A prospective, double-blind, placebo-controlled trial to establish a safe gluten threshold for patients with celiac disease

The effect of self-efficacy expectations in the adherence to a gluten free diet in celiac disease

Objective: To analyse the effect of general and specific self-efficacy on the adherence to a gluten free diet (GFD) in patients with celiac disease along with the effect of other relevant variables.Design: 271 patients with celiac disease participated in this transversal descriptive study and completed a series of questionnaires regarding adherence (CDAT), general self-efficacy (GSES) and specific self-efficacy (Celiac-SE) and quality of life (CD-Qol), among others.Main Outcome Measures: Dependent variable was adherence to the Gluten Free Diet (GFD). Main independent variables were general self-efficacy, specific self-efficacy and quality of life. Model tests were conducted using regression analysis.Results: 71.9% of patients show an excellent or good adherence to the diet. Higher levels of adherence are positively associated to a high expectancy of specific self-efficacy, to the perceived adoption of recommended behaviours, risk perception and better quality of life (these variables accounted for 36.4% of the variance in the adherence to a GFD, p < .001).Conclusions: Specific self-efficacy rather than general has a predictive value in adherence to a GFD. Therefore, we need to develop and transculturally adapt new instruments to assess specific self-efficacy. Celiac-SE has proved to be a useful scale for this objective.

Toward New Paradigms in the Follow Up of Adult Patients With Celiac Disease on a Gluten-Free Diet

Gluten free diet is the only available treatment for celiac disease (CeD). Patients with CeD who do not adhere to a strict gluten-free diet (GFD) have been found to have complications involving nutritional deficiencies, increased risk of bone fractures, increased risk of mortality, and certain types of cancers. Complete removal of gluten from the diet in a patient with CeD often results in symptomatic, serologic, and histologic remission. However, strict compliance with the diet is challenging. Long-term follow-up care is needed to assure treatment compliance and positive health outcomes. Monitoring celiac specific serology, nutrient deficiencies, bone mineral density, and assessment of GFD compliance have been recommended in clinical practice. However, there is no consensus on which specific tests and how often they should be performed during the follow up. Here, we have performed a review of the literature on current strategies to follow up patients with CeD. There are new tools for monitoring adherence to the GFD which could change some paradigms in following up treated patients.

The 5 Ws of a gluten challenge for gluten-related disorders

Gluten-related disorders (GRDs) are gradually emerging as epidemiologically relevant diseases, with a global prevalence estimated to be approximately 5% in the population. Conditions related to gluten ingestion include celiac disease (CD), wheat allergy (WA), and nonceliac gluten sensitivity (NCGS). Although mediated by different pathogenic pathways, these 3 conditions share similar clinical manifestations and can present a difficult differential diagnosis. The gluten challenge (GC) is an important diagnostic tool for GRDs, but there is great variability in regards to deciding which patients should be challenged, what amount of gluten should be used, what the GC duration should be, when and where the GC should occur, and, sometimes, why to conduct a GC. This review summarizes the current knowledge about the desirable characteristics of GCs in the 3 main GRDs following a 5 Ws approach-that is, the 5 main journalistic questions: who, what, when, where, why. The answers will help to determine the correct use of the GC in diagnosing GRDs.

Gluten and FODMAPS-Sense of a Restriction/When Is Restriction Necessary?

