Epidemic of coeliac disease in Swedish children

Relationship between vitamin D levels and pediatric celiac disease: a systematic review and meta-analysis

BACKGROUND

The relationship between Vitamin D levels and pediatric celiac disease (CD) remains controversial. In this study, we conducted a systematic review and meta-analysis to examine the relationship between Vitamin D and pediatric CD.

METHODS

We screened relevant studies from PubMed, EMBASE, and Web of Science published in English from January 1, 2000, to August 1, 2023. The included studies were assessed according to the STROBE checklist. Heterogeneity was quantified by Cochran's Q test and the I2 statistic. Publication bias was estimated by Begg's test and Egger's test. Meta-regression was used to detect potential sources of heterogeneity.

RESULTS

A total of 26 studies were included in the meta-analysis. Nineteen articles compared 25(OH)D3 levels between CD patients and control groups, average 25-hydroxyvitamin D3 [25(OH)D3 or calcidiol], and 1,25-dihydroxyvitamin D3 [1,25(OH)2D3 or calcitriol] levels, as the main forms of Vitamin D, there was a significant difference in CD patients and healthy controls (weighted mean difference (WMD) = - 5.77, 95% confidence interval (CI) = [- 10.86, - 0.69] nmol/L). Meanwhile, eleven articles reported the numbers of patients and controls with Vitamin D deficiency, there was a significant difference in the incidence of 25(OH)D3 deficiency between CD patients and healthy controls (odds ratio 2.20, 95% CI= [1.19, 4.08]). Nine articles reported changes in 25(OH)D3 levels before and after administering a GFD in patients with CD, the result of this study revealed the increase of 25(OH)D3 levels in CD patients after a gluten-free diet (GFD) (WMD = - 6.74, 95% CI = [- 9.78, - 3.70] nmol/L).

CONCLUSIONS

Vitamin D levels in pediatric CD patients were lower than in healthy controls, and 25(OH)D3 deficiency was more prevalent in CD patients. We found that 25(OH)D3 levels were elevated in CD patients after GFD, which is consistent with previous research. Further well-designed, longitudinal, prospective cohort studies focusing on the role of Vitamin D in the pathogenesis of CD are therefore needed.

Cumulative incidence of type 1 diabetes in two cohorts of children with different national gluten recommendations in infancy

AIMS

Between 1985 and 1996, Sweden experienced an "epidemic" of celiac disease with a fourfold increase in incidence in young children. Timing and amount of gluten introduced during infancy have been thought to explain this "epidemic". We aimed to study whether the cumulative incidence of type 1 diabetes differs between children born during the "epidemic" compared to children born after.

METHODS

This is a national register study in Sweden comparing the cumulative incidence of type 1 diabetes in two birth cohorts of 240 844 children 0-17 years old born 1992-1993, during the "epidemic", and 179 530 children born 1997-1998, after the "epidemic". Children diagnosed with type 1 diabetes were identified using three national registers.

RESULTS

The cumulative incidence of type 1 diabetes by the age of 17 was statistically significantly higher in those born after the "epidemic" 0.77% than in those born during the "epidemic" 0.68% (p < 0.001).

CONCLUSION

The incidence of type 1 diabetes is higher in those born after the epidemic compared to those born during the epidemic, which does not support the hypothesis that gluten introduction increases the incidence of T1D. Changes in gluten introduction did not halt the increased incidence of type 1 diabetes in Sweden.

Are Tp-e interval and QT dispersion values important in children with coeliac disease?

OBJECTIVES

Coeliac disease is an autoimmune intestinal disease that develops with permanent intolerance to gluten and similar cereal proteins. It can damage to many tissues, including myocardium, by autoimmune mechanisms. In our study, we aimed to investigate the effect of coeliac disease on cardiac electrical activity by comparing the Tp-e interval and Qt dispersion values of coeliac patients with healthy children.

METHODS

Fifty-seven coeliac patients and 57 healthy children were included in the study. Sociodemographic findings, physical examinations, symptoms, laboratory values, dietary compliance, endoscopy, and pathological findings were recorded into a standardised form. Electrocardiogram parameters were calculated, and echocardiography findings were noted.

RESULTS

No statistically significant difference was found between the two groups in terms of age, gender, heart rate, electrocardiogram parameters such as p wave, PR interval, QRS complex, QT interval, and QTc values. Tp-e interval, Tp-e / QT ratio, and Tp-e / QTc ratio were statistically significantly higher in the patient group compared to the control group. Ejection fraction and fractional shortening values were significantly lower in the patient group compared to the control group. In the patient group, Tp-e interval, Tp-e / QT ratio, Tp-e / QTc ratio, and QTc dispersion were statistically significantly higher in patients with tissue transglutaminase IgA positive compared to patients with tissue transglutaminase IgA negative.

CONCLUSION

Our study gives important findings in terms of detecting early signs of future cardiovascular events in childhood age group coeliac patients.

Intervention strategies in early childhood to prevent celiac disease-a mini-review

A higher intake of gluten during childhood is associated with increased risk of celiac disease, and the incidence of celiac disease peaks shortly after the time point when associations with higher gluten intake during the second and third year of life occur. Additional environmental factors are most likely necessary for celiac disease to develop. It is hypothesized that gastrointestinal infections increase gut permeability and exposure to gluten. Alternatively, infections may lead to gut dysbiosis and chronic inflammation, with leakage of self-antigens that mimic gluten peptides that leads to an autoimmune-like response. Different gluten interventions to prevent celiac disease have been proposed. Early clinical studies suggested an optimal time point introducing gluten between 4 and 6 months of age while the infant is being breastfed. However, later clinical trials on reduced gluten intake given to infants have shown no protection from celiac disease if gluten introduction was delayed or if gluten was introduced in small amounts during the child's first year of life. Still, more randomized clinical trials (RCTs) are warranted to answer the question if a reduced amount of gluten, not only at the time of introduction during infancy but also in a longer time frame, will prevent children at genetic risk from having lifelong celiac disease. It needs to be clarified whether dietary interventions are effective strategies to be proposed as future prevention of celiac disease in the general population. The present mini-review provides an overview of ongoing or completed RCTs that have focused on interventions during early childhood with the aim of preventing celiac disease.

Sources of dietary gluten in the first 2 years of life and associations with celiac disease autoimmunity and celiac disease in Swedish genetically predisposed children: The Environmental Determinants of Diabetes in the Young (TEDDY) study

BACKGROUND

High gluten intake is associated with increased risk of celiac disease (CD) in children at genetic risk.

OBJECTIVES

We aimed to investigate if different dietary gluten sources up to age 2 y confer different risks of celiac disease autoimmunity (CDA) and CD in children at genetic risk.

METHODS

Three-day food records were collected at ages 6, 9, 12, 18, and 24 mo from 2088 Swedish genetically at-risk children participating in a 15-y follow-up cohort study on type 1 diabetes and CD. Screening for CD was performed with tissue transglutaminase autoantibodies (tTGA). The primary outcome was CDA, defined as persistent tTGA positivity. The secondary outcome was CD, defined as having a biopsy specimen showing Marsh score ≥ 2 or an averaged tTGA level ≥ 100 Units. Cox regression adjusted for total gluten intake estimated HRs with 95% CIs for daily intake of gluten sources.

