Nutritional Considerations in Celiac Disease and Non-Celiac Gluten/Wheat Sensitivity

A gluten-free diet (GFD) is the only available treatment for celiac disease (CeD), and it may also improve symptoms in non-celiac gluten/wheat sensitivity (NCGWS). In CeD, gluten triggers an immune reaction leading to enteropathy, malabsorption, and symptoms; in NCGWS, the mechanism leading to symptoms is unknown, and neither wheat nor gluten triggers enteropathy or malabsorption. A strict GFD is, therefore, necessary for CeD, but a gluten-restricted diet (GRD) may suffice to achieve symptom control for NCGWS. Regardless of this distinction, the risk of malnutrition and macro- and micronutrient deficiencies is increased by the adoption of a GFD or GRD. Thus, patients with CeD or NCGWS should undergo nutritional assessment and subsequent monitoring, based on evidence-based tools, under the care of a multidisciplinary team involving physicians and dietitians, for the long-term management of their nutrition. This review gives an overview of available nutrition assessment tools and considerations for the nutritional management of CeD and NCGWS populations.

Clinical Presentation Is Dependent on Age and Calendar Year of Diagnosis in Celiac Disease: A Hungarian Cross-Sectional Study

International trends indicate that celiac disease (CeD) is becoming more common, while the clinical presentation of CeD tends to change. We aimed to investigate factors associated with the clinical presentation of CeD. We reviewed all CeD cases diagnosed at our tertiary center, University of Pécs (Hungary), between 1992 and 2019. We collected data of verified CeD patients on clinical presentations (classified by the Oslo Classification), the age at and calendar year of diagnosis, and sex, serology and histology at diagnosis. To assess the associations of baseline variables with clinical presentations, we applied univariate and multivariate (binary logistic regression) statistics. A total of 738 CeD patients were eligible for inclusion. In the univariate analysis, patients with classical CeD were more common in the latest calendar period (p < 0.001) and tended to be older (p = 0.056), but we failed to observe a significant association between the clinical presentation and sex, serology or histology at diagnosis. In the multivariate analysis, only age at diagnosis and calendar year were independently associated with clinical presentations (OR = 1.02, CI: 1.01-1.04 and OR = 0.93, CI: 0.89-0.98, respectively). Our findings confirmed that classical CeD is independently associated with age at diagnosis and calendar year of diagnosis of CeD, whereas other parameters were not significantly associated with clinical presentations.

Evaluation of a Single Determination of Gluten Immunogenic Peptides in Urine from Unaware Celiac Patients to Monitor Gluten-Free Diet Adherence

INTRODUCTION AND AIM

Usually, adherence to the gluten-free diet (GFD) in celiac patients is indirectly assessed through serological analysis, questionnaires, or invasive methods such as intestinal biopsy. The detection of gluten immunogenic peptides in urine (urinary gluten immunogenic peptides-uGIP) is a novel technique that directly evaluates the ingestion of gluten. The aim of this study was to evaluate the clinical efficacy of uGIP in the follow-up of celiac disease (CD).

METHODS

From April 2019 to February 2020, CD patients reporting complete adherence to the GFD were prospectively enrolled but were unaware of the reason for the tests. Urinary GIP, the celiac dietary adherence test (CDAT), symptomatic visual analog scales (VAS), and tissue transglutaminase antibodies (tTGA) titres were evaluated. Duodenal histology and capsule endoscopy (CE) were performed when indicated.

RESULTS

A total of 280 patients were enrolled. Thirty-two (11.4%) had a positive uGIP test (uGIP+). uGIP+ patients did not show significant differences in demographic parameters, CDAT, or VAS scores. The tTGA+ titre was not related to the positivity of uGIP (14.4% vs. 10.9% in patients with tTGA+ and tTGA-). Regarding histology, 66.7% of the GIP+ patients had atrophy compared to 32.7% of the GIP patients (p-value 0.01). However, the presence of atrophy did not correlate with tTGA. Mucosal atrophy was detected in 29 (47.5%) out of 61 patients by CE. With this method, no noticeable dependence on uGIP results (24 GIP- vs. 5 GIP+) was observed.

CONCLUSIONS

The single uGIP test was positive in 11% of CD cases referring a correct GFD adherence. Furthermore, uGIP results significantly correlated with the duodenal biopsy, formerly considered the gold standard for assessing CD activity.

Regional Swedish study found that one in seven coeliac patients experienced loss of follow up during childhood

AIM

To examine the clinical follow up of paediatric coeliac disease and the rate of loss of follow up during childhood, for which data are scarce.

METHODS

In a cohort of coeliac children diagnosed in 2013-2018 in Gothenburg, Sweden, we retrospectively explored the follow-up practice of paediatric coeliac disease until June 2021. We used medical records from hospital-based paediatric gastroenterology and general paediatric outpatient clinics, laboratory records, and questionnaires. Loss of follow up was defined no coeliac disease-related follow up or tissue transglutaminase test over the past 2 years of study enrolment.

RESULTS

We included 162 children (58% girls) aged 7.8-18.2 years (average 12.7). Most participants (76%) were followed at general paediatric outpatient clinics rather than hospital-based clinics. After 2.3-8.8 (average 5.3) years since diagnosis, 23 patients (14%; 95% confidence interval, 9%-21%) had been lost to follow up. Patients with loss of follow up were more often boys (61% versus 39%, p = 0.08), with a somewhat longer average disease duration of 5.8 versus 5.2 years (p = 0.11). There were no between-group differences in socio-economic characteristics and patient-reported experience measures of coeliac disease care.

CONCLUSION

One in seven coeliac patients may experience loss of follow up during childhood.

Sleep disorders in children with celiac disease: a prospective study

STUDY OBJECTIVES

Celiac disease (CD), an immune-mediated enteropathy, has a clinical spectrum that is remarkably wide and includes neuropsychiatric manifestations. While studies of adults have shown sleep disturbances, there is limited data in children. Our objectives were to assess the association between sleep disturbances and CD in children, and the effect of a gluten-free diet.

METHODS

Parents of children 3-12 years old referred for endoscopy completed the Sleep Disturbance Scale for Children and modified Epworth Sleepiness Scale. Children with CD were compared with healthy controls and children with abdominal pain but no definitive findings on investigation. Parents of children with CD and abdominal pain were contacted after 6 months for follow-up.

RESULTS

We enrolled 101 patients, mean age 6.5 (2.8), 51% female, 38 with CD, 18 abdominal pain, and 45 healthy. Sleep Disturbance Scale for Children scores were 37.4 (8.7), 41.3 (11.3), and 45.4 (13.7) in healthy controls, CD, and abdominal pain, respectively (P = .024). There was a significant difference in the disorders of arousal domain (P = .044). There were no significant differences on the modified Epworth Sleepiness Scale. A trend toward improvement in Sleep Disturbance Scale for Children scores was seen in children with CD presenting with abdominal pain after 6 months on a gluten-free diet (P = .07).

CONCLUSIONS

In this first prospective study of sleep disturbances in children with CD, we show high rates of disturbed sleep compared with healthy children. Sleep disturbances did not improve on a gluten-free diet and may be driven by abdominal pain.

CITATION

Reiter J, Abuelhija H, Slae M, et al. Sleep disorders in children with celiac disease: a prospective study. J Clin Sleep Med. 2023;19(3):591-594.

Duodenal inflammation in common variable immunodeficiency has altered transcriptional response to viruses

BACKGROUND

A substantial proportion of common variable immunodeficiency (CVID) patients has duodenal inflammation of largely unknown etiology. However, because of its histologic similarities with celiac disease, gluten sensitivity has been proposed as a potential mechanism.

OBJECTIVE

We aimed to elucidate the role of the duodenal microenvironment in the pathogenesis of duodenal inflammation in CVID by investigating the transcriptional, proteomic, and microbial signatures of duodenal biopsy samples in CVID.