Gluten-free diet (GFD) is enjoying increasingly popularity, although gluten-free products are considerably more expensive. GFD is absolutely necessary for patients with celiac disease, as in this case even minor amounts of gluten can lead to the destruction of the intestinal mucosa. In addition, GFD is currently the best therapy to improve clinical symptoms of patients with non-celiac gluten sensitivity (NCGS), although the diet may not be as strict as that for patients with celiac disease. Beside gluten, other wheat components such as oligosaccharides and amylase trypsin inhibitors are discussed as triggers of NCGS in this review. An overlap between gastrointestinal symptoms in NCGS and irritable bowel syndrome (IBS) is described. Patients with NCGS attribute their symptoms to the consumption of gluten, while patients with IBS rarely describe gluten as a trigger. Recently, several studies have demonstrated that the introduction of a low FODMAP (fermentable oligo-, di-, monosaccharides, and polyols) diet reduced gastrointestinal symptoms in patients with IBS and this diet is suggested as the first choice of therapy in IBS. However, a low FODMAP diet also eliminates prebiotica and may negatively influence the gut microbiota. For this reason, the diet should be liberalized after symptom improvement. There is no evidence that a GFD is healthier than the standard diet. In contrast, GFD often is accompanied by nutritional deficiencies, mainly minerals and vitamins. Therefore, GFD and low FODMAP diets are not recommended for healthy subjects. Since wheat contains fructans belonging to FODMAPs), a GFD is not only gluten-free but also has less FODMAPs. Thus, symptom improvement cannot be correctly correlated with the reduction of either one or the other.

Prospective longitudinal study: use of faecal gluten immunogenic peptides to monitor children diagnosed with coeliac disease during transition to a gluten-free diet

BACKGROUND

Treatment for coeliac disease is a lifelong strict gluten-free diet. Although guidelines recommend regular follow-up with dietary interviews and coeliac serology, these methods may be inaccurate.

AIM

To evaluate the usefulness of faecal gluten immunogenic peptides to support the diagnosis and to determine the adherence to the gluten-free diet in coeliac children.

METHODS

Multicentre prospective observational study including 64 coeliac children. Faecal gluten peptides, and tissue transglutaminase and deamidated gliadin peptide antibodies were analyzed at diagnosis, and 6, 12 and 24 months thereafter. Gluten consumption was estimated from gluten peptide levels.

RESULTS

Most children (97%) had detectable gluten peptides at diagnosis. On a gluten-free diet, the rate of gluten peptides increased from 13% at 6 months to 25% at 24 months. Mean estimated gluten exposure dropped from 5543 mg/d at diagnosis to 144 mg/d at 6 months, then increased to 606 mg/d by 24 months. In contrast, deamidated gliadin peptide antibodies normalised and only 20% had elevated tissue transglutaminase antibody by 24 months. The elevation of tissue transglutaminase antibody was more prolonged in patients with detectable gluten peptides (P < 0.05). Nevertheless, absolute levels of tissue transglutaminase antibody had low sensitivity to identify patients with detectable gluten peptides (P > 0.1). Dietitian assessment was only moderately correlated with gluten peptide detection (κ = 0.5).

CONCLUSIONS

Faecal gluten peptides testing may guide treatment of coeliac disease prior to diagnosis and during the assessment diet adherence. Further studies could determine if early identification of gluten exposure reduces the need for expensive/invasive investigations for non-responsive coeliac disease. ClinicalTrials.gov Number: NCT02711397.

Detection of Gluten in Gluten-Free Labeled Restaurant Food: Analysis of Crowd-Sourced Data

INTRODUCTION

Adherence to a gluten-free (GF) diet is the mainstay of therapy for celiac disease. Until now, those wishing to avoid gluten in restaurants had to rely on menu labels, word of mouth, intuition, and restaurant workers' advice, with a relative dearth of supporting data. We used crowd-sourced data from users of a portable gluten detection device to estimate rates of, and identify risk factors for, gluten contamination of supposed GF restaurant foods.

METHODS

We analyzed data from a portable gluten detection device (Nima), collected across the United States during an 18-month period by users who opted to share the results of their point-of-care tests. Data were sorted by region, time of day, median household income in the restaurant's vicinity, restaurant genre, and food items. We used the χ test for bivariate analysis and multiple logistic regression for multivariate analysis to identify predictors of gluten detection in restaurant food.

RESULTS

There were 5,624 tests, performed by 804 users, in the examined period. Gluten was detected in 32% of GF labeled foods. Rates of gluten detection differed by meal, with 27.2% at breakfast and 34.0% at dinner (P = 0.0008). GF labeled pizza and pasta were most likely to test positive for gluten, with gluten detected in 53.2% of pizza and 50.8% of pasta samples. On multivariate analysis, GF labeled food was less likely to test positive for gluten in the West than in the Northeast United States (odds ratio 0.80; 95% confidence interval 0.67-0.95).