RESULTS

During follow-up, 487 (23.3%) children developed CDA and 242 (11.6%) developed CD. Daily intake of ≤158 g porridge at age 9 mo was associated with increased risk of CDA (HR: 1.53; 95% CI: 1.05, 2.23; P = 0.026) compared with no intake. A high daily bread intake (>18.3 g) at age 12 mo was associated with increased risk of both CDA (HR: 1.47; 95% CI: 1.05, 2.05; P = 0.023) and CD (HR: 1.79; 95% CI: 1.10, 2.91; P = 0.019) compared with no intake. At age 18 mo, milk cereal drink was associated with an increased risk of CD (HR: 1.16; 95% CI: 1.00, 1.33; P = 0.047) per 200-g/d increased intake. No association was found for other gluten sources up to age 24 mo and risk of CDA or CD.

CONCLUSIONS

High daily intakes of bread at age 12 mo and of milk cereal drink during the second year of life are associated with increased risk of both CDA and CD in genetically at-risk children.

Spanish National Registry of Paediatric Coeliac Disease: Changes in the Clinical Presentation in the 21st Century

OBJECTIVES

Over the last several decades, there has been a tendency towards a predominance of less symptomatic forms of coeliac disease (CD) and an increase in the patient age at diagnosis. This study aimed to assess the clinical presentation and diagnostic process of paediatric CD in Spain.

METHODS

A nationwide prospective, observational, multicentre registry of new paediatric CD cases was conducted from January 2011 to June 2017. The data regarding demographic variables, type of birth, breast-feeding history, family history of CD, symptoms, height and weight, associated conditions, serological markers, human leukocyte antigen (HLA) phenotype, and histopathological findings were collected.

RESULTS

In total, 4838 cases (61% girls) from 73 centres were registered. The median age at diagnosis was 4 years. Gastrointestinal symptoms were detected in 71.4% of the patients, and diarrhoea was the most frequent symptom (45.9%). The most common clinical presentation was the classical form (65.1%) whereas 9.8% ofthe patients were asymptomatic. There was a trend towards an increase in the age at diagnosis, proportion of asymptomatic CD cases, and usage of anti-deamidated gliadin peptide antibodies and HLA typing for CD diagnosis. There was, however, a decreasing trend in the proportion of patients undergoing biopsies. Some of these significant trend changes may reflect the effects of the 2012 ESPGHAN diagnosis guidelines.

CONCLUSIONS

Paediatric CD in Spain is evolving in the same direction as in the rest of Europe, although classical CD remains the most common presentation form, and the age at diagnosis remains relatively low.

Two waves of coeliac disease incidence in Sweden: a nationwide population-based cohort study from 1990 to 2015

OBJECTIVES

To assess the incidence of biopsy-verified coeliac disease (CD) in Sweden and examine the incidence of duodenal/jejunal biopsies with normal mucosa over time as a proxy for CD awareness and investigation.

DESIGN

Nationwide population-based cohort study 1990-2015 based on biopsy reports indicating villous atrophy (VA) or normal mucosa in the duodenum/jejunum.

RESULTS

We identified 44 771 individuals (63% females) with a biopsy report specifying VA and 412 279 (62% females) with a biopsy report indicating normal mucosa (without a prior biopsy indicating VA). The median age at diagnosis of CD was 28 years. The mean age-standardised incidence rate during the study period was 19.0 per 100 000 person-years (95% CI 17.3 to 20.8). The incidence reached a peak in 1994 for both sexes and a second higher peak in 2002-2003 for females and in 2006 for males. The lifetime risk of developing CD was 1.8% (2.3% in females and 1.4% in males).Prior to 2015, there was a parallel rise in rates for biopsies showing normal duodenal/jejunal mucosa.

CONCLUSIONS

In Sweden, the incidence of CD increased until 2002-2003 in females and until 2006 in males. Since then, the incidence of CD has declined despite increasing duodenal/jejunal biopsies, suggesting that increased awareness and investigation are unlikely to elevate the incidence of the disease in Sweden. Across a lifetime, 1 in 44 females and 1 in 72 males are expected to be diagnosed with CD in Sweden, indicating a relatively high societal burden of disease.

Next generation strategies to recover immunological tolerance in celiac disease

Celiac disease (CD) is an autoimmune disease that occurs in genetically predisposed individuals following the ingestion of gluten. Its prevalence is rising worldwide. A gluten-free (GF) diet is mandatory for the management of CD. However, several issues persist regarding the nutritional quality of GF products. Importantly, deep knowledge about the pathogenic mechanisms in CD highlights the central role of CD4⁺ T cell-mediated immunity in CD. Furthermore, intestinal T regulatory cells are functional in CD, but cytokines such as IL-15, produced under inflammatory conditions, hamper their activity. This paves the way for the development of immunomodulatory strategies to the GF diet. From this perspective, microbiological approaches were considered able to modulate the gluten-specific immune response. Interestingly, gliadin peptide-based immunotherapy to abolish the inflammatory CD4⁺T cell-mediated response has been explored in CD patients. Furthermore, different biotechnological approaches based on the use of chemically/enzymatically modified gluten molecules have been proved effective in different models of CD. However, the choice of the right age in infants to introduce the antigen and thus induce tolerance still remains an important issue to solve. Addressing all these points should help to design an effective intervention strategy for preventing CD.

Transfer of knowledge to diagnose infant abuse and its incidence - a time-series analysis from Sweden

Aim

To analyse the transfer of knowledge on how to detect physical abuse, especially shaken baby syndrome/abusive head trauma (SBS/AHT), and its association to trends in infant abuse diagnoses (maltreatment and assault).

Methods

Design: retrospective population-based and quasi-experimental. Setting: Sweden 1987–2019. Patients: Children below age 1 year, selected from the National Patient Register (n = 1150). Exposures: Literature search for transfer of knowledge by diffusion, dissemination and implementation, and whether supportive or disruptive of the SBS/AHT paradigm. Main outcome measure: Abuse diagnoses (maltreatment or assault). Analyses: Incidence rate, incidence rate ratio (IRR).

Results

The overall incidence rate of abuse was 32.23 per 100,000 during the years 1987–2019. It was rather stable 1987–2000. The SBS diagnosis was introduced in the late 1990s. A comprehensive increase of transfer of knowledge on physical abuse, specifically on SBS/AHT and dangers of shaking, took place from 2002 and onward through diffusion, dissemination and implementation. Maltreatment diagnoses, but not assault diagnosis, increased steeply during 2002–2007, peaking in 2008–2013 [IRR 1.63 (95% confidence interval 1.34–1.98)]. Transfer of disruptive knowledge on SBS/AHT during the period 2014–2019 was associated with a decline in maltreatment diagnoses [IRR 0.84 (95% confidence interval 0.71–0.99)].

Conclusion

An increase in maltreatment diagnoses was associated with transfer of supportive knowledge of the SBS/AHT paradigm, while a decline occurred toward the end of the study period, which might indicate a burgeoning de-implementation process.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13012-022-01188-6.