METHODS

DNA, total RNA, and protein were isolated from snap-frozen pieces of duodenal biopsy samples from CVID (with and without duodenal inflammation), healthy controls, and patients with celiac disease (untreated). RNA sequencing, mass spectrometry-based proteomics, and 16S ribosomal DNA sequencing (bacteria) were then performed.

RESULTS

CVID separated from controls in regulation of transcriptional response to lipopolysaccharide and cellular immune responses. These differences were independent of mucosal inflammation. Instead, CVID patients with duodenal inflammation displayed alterations in transcription of genes involved in response to viral infections. Four proteins were differently regulated between CVID patients and healthy controls-DBNL, TRMT11, GCHFR, and IGHA2-independent of duodenal inflammation. Despite similar histology, there were major differences in CVID with duodenal inflammation and celiac disease both at the RNA and protein level. No significant difference was observed in the bacterial gut microbial signature between CVID, celiac, and healthy controls.

CONCLUSION

Our findings suggest the existence of altered functions of the duodenal epithelium, particularly in response to lipopolysaccharide and viruses. The latter finding was related to duodenal inflammation, suggesting that viruses, not gluten sensitivity, could be related to duodenal inflammation in CVID.

Early Antibody Dynamics in a Prospective Cohort of Children At Risk of Celiac Disease

INTRODUCTION

The purpose of this study was to identify possible serum biomarkers predicting celiac disease (CD) onset in children at risk.

METHODS

A subgroup from an ongoing, international prospective study of children at risk of CD was classified according to an early trajectory of deamidated gliadin peptides (DGPs) immunoglobulin (Ig) G and clinical outcomes (CD, potential CD, and CD autoimmunity).

RESULTS

Thirty-eight of 325 children developed anti-tissue transglutaminase IgA antibody (anti-tTG IgA) seroconversion. Twenty-eight of 38 children (73.6%) showed an increase in anti-DGPs IgG before their first anti-tTG IgA seroconversion.

DISCUSSION

Anti-DGPs IgG can represent an early preclinical biomarker predicting CD onset in children at risk.

Celiac disease and risk of microscopic colitis: A nationwide population-based matched cohort study

BACKGROUND

An association has been reported between celiac disease (CD) and microscopic colitis (MC). However, large, population-based cohort studies are rare.

OBJECTIVE

To systematically examine the association between CD and MC in a large, nationwide cohort.

METHODS

We conducted a nationwide population-based matched cohort study in Sweden of 45,138 patients with biopsy-verified CD (diagnosed in 1990-2016), 223,149 reference individuals, and 51,449 siblings of CD patients. Data on CD and MC were obtained from all (n = 28) pathology departments in Sweden. Adjusted hazard ratios (aHRs) were calculated using Cox regression.

RESULTS

During follow-up, 452 CD patients and 197 reference individuals received an MC diagnosis (86.1 vs. 7.5 per 100,000 person-years). This difference corresponded to an aHR of 11.6 (95% confidence interval [CI] = 9.8-13.8) or eight extra MC cases in 1000 CD patients followed up for 10 years. Although the risk of MC was highest during the first year of follow-up (aHR 35.2; 95% CI = 20.1-61.6), it remained elevated even after 10 years (aHR 8.1; 95% CI = 6.0-10.9). Examining MC subtypes lymphocytic colitis (LC) and collagenous colitis (CC) separately, the aHR was 12.4 (95% CI = 10.0-15.3) for LC and 10.2 (95% CI = 7.7-13.6) for CC. MC was also more common before CD (adjusted odds ratio [aOR] = 52.7; 95% CI = 31.4-88.4). Compared to siblings, risk estimates decreased but remained elevated (CD and later MC: HR = 6.2; CD and earlier MC: aOR = 7.9).

CONCLUSION

Our study demonstrated a very strong association of MC with CD with an increased risk of future and previous MC in CD patients. The magnitude of the associations underscores the need to consider the concomitance of these diagnoses in cases in which gastrointestinal symptoms persist or recur despite a gluten-free diet or conventional MC treatment. The comparatively lower risk estimates in sibling comparisons suggest that shared genetic and early environmental factors may contribute to the association between CD and MC.

Psychiatric and Neurological Manifestations of Celiac Disease in Adults

Celiac disease (CD), a chronic inflammatory disorder of the intestines, affects 0.7% to 1.4% of the world's population. CD causes diarrhea, abdominal discomfort, bloating, flatulence, and, in rare cases, constipation in the digestive tract. Since the identification of gluten as the disease-causing antigen, CD patients have been treated with a gluten-free diet, which is advantageous but has limitations for certain patient groups. CD is associated with mood disorders, such as manic-depressive disease, schizophrenia, and bipolar disorder, as well as other disorders such as depression and anxiety. The relationship between CD and psychological issues is not entirely understood. Here, we look at the most recent psychiatric data as they pertain to CD, as well as the relevant psychiatric manifestations that have been associated with this condition. Clinicians should examine mental health factors when a CD diagnosis is established. More research is needed to understand the pathophysiology of CD's psychiatric manifestations.

Musculoskeletal Complications of Celiac Disease: A Case-Based Review

Primary diagnosis of celiac disease (CD) in rheumatology department is not common in daily clinical practice, due to the fact that diarrhoea is usually the dominant symptom. Extra-intestinal manifestations, such as arthralgia, myalgia, osteomalacia, and osteoporosis are not rare in these patients. We present a case of a 66-year-old man, who came to the outpatient rheumatology clinic, complaining of back and knee pain. Osteopenia was observed in plain radiographs, whereas extensive laboratory testing revealed celiac disease, vitamin D deficiency, and extremely low bone mineral density (BMD) due to osteomalacia. Gluten-free diet (GFD) initiation and administration of vitamin D and calcium supplements resulted in significant symptom and BMD improvement over 6 months. A significant proportion of CD patients might present with arthralgia, arthritis, back pain, myalgia, or bone pain. Importantly, up to 75% of patients might have reduced BMD, due to osteoporosis or osteomalacia, while they also carry a significant risk for fracture. However, the introduction of GFD and calcium/vitamin D supplementation significantly ameliorates symptoms and BMD in most cases. Increased awareness of CD's musculoskeletal manifestations by rheumatologists is important for early recognition and management of this condition and its complications.

Discussing health while seeking community: A descriptive study of celiac disease on TikTok

Background: For individuals suffering from chronic disease, more than being an information source for health information, social media serves as a dynamic forum for shared goals, emotional and practical support through the sharing of lived experiences. Aim: This study envisaged a content analysis of the 100 most widely-viewed English language videos related to celiac disease posted on TikTok. Methods: TikTok was searched using the hashtag #celiacdisease. This search term was chosen as it represented the broadest summation of the desired topic with the most views (80 million) of any related hashtag. The first 100 English language videos were selected. The video content was analyzed against predetermined descriptive categories, deductively derived content related to facts about celiac disease from a reliable source, and inductive content categories derived during the coding process. Results: The 100 videos included in this study received a total of 44,056,600 likes. The average number of likes across all videos was 440,566 with a standard deviation of 656,642.06. Two of the three categories were present in a majority (>50) of the videos. They were practical information on diet therapy management (n = 63) and challenges in managing celiac disease (n = 73). In both instances, videos featuring this content also garnered a majority of the likes, 74.18% and 82.9% respectively. Independent one-tailed t-tests (α = .05) returned significant results for the diagnosis-related information (p = .0390) and practical information in diet therapy management (p = .0358) categories. On average, videos that included diagnosis-related information received more likes than those that did not: 672,983.33 vs. 340,958.57. Similarly, the average number of likes was significantly higher for videos that included practical information on diet therapy management (518,715.87) vs. those that did not (307,500). Conclusions: This study further confirms the growing trend of people using social media to discuss health issues in a way that is free and easily accessible among communities with shared experiences. The long-term effects of using personal narratives as credible sources of behavioral change for health, medical, or professional resources can be further investigated.