CONCLUSIONS

This study of crowd-sourced data suggests that a substantial fraction of GF labeled restaurant foods contain detectable gluten. Although the highly sensitive Nima device may detect gluten at levels <20 parts per million (ppm), leading to gluten exposure of unknown clinical significance, our findings raise a potential concern. In addition, our findings of higher rates of gluten detection in pizza and pasta provide practical data when providing dining strategies for patients with celiac disease.

Inadvertent and minimal gluten intake has a negligible role in the onset of symptoms in patients with coeliac disease on a gluten-free diet

Although the quantity of gluten that a well-instructed coeliac patient can involuntarily ingest is <10 mg of gluten/d which cannot induce significant villous damage, coeliac patients often attribute the origin of symptoms to the involuntary ingestion of trace quantities of gluten, either certain or hypothetical. Our aim was to evaluate whether the occurrence of symptoms in coeliac patients who histologically responded to a strict gluten-free diet was related to the involuntary consumption of minimal quantities of gluten. A case–control study to assess the association between gluten exposure and the occurrence of symptoms was designed. Between January 2017 and May 2018, coeliac patients attending our outpatient clinic were interviewed to detect the presence of symptoms. Based on a specifically designed form, patients were also divided into different risk groups of gluten exposure. A total of ninety-five coeliac patients on a strict gluten-free diet and with known histological recovery were enroled. Of them, fifty-two of them reported symptoms and they were enroled as cases; the remaining forty-three patients denied symptoms and were enroled as controls. Although this was not statistically significant, gluten exposure was more frequent in controls (Fisher’s exact test, P=0·07). Our results show no relationship between exposure to minimal quantities of gluten and onset of symptoms in coeliac patients. Symptoms are more frequent in patients who have no risk of gluten exposure. It is possible that the presence of these symptoms leads the patients to avoid situations that may place them at risk of gluten exposure.

Gluten in Celiac Disease-More or Less?

To date, the only known effective treatment for celiac disease is a strict gluten-free diet for life. We reviewed the literature to evaluate the upper limit for gluten content in food, which would be safe for patients with celiac disease. Patients with celiac disease should limit their daily gluten intake to no more than 10-50 mg. Most health authorities define gluten-free products as containing less than 20 parts per million gluten.

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.

Contribution of Oral Hygiene and Cosmetics on Contamination of Gluten-free Diet: Do Celiac Customers Need to Worry About?

OBJECTIVES

The only available treatment for celiac disease (CD) is the gluten-free diet. It is unclear whether the presence of gluten in oral hygiene products and cosmetics that are applied on the mouth is a reason of concern for CD patients. The aim of this study was to test the level of gluten contamination in oral hygiene and cosmetic products available in the Italian market.

METHODS

A total of 66 products (toothpastes = 37; dental tablets = 2; mouthwashes = 5; lip-balms = 10; lipsticks = 12) labelled gluten-free or with unknown gluten content were randomly collected from different supermarkets and pharmacies. The gluten quantification was determined by the R5 ELISA method approved by EU regulations.

RESULTS

Out of 66 oral hygiene and cosmetics, 62 products (94%) were found to be gluten-free (gluten level <20 ppm), while 4 (6%) (toothpastes = 3; lipsticks = 1) showed a gluten level >20 ppm (toothpastes: 20.7, 31.4, and 35 ppm; lipstick: 27.4 ppm). None of the selected products had ingredient derived from wheat, barley, or rye.

CONCLUSIONS

Gluten contamination is currently not an issue in a wide array of cosmetic and oral hygiene products that are commonly in the market.