The Effect of 3D Whole, Major, and Small Vasculature On Mouse Brain Strain Under Both Diffuse and Focal Brain Injury Loading

Blood vessels are much stiffer than brain parenchyma and their effects in finite element (FE) brain models need to be investigated. Despite the publication of some comprehensive three-dimensional (3D) brain vasculature models, no mechanical model exists for the mouse brain vasculature. Moreover, how the vasculature affects the mechanical behavior of brain tissue remains controversial. Therefore, we developed FE mouse brain models with detailed 3D vasculature to investigate the effect of the vasculature on brain strains under both diffuse (closed-head impact) and focal injury (controlled cortical impact (CCI)) loading, two commonly laboratory models of traumatic brain injury. The effect of the vasculature was examined by comparing maximum principal strain in mouse brain FE models with and without the vasculature. On average, modeling comprehensive vasculature under diffuse injury loading reduced average brain strain predictions by 32% with non-linear elastic properties. Nearly three-fourths of the 32% strain reduction was attributable to the effects of the major branches of the vasculature. Meanwhile, during focal open-skull CCI injury loading, the contribution of the vasculature was limited, producing a less than 5% reduction in all cases. Overall, the vasculature, especially the major branches, increased the load-bearing capacity of the brain FE model and thus reduced brain strain predictions.

Neonatal Immune System Ontogeny: The Role of Maternal Microbiota and Associated Factors. How Might the Non-Human Primate Model Enlighten the Path?

Interactions between the immune system and the microbiome play a crucial role on the human health. These interactions start in the prenatal period and are critical for the maturation of the immune system in newborns and infants. Several factors influence the composition of the infant's microbiota and subsequently the development of the immune system. They include maternal infection, antibiotic treatment, environmental exposure, mode of delivery, breastfeeding, and food introduction. In this review, we focus on the ontogeny of the immune system and its association to microbial colonization from conception to food diversification. In this context, we give an overview of the mother-fetus interactions during pregnancy, the impact of the time of birth and the mode of delivery, the neonate gastrointestinal colonization and the role of breastfeeding, weaning, and food diversification. We further review the impact of the vaccination on the infant's microbiota and the reciprocal case. Finally, we discuss several potential therapeutic interventions that might help to improve the newborn and infant's health and their responses to vaccination. Throughout the review, we underline the main scientific questions that are left to be answered and how the non-human primate model could help enlighten the path.

Is mass screening for coeliac disease a wise use of resources? A health economic evaluation

Background

Living with undiagnosed symptomatic coeliac disease is connected with deteriorated health, and persons with coeliac disease often wait a long time for their diagnosis. A mass screening would lower the delay, but its cost-effectiveness is still unclear. Our aim was to determine the cost-effectiveness of a coeliac disease mass screening at 12 years of age, taking a life course perspective on future benefits and drawbacks.

Methods

The cost-effectiveness was derived as cost per quality-adjusted life-year (QALY) using a Markov model. As a basis for our assumptions, we mainly used information from the Exploring the Iceberg of Celiacs in Sweden (ETICS) study, a school-based screening conducted in 2005/2006 and 2009/2010, where 13,279 12-year-old children participated and 240 were diagnosed with coeliac disease, and a study involving members of the Swedish Coeliac Association with 1031 adult participants.

Results

The cost for coeliac disease screening was 40,105 Euro per gained QALY. Sensitivity analyses support screening based on high compliance to a gluten-free diet, rapid progression from symptom-free coeliac disease to coeliac disease with symptoms, long delay from celiac disease with symptoms to diagnosis, and a low QALY score for undiagnosed coeliac disease cases.

Conclusions

A coeliac disease mass screening is cost-effective based on the commonly used threshold of 50,000 Euro per gained QALY. However, this is based on many assumptions, especially regarding the natural history of coeliac disease and the effects on long-term health for individuals with coeliac disease still eating gluten.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01737-1.

Epidemiology, Presentation, and Diagnosis of Celiac Disease

The incidence of celiac disease is increasing, partly because of improved recognition of, and testing for, the disease. The rise in incidence is also due to a real increase of this immune-based disorder, independent of disease detection. The reasons for this true rise in recent decades are unknown but may be related to environmental factors that may promote loss of tolerance to dietary gluten. Strategies to reduce the development of celiac disease have not been proven successful in randomized trials, but the quantity of early-life gluten exposure has been a major focus of prevention efforts. The criteria for the diagnosis of celiac disease are changing, but in adults, diagnosis still depends on the presence of duodenal villous atrophy while the patient is on a gluten-containing diet, along with findings from serology analysis. Although guidelines in the United States continue to mandate a biopsy at all ages, some children receive a diagnosis of celiac disease without a biopsy. If proven accurate and scalable, assays that detect gluten-HLA tetramer complexes might be used in diagnosis to be made in the context of a gluten-free diet without intestinal biopsy.

Gut microbiota in Celiac Disease: microbes, metabolites, pathways and therapeutics

INTRODUCTION

Current evidence supports a vital role of the microbiota on health outcomes, with alterations in an otherwise healthy balance linked to chronic medical conditions like celiac disease (CD). Recent advances in microbiome analysis allow for unparalleled profiling of the microbes and metabolites. With the growing volume of data available, trends are emerging that support a role for the gut microbiota in CD pathogenesis.

AREAS COVERED

In this article, the authors review the relationship between factors such as genes and antibiotic exposure on CD onset and the intestinal microbiota. The authors also review other microbiota within the human body (like the oropharynx) that may play a role in CD pathogenesis. Finally, the authors discuss implications for disease modification and the ultimate goal of prevention. The authors reviewed literature from PubMed, EMBASE, and Web of Science.

EXPERT OPINION

CD serves as a unique opportunity to explore the role of the intestinal microbiota on the development of chronic autoimmune disease. While research to date provides a solid foundation, most studies have been case-control and thus do not have capacity to explore the mechanistic role of the microbiota in CD onset. Further longitudinal studies and integrated multi-omics are necessary for investigating CD pathogenesis.

The tight junction and the epithelial barrier in coeliac disease

Epithelial barriers are essential to maintain multicellular organisms well compartmentalized and protected from external environment. In the intestine, the epithelial layer orchestrates a dynamic balance between nutrient absorption and prevention of microorganisms, and antigen intrusion. Intestinal barrier function has been shown to be altered in coeliac disease but whether it contributes to the pathogenesis development or if it is merely a phenomenon secondary to the aberrant immune response is still unknown. The tight junction complexes are multiprotein cell-cell adhesions that seal the epithelial intercellular space and regulate the paracellular permeability of ions and solutes. These structures have a fundamental role in epithelial barrier integrity as well as in signaling mechanisms that control epithelial-cell polarization, the formation of apical domains and cellular processes such as cell proliferation, migration, differentiation, and survival. In coeliac disease, the molecular structures and function of tight junctions appear disrupted and are not completely recovered after treatment with gluten-free diet. Moreover, zonulin, the only known physiological regulator of the tight junction permeability, appears augmented in autoimmune conditions associated with TJ dysfunction, including coeliac disease. This chapter will examine recent discoveries about the molecular architecture of tight junctions and their functions. We will discuss how different factors contribute to tight junction disruption and intestinal barrier impairment in coeliac disease. To conclude, new insights into zonulin-driven disruption of tight junction structures and barrier integrity in coeliac disease are presented together with the advancements in novel therapy to treat the barrier defect seen in pathogenesis.