Inhibition of Transglutaminase 2 as a Therapeutic Strategy in Celiac Disease-In Vitro Studies in Intestinal Cells and Duodenal Biopsies

Enzymatic modification of gliadin peptides by human transglutaminase 2 (TG2) is a key mechanism in the pathogenesis of celiac disease (CD) and represents a potential therapeutic target. Recently, we have identified the small oxidative molecule PX-12 as an effective inhibitor of TG2 in vitro. In this study, we further investigated the effect of PX-12 and the established active-site directed inhibitor ERW1041 on TG2 activity and epithelial transport of gliadin peptides. We analyzed TG2 activity using immobilized TG2, Caco-2 cell lysates, confluent Caco-2 cell monolayers and duodenal biopsies from CD patients. TG2-mediated cross-linking of pepsin-/trypsin-digested gliadin (PTG) and 5BP (5-biotinamidopentylamine) was quantified by colorimetry, fluorometry and confocal microscopy. Cell viability was tested with a resazurin-based fluorometric assay. Epithelial transport of promofluor-conjugated gliadin peptides P31-43 and P56-88 was analyzed by fluorometry and confocal microscopy. PX-12 reduced TG2-mediated cross-linking of PTG and was significantly more effective than ERW1041 (10 µM, 15 ± 3 vs. 48 ± 8%, p < 0.001). In addition, PX-12 inhibited TG2 in cell lysates obtained from Caco-2 cells more than ERW1041 (10 µM; 12 ± 7% vs. 45 ± 19%, p < 0.05). Both substances inhibited TG2 comparably in the intestinal lamina propria of duodenal biopsies (100 µM, 25 ± 13% vs. 22 ± 11%). However, PX-12 did not inhibit TG2 in confluent Caco-2 cells, whereas ERW1041 showed a dose-dependent effect. Similarly, epithelial transport of P56-88 was inhibited by ERW1041, but not by PX-12. Cell viability was not negatively affected by either substance at concentrations up to 100 µM. PX-12 did not reduce TG2 activity or gliadin peptide transport in confluent Caco-2 cells. This could be caused by rapid inactivation or degradation of the substance in the Caco-2 cell culture. Still, our in vitro data underline the potential of the oxidative inhibition of TG2. The fact that the TG2-specific inhibitor ERW1041 reduced the epithelial uptake of P56-88 in Caco-2 cells further strengthens the therapeutic potential of TG2 inhibitors in CD.

Incidence of Pediatric Celiac Disease Varies by Region

INTRODUCTION

The Environmental Determinants of Diabetes in the Young study follows an HLA risk selected birth cohort for celiac disease (CD) development using a uniform protocol. Children under investigation come from 6 different regions within Europe and the United States. Our aim was to identify regional differences in CD autoimmunity and CD cumulative incidence for children born between 2004 and 2010.

METHODS

Children (n = 6,628) with DQ2.5 and/or DQ8.1 were enrolled prospectively from birth in Georgia, Washington, Colorado, Finland, Germany, and Sweden. Children underwent periodic study screening for tissue transglutaminase antibodies and then CD evaluation per clinical care. Population-specific estimates were calculated by weighting the study-specific cumulative incidence with the population-specific haplogenotype frequencies obtained from large stem cell registries from each site.

RESULTS

Individual haplogenotype risks for CD autoimmunity and CD varied by region and affected the cumulative incidence within that region. The CD incidence by age 10 years was highest in Swedish children at 3%. Within the United States, the incidence by age 10 years in Colorado was 2.4%. In the model adjusted for HLA, sex, and family history, Colorado children had a 2.5-fold higher risk of CD compared to Washington. Likewise, Swedish children had a 1.4-fold and 1.8-fold higher risk of CD compared with those in Finland and Germany, respectively.

DISCUSSION

There is high regional variability in cumulative incidence of CD, which suggests differential environmental, genetic, and epigenetic influences even within the United States. The overall high incidence warrants a low threshold for screening and further research on region-specific CD triggers.

Osteoporosis and Celiac Disease: Updates and Hidden Pitfalls

Celiac disease (CD) is an autoimmune disorder caused by gluten ingestion in genetically predisposed individuals. In addition to the typical gastrointestinal symptoms (e.g., diarrhea, bloating, and chronic abdominal pain), CD may also present with a broad spectrum of manifestations, including low bone mineral density (BMD) and osteoporosis. The etiopathology of bone lesions in CD is multifactorial and other conditions, rather than mineral and vitamin D malabsorption, may affect skeletal health, especially those related to the endocrine system. Here, we describe CD-induced osteoporosis in an attempt to enlighten new and less-known aspects, such as the influence of the intestinal microbiome and sex-related differences on bone health. This review describes the role of CD in the development of skeletal alterations to provide physicians with an updated overview on this debated topic and to improve the management of osteoporosis in CD.

Prevalence and clinical outcomes of COVID-19 in patients with pre-existing celiac disease: A systematic review and meta-analysis

There is a scarcity of scientific evidence addressing the outcomes of COVID-19 in celiac disease (CD) patients. This systematic review and meta-analysis aimed to evaluate the correlation between pre-existing CD and COVID-19. A rigorous literature search was conducted using multiple databases. All eligible observational studies were included from around the globe. The random effect model calculated the pooled prevalence and associated 95% confidence intervals (CI). Mantel-Haenszel odds ratios were produced to report the overall effect size using random effect models for severity and mortality outcomes. Funnel plots, Egger regression tests, and Begg-Mazumdar's rank correlation test were used to appraise publication bias. Data from 11 articles consisting of 44,378 CD patients were obtained. Overall pooled random-effects estimate of SARS-CoV-2 infection in CD patients was 4.25% (95% CI, I²  = 98%). Our findings also indicated that pre-existing CD was not associated with an increased risk of hospitalisation with COVID-19 illness (OR = 1.04, 95% CI 0.87-1.24, I²  = 0%) and mortality due to illness (OR = 0.92, 95% CI 0.56-1.5, I²  = 45%) compared with patients without pre-existing CD. No significant publication bias was evident in the meta-analysis. The preliminary data from our analysis suggest that SARS-CoV-2 infection in patients with pre-existing CD is not associated with an increased risk of hospitalisation or mortality. Additional studies are required to overcome the restrictions of the limited data available at present.

IgE-Dependent Allergy in Patients with Celiac Disease: A Systematic Review

In order to answer the question if an IgE-mediated allergy (A-IgE) may occur in subjects with celiac disease (CD), a systematic review was performed of available publications collected in the United States National Institute for Biotechnology Information/National Institutes of Health/National Library of Medicine/PubMed database up to 28 December 2022, with the use of the following keywords "allergy&celiac/coeliac", "sensitization&celiac/coeliac", and "anaphylaxis&celiac/coeliac" compared in the form of a conjunction. In total, the search returned 2013 publications from these keywords in any section of the article. As numerous review articles included the above-mentioned entries in the abstract, we decided to focus on the publications with the entries only in the title (n = 63). After rejecting studies unrelated to the topic, narrative reviews, book chapters, conference abstracts, symposium reports, letters to the editor, or non-English articles, 18 publications (6 observational original studies and 12 case reports describing a total of 15 cases of A-IgE developed after a diagnosis of CD) were included to this review. Our study is the first systematic review on allergy occurrence in CD patients. The analysis indicated that the possibility of a coexistence of A-IgE with any food and inhalant allergens in subjects diagnosed with CD should be considered. A sensitization to wheat was the most frequently described in subjects with CD. The clinical manifestation of A-IgE in CD was similar to that in subjects without CD; e.g., with possible atopic dermatitis, vomiting, urticaria, angioedema, or anaphylactic shock. Screening for allergies in subjects with CD should be considered, especially in those cases where symptoms persist after introducing a gluten-free diet. The elimination of wheat from the diet of patients with CD may lead to a loss of immune tolerance and to the development of sensitization, which may even manifest as anaphylaxis. In conclusion, although there are few studies assessing the occurrence of A-IgE in subjects with CD, they show the possibility of a coexistence of both diseases and the high clinical significance of this phenomenon, which indicates the need for further studies.