Gluten contamination in food services and industry: A systematic review

Gluten-related disorders (GRD) affects approximately 10% of the general population. The only treatment for GRD is still so far is the lifelong complete exclusion of gluten from the daily diet. The correct information about the presence/absence of gluten in food is very important to this group. The present study aimed to evaluate the prevalence of gluten contamination in gluten-free industrial and non-industrial products. In this systematic review, 24 cross-sectional studies were analyzed. The authors developed specific search strategies for Science Direct, Scopus, Web of Science, Google Scholar and ProQuest Dissertations & Theses Global. The authors evaluated the methodological quality of the included studies using criteria from Meta-analysis of Statistics Assessment and Review Instrument (MASTARI). We performed the statistical meta-analysis by metafor package of R program. 95.83% (n = 23) of the studies presented positive results for contamination (over 20 ppm). In industrial food products, studies showed a contamination prevalence of 13.2% (95% CI: 10.8%-15.7%). In non-industrial food products, studies showed a contamination prevalence of 41.5% (95% CI: 16.6%-66.4%). Despite the non-industrial products presented higher contamination prevalence than the industrial products, the difference was not significant (p = 0.072). The findings indicate cross-contamination in industrialized and non-industrialized products. As expected, industrial products labeled as gluten-free showed a lower percentage of gluten-contamination than non-industrialized. Despite that, any contaminated sample found in this group present greater relevance than non-labeled foods. It indicates that foods labeled as "gluten-free" should not be considered safe for patients with GRD since information on the label regarding the presence/absence of gluten is unreliable. Therefore, any gluten-contamination in products labeled as gluten-free is a serious problem to whom present GRD. Further studies are needed to estimate gluten cross-contamination in food service meals and industry better.

New Protocol for Production of Reduced-Gluten Wheat Bread and Pasta and Clinical Effect in Patients with Irritable Bowel Syndrome: A randomised, Double-Blind, Cross-Over Study

It has been suggested that sourdough fermented products have beneficial health effects. Fungal proteases and selected sourdough lactic acid bacteria were used to produce wheat bread and pasta with a reduced-gluten content (<50% of traditional products). Fermentable oligo-, di- and mono- saccharides and polyols and amylase/trypsin inhibitors were also evaluated. The sensorial features of new products were similar to traditional ones. The efficacy of these new products in reducing the severity of symptoms in Irritable Bowel Syndrome (IBS) patients were compared to traditional bread and pasta using a randomized, crossover-controlled trial. While on a strict gluten-free diet, patients were randomized to consume a reduced- or normal-gluten diet for 2weeks; then, patients from both arms started the wash-out period of one week, and subsequently started the final 2-week period on a normal or reduced-gluten diet. Compared to normal-gluten content, the administration of a reduced-gluten content diet resulted in a decrease of the Visual Analogue Scale score (p = 0.042), while no differences were found in the IBS-Severity Score, Hospital Anxiety and Depression Scale, and IBS-Quality of Life. Data herein reported are novel encouraging findings that should spur a new avenue of research aiming to develop products specifically designed for IBS patients.

Gluten-Free Diet in Celiac Disease-Forever and for All?

The gluten-free diet is the only effective treatment available for celiac disease. However, it is difficult to adhere to and a closer look on the diet’s implementation and indications reveals several ambiguities: Not only is there controversy on the threshold of gluten that can be tolerated in the frame of a strict gluten-free diet, but it is also unclear whether the gluten-free diet is an appropriate treatment in patient subgroups with asymptomatic or potential celiac disease. Reports from a number of research groups suggest that a certain proportion of patients may effectively develop tolerance to gluten and thus become suitable for gluten reintroduction over time. In this review, we set out to create an overview about the current state of research as regards the definition of a strict gluten-free diet in terms of the gluten thresholds considered tolerable and the indication for a gluten-free diet in the absence of histological abnormalities or symptoms. Furthermore, we discuss the concept that a gluten-free diet must be followed for life by all patients.