The Role of Early Programming and Early Nutrition on the Development and Progression of Celiac Disease: A Review

Experimental and epidemiological evidence has shown that modifications of the intrauterine environment can have deleterious consequences for individuals, expressed as an increased risk of suffering non-communicable pathologies in adult life, which is known as the hypothesis of the early origin of diseases or fetal programming. On the other hand, changes in gene expression patterns through epigenetic modifications can be the basis for long-term maintenance of the effects of fetal programming. In this sense, epigenetics comprises the study of intrauterine disturbances, which develop diseases in the adult, including celiac disease (CD). In addition, early feeding practices could influence the risk of CD development, such as breastfeeding timing and duration and age of gluten introduction in the diet. Gluten acts as a trigger for CD in genetically predisposed subjects, although approximately 30% of the world population has HLA DQ2 or DQ8, the prevalence of the disease is only 1–3%. It is not known what factors act to modify the risk of disease in genetically at-risk subjects. Taking into account all these considerations, the aim of the current review is to elucidate the role of early programming and the effect of early nutrition on the development and progression of CD. It is logical that attention has been paid to gluten as a key element in preventing the disease. However, there is no strong evidence in favor of the protective factor of breastfeeding, timing of introduction of gluten during lactation, and the development of CD. Diet, genetic risk, microbiota, and environmental interaction are possible triggers of the change in tolerance to an immune response to gluten, but large-scale cohort studies are needed. Emerging scientific concepts, such as epigenetics, may help us establish the role of these factors.

Early Gluten Introduction and Celiac Disease in the EAT Study: A Prespecified Analysis of the EAT Randomized Clinical Trial

IMPORTANCE

There are no strategies for the prevention of celiac disease (CD). Current guidelines stating that the age at gluten introduction does not affect the prevalence of CD are based on the results from several randomized clinical trials, but the doses of gluten and timing of its introduction varied.

OBJECTIVE

To determine whether early introduction of high-dose gluten lowers the prevalence of CD at age 3 years.

DESIGN, SETTING, AND PARTICIPANTS

The Enquiring About Tolerance (EAT) Study was an open-label randomized clinical trial. A total of 1303 children from the general population in England and Wales were recruited and followed up from November 2, 2009, to July 30, 2012. For the present study, samples were collected from November 1, 2012, to March 31, 2015, and data were analyzed from April 25, 2017, to September 17, 2018.

INTERVENTIONS

Infants were randomized to consume 6 allergenic foods (peanut, sesame, hen's egg, cow's milk, cod fish, and wheat) in addition to breast milk from age 4 months (early introduction group [EIG]) or to avoid allergenic foods and follow UK infant feeding recommendations of exclusive breastfeeding until approximately age 6 months (standard introduction group [SIG]).

MAIN OUTCOMES AND MEASURES

Evaluation of CD was an a priori secondary end point of the EAT Study, and at age 3 years, all children with available serum samples were tested for antitransglutaminase type 2 antibodies. Children with antibody levels greater than 20 IU/L were referred to independent gastroenterologists for further investigation.

RESULTS

Of the 1004 infants included in the analysis, 514 were male (51.2%). The mean (SD) quantity of gluten consumed between ages 4 and 6 months was 0.49 (1.40) g/wk in the SIG and 2.66 (1.85) g/wk in the EIG (P < .001). Mean (SD) weekly gluten consumption ranged from 0.08 (1.00) g/wk at age 4 months to 0.9 (2.05) g/wk at age 6 months in the SIG vs 1.3 (1.54) g/wk at age 4 months to 4.03 (2.40) g/wk at age 6 months in the EIG. Seven of 516 children from the SIG (1.4%) had a diagnosis of CD confirmed vs none of the 488 children in the EIG (P = .02, risk difference between the groups using the bootstrap, 1.4%; 95% CI, 0.6%-2.6%).

CONCLUSIONS AND RELEVANCE

In this analysis of infants in the EAT Study, the introduction of gluten from age 4 months was associated with reduced CD prevalence. These results suggest that early high-dose consumption of gluten should be considered as a strategy to prevent CD in future studies.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN14254740.

Celiac Disease in Kosovar Albanian Children: Evaluation of Clinical Features and Diagnosis

BACKGROUND

Celiac disease is an immune-mediated disorder characterized by variable clinical manifestations, specific antibodies, HLA-DQ2/DQ8 haplotypes, and enteropathy.

OBJECTIVES

The aim of this study was to present the clinical spectrum and patterns of celiac disease in Kosovar Albanian children.

METHODS

A cross-sectional retrospective study was performed with Albanian children aged 0-18 years, treated for celiac disease in the Pediatric Clinic, University Clinical Center of Kosovo from 2005 to 2016.

RESULTS

During the study period, 63 children were treated for celiac disease. The mean age at diagnosis was 5.5 years (SD ± 3.31). The mean age at celiac disease onset was 3.3 years (SD ± 2.02), while the mean delay from the first symptoms indicative of celiac disease to diagnosis was 2.2 years (SD ± 2.09). More than 70% of the patients were diagnosed in the first 7 years of life, mainly presented with gastrointestinal symptoms, while primary school children and adolescents mostly showed atypical symptoms (p<0.001). The classical form of celiac disease occurred in 78% of the cases. Sixty (95%) patients carried HLA-DQ2.5, DQ2.2 and/or HLA-DQ8 heterodimers, and only three of them tested negative.

CONCLUSION

Kosovo, as the majority of developing countries, is still facing the classical form of celiac disease as the dominant mode of presentation; as a result, most children with other forms of the celiac disease remain undiagnosed. Physicians should be aware of the wide range of clinical presentations and utilize low testing thresholds in order to prevent potential long-term problems associated with untreated celiac disease.

Dietary Gluten as a Conditioning Factor of the Gut Microbiota in Celiac Disease

The gut microbiota plays a relevant role in determining an individual's health status, and the diet is a major factor in modulating the composition and function of gut microbiota. Gluten constitutes an essential dietary component in Western societies and is the environmental trigger of celiac disease. The presence/absence of gluten in the diet can change the diversity and proportions of the microbial communities constituting the gut microbiota. There is an intimate relation between gluten metabolism and celiac disease pathophysiology and gut microbiota; their interrelation defines intestinal health and homeostasis. Environmental factors modify the intestinal microbiota and, in turn, its changes modulate the mucosal and immune responses. Current evidence from studies of young and adult patients with celiac disease increasingly supports that dysbiosis (i.e., compositional and functional alterations of the gut microbiome) is present in celiac disease, but to what extent this is a cause or consequence of the disease and whether the different intestinal diseases (celiac disease, ulcerative colitis, Crohn disease) have specific change patterns is not yet clear. The use of bacterial-origin enzymes that help completion of gluten digestion is of interest because of the potential application as coadjuvant in the current treatment of celiac disease. In this narrative review, we address the current knowledge on the complex interaction between gluten digestion and metabolism, celiac disease, and the intestinal microbiota.

Epidemiology of Celiac Disease

Celiac disease is a common, chronic inflammatory disorder of the small intestine triggered by exposure to gluten in individuals with certain genetic types. This disorder affects people of any age or gender. Although often thought to be European in origin, it is now global in extent. Presentations are variable, from asymptomatic patients to severe malnutrition. Initial detection usually relies on celiac-specific serology, and confirmation often requires intestinal biopsy. There have been substantial increases in prevalence and incidence over the last 2 decades for reasons that are almost certainly environmental but for which there is no clarity as to cause.