Gluten Exorphins Promote Cell Proliferation through the Activation of Mitogenic and Pro-Survival Pathways

Celiac disease (CD) is a chronic and systemic autoimmune disorder that affects preferentially the small intestine of individuals with a genetic predisposition. CD is promoted by the ingestion of gluten, a storage protein contained in the endosperm of the seeds of wheat, barley, rye, and related cereals. Once in the gastrointestinal (GI) tract, gluten is enzymatically digested with the consequent release of immunomodulatory and cytotoxic peptides, i.e., 33mer and p31-43. In the late 1970s a new group of biologically active peptides, called gluten exorphins (GEs), was discovered and characterized. In particular, these short peptides showed a morphine-like activity and high affinity for the δ-opioid receptor (DOR). The relevance of GEs in the pathogenesis of CD is still unknown. Recently, it has been proposed that GEs could contribute to asymptomatic CD, which is characterized by the absence of symptoms that are typical of this disorder. In the present work, GEs cellular and molecular effects were in vitro investigated in SUP-T1 and Caco-2 cells, also comparing viability effects with human normal primary lymphocytes. As a result, GEs treatments increased tumor cell proliferation by cell cycle and Cyclins activation as well as by induction of mitogenic and pro-survival pathways. Finally, a computational model of GEs interaction with DOR is provided. Altogether, the results might suggest a possible role of GEs in CD pathogenesis and on its associated cancer comorbidities.

Adherence to the Mediterranean Diet and Ultra-Processed Foods Consumption in a Group of Italian Patients with Celiac Disease

Evidence on the consumption of ultra-processed foods (UPF) in adults with celiac disease (CD) and its impact on Mediterranean Diet (MD) adherence is still limited. Our aim was to determine UPF consumption and its relationship with MD adherence in a group of adults, according to the presence of CD. This case-control study included 103 adults with CD and 312 without CD. UPF intake was assessed using the NOVA Food Frequency Questionnaire (NFFQ), while MD adherence was assessed using the Medi-Lite score. UPF represented 14.5% of the diet of participants with CD (246 g/day) and came mainly from cereals-based products (29%) and sweets (24.2%). UPF consumption did not differ with the presence of CD, but participants with CD had significantly (p < 0.05) higher consumption of precooked pasta and pre-packaged breads. Participants with CD also reported a significantly lower MD adherence than participants without CD (9.4 vs. 10.4), with higher intake of meat and dairy products, and lower consumption of vegetables and fish. An inverse trend was found between UPF consumption and MD adherence in adults with CD, although not statistically significant. These findings highlight the importance of improving nutrition education for subjects with CD, which should not only focus on gluten exclusion.

Risk of obesity during a gluten-free diet in pediatric and adult patients with celiac disease: a systematic review with meta-analysis

CONTEXT

Obesity is a significant risk factor for many pathological conditions. Whether a gluten-free diet (GFD) is a risk factor for overweight or obesity remains controversial.

OBJECTIVE

The primary aim of this study was to assess the prevalence of body mass index (BMI) categories at disease presentation and the variation in BMI category from underweight/normal to overweight/obese and vice versa during a GFD.

DATA SOURCES

PubMed, Scopus, and Web of Science databases were searched through February 2021 for retrospective, cross-sectional, and prospective studies reporting BMI categories at disease diagnosis and during a GFD.

DATA EXTRACTION

Data were extracted by 2 reviewers independently. Disagreements were resolved by consensus; a third reviewer was consulted, if necessary. Risk of bias was assessed with the Cochrane ROBINS-I tool.

DATA ANALYSIS

Subgroup analysis based on age (pediatric/adult patients), study design (prospective, cross-sectional, retrospective), and duration of GFD was performed.. Forty-five studies were selected (7959 patients with celiac disease and 20 524 healthy controls). The mean BMI of celiac patients at presentation was significantly lower than that of controls (P < 0.001). During a GFD, the mean BMI increased significantly (mean difference = 1.14 kg/m2 [95%CI, 0.68-1.60 kg/m2]; I2 = 82.8%; P < 0.001), but only 9% of patients (95%CI, 7%-12%; I2 = 80.0%) changed from the underweight/normal BMI category to the overweight/obese category, while 20% (95%CI, 11%-29%; I2 = 85.8%) moved into a lower BMI category.

CONCLUSION

Most celiac patients had a normal BMI at presentation, although the mean BMI was significantly lower than that of controls. A GFD does not increase the risk of becoming overweight/obese, especially in children. The quality of several studies was suboptimal, with moderate or high overall risk of bias and heterogeneity.

Epstein-Barr Virus-Positive Lymphoepithelioma-Like Carcinoma in Celiac Disease

Lymphoepithelioma-like carcinoma (LELC) is a rare lymphoproliferative malignancy that has been described in many organs over the years. LELC in the duodenum has rarely been described in literature. This article aims to present a rare cause of melena in a young man and the diagnostic challenge that ensued to throw more light on this rare disease. In this article, we describe a 43-year-old man who presented with melena and weight loss and was subsequently diagnosed with LELC after multiple endoscopic biopsies. The patient was also found to have celiac disease in association with his LELC.

The analysis of coexistence of celiac disease and vulvar lichen sclerosus in girls

OBJECTIVES

Vulvar lichen sclerosus (VLS) is a chronic inflammatory disease of unclear etiology. Recent studies show that 15-34% of cases in adult women and 14% in girls coexist with allergies or autoimmune diseases, among others - celiac disease (CD). Most of the research on the coexistence of VLS and autoimmune diseases has been carried out on a group of adult women. Literature data on this issue are very scarce.

MATERIAL AND METHODS

The presented work is a pioneering project in which we tried to elucidate a possible relationship between celiac disease and lichen sclerosus in girls. The aim of the research was to study the antibodies characteristic of celiac disease in girls with VLS. The control group consisted of 35 heathy adolescent girls and the study group consisted of 20 girls aged 2-18 years old diagnosed with vulvar lichen sclerosus recruited at the Gynecological Clinic for Girls at the Women's Health Center in Katowice.

RESULTS

There were no significant differences in the concentrations of antibodies characteristic for CD in the blood serum between the studied groups.

CONCLUSIONS

The main limitation of our study was the small size of the study group. It is therefore legitimate to conduct further research on a larger study group to find themutual correlations between the analyzed antibodies and the onset and the course of VLS in girls. The finding of a positive correlation between the coexistence of VLS and CD may prevent potentially serious, long-term complications.

Microbiota-dependent proteolysis of gluten subverts diet-mediated protection against type 1 diabetes

Diet and commensals can affect the development of autoimmune diseases like type 1 diabetes (T1D). However, whether dietary interventions are microbe-mediated was unclear. We found that a diet based on hydrolyzed casein (HC) as a protein source protects non-obese diabetic (NOD) mice in conventional and germ-free (GF) conditions via improvement in the physiology of insulin-producing cells to reduce autoimmune activation. The addition of gluten (a cereal protein complex associated with celiac disease) facilitates autoimmunity dependent on microbial proteolysis of gluten: T1D develops in GF animals monocolonized with Enterococcus faecalis harboring secreted gluten-digesting proteases but not in mice colonized with protease deficient bacteria. Gluten digestion by E. faecalis generates T cell-activating peptides and promotes innate immunity by enhancing macrophage reactivity to lipopolysaccharide (LPS). Gnotobiotic NOD Toll4-negative mice monocolonized with E. faecalis on an HC + gluten diet are resistant to T1D. These findings provide insights into strategies to develop dietary interventions to help protect humans against autoimmunity.

A Clinical Investigation on ADHD-Traits in Childhood Celiac Disease

OBJECTIVE

There are no definitive results about either the presence of exact comorbidity between celiac disease (CD) and attention-deficit/hyperactivity disorders (ADHD) or etiology. We intend to screen ADHD-related cognitive and behavioral traits in children with biopsy-proven CD and investigate the possible association of these traits with certain vitamin levels, body-mass index, and gluten-free diet (GFD) compliance.