Genetic and environmental factors affecting the expression of α-gliadin canonical epitopes involved in celiac disease in a wide collection of spelt (Triticum aestivum ssp. spelta) cultivars and landraces

BACKGROUND

Celiac disease (CD) is an autoimmune disorder affecting genetically predisposed individuals whose dietary gluten proteins trigger an inflammatory reaction in the small intestine. Gluten is found in the seeds of cereals like bread wheat (Triticum aestivum ssp. aestivum) and spelt (Triticum aestivum ssp. spelta). The development of new varieties lacking immunogenic peptides is one of the strategies currently investigated to address the CD problem. Among gluten proteins, α-gliadins display the strongest immunogenicity with four main T-cell stimulatory epitopes. The objective of this work was to study the expression of α-gliadin epitopes related to CD in a wide collection of 121 spelt accessions (landraces and varieties, spring and winter accessions) from different provenances, and to analyze the correlation between the presence of epitope sequences in gDNA and their expression (cDNA). The effect of environmental factors (harvest year and N fertilization) on the epitope expression was also investigated.

RESULTS

TaqMan probes targeting the canonical form of the epitopes were used to evaluate the epitope expression levels. Significant variations in the amount of epitope transcripts were identified between accessions and according to the provenances. Spring accessions showed a significantly higher immunogenicity than winter ones and no influence of spelt breeding on the epitope expression levels could be assessed when comparing landraces and varieties from Northwestern Europe. No correlation was observed between quantitative PCR results obtained from cDNA and gDNA for 45 accessions tested, stressing the need to use markers focusing on epitope transcripts rather than on genomic sequences. A relative stability of the amount of epitopes expressed by a same accession across four harvest years was detected. The fertilization strategy, evaluated through seven N fertilization modalities applied to two commercial spelt varieties, did not influence the epitope expression of the first variety, whereas it had a slight effect for the second one.

CONCLUSIONS

The results obtained in this work showed that the CD-related epitope expression greatly fluctuated among the spelt accessions studied. This expression was not correlated to the epitope genomic occurrence and environmental factors had almost no influence on the amount of epitope transcripts.

Gluten-free and low-FODMAP sourdoughs for patients with coeliac disease and irritable bowel syndrome: A clinical perspective

Wheat- and gluten-containing products are often blamed for triggering a wide range of gastrointestinal symptoms, and this has fueled demand for gluten-free products worldwide. The best studied 'gluten intolerance' is coeliac disease, an auto-immune disease that affects the small intestine. Coeliac disease occurs in 1% of the population and requires strict, life-long avoidance of gluten-containing foods as the only medical treatment. There is a larger group of individuals (around 10-15% of the population) who report a wide-range of gastrointestinal symptoms that respond well to a 'gluten-free diet', but who do not have coeliac disease - so called 'non-coeliac gluten sensitivity (NCGS)'. The team at Monash University has identified other factors in gluten-containing foods that may be responsible for symptoms in this group of individuals with so-called, NCGS. We have evidence that certain poorly absorbed short chain carbohydrates (called FODMAPs) present in many gluten-containing food products, induce symptoms of abdominal pain, bloating, wind and altered bowel habit (associated with irritable bowel syndrome, IBS). Our research has shown that FODMAPs, and not gluten, triggered symptoms in NCGS. Going forward, there are great opportunities for the food industry to develop low FODMAP products for this group, as choice of grain variety and type of food processing technique can greatly reduce the FODMAP levels in foods. The use of sourdough cultures in bread making has been shown to reduce the quantities of FODMAPs (mostly fructan), resulting in bread products that are well tolerated by patients with IBS. Greater interaction between biomedical- and food-scientists will improve understanding about the clinical problems many consumers face, and lead to the development of food products that are better tolerated by this group.

Preparation of a Defined Gluten Hydrolysate for Diagnosis and Clinical Investigations of Wheat Hypersensitivities

Gluten is the trigger for celiac disease (CD), non-celiac gluten/wheat sensitivity (NCGS), and wheat allergy. An oral food challenge is often needed for diagnosis, but there are no standardized gluten challenge materials with known composition available. To fill this gap, two materials, commercially available gluten and a food-grade gluten hydrolysate (pepgluten), were extensively characterized. Pepgluten was prepared from gluten by incubation with a pepsin dietary supplement and acetic acid at 37 °C for 120 min. The components of pepgluten were crude protein (707 mg/g), starch (104 mg/g), water (59 mg/g), fat (47 mg/g), dietary fiber (41 mg/g) and ash (11 mg/g). The protein/peptide fraction of pepgluten (1 g) contained equivalents derived from 369 mg gliadins and 196 mg glutenins, resulting in 565 mg total gluten equivalents, 25 mg albumins/globulins, 22 mg α-amylase/trypsin inhibitors and 48 mg pepsin capsule proteins. The slightly acidic, dough-like smell and bitter taste of pepgluten could be completely camouflaged in multivitamin juice with bitter lemon, grapefruit juice, or vegetable and fruit smoothies. Thus, pepgluten met the criteria for placebo-controlled challenges (active and placebo materials are identical regarding appearance, taste, smell, and texture) and is appropriate as a standard preparation for the oral food challenge and clinical investigations to study wheat hypersensitivities.

