulcerative colitis alone (13.0% vs 0%). Pubertal delay was more common in patients with IBD and CeD compared with patients with IBD alone (14.9% vs 3.2%; odds artio, 5.24; 95% CI, 1.13-33.0; P = 0.02) and CeD alone (14.9% vs 1.1%; P = 0.002).

CONCLUSIONS

Children with IBD and CeD may have peculiar features with a higher risk for autoimmune diseases, colectomy, and pubertal delay compared with IBD alone.

Manipulation of the gut microbiome in gluten-intolerance

PURPOSE OF REVIEW

Gluten is a complex mixture of highly immunogenic glutamine- and proline-rich proteins found in some cereals. In celiac disease (CeD), gluten triggers an autoimmune response due to its interaction with the human leukocyte antigen heterodimers that confer the genetic risk. The involvement of gluten in other disorders has also been investigated, but its role beyond CeD is still unclear. Here, we review the most recent evidence of the involvement of gluten in diseases and the opportunities of manipulating the gut microbiota to treat or prevent gluten-related conditions.

RECENT FINDINGS

Most of the new studies have been conducted in the context of CeD, where important evidence has been gained on associations between the gut microbiota, genotype, and environmental factors such as breastfeeding and antibiotics. The role of the microbiota has been investigated in several prospective, observational and interventional studies with probiotics, which together showed that the gut microbiota could be targeted to ameliorate and aid in the prevention of CeD development.

SUMMARY

Several studies have evidenced how genetic and environmental factors influence the gut microbiome with consequences in CeD. These findings could inspire the development of microbiota modulation strategies to support the prevention or treatment of CeD.

Celiac disease: clinical update

PURPOSE OF REVIEW

This review highlights literature from the past year and explores the impact on current understanding of celiac disease pathogenesis, diagnosis, and management.

RECENT FINDINGS

In contrast to earlier clinical trials, recent data suggests that early gluten introduction may protect against the development of celiac disease. Celiac disease is underdiagnosed, associated with high burden of disease and linked to excess mortality risk, yet, there remains considerable uncertainty regarding the utility of mass screening in asymptomatic individuals. The gut microbiome is increasingly implicated in celiac disease pathogenesis, although the exact mechanism is undefined. Probiotics have been proposed as a disease-modifying option for celiac disease but most studies assessing efficacy are of low-quality. Patients with celiac disease do not appear to be at increased risk of contracting or developing adverse outcomes from COVID-19. Little is known about the pathogenesis of nonceliac gluten sensitivity; however, recent findings suggest an autoimmune basis for the condition.

SUMMARY

Current understanding of celiac disease continues to advance, though significant knowledge gaps remain. Large, rigorous, prospectively designed studies are needed to further characterize celiac disease pathogenesis, management and therapeutic options.

The accuracy of diagnostic indicators for coeliac disease: A systematic review and meta-analysis

BACKGROUND

The prevalence of coeliac disease (CD) is around 1%, but diagnosis is challenged by varied presentation and non-specific symptoms and signs. This study aimed to identify diagnostic indicators that may help identify patients at a higher risk of CD in whom further testing is warranted.

METHODS

International guidance for systematic review methods were followed and the review was registered at PROSPERO (CRD42020170766). Six databases were searched until April 2021. Studies investigating diagnostic indicators, such as symptoms or risk conditions, in people with and without CD were eligible for inclusion. Risk of bias was assessed using the QUADAS-2 tool. Summary sensitivity, specificity, and positive predictive values were estimated for each diagnostic indicator by fitting bivariate random effects meta-analyses.

FINDINGS

191 studies reporting on 26 diagnostic indicators were included in the meta-analyses. We found large variation in diagnostic accuracy estimates between studies and most studies were at high risk of bias. We found strong evidence that people with dermatitis herpetiformis, migraine, family history of CD, HLA DQ2/8 risk genotype, anaemia, type 1 diabetes, osteoporosis, or chronic liver disease are more likely than the general population to have CD. Symptoms, psoriasis, epilepsy, inflammatory bowel disease, systemic lupus erythematosus, fractures, type 2 diabetes, and multiple sclerosis showed poor diagnostic ability. A sensitivity analysis revealed a 3-fold higher risk of CD in first-degree relatives of CD patients.

CONCLUSIONS

Targeted testing of individuals with dermatitis herpetiformis, migraine, family history of CD, HLA DQ2/8 risk genotype, anaemia, type 1 diabetes, osteoporosis, or chronic liver disease could improve case-finding for CD, therefore expediting appropriate treatment and reducing adverse consequences. Migraine and chronic liver disease are not yet included as a risk factor in all CD guidelines, but it may be appropriate for these to be added. Future research should establish the diagnostic value of combining indicators.