METHOD

A total of 85 children with biopsy-proven CD (the ages of 8-18 years) were compared with age and sex-matched 72 healthy controls in terms of demographics, psychiatric symptoms, certain vitamin levels, and anthropometric measurements.

RESULTS

ADHD-like cognitive issues, such as inattention and learning difficulties, as well as psychosomatic symptoms and poor prosocial behavior, were all associated with GFD noncompliance in childhood CD.

CONCLUSION

Untreated CD may predispose to ADHD-resembling symptoms. Physicians should be aware of the probability of ADHD misdiagnosing due to ADHD-resembling cognitive and behavioral traits in untreated CD.

Malignancies in Patients with Celiac Disease: Diagnostic Challenges and Molecular Advances

Celiac disease (CD) is a multiorgan autoimmune disorder of the chronic intestinal disease group characterized by duodenal inflammation in genetically predisposed individuals, precipitated by gluten ingestion. The pathogenesis of celiac disease is now widely studied, overcoming the limits of the purely autoimmune concept and explaining its hereditability. The genomic profiling of this condition has led to the discovery of numerous genes involved in interleukin signaling and immune-related pathways. The spectrum of disease manifestations is not limited to the gastrointestinal tract, and a significant number of studies have considered the possible association between CD and neoplasms. Patients with CD are found to be at increased risk of developing malignancies, with a particular predisposition of certain types of intestinal cancer, lymphomas, and oropharyngeal cancers. This can be partially explained by common cancer hallmarks present in these patients. The study of gut microbiota, microRNAs, and DNA methylation is evolving to find the any possible missing links between CD and cancer incidence in these patients. However, the literature is extremely mixed and, therefore, our understanding of the biological interplay between CD and cancer remains limited, with significant implications in terms of clinical management and screening protocols. In this review article, we seek to provide a comprehensive overview of the genomics, epigenomics, and transcriptomics data on CD and its relation to the most frequent types of neoplasms that may occur in these patients.

Altered Posttranslational Modification of Microtubules Contributes to Disturbed Enterocyte Morphology in Celiac Disease

Celiac disease (CD) represents a frequent autoimmune disease triggered by the ingestion of gliadin in genetically predisposed individuals. The alteration of enterocytes and brush border membrane morphology have been repetitively demonstrated, but the underlying mechanisms remain unclear. Microtubules represent a major element of the cytoskeleton and exert multiple functions depending on their tyrosination status. The aim of our study was to investigate whether posttranslational modification of microtubules was altered in the context of CD and whether this mechanism contributed to morphological changes of CD enterocytes. We examined the expression of tubulin tyrosine ligase (TTL) and vasohibin-2 (VASH2) and the level of detyrosinated and acetylated tubulin in duodenal biopsies and Caco-2 cells by immunoblot and immunofluorescence microcopy. Electron microscopy was performed to investigate the subcellular distribution of detyrosinated tubulin and brush border membrane architecture in CD biopsies and Madin-Darby Canine Kidney type II (MDCK) cells lacking TTL. CD enterocytes and Caco-2 cells stimulated with digested gliadin or IFN-y displayed a flattened cell morphology. This disturbed cellular architecture was accompanied by an increased amount of detyrosinated and acetylated tubulin and corresponding high expression of VASH2 and low expression of TTL. The altered posttranslational modification of tubulin was reversible after the introduction of the gluten-free diet. CD enterocytes and MDCK cells deficient in TTL displayed a reduced cell height along with an increased cell width and a reduced number of apical microvilli. Our results provide a functional explanation for the observed morphological alterations of the enterocytes observed in CD and provide diagnostic potential of the tyrosination status of microtubules as an early marker of villous atrophy and CD inflammation.

Identification of celiac disease associated IgA nephropathy by IgA anti-tissue transglutaminase2 antibody deposits in archived formalin-fixed tissues

BACKGROUND

The causal association between IgA nephropathy (IgAN) and celiac disease (CeD) is based on their clinical coexistence. In this prospective study, we screened patients with IgAN for CeD and explored the utility of analysis of IgA anti-TG2 antibody deposits, for establishing a causal association.

METHODS

Biopsy-proven patients of IgAN were screened for serum IgA anti-tissue transglutaminase antibody (IgA anti-tTG Ab) titer and thereafter were invited to undergo endoscopic duodenal biopsy. Corresponding duodenal and kidney biopsies were subjected to IgA anti-TG2 antibody colocalization study using dual-color immunohistochemistry and immunofluorescence techniques. Additionally, kidney biopsies from 105 patients with IgAN who did not give consent for serology analysis, 30 non-IgA nephropathies, and 10 normal controls were also included. Dual-color-stained slides were interpreted based on stain distribution and intensity scores, and Pearson's index >0.3-1 on confocal imaging was considered significant.

RESULTS

Of a cohort of 151 patients with IgAN, 32 consented to undergo sero-screening and 5 of them had high serum anti-tTG Ab titer. Two out of the latter consented to endoscopic duodenal biopsies, in whom modified Marsh grade 3b changes were identified. Strong IgA anti-TG2 antibody deposits were noted in the kidney and duodenal biopsies of these patients. One patient out of non-consenting 105 patients with IgAN and 3 out of 30 patients with other non-IgA nephropathies also showed IgA anti-TG2 deposits. None of the healthy kidney tissues showed IgA anti-TG2 Ab deposits.

CONCLUSIONS

Co-localized IgA anti-TG2 deposits in the kidney biopsies in patients with IgAN help to establish a pathogenic link with CeD. A small proportion of patients with IgAN have associated CeD.

Pregnancy- and birth-related risk factors for the development of childhood celiac disease

AIM

To evaluate whether pregnancy and birth-related factors are associated with celiac disease (CD) in a large, United States (US)-based mother-child cohort.

METHODS

We analysed data gathering from the Massachusetts General Hospital Maternal Child Cohort (MMCC) of children born between 1998 and 2016. Data included the mode of delivery, maternal pregnancy and their offspring characteristics. We searched for CD cases by using diagnosis billing codes. Cox proportional hazard regression models were created to identify variables associated with CD.

RESULTS

We identified 44 539 mother-child pairs who had at least one encounter by 5 years old and identified 173 children (0.4%) with CD diagnosis; median age at the diagnosis was 6 years. Overall, the adjusted hazard ratio (aHR) of caesarean delivery for CD was 1.39 (95% CI: 0.99, 1.96, p = 0.06) when compared to children born vaginally. After stratifying for the presence of labour, children born by Caesarean delivery without labour had a higher risk of CD (aHR 1.56; 95%CI: 1.01, 2.41; p = 0.046) while infants born by Caesarean delivery with labour did not (aHR 1.26; 95% CI: 0.83, 1.93; p = 0.28).

CONCLUSION

Being born by Caesarean delivery without labour may be associated with an increased risk for CD in the US children.

Diagnostic performances of celiac disease serological tests among Saudi patients

BACKGROUND

: The prevalence of celiac disease (CD) is relatively high in Saudi Arabia, and little is known about the accuracy of serological markers in the local population. This study aimed to assess the diagnostic performance of various serological markers for detecting CD in Saudi children and adults.

METHODS

We conducted a retrospective study of 148 CD patients and 512 controls to assess the diagnostic performances of IgA anti-tissue transglutaminase antibodies (TTG), IgG anti-TTG, IgA anti-deamidated gliadin peptide antibodies (anti-DGP), IgG anti-DGP, and endomysium antibodies (EMA).