Coeliac disease

Coeliac disease is an immune-mediated enteropathy against dietary gluten present in wheat, rye and barley and is one of the most common lifelong food-related disorders worldwide. Coeliac disease is also considered to be a systemic disorder characterized by a variable combination of gluten-related signs and symptoms and disease-specific antibodies in addition to enteropathy. The ingestion of gluten leads to the generation of harmful gluten peptides, which, in predisposed individuals, can induce adaptive and innate immune responses. The clinical presentation is extremely variable; patients may have severe gastrointestinal symptoms and malabsorption, extraintestinal symptoms or have no symptoms at all. Owing to the multifaceted clinical presentation, diagnosis remains a challenge and coeliac disease is heavily underdiagnosed. The diagnosis of coeliac disease is achieved by combining coeliac disease serology and small intestinal mucosal histology during a gluten-containing diet. Currently, the only effective treatment for coeliac disease is a lifelong strict gluten-free diet; however, the diet is restrictive and gluten is difficult to avoid. Optimizing diagnosis and care in coeliac disease requires continuous research and education of both patients and health-care professionals.

Ten years of follow-up of the Spanish cohort of the European PreventCD study: the lessons learned

AIM

to evaluate the influence of gluten consumption on celiac disease development and to describe its natural history in the Spanish cohort of the European PreventCD study.

METHODS

prospective multi-center double blind study of 225 children that were followed up from birth. All cases were HLA-DQ2/HLA-DQ8 positive with a 1st degree relative with celiac disease and were followed up in three centers from Madrid, Reus and Valencia. Gluten intake was determined between four and ten months according to the protocol. Gluten intake was ad libitum between eleven and 36 months and was prospectively quantified by means of dietary records. Clinical visits and specific antibody analysis for celiac disease were performed periodically.

RESULTS

twenty-six cases were diagnosed, all had a positive biopsy and serology; 21 had gastrointestinal symptoms and five were asymptomatic. In addition, 2,565 food records were analyzed and statistically significant differences (p < 0.001) were found with regard to gluten consumption among the three centers, although not between celiac and non-celiac children (p = 0.025). The HLA-DQ2.5/DQ2.5 and DQ2.5/DQ2.2 genotypes had a relative risk of 4.7 (95% CI: 0.80-27.55; p = 0.08), which was higher than for the rest of genotypes. Female gender also had a relative risk that was five times higher than that for males.

CONCLUSIONS

the amount of gluten intake between 11 and 36 months or the duration of breast feeding were not risk factors for the development of CD in the Spanish population. The HLA genotype and gender were the most relevant associated factors. In this at-risk group, the disease presented before two years of age in the majority of the cases with a weak clinical expression.

The Relationship Between Child Mortality Rates and Prevalence of Celiac Disease

OBJECTIVES

Some evidence suggests that prevalence of celiac disease in the general population is increasing over time. Because the prognosis of celiac disease was a dismal one before discovering the role of gluten, our aim was to investigate a possible relationship between children under-5 mortality rates and prevalence rates of celiac disease.

METHODS

Thanks to a literature review, we found 27 studies performed in 17 different countries describing the prevalence of celiac disease in schoolchildren; between 1995 and 2011, 4 studies were performed in Italy. A meta-analysis of prevalence rates was performed. Prevalence was compared between specific country under-5 mortality groups, publication year, and age.

RESULTS

In the last decades, under-5 mortality rates have been decreasing all over the world. This reduction is paralleled by an increase of the prevalence of celiac disease. The Spearman correlation coefficient was -63%, 95% confidence interval -82% to -33% (P < 0.001). So, the higher the mortality rate, the lower the prevalence of CD. This finding is confirmed by the meta-analysis of the 4 studies conducted in Italy over time.

CONCLUSIONS

The under-5 mortality rate seems to influence the prevalence of celiac disease in the general population. In the near future, the number of patients with celiac disease will increase, thanks to the better environmental conditions that nowadays allow a better survival of children with celiac disease.

Coeliac disease

Coeliac disease occurs in about 1% of people in most populations. Diagnosis rates are increasing, and this seems to be due to a true rise in incidence rather than increased awareness and detection. Coeliac disease develops in genetically susceptible individuals who, in response to unknown environmental factors, develop an immune response that is subsequently triggered by the ingestion of gluten. The disease has many clinical manifestations, ranging from severe malabsorption to minimally symptomatic or non-symptomatic presentations. Diagnosis requires the presence of duodenal villous atrophy, and most patients have circulating antibodies against tissue transglutaminase; in children, European guidelines allow a diagnosis without a duodenal biopsy provided that strict symptomatic and serological criteria are met. Although a gluten-free diet is an effective treatment in most individuals, a substantial minority develop persistent or recurrent symptoms. Difficulties adhering to a gluten-free diet have led to the development of non-dietary therapies, several of which are undergoing trials in human beings.

Celiac Disease Prevention

Celiac disease (CD) is a common autoimmune disorder induced by ingestion of gluten in genetically susceptible individuals. Despite the prerequisite for a genetic predisposition, only a minority of the 40% of the Caucasian population that has this genetic predisposition develops the disease. Thus, environmental and/or lifestyle factors play a causal role in the development of CD. The incidence of CD has increased over the last half-century, resulting in rising interest in identifying risk factors for CD to enable primary prevention. Early infant feeding practices have been suggested as one of the factors influencing the risk of CD in genetically susceptible individuals. However, recent large prospective studies have shown that neither the timing of gluten introduction nor the duration or maintenance of breastfeeding influence the risk of CD. Also, other environmental influences have been investigated as potential risk factors, but have not led to primary prevention strategies. Secondary prevention is possible through early diagnosis and treatment. Since CD is significantly underdiagnosed and a large proportion of CD patients are asymptomatic at the time of diagnosis, secondary prevention will not identify all CD patients, as long as mass screening has not been introduced. As following a gluten-free diet is a major challenge, tertiary prevention strategies are discussed as well.

Celiac Disease: A Review of Current Concepts in Pathogenesis, Prevention, and Novel Therapies

Our understanding of celiac disease and how it develops has evolved significantly over the last half century. Although traditionally viewed as a pediatric illness characterized by malabsorption, it is now better seen as an immune illness with systemic manifestations affecting all ages. Population studies reveal this global disease is common and, in many countries, increasing in prevalence. These studies underscore the importance of specific HLA susceptibility genes and gluten consumption in disease development and suggest that other genetic and environmental factors could also play a role. The emerging data on viral and bacterial microbe-host interactions and their alterations in celiac disease provides a plausible mechanism linking environmental risk and disease development. Although the inflammatory lesion of celiac disease is complex, the strong HLA association highlights a central role for pathogenic T cells responding to select gluten peptides that have now been defined for the most common genetic form of celiac disease. What remains less understood is how loss of tolerance to gluten occurs. New insights into celiac disease are now providing opportunities to intervene in its development, course, diagnosis, and treatment.