Evaluation of a Handheld Gluten Detection Device

A portable, handheld gluten detection device, the Nima sensor, is now available for consumers wishing to determine if gluten is present in food. By U.S. regulation, gluten-free foods should contain <20 ppm of gluten. Thirteen gluten-free foods (muffins, three different types of bread, three different types of pasta, puffed corn snack, ice cream, meatballs, vinegar and oil salad dressing, oatmeal, and dark chocolate) were prepared; each food was spiked on a weight to weight basis with gluten levels of 0, 5, 10, 20, 30, 40, and 100 ppm before processing or preparation. Unprocessed and processed foods were tested with the handheld gluten sensor and by two gluten-specific enzyme-linked immunosorbent assays (ELISAs) on the basis of the R5 and G12 monoclonal antibodies, respectively. The portable gluten detection device detected gluten in all food types at the 30-ppm addition level, failing to detect gluten in only 5 (6.4%) of 78 subsamples. At the 20-ppm addition level, the portable gluten detection device failed to detect gluten in one type of pasta but detected gluten residues in 63 (87.5%) of 72 other subsamples. The device was able to detect gluten at the 10-ppm addition level in 9 of the 13 food matrices (41 of 54 subsamples, 75.9%) but not in the three types of pasta and the puffed corn snack. The gluten-sensing device did not perform reliably at the 5-ppm addition level in 11 of 13 food matrices (exceptions: ice cream and muffins). In contrast, the ELISA methods were highly reliable at gluten addition levels of ≥10 ppm in all food matrices. The portable gluten detection device yielded a low percentage of false-positive results (4 of 111, 3.6%) in these food matrices. Thus, this handheld portable gluten sensor performed reliably in the detection of gluten in foods having ≥20 ppm of added gluten with only 18 (5.9%) of 306 failures, if results of the one type of pasta are excluded. The device worked with greater reliability as the gluten levels in the foods increased.

Cross-Contamination with Gluten by Using Kitchen Utensils: Fact or Fiction?

A risk of cross-contamination exists when preparing a gluten-free (GF) meal in kitchen facilities that usually handle gluten-containing (GC) foods. Cross-contamination with gluten may occur during the preparation or cooking process; however, published data are lacking on gluten cross-contamination from kitchenware. This study was conducted to determine whether cross-contamination occurs through shared domestic kitchenware and, if so, which cleaning method is most reliable for avoiding this cross-contamination. Kitchenware (wooden spoon, colander, ladle, and knife) previously used to cook and/or prepare GC foods was used for the preparation of GF foods (bread and pasta). The gluten concentration of the GF foods was then determined using an established enzyme-linked immunosorbent assay. A PCR assay was also used to detect the presence of wheat ω-gliadin DNA in the food samples. Three cleaning methods were assessed to determine the concentrations of gluten and wheat DNA in GF foods cooked with utensils cleaned directly after the preparation of GC foods. Contrary to our expectations, gluten was not detected in relevant and quantifiable amounts in our samples (<20 mg/kg). The cleaning method used did not influence gluten concentrations: all samples contained <10 mg/kg. Based on PCR analyses, the only sample with lower cycle threshold ( C_T) values (i.e., higher concentration of wheat DNA) was from the contaminated ladle used to serve GF pasta. This outcome led to the hypothesis that shared ladles pose a higher risk for contamination of GF foods than do shared wooden spoons, colanders, or knives. Cross-contamination with gluten in a kitchen environment may occur, but kitchen utensils used for preparing GC pasta and for cutting GC bread should not pose a relevant problem to patients with celiac disease, at least in a domestic environment.