RESULTS

: Immunoglobulin A (IgA) anti-TTG was the most sensitive test [98.9% (95% confidence interval (CI) 94.1-99.8%)], while EMA was the most specific [100%, 95%CI 98.6-100%]. By applying the criteria of IgA anti-TTG titers ≥10 × upper limit of normal (ULN) and positive EMA, 57.3% of patients could have avoided intestinal biopsy. IgG anti-DGP test had a sensitivity of 85.9% (95% CI = 77.3-91.5%) and a specificity of 93.5% (95% CI = (90.0-95.9%). Titers of IgA anti-TTG, IgA anti-DGP, and IgG anti-DGP were higher in CD patients with the Marsh 3c class than in those with the Marsh 3b and Marsh 3a classes. IgG anti-TTG and IgA anti-DGP had no additional diagnostic value.

CONCLUSIONS

: IgA anti-TTG and EMA are excellent CD markers in children and adults. The use of IgA anti-TTG titers ≥10 × ULN and positive EMA as criteria for CD diagnosis in children and adults might be a good alternative to intestinal biopsy.

Gluten-Free Diet and Metabolic Syndrome: Could Be a Not Benevolent Encounter?

Celiac disease is a rising disorder and is becoming frequently diagnosed in recent years. To date, the only available treatment is the gluten-free diet (GFD). The role of gluten on components of metabolic syndrome and on related inflammatory response is still unclear due to controversial results. In recent years, scientific focus on this topic has been growing up, in particular regarding the role of the GFD on glycometabolic parameters and diabetes. In addition, studies on the remaining components showed discordant results, which was likely due to heterogeneous and large celiac disease populations and to the lack of prospective studies. Furthermore, knowledge about the role of the GFD on inflammatory cytokines and the relationship among vitamin D and celiac disease, metabolic syndrome (MS) and GFD is needed. In this narrative review, we provided evidence regarding the role of the GFD on glycometabolic parameters, cholesterol, triglycerides, waist circumference, blood pressure and inflammatory cascade, also evaluating the role of vitamin D, trying to summarize whether this nutritional pattern may be a value-added for subjects with dysmetabolic conditions. Finally, due to the limited findings and very low-certainty evidence, predominantly based on observational studies, the real effects of a GFD on different components of MS, however, are unclear; nevertheless, an improvement in HDL levels has been reported, although data on glycemic levels are discordant.

The Immunobiology and Pathogenesis of Celiac Disease

Among human leukocyte antigen (HLA)-associated disorders, celiac disease has an immunopathogenesis that is particularly well understood. The condition is characterized by hypersensitivity to cereal gluten proteins, and the disease lesion is localized in the gut. Still, the diagnosis can be made by detection of highly disease-specific autoantibodies to transglutaminase 2 in the blood. We now have mechanistic insights into how the disease-predisposing HLA-DQ molecules, via presentation of posttranslationally modified gluten peptides, are connected to the generation of these autoantibodies. This review presents our current understanding of the immunobiology of this common disorder that is positioned in the border zone between food hypersensitivity and autoimmunity.

The Influence of SARS-CoV-2 Pandemic on the Diagnosis of Celiac Disease and Clinical Practice in Pediatric Gastroenterology

Celiac disease (CD) has a high prevalence but remains largely underdiagnosed. Although extensive studies have confirmed that children with CD do not have an increased risk of severe COVID-19, public health regulations associated with the SARS-CoV-2 pandemic may have exacerbated this problem. The aim of this study was to assess the effect of SARS-CoV-2 on the number of new-onset CD cases. Additionally, the role of SARS-CoV-2 in autoimmune diseases and its influence on clinical practice in pediatric gastroenterology were briefly reviewed. We described the data from the hospital electronic registry of new-onset CD, during the COVID-19 pandemic and 2 years before. A total of 423 children were diagnosed with CD between March 2018 and February 2022: 228 in the 2-year pre-COVID-19 period and 195 during the pandemic. The number of patients during the COVID-19 pandemic was 14.5% lower than in the previous years. The quarterly comparison of CD diagnoses showed a reduction in all quarters. A reduction in diagnoses during the lockdown and in the following months was evident and not compensated thereafter. This is the first study to evaluate the impact of SARS-CoV-2 on the diagnosis of CD in children. Further studies are necessary to improve the system of biopsy-sparing diagnosis and to evaluate the effect of the diagnostic delay. Special attention should be given to the implementation of telemedicine services.

Why are western diet and western lifestyle pro-inflammatory risk factors of celiac disease?

The prevalence of celiac disease increased in recent years. In addition to the genetic and immunological factors, it appears that environmental determinants are also involved in the pathophysiology of celiac disease. Gastrointestinal infections impact the development of celiac disease. Current research does not directly confirm the protective effect of natural childbirth and breastfeeding on celiac disease. However, it seems that in genetically predisposed children, the amount of gluten introduced into the diet may have an impact on celiac disease development. Also western lifestyle, including western dietary patterns high in fat, sugar, and gliadin, potentially may increase the risk of celiac disease due to changes in intestinal microbiota, intestinal permeability, or mucosal inflammation. Further research is needed to expand the knowledge of the relationship between environmental factors and the development of celiac disease to define evidence-based preventive interventions against the development of celiac disease. The manuscript summarizes current knowledge on factors predisposing to the development of celiac disease including factors associated with the western lifestyle.

Celiac Disease Genetics, Pathogenesis, and Standard Therapy for Japanese Patients

Celiac disease is an autoimmune disease primarily affecting the small intestine that is caused by the ingestion of gluten in genetically susceptible individuals. The development of celiac disease is based on a complex immune response to gluten proteins. The global average prevalence in the general population is about 1%. In recent years, it has become clear that celiac disease is not less common in Asian countries than in Western countries but often remains undiagnosed. Although the number of patients with celiac disease in Asia is expected to increase with improving disease recognition and advances in diagnostic techniques, there remain few reports of celiac disease in the Far East region of Asia, especially in Japan. In this paper, we outline the epidemiology, diagnosis, and treatment of celiac disease. In addition, we summarize the reported Japanese cases of celiac disease with an overview in Japan.

A meta-analysis suggests the association of reduced serum level of vitamin D and T-allele of Fok1 (rs2228570) polymorphism in the vitamin D receptor gene with celiac disease

Purpose

As an immune-modulator, vitamin D is known to regulate immune response and is implicated in disease pathogenesis. Celiac disease (CD) is a systemic autoimmune disease and susceptibility conferred by vitamin D metabolism is under investigation. Studies on the association of vitamin D metabolism and genetic polymorphisms are expected to explain CD pathogenesis. We performed a systematic review-based meta-analysis to investigate the 25(OH)D serum levels and susceptibility conferred by the genetic variants of VDR in CD.

Methods

Systematic review was conducted through a web-based literature search following stringent study inclusion-exclusion criteria. The Newcastle-Ottawa Scale and GRADE tools were used to assess the quality of evidence in studies and the study outcome. Cohen's κ value was estimated to access the reviewer's agreement. RevMan 5.4.1 was used to perform the meta-analyses. Weighted mean difference and Meta p-value was assessed for 25(OH)D serum levels. Meta-odds ratio and Z-test p-value were evaluated to estimate the allelic susceptibility of VDR variants.

Results

A total of 8 out of 12 studies were evaluated for "25(OH)D" serum level, while four studies were found eligible for SNPs (Bsm1, Apa1, Fok1, and Taq1) of VDR. Significantly higher levels [WMD = 5.49, p < 0.00001] of 25(OH)D were observed in healthy controls than in patients with CD. rs2228570-T (Fok1) [Meta-OR = 1.52, p = 0.02] was confirmed to be predisposing allele for CD.

Conclusion

Reduced serum level of 25(OH)D and association of Fok1 T-allele of VDR confirmed in this study plays a critical role in immunomodulation and maintaining barrier integrity, which is majorly implicated in CD.