Gut microbiome: a new player in gastrointestinal disease

The gastrointestinal (GI) tract harbors a diverse and host-specific gut microbial community. Whereas host-microbe interactions are based on homeostasis and mutualism, the microbiome also contributes to disease development. In this review, we summarize recent findings connecting the GI microbiome with GI disease. Starting with a description of biochemical factors shaping microbial compositions in each gut segment along the longitudinal axis, improved histological techniques enabling high resolution visualization of the spatial microbiome structure are highlighted. Subsequently, inflammatory and neoplastic diseases of the esophagus, stomach, and small and large intestines are discussed and the respective changes in microbiome compositions summarized. Finally, approaches aiming to restore disturbed microbiome compositions thereby promoting health are discussed.

Intestinal epithelium, intraepithelial lymphocytes and the gut microbiota - Key players in the pathogenesis of celiac disease

Celiac disease (CD) is a chronic immune-mediated disorder triggered by the ingestion of gluten in genetically predisposed individuals. Before activating the immune system, gluten peptides are transferred by the epithelial barrier to the mucosal lamina propria, where they are deamidated by intestinal tissue transglutaminase 2. As a result, they strongly bind to human leucocyte antigens (HLAs), especially HLA-DQ2 and HLA-DQ8, expressed on antigen-presenting cells. This induces an inflammatory response, which results in small bowel enteropathy. Although gluten is the main external trigger activating both innate and adaptive (specific) immunity, its presence in the intestinal lumen does not fully explain CD pathogenesis. It has been hypothesized that an early disruption of the gut barrier in genetically susceptible individuals, which would result in an increased intestinal permeability, could precede the onset of gluten-induced immune events. The intestinal barrier is a complex functional structure, whose functioning is dependent on intestinal microbiota homeostasis, epithelial layer integrity, and the gut-associated lymphoid tissue with its intraepithelial lymphocytes (IELs). The aim of this paper was to review the current literature and summarize the role of the gut microbiota, epithelial cells and their intercellular junctions, and IELs in CD development.

Immunopathology of childhood celiac disease-Key role of intestinal epithelial cells

BACKGROUND & AIMS

Celiac disease is a chronic inflammatory disease of the small intestine mucosa due to permanent intolerance to dietary gluten. The aim was to elucidate the role of small intestinal epithelial cells in the immunopathology of celiac disease in particular the influence of celiac disease-associated bacteria.

METHODS

Duodenal biopsies were collected from children with active celiac disease, treated celiac disease, and clinical controls. Intestinal epithelial cells were purified and analyzed for gene expression changes at the mRNA and protein levels. Two in vitro models for human intestinal epithelium, small intestinal enteroids and polarized tight monolayers, were utilized to assess how interferon-γ, interleukin-17A, celiac disease-associated bacteria and gluten influence intestinal epithelial cells.

RESULTS

More than 25 defense-related genes, including IRF1, SPINK4, ITLN1, OAS2, CIITA, HLA-DMB, HLA-DOB, PSMB9, TAP1, BTN3A1, and CX3CL1, were significantly upregulated in intestinal epithelial cells at active celiac disease. Of these genes, 70% were upregulated by interferon-γ via the IRF1 pathway. Most interestingly, IRF1 was also upregulated by celiac disease-associated bacteria. The NLRP6/8 inflammasome yielding CASP1 and biologically active interleukin-18, which induces interferon-γ in intraepithelial lymphocytes, was expressed in intestinal epithelial cells.

CONCLUSION

A key factor in the epithelial reaction in celiac disease appears to be over-expression of IRF1 that could be inherent and/or due to presence of undesirable microbes that act directly on IRF1. Dual activation of IRF1 and IRF1-regulated genes, both directly and via the interleukin-18 dependent inflammasome would drastically enhance the inflammatory response and lead to the pathological situation seen in active celiac disease.

Microbial Transglutaminase Used in Bread Preparation at Standard Bakery Concentrations Does Not Increase Immunodetectable Amounts of Deamidated Gliadin

The effect of standard bakery concentrations of microbial transglutaminase (MTG) in wheat bread preparation on the immunoreactivity of sera of celiac disease (CD) patients was investigated. Immunoblotting using monoclonal antibodies specific to unmodified and/or deamidated gliadin showed no differences between control bread and MTG bread. Deamidation of gliadin could not be detected at standard MTG concentrations. Sera of CD patients were characterized using anti-gliadin and anti-deamidated gliadin peptide (DGP) enzyme-linked immunosorbent assay and grouped into DGP high- and low-titer pools. The recognition pattern obtained after using both CD sera pools for immunoblotting did not reveal differences between control and MTG-treated bread protein extracts. Our results indicate that MTG treatment of wheat bread prepared with typical MTG concentrations used in standard bakery processes does not lead to immunodetectable amounts of CD immunotoxic deamidated gliadins.

Comparative proteomic analysis of two transgenic low-gliadin wheat lines and non-transgenic wheat control

Gluten proteins are major determinants of the bread making quality of wheat, but also of important wheat-related disorders, including coeliac disease (CD), and allergies. We carried out a proteomic study using the total grain proteins from two low-gliadin wheat lines, obtained by RNAi, and the untransformed wild type as reference. The impact of silencing on both target and on non-target proteins was evaluated. Because of the great protein complexity, we performed separate analyses of four kernel protein fractions: gliadins and glutenin subunits, and metabolic and CM-like proteins, by using a classical 2D electrophoresis gel based approach followed by RP-HPLC/nESI-MS/MS. As a result of the strong down-regulation of gliadins, the HMW-GS, metabolic and chloroform/methanol soluble proteins were over-accumulated in the transgenic lines, especially in the line D793, which showed the highest silencing of gliadins. Basing on these data, and considering that metabolic proteins and chloroform/methanol soluble proteins (CM-like), such as the α-amylase/trypsin inhibitor family, β-amylase and serpins, were related to wheat allergens, further in vivo analysis will be needed, especially those related to clinical trials in controlled patients, to determine if these lines could be used for food preparation for celiac or other gluten intolerant groups.

BIOLOGICAL SIGNIFICANCE

Several enteropathies and allergies are related to wheat proteins. Biotechnological techniques such as genetic transformation and RNA interference have allowed the silencing of gliadin genes, providing lines with very low gliadin content in the grains. We report a proteomic-based approach to characterize two low-gliadin transgenic wheat lines obtained by RNAi technology. These lines harbor the same silencing fragment, but driven by two different endosperm specific promoters (γ-gliadin and D-hordein). The comprehensive proteome analysis of these transgenic lines, by combining two-dimensional electrophoresis and RP-HPLC/nESI-MS/MS, provided a large number of spots differentially expressed between the control and the transgenic lines. Hence, the results of this study will facilitate further safety evaluation of these transgenic lines.

High Incidence of Celiac Disease in a Long-term Study of Adolescents With Susceptibility Genotypes

BACKGROUND & AIMS

Little is known about the incidence of celiac disease in the general population of children in the United States. We aimed to estimate the cumulative incidence of celiac disease in adolescents born in the Denver metropolitan area.