Oat safety for celiac disease patients: theoretical analysis correlates adverse symptoms in clinical studies to contaminated study oats

Inclusion of oats in a gluten-free (GF) diet can provide whole grain nutritional benefits to celiac disease (CD) patients, but there has been debate regarding oat safety for these individuals. This is because of conflicting research findings, with inconsistencies attributed to varying CD subject's sensitivities to "pure" oats. Clinical trials to date have assumed oats provided to subjects to be lightly contaminated, if at all. This assumption is challenged here since oat's propensity to be "kernel" contaminated with gluten sources like wheat and barley has recently been shown to significantly complicate confirmation of a GF state. We therefore hypothesize that clinical studies may have inadvertently provided pill-like gluten kernels intermittently to study subjects, leading to adverse outcomes that could potentially explain inconsistencies between study conclusions. To test this theory, potential gluten contamination of oats used in a cross-section of 12 important oat feeding studies has been estimated, done according to descriptions of oats used, published contamination rates for various oat types, and study oat dosages. Expected gluten exposures were found to be at levels to elicit clinical effects in a large portion of CD patients, correlating with observed clinical reaction rates in those studies (P value = .0006). Estimated gluten doses were found insufficient, however, to affect morphological outcomes, whereas only 1 study had 1 case. Our analysis provides a new perspective with which to view oat safety study conclusions and justifies new clinical trials using today's higher-purity GF oats to settle the oat safety for CD patient debate.

An integrated, accurate, rapid, and economical handheld consumer gluten detector

Celiac disease, characterized by autoimmune reactions to dietary gluten, affects up to 3 million in the US and approximately 0.5%-1% globally. A strict, lifelong gluten-free diet is the only treatment. An economic, simple, accurate, rapid and portable gluten testing device would enable gluten-sensitive individuals to safeguard their food safety. We developed a novel solution, Nima™, a gluten sensor that integrates food processing, gluten detection, result interpretation and data transmission in a portable device, detecting gluten proteins at or below the accepted 20 ppm threshold. We developed specific monoclonal antibodies, an optimized lateral flow immunoassay strip, and one-step aqueous extraction. Compared with reference R5, Nima^TM antibodies (13F6 and 14G11) had 35- and 6.6-fold higher gliadin affinities, respectively. We demonstrated device performance using a comprehensive list of foods, assessing detection sensitivity, reproducibility, and cross-reactivity. Nima™ presented a 99.0% true positive rate, with a 95% confidence interval of 97.8%-100%.

All that a physician should know about gluten-free diet

Gluten-free diet (GFD) is the only definitive treatment for patients with celiac disease (CeD). Strict adherence to GFD improves the symptoms, nutritional deficiencies, and the overall well-being of the patients. The management of CeD is truly different and unique from the treatment of other medical or surgical diseases. While prescribing a GFD is easy, the key to the success lies in the dietary counseling by a nutrition specialist/physician and maintenance of adherence to the prescribed diet by the patient. When restricting gluten from all possible sources, it is pertinent to recommend a diet that is healthy and balanced for patients with celiac disease. Those following GFD must be counseled properly on the ways of balancing their diets and of avoiding cross contamination. They should be taught how to read food labels properly and given tips for dining out or during traveling. Regular follow up with patients is required for assessing the compliance and monitoring growth and the status of recovery. In this review article, we have compiled, for the physicians and gastroenterologists, the relevant information about GFD including counseling, adherence, nutritional adequacy, and many other related issues.

Outcome measures in coeliac disease trials: the Tampere recommendations

OBJECTIVE

A gluten-free diet is the only treatment option of coeliac disease, but recently an increasing number of trials have begun to explore alternative treatment strategies. We aimed to review the literature on coeliac disease therapeutic trials and issue recommendations for outcome measures.