LRP-1 links post-translational modifications to efficient presentation of celiac disease-specific T cell antigens

Celiac disease (CeD) is an autoimmune disorder in which gluten-derived antigens trigger inflammation. Antigenic peptides must undergo site-specific deamidation to be presentable to CD4+ T cells in an HLA-DQ2 or -DQ8 restricted manner. While the biochemical basis for this post-translational modification is understood, its localization in the patient's intestine remains unknown. Here, we describe a mechanism by which gluten peptides undergo deamidation and concentration in the lysosomes of antigen-presenting cells, explaining how the concentration of gluten peptides necessary to elicit an inflammatory response in CeD patients is achieved. A ternary complex forms between a gluten peptide, transglutaminase-2 (TG2), and ubiquitous plasma protein α2-macroglobulin, and is endocytosed by LRP-1. The covalent TG2-peptide adduct undergoes endolysosomal decoupling, yielding the expected deamidated epitope. Our findings invoke a pathogenic role for dendritic cells and/or macrophages in CeD and implicate TG2 in the lysosomal clearance of unwanted self and foreign extracellular proteins.

Prediction of celiac disease associated epitopes and motifs in a protein

Introduction

Celiac disease (CD) is an autoimmune gastrointestinal disorder causes immune-mediated enteropathy against gluten. Gluten immunogenic peptides have the potential to trigger immune responses which leads to damage the small intestine. HLA-DQ2/DQ8 are major alleles that bind to epitope/antigenic region of gluten and induce celiac disease. There is a need to identify CD associated epitopes in protein-based foods and therapeutics.

Methods

In this study, computational tools have been developed to predict CD associated epitopes and motifs. Dataset used for training, testing and evaluation contain experimentally validated CD associated and non-CD associate peptides. We perform positional analysis to identify the most significant position of an amino acid residue in the peptide and checked the frequency of HLA alleles. We also compute amino acid composition to develop machine learning based models. We also developed ensemble method that combines motif-based approach and machine learning based models.

Results and Discussion

Our analysis support existing hypothesis that proline (P) and glutamine (Q) are highly abundant in CD associated peptides. A model based on density of P&Q in peptides has been developed for predicting CD associated peptides which achieve maximum AUROC 0.98 on independent data. We discovered motifs (e.g., QPF, QPQ, PYP) which occurs specifically in CD associated peptides. We also developed machine learning based models using peptide composition and achieved maximum AUROC 0.99. Finally, we developed ensemble method that combines motif-based approach and machine learning based models. The ensemble model-predict CD associated motifs with 100% accuracy on an independent dataset, not used for training. Finally, the best models and motifs has been integrated in a web server and standalone software package "CDpred". We hope this server anticipate the scientific community for the prediction, designing and scanning of CD associated peptides as well as CD associated motifs in a protein/peptide sequence (https://webs.iiitd.edu.in/raghava/cdpred/).

Phenolic Profile and In Vitro Antioxidant Activity of Different Corn and Rice Varieties

Celiac disease (CD) is an autoimmune disease. To date, the only universally recognized treatment for CD is the gluten-free diet (GFD). Despite the GFD, a state of inflammation and oxidative stress could remain at the intestinal level of celiac patients. Several components of the diet, such as phenolic compounds with known antioxidant properties, could play a protective role in the inflammatory state of patients with CD. The objective of this study was the characterization of the phenolic profile and the antioxidant capacity of pigmented cereals (rice and corn) from the Italian market and farms. Different in vitro methods were applied: Folin-Ciocalteu assay, pH differential method, DPPH assay, TEAC assay, and High-Performance Thin Layer Chromatography technique. According to the results, pigmented varieties are possible valuable sources of phenolic compounds and anthocyanins with high antioxidant activity. They could be used as alternative ingredients for the formulation of gluten-free products.

Analytical and functional approaches to assess the immunogenicity of gluten proteins

Gluten proteins are the causative agents of celiac disease (CD), a lifelong and worldwide spread food intolerance, characterized by an autoimmune enteropathy. Gluten is a complex mixture of high homologous water-insoluble proteins, characterized by a high content of glutamine and proline amino acids that confers a marked resistance to degradation by gastrointestinal proteases. As a consequence of that, large peptides are released in the gut lumen with the potential to activate inflammatory T cells, in CD predisposed individuals. To date, several strategies aimed to detoxify gluten proteins or to develop immunomodulatory drugs to recover immune tolerance to gluten are under investigation. This review overviews the state of art of both analytical and functional methods currently used to assess the immunogenicity potential of gluten proteins from different cereal sources, including native raw seed flours and complex food products, as well as drug-treated samples. The analytical design to assess the content and profile of gluten immunogenic peptides, described herein, is based on the oral-gastro-intestinal digestion (INFOGEST model) followed by extensive characterization of residual gluten peptides by proteomic and immunochemical analyses. These approaches include liquid chromatography-high-resolution mass spectrometry (LC-MS/MS) and R5/G12 competitive ELISA. Functional studies to assess the immune stimulatory capabilities of digested gluten peptides are based on gut mucosa T cells or peripheral blood cells obtained from CD volunteers after a short oral gluten challenge.

MAFLD and Celiac Disease in Children

Celiac disease (CD) is an immune-mediated systemic disorder elicited by the ingestion of gluten whose clinical presentation ranges from the asymptomatic form to clinical patterns characterized by multiple systemic involvement. Although CD is a disease more frequently diagnosed in patients with symptoms of malabsorption such as diarrhea, steatorrhea, weight loss, or failure to thrive, the raised rate of overweight and obesity among general pediatric and adult populations has increased the possibility to diagnose celiac disease in obese patients as well. Consequently, it is not difficult to also find obesity-related disorders in patients with CD, including "metabolic associated fatty liver disease" (MAFLD). The exact mechanisms linking these two conditions are not yet known. The going assumption is that a gluten-free diet (GFD) plays a pivotal role in determining an altered metabolic profile because of the elevated content of sugars, proteins, saturated fats, and complex carbohydrates, and the higher glycemic index of gluten-free products than gluten-contained foods, predisposing individuals to the development of insulin resistance. However, recent evidence supports the hypothesis that alterations in one of the components of the so-called "gut-liver axis" might contribute to the increased afflux of toxic substances to the liver triggering the liver fat accumulation and to the subsequent hepatocellular damage. The aim of this paper was to describe the actual knowledge about the factors implicated in the pathogenesis of hepatic steatosis in pediatric patients with CD. The presented review allows us to conclude that the serological evaluations for CD with anti-transglutaminase antibodies, should be a part of the general workup in the asymptomatic patients with "non-alcoholic fatty liver disease" (NAFLD) when metabolic risk factors are not evident, and in the patients with steatohepatitis when other causes of liver disease are excluded.

Pancreatic Cancer in Celiac Disease Patients-A Systematic Review and Meta-Analysis

Background: Celiac disease (CD) is an autoimmune enteropathy affecting approximately 1% of the population and is associated with an increased risk of enteropathy-associated T-cell lymphoma and small bowel adenocarcinoma, whereas the association between CD and other malignancies is unclear. Since pancreatic cancer (PC) remains one of the most lethal neoplasms and its incidence is increasing despite numerous ongoing research on diagnostic biomarkers and novel therapies, we aimed to investigate whether CD has an impact on the risk of PC. Material and Methods: We performed a systematic review of the literature published from January 2000 to March 2022 in two databases: Web of Science and Scopus and a meta-analysis of eligible studies. Results: Our search identified eight publications included in the systematic review. A total of five studies involving 47,941 patients, including 6399 CD patients with malignancies and 1231 PC cases were included in the meta-analysis and 221 cases of PC in CD patients with other cancers were recognized. The pooled OR for PC was 1.46 (95% CI 1.26−1.7) with significant heterogeneity (89.1%; p < 0.05), suggesting that CD patients with malignancies were at higher risk for PC. Conclusions: The association between CD and PC is uncertain. However, the results of the current meta-analysis may indicate an increased risk of PC in the group of patients with CD and other cancers. Further multicenter studies are warranted.