METHODS

We collected data on HLA-DR, DQ genotypes of 31,766 infants, born from 1993 through 2004 at St. Joseph's Hospital in Denver, from the Diabetes Autoimmunity Study in the Young. Subjects with susceptibility genotypes for celiac disease and type 1 diabetes were followed up for up to 20 years for development of tissue transglutaminase autoantibodies (tTGA). Outcomes were the development of celiac disease autoimmunity (CDA) or celiac disease. CDA was defined as persistence of tTGA for at least 3 months or development of celiac disease. Celiac disease was defined based on detection of Marsh 2 or greater lesions in biopsy specimens or persistent high levels of tTGA. For each genotype, the cumulative incidence of CDA and celiac disease were determined. To estimate the cumulative incidence in the Denver general population, outcomes by each genotype were weighted according to the frequency of each of these genotypes in the general population.

RESULTS

Of 1339 subjects followed up, 66 developed CDA and met criteria for celiac disease and 46 developed only CDA. Seropositivity for tTGA resolved spontaneously, without treatment, in 21 of the 46 subjects with only CDA (46%). The estimated cumulative incidence for CDA in the Denver general population at 5, 10, and 15 years of age was 2.4%, 4.3%, and 5.1%, respectively, and incidence values for celiac disease were 1.6%, 2.8%, and 3.1%, respectively.

CONCLUSIONS

In a 20-year prospective study of 1339 children with genetic risk factors for celiac disease, we found the cumulative incidence of CDA and celiac disease to be high within the first 10 years. Although more than 5% of children may experience a period of CDA, not all children develop celiac disease or require gluten-free diets.

The role of gluten consumption at an early age in celiac disease development: a further analysis of the prospective PreventCD cohort study

Background: We previously found that the introduction of small quantities of gluten at 4-6 mo of age did not reduce the risk of celiac disease (CD) in a group of high-risk children. However, the consumption of high amounts of gluten early in life has been suggested to increase CD risk.Objective: The aim of this study was to evaluate this hypothesis by using data from the previous study of the PreventCD trial (www.preventcd.com).Design: Gluten intake was prospectively quantified by using specific food records between 11 and 36 mo of age in 715 children positive for the human leukocyte antigen (HLA)-DQ2 and/or HLA-DQ8 from 5 European countries. According to the PreventCD protocol, infants received 100 mg immunologically active gluten/d or placebo from 4 to 6 mo of age, with a stepwise and fixed gluten increase until age 10 mo and unrestricted intake thereafter. The primary outcome of the present study was the impact of the amount of gluten consumed from age 10 mo onward on CD development.Results: Mean daily gluten intakes from 10 mo onward were significantly different between countries for children at all ages (P < 0.001) but not between children who developed CD and those who did not within the same country (P > 0.05). The variables country, sex, intervention group, and gluten consumption pattern did not show significant associations with CD development risk (HRs not significant). In addition, the interaction between HLA risk group and gluten consumption pattern showed no significant risk on CD development, except for the DQ2.2/DQ7 haplotype (HR: 5.81; 95% CI: 1.18, 28.74; P = 0.031).Conclusions: Gluten consumption patterns as well as the amount of gluten consumed at 11-36 mo of age do not influence CD development for most related HLA genotypes in children with a genetic risk. This study reports the gluten consumption pattern in children at risk of CD from different European countries. This trial was registered at www.controlled-trials.com as ISRCTN74582487.

Symptoms and Mucosal Changes Stable During Rapid Increase of Pediatric Celiac Disease in Norway

OBJECTIVES

We aimed to study whether the incidence of pediatric celiac disease (CD) in South-Eastern Norway changed from 2000 to 2010. We also examined whether there was a change in symptoms and histopathological morphology in the duodenal biopsies during the same period.

METHODS

In 3 hospitals in South-Eastern Norway, records from pediatric patients (0-14.9 years) diagnosed with CD during two 3-year periods (2000-2002 and 2008-2010) were reviewed. Only cases with a duodenal biopsy diagnosis of CD classified as Marsh grade 2 and 3a-c were included. Frequencies of symptoms, anthropometric data, and laboratory results were compared, in addition to re-examinations of histological sections from one of the hospitals.

RESULTS

A total of 400 cases were diagnosed with a female to male ratio of 1.5:1. The incidence rate for 2000 to 2002 was 15.9 cases per 100,000 person-years (95% confidence interval 12.8-19.4), compared with 45.5 cases per 100,000 person-years during 2008 to 2010 (95% confidence interval 40.5-50.9), P < 0.001. The relative frequencies of symptoms and the distribution of histopathological changes were similar in the 2 periods, whereas weight z scores and hemoglobin levels were significantly lower in the first period.

CONCLUSIONS

We found a 3-fold increase in the incidence rate for CD in the Norwegian pediatric population during the decade 2000 to 2010. Slightly higher weight and hemoglobin levels at diagnosis in the latter period may be due to improved CD awareness. Unaltered relative frequencies of symptoms and histopathological changes in the gut, however, suggest a true increase of CD in Norwegian children.

Celiac Disease: Role of the Epithelial Barrier

In celiac disease (CD) a T-cell-mediated response to gluten is mounted in genetically predisposed individuals, resulting in a malabsorptive enteropathy histologically highlighted by villous atrophy and crypt hyperplasia. Recent data point to the epithelial layer as an under-rated hot spot in celiac pathophysiology to date. This overview summarizes current functional and genetic evidence on the role of the epithelial barrier in CD, consisting of the cell membranes and the apical junctional complex comprising sealing as well as ion and water channel-forming tight junction proteins and the adherens junction. Moreover, the underlying mechanisms are discussed, including apoptosis of intestinal epithelial cells, biology of intestinal stem cells, alterations in the apical junctional complex, transcytotic uptake of gluten peptides, and possible implications of a defective epithelial polarity. Current research is directed toward new treatment options for CD that are alternatives or complementary therapeutics to a gluten-free diet. Thus, strategies to target an altered epithelial barrier therapeutically also are discussed.

Introduction of complementary foods in Sweden and impact of maternal education on feeding practices

OBJECTIVE

To describe the introduction of complementary foods in a population-based cohort in relation to recommendations and explore the possible impact of maternal education on infant feeding practices.

DESIGN

Prospective data from the All Babies in Southeast Sweden (ABIS) cohort study were used. The ABIS study invited all infants born in south-east Sweden during October 1997-October 1999 (n 21 700) to participate. A questionnaire was completed for 16 022 infants. During the infants' first year parents continuously filed in a diary covering introduction of foods.

SETTING

Sweden.

SUBJECTS

Infants (n 9727) with completed food diaries.

RESULTS

Potatoes, vegetables, fruits/berries and porridge were the foods first introduced, with a median introduction between 19 and 22 weeks, followed by introduction of meat, cow's milk, follow-on formula and sour milk/yoghurt between 24 and 27 weeks. Early introduction of any food, before 16 weeks, occurred for 27 % of the infants and was more common in infants of mothers with low education. Overall, potatoes (14·7 %), vegetables (11·1 %), fruits/berries (8·5 %), porridge (7·4 %) and follow-on formula (2·7 %) were the foods most frequently introduced early. The majority of infants (≥70 %) were introduced to potatoes, vegetables, fruits/berries and porridge during concurrent breast-feeding, but introduction during concurrent breast-feeding was less common in infants of mothers with low education.