Iron Deficiency in Celiac Disease: Prevalence, Health Impact, and Clinical Management

Iron is an essential nutrient to life and is required for erythropoiesis, oxidative, metabolism, and enzymatic activities. It is a cofactor for mitochondrial respiratory chain enzymes, the citric acid cycle, and DNA synthesis, and it promotes the growth of immune system cells. Thus, iron deficiency (ID) leads to deleterious effects on the overall health of individuals, causing significant morbidity. Iron deficiency anemia (IDA) is the most recognized type of anemia in patients with celiac disease (CD) and may be present in over half of patients at the time of diagnosis. Folate and vitamin B12 malabsorption, nutritional deficiencies, inflammation, blood loss, development of refractory CD, and concomitant Heliobacter pylori infection are other causes of anemia in such patients. The decision to replenish iron stores and the route of administration (oral or intravenous) are controversial due, in part, to questions surrounding the optimal formulation and route of administration. This paper provides an algorithm based on the severity of symptoms; its impact on the health-related quality of life (HRQL); the tolerance and efficiency of oral iron; and other factors that predict a poor response to oral iron, such as the severity of histological damage, poor adherence to GFD, and blood loss due to mucosal lesions.

Celiac disease in the COVID-19 pandemic

Background

The COVID-19 pandemic has had an impact on global health.

Design

The impact of the COVID-19 pandemic on patients with coeliac disease was assessed in the present review.

Results

The incidence of coeliac disease and the problems associated with coeliac disease increased during the COVID-19 pandemic. Adherence to the diet is crucial for the patient's health and quality of life since the only approved therapy for coeliac disease is a gluten withdrawal.

Conclusions

A gluten-free diet should be promoted by the therapeutic team and implemented among these categories of patients.

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Health education to follow the GFD does not exist in many countries. Unfortunately, the COVID-19 pandemic has increased psychological problems among patients with CD.

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The association of T1D with CD has been and remains a problem in CD management.

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Associating IBD with CD is again a challenge. Psychological problems also appeared in the associations of CD with T1D and IBD. The COVID-19 virus did not pose an increased risk to CD patients, but the COVID-19 pandemic brought many psychological problems to CD patients.

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CD patients should adhere to GFD, in general, hence pay attention to gluten withdrawal during the COVID-19 pandemics, to avoid other complications and improve their QOL.

Inflammatory Bowel Disease: Are Symptoms and Diet Linked?

New Zealand (NZ) has one of the world’s highest incidence rates of Inflammatory Bowel Disease (IBD), a group of chronic inflammatory conditions that affect the gastrointestinal tract. Patients with IBD often believe certain foods influence their disease symptoms and consequently may alter their diet considerably. The objective of this study was to determine foods, additives, and cooking methods (dietary elements) that NZ IBD patients identify in the onset, exacerbation, or reduction of their symptoms. A total of 233 participants completed a self-administered questionnaire concerning symptom behaviour in association with 142 dietary elements. Symptom onset and symptom exacerbation were associated with dietary elements by 55% (128) and 70% (164) of all IBD participants, respectively. Fruit and vegetables were most frequently identified, with dairy products, gluten-containing bread, and foods with a high fat content also considered deleterious. Of all IBD participants, 35% (82) associated symptom reduction with dietary elements. The identified foods were typically low in fibre, saturated fatty acids, and easily digestible. No statistically significant differences were seen between the type or number of dietary elements and disease subtype or recent disease activity. The association between diet and symptoms in patients with IBD and the mechanism(s) involved warrant further research and may lead to the development of IBD specific dietary guidelines.

Prevalence of Celiac Disease in Children and Adolescents With Inflammatory Bowel Disease

Introduction

The association between inflammatory bowel disease (IBD) - particularly its two main subtypes, ulcerative colitis (UC) and Crohn’s disease (CD) - and celiac disease (CeD) has been attributed to an overlap in the mechanism of immune dysregulation that characterizes these conditions. Owing to the paucity of studies that have explored this condition in pediatric patients, we examined the prevalence of CeD in children with IBD.

Materials and methods

This is a cross-sectional study of children aged two to 18 years with IBD that were diagnosed between 2016 and 2018. Clinical, demographic, laboratory, and endoscopic data were analysed. Serology for CeD measured the immunoglobulin A tissue transglutaminase (IgA-tTG) antibodies, and the diagnosis was confirmed histologically through small bowel biopsies.

Results

The study included 101 patients with IBD (83.2% with UC and 16.8% with CD). The mean age was 8.7±4.0 years. Males constituted 59.4% of the cohort, and only 3% had perianal disease. Ileocolonic involvement was reported in 64.7% and non-stricturing and non-penetrating behaviour in 76.7% of CD patients. Pancolitis constituted 45.2% of UC patients. Ten patients (9.9%) had positive serology based on IgA-tTG antibodies, three (approximately 3%) had CeD based on biopsy findings, two patients (2%) had CD, and one patient (1%) had UC. Patients with confirmed CeD had a significantly higher frequency of symptoms of gaseous sensation and bloating (P=0.003) and abdominal distension (P=0.04).

Conclusions

The prevalence of CeD in Egyptian children with IBD is higher than previously reported in a number of similar studies. Abdominal bloating and gaseous sensation were identified as associated symptoms.