Peculiar Ca2+ Homeostasis, ER Stress, Autophagy, and TG2 Modulation in Celiac Disease Patient-Derived Cells

Celiac disease (CD) is an inflammatory intestinal disease caused by the ingestion of gluten-containing cereals by genetically predisposed individuals. Constitutive differences between cells from CD patients and control subjects, including levels of protein phosphorylation, alterations of vesicular trafficking, and regulation of type 2 transglutaminase (TG2), have been reported. In the present work, we investigated how skin-derived fibroblasts from CD and control subjects responded to thapsigargin, an endoplasmic reticulum ER stress inducer, in an attempt to contribute to the comprehension of molecular features of the CD cellular phenotype. We analyzed Ca²⁺ levels by single-cell video-imaging and TG2 activity by a microplate assay. Western blots and PCR analyses were employed to monitor TG2 levels and markers of ER stress and autophagy. We found that the cytosolic and ER Ca²⁺ level of CD cells was lower than in control cells. Treatments with thapsigargin differently activated TG2 in control and CD cells, as well as caused slightly different responses regarding the activation of ER stress and the expression of autophagic markers. On the whole, our findings identified further molecular features of the celiac cellular phenotype and highlighted that CD cells appeared less capable of adapting to a stress condition and responding in a physiological way.

GATA4 controls regionalization of tissue immunity and commensal-driven immunopathology

There is growing recognition that regionalization of bacterial colonization and immunity along the intestinal tract has an important role in health and disease. Yet, the mechanisms underlying intestinal regionalization and its dysregulation in disease are not well understood. This study found that regional epithelial expression of the transcription factor GATA4 controls bacterial colonization and inflammatory tissue immunity in the proximal small intestine by regulating retinol metabolism and luminal IgA. Furthermore, in mice without jejunal GATA4 expression, the commensal segmented filamentous bacteria promoted pathogenic inflammatory immune responses that disrupted barrier function and increased mortality upon Citrobacter rodentium infection. In celiac disease patients, low GATA4 expression was associated with metabolic alterations, mucosal Actinobacillus, and increased IL-17 immunity. Taken together, these results reveal broad impacts of GATA4-regulated intestinal regionalization on bacterial colonization and tissue immunity, highlighting an elaborate interdependence of intestinal metabolism, immunity, and microbiota in homeostasis and disease.

Meta-Analysis and Systematic Review of HLA DQ2/DQ8 in Adults with Celiac Disease

Although people with human leukocyte antigens (HLA) DQ2 and/or DQ8 are more likely to develop celiac disease (CD), the condition cannot be fully explained by this genetic predisposition alone. Multiple, as yet unidentified, factors contribute to the genesis of CD, including genetics, the environment, and the immune system. In order to provide insight into a prospective possibility and an expanded screening technique, we aim to undertake a comprehensive and meta-analytical study of the assessment and distribution of HLA class II (HLA-DQ2/DQ8) in adult CD patients. A systematic review was conducted using an electronic search of databases (PubMed, Google Scholar, Embase, and Direct Science) from January 2004 to February 2022. DQ2/DQ2 homozygotes have the highest risk of developing CD. DQ2/DQ8 typing is an effective test to exclude CD from the differential diagnosis of a patient with CD symptoms. Although other non-HLA genes have been associated with CD, they are rarely considered at diagnosis because they account for only a small proportion of the heritability of CD. This finding, together with the information gathered previously, may be useful in considering widely available and economically feasible screening options for celiac disease in young people.

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.

New Developments in Celiac Disease Treatment

Celiac disease (CD) is a common autoimmune disease affecting around 1% of the population. It consists of an immune-mediated enteropathy, triggered by gluten exposure in susceptible patients. All patients with CD, irrespective of the presence of symptoms, must endure a lifelong gluten-free diet (GFD). This is not an easy task due to a lack of awareness of the gluten content in foods and the extensive incorporation of gluten in processed foods. Furthermore, a GFD imposes a sense of limitation and might be associated with decreased quality of life in CD patients. This results in gluten contamination in the diet of four out of five celiac patients adhering to a GFD. Furthermore, one in three adult patients will report persistent symptoms and two in three will not achieve full histological recovery when on a GFD. In recent years, there has been extensive research conducted in the quest to find the holy grail of pharmacological treatment for CD. This review will present a concise description of the current rationale and main clinical trials related to CD drug therapy.

The Effect of a Gluten-Free Diet on Vitamin D Metabolism in Celiac Disease: The State of the Art

Celiac disease is a chronic autoimmune disorder involving the small intestine, characterized by villous atrophy, crypt hyperplasia and an increase in intraepithelial lymphocytes. Due to both calcium malabsorption and immune activation, a high prevalence of bone mass derangement is evident in this condition, regardless of the presence of overt malabsorption. Alterations of mineral metabolism are also frequently described, and in this review, the modifications of serum levels of vitamin D are analyzed, according to the available literature on this topic. In untreated patients, secondary hyperparathyroidism is responsible for the hyperconversion of 25-vitamin D into 1,25-vitamin D making mandatory the determination of serum levels of both vitamin metabolites to avoid a wrong diagnosis of vitamin D deficit. A gluten-free diet allows for a normalization of bone and mineral metabolism, reverting these abnormalities and raising some doubts on the need for vitamin supplementation in all the patients. Data available do not support this wide indication, and a complete evaluation of bone and mineral metabolism should be performed to select patients who need this therapeutic approach.

The effectiveness of gluten-free dietary interventions: A systematic review

Celiac disease is a chronic autoimmune gastroenterological disorder in which the digestion of gluten leads to damage and constant inflammation in the small intestine. Moreover, there are associated physical and mental health problems related to celiac disease, i.e., a lower health-related quality of life and increased depression and anxiety symptoms. The only effective treatment for celiac disease is lifelong adherence to a gluten-free diet. However, researchers suggest that strict adherence to a gluten-free diet ranges from 42 to 80%, depending on the definition and method of assessment that was utilized. This review examines interventions designed for those who need to adhere to life-long dietary measures and their success in terms of increasing gluten-free dietary adherence and improving their health-related quality of life. In April 2022, the Scopus, Web of Science, PubMed and ProQuest databases were searched using the following terms: "coeliac disease" OR "celiac disease" AND "gluten free diet" AND "intervention" AND "health related quality of life" AND "diabetes." Eight studies were suitable for this review. The studies were used to analyze different intervention techniques and their impact on gluten-free dietary adherence, quality of life, and the reasons for dietary nonadherence. The studies revealed statistically significant improvements in the knowledge base regarding celiac disease and the gluten-free diet, dietary adherence and quality-of-life satisfaction immediately after the intervention and at a three-month follow-up. Some studies were also focused on behavioral and cognitive aspects of nonadherence to dietary measures.

Dietary Management of Type 1 Diabetes Mellitus with Celiac Disease

Celiac disease is diagnosed more commonly with type 1 diabetes, and the most problematic aspect for a child with type 1 diabetes and celiac disease is that most GFD foods have a high glycemic index, while low glycemic index foods are recommended for type 1 diabetes mellitus. As a result, dietary controls become more difficult. Diet management could improve the elevated HbA1c levels. The aim of this review is to illustrate the clinical features and diagnostic considerations, as well as current knowledge of common pathogenic features such as genetics, environmental risk factors, and the gut microbiome of type 1 diabtes and celiac disease. Also, the importance of diet management on glycemic control and growth rate in patients with type 1 diabetes mellitus and celiac disease has been discussed. PubMed and Google Scholar databases were searched. Reports published from the years 1969 to 2021 focused on the role of type 1 diabetes mellitus and celiac disease, and examined the types of diet on glycemic control, growth rate, and quality of life. Only a few studies on the effects of a carbohydrate count gluten-free diet on glycemic control, growth rate, and quality of life in patients with type 1 diabetes mellitus and celiac disease have been conducted. There have been few studies showing that dietary intervention helps to achieve and maintain normal blood glucose and blood pressure levels, a healthy lipid profile, and a healthy body weight. Studies stated that a low-carbohydrate diet had the greatest effect on improving glycemic control and insulin parameters.