CONCLUSIONS

Most infants were introduced to complementary foods timely in relation to recommendations. Low maternal education was associated with earlier introduction of complementary foods and less introduction during concurrent breast-feeding. Still, the results indicated exposure to fewer foods at 12 months in infants of mothers with low education.

Peptides from gluten digestion: A comparison between old and modern wheat varieties

Coeliac disease is an autoimmune enteropathy that develops in genetically predisposed subjects after the ingestion of gluten or related proteins. Coeliac disease has an increasing incidence in the last years in western countries and it has been suggested that wheat breeding might have contributed to select more toxic forms of gluten. In this work, we analysed gluten peptides generated by in vitro digestion of different old and modern Triticum varieties, using LC-MS. We concluded that old varieties analysed produced a higher quantity of peptides containing immunogenic and toxic sequences than modern ones. Thus old wheat lines are not to be considered "safer" for subjects that are genetically predisposed to celiac disease.

Season and region of birth as risk factors for coeliac disease a key to the aetiology?

BACKGROUND

Coeliac disease (CD) incidence has increased in recent decades, characterised by variations according to sex, age at diagnosis, year of birth, month of birth and region of birth. Genetic susceptibility and exposure to gluten are the necessary factors in CD aetiology, although several environmental factors are considered.

METHODS

A nationwide prospective cohort longitudinal study was conducted consisting of 1 912 204 children aged 0-14.9 years born in Sweden from 1991 to 2009. A total of 6569 children were diagnosed with biopsy-verified CD from 47 paediatric departments. Using Cox regression, we examined the association between CD diagnosis and season of birth, region of birth and year of birth.

RESULTS

Overall, CD risk was higher for children born during spring, summer and autumn as compared with children born during winter: adjusted HR for spring 1.08 (95% CI 1.01 to 1.16), summer 1.10 (95% CI 1.03 to 1.18) and autumn 1.10 (95% CI 1.02 to 1.18). Increased CD risk was highest if born in the south, followed by central Sweden when compared with children born in northern Sweden. Children diagnosed at <2 years had an increased CD risk if born in spring while those diagnosed at 2-14.9 years the risk was increased for summer and autumn births. The birth cohort of 1991-1996 had increased CD risk if born during spring, for the 1997-2002 birth cohort the risk increased for summer and autumn births, while for the birth cohort of 2003-2009 the risk was increased if born during autumn.

CONCLUSIONS

Season of birth and region of birth are independently and jointly associated with increased risk of developing CD during the first 15 years of life. Seasonal variation in infectious load is the likely explanation.

Heritability of non-HLA genetics in coeliac disease: a population-based study in 107 000 twins

BACKGROUND AND OBJECTIVE

Almost 100% individuals with coeliac disease (CD) are carriers of the human leucocyte antigen (HLA) DQ2/DQ8 alleles. Earlier studies have, however, failed to consider the HLA system when estimating heritability in CD, thus violating an underlying assumption of heritability analysis. We examined the heritability of CD in a large population-based sample of twins, considering HLA.

DESIGN

In a population-representative sample of 107 912 twins, we identified individuals with CD (equal to villous atrophy) through biopsy reports from all Swedish pathology departments. We calculated concordance rates and tetrachoric correlations for monozygotic (MZ) and dizygotic (DZ) twin pairs. Further, we estimated heritability of CD, first strictly from observed data, and then the non-HLA heritability, representing the heritability of all genetic factors except the HLA locus, using an approach that circumvent the violation of underlying assumptions.

RESULTS

We identified 513 twins with a diagnosis of CD (prevalence 0.48%). Concordance rates were higher in MZ pairs (0.49) than in DZ pairs (0.10), as were tetrachoric correlations (0.89 in MZ vs 0.51 in DZ pairs). The heritability of CD was 75% (95% CI 55% to 96%). The non-HLA heritability was slightly attenuated, 68% (95% CI 40% to 96%), with shared (17%) and non-shared (15%) environmental factors explaining the remaining variability of CD.

CONCLUSIONS

CD is characterised by a high heritability, but our study also suggests that non-shared environmental factors may be of importance to CD development. HLA seems to have only moderate impact on heritability estimates.

Dietary Gluten-Induced Gut Dysbiosis Is Accompanied by Selective Upregulation of microRNAs with Intestinal Tight Junction and Bacteria-Binding Motifs in Rhesus Macaque Model of Celiac Disease

The composition of the gut microbiome reflects the overall health status of the host. In this study, stool samples representing the gut microbiomes from 6 gluten-sensitive (GS) captive juvenile rhesus macaques were compared with those from 6 healthy, age- and diet-matched peers. A total of 48 samples representing both groups were studied using V4 16S rRNA gene DNA analysis. Samples from GS macaques were further characterized based on type of diet administered: conventional monkey chow, i.e., wheat gluten-containing diet (GD), gluten-free diet (GFD), barley gluten-derived diet (BOMI) and reduced gluten barley-derived diet (RGB). It was hypothesized that the GD diet would lower the gut microbial diversity in GS macaques. This is the first report illustrating the reduction of gut microbial alpha-diversity (p < 0.05) following the consumption of dietary gluten in GS macaques. Selected bacterial families (e.g., Streptococcaceae and Lactobacillaceae) were enriched in GS macaques while Coriobacteriaceae was enriched in healthy animals. Within several weeks after the replacement of the GD by the GFD diet, the composition (beta-diversity) of gut microbiome in GS macaques started to change (p = 0.011) towards that of a normal macaque. Significance for alpha-diversity however, was not reached by the day 70 when the feeding experiment ended. Several inflammation-associated microRNAs (miR-203, -204, -23a, -23b and -29b) were upregulated (p < 0.05) in jejunum of 4 biopsied GS macaques fed GD with predicted binding sites on 16S ribosomal RNA of Lactobacillus reuteri (accession number: NR_025911), Prevotella stercorea (NR_041364) and Streptococcus luteciae (AJ297218) that were overrepresented in feces. Additionally, claudin-1, a validated tight junction protein target of miR-29b was significantly downregulated in jejunal epithelium of GS macaques. Taken together, we predict that with the introduction of effective treatments in future studies the diversity of gut microbiomes in GS macaques will approach those of healthy individuals. Further studies are needed to elucidate the regulatory pathways of inflammatory miRNAs in intestinal mucosa of GS macaques and to correlate their expression with gut dysbiosis.

Scientific evidence and daily food for a better life: Milan, 19 June 2015

This paper presents a report of a nutrition conference held at EXPO 2015 in Milan. Over the course of a day, seven speakers from four continents discussed the evidence and scientific processes that underpin the development of dietary guidelines, highlighting issues and challenges at each stage. These include the quality of studies associating disease outcomes with diet, specifically a reliance on observational studies, short duration of intervention trials, low statistical power and lack of follow-up. Concerns were raised over the oversimplification of dietary messages which promote carbohydrates in general without evidence of benefit, while restricting fats when meta-analyses suggests that different fatty acids have different effects on disease risk. The merits of food-based dietary guidelines and holistic dietary patterns were described, whereas the impact of increasing or reducing consumption of individual food groups or macronutrients remains unclear. The meeting ended with a restatement of the importance of dietary guidelines, and associated education, to improve public health, but a plea was made to ensure that the process of setting guidelines is evidence based, responsive and considers the impact of the whole diet.