DESIGN

Based on a literature review of 10 062 references, we (17 researchers and 2 patient representatives from 10 countries) reviewed the use and suitability of both clinical and non-clinical outcome measures. We then made expert-based recommendations for use of these outcomes in coeliac disease trials and identified areas where research is needed.

RESULTS

We comment on the use of histology, serology, clinical outcome assessment (including patient-reported outcomes), quality of life and immunological tools including gluten immunogenic peptides for trials in coeliac disease.

CONCLUSION

Careful evaluation and reporting of outcome measures will increase transparency and comparability of coeliac disease therapeutic trials, and will benefit patients, healthcare and the pharmaceutical industry.

Hypervigilance to a Gluten-Free Diet and Decreased Quality of Life in Teenagers and Adults with Celiac Disease

BACKGROUND AND AIMS

Avoidance of gluten is critical for individuals with celiac disease (CD), but there is also concern that "extreme vigilance" to a strict gluten-free diet may increase symptoms such as anxiety and fatigue, and therefore, lower quality of life (QOL). We examined the associations of QOL with energy levels and adherence to, and knowledge about, a gluten-free diet.

METHODS

This is a cross-sectional prospective study of 80 teenagers and adults, all with biopsy-confirmed CD, living in a major metropolitan area. QOL was assessed with CD-specific measures. Dietary vigilance was based on 24-h recalls and an interview. Knowledge was based on a food label quiz. Open-ended questions described facilitators and barriers to maintaining a gluten-free diet.

RESULTS

The extremely vigilant adults in our sample had significantly lower QOL scores than their less vigilant counterparts [(mean (SD): 64.2 (16.0) vs 77.2 (12.2), p = 0.004]. Extreme vigilance was also associated with greater knowledge [5.7 (0.7) vs 5.1 (0.8), p = 0.035]. Adults with lower energy levels had significantly lower overall QOL scores than adults with higher energy levels [68.0 (13.6) vs 78.9 (13.0), p = 0.006]. Patterns were similar for teenagers. Cooking at home and using internet sites and apps were prevalent strategies used by the hypervigilant to maintain a strict gluten-free diet. Eating out was particularly problematic.

CONCLUSION

There are potential negative consequences of hypervigilance to a strict gluten-free diet. Clinicians must consider the importance of concurrently promoting both dietary adherence and social and emotional well-being for individuals with CD.

Development and Validation of a Specific Self-Efficacy Scale in Adherence to a Gluten-Free Diet

The aim of this study was to develop a scale to assess the levels of specific self-efficacy in order to enhance adherence to a gluten-free diet and the life quality of celiac patients. Celiac disease is a chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed people. The only treatment is a strict lifelong gluten-free diet. Within the framework of Social Cognitive Theory, expectation of self-efficacy is understood as the degree in which a person believes himself to be capable of performing a certain task (e.g., adhering to a gluten-free diet), a construct which has been widely studied in its relation with adopting healthy behaviors, but scarcely in relation to celiac disease. A validation study was carried out in various stages: preparation of the protocol; construction of the questionnaire and a pilot run with 20 patients; validation of the scale with 563 patients and statistical analysis. A 25-item scale was developed. Feasibility was excellent (99.82% of participants completed all the questions). Factorial analysis pointed to the existence of five factors that explained 70.98% of the variance with a Cronbach alpha of 0.81 for the scale overall and between 0.64 and 0.90 for each factor. The scale showed a Spearman's Rho coefficient of 0.279 with the General self-efficacy Scale. This easily administered scale provides good psychometric properties for evaluating specific self-efficacy of celiac patients in adhering to treatment. It seeks to be the first scale that provides not only a measurement of specific self-efficacy in celiac disease, but also to determine its levels for each of the areas as a first step toward designing interventions of self-management and empowerment programs to cope with the disease.

Measuring Change In Small Intestinal Histology In Patients With Celiac Disease

Small intestinal histologic abnormalities in celiac disease include atrophy of the intestinal villi, hypertrophy of the crypts and lymphocytic infiltration of intraepithelial spaces and lamina propria. These findings are central to diagnosis and their severity and change over time are valuable to monitor disease course and response to therapy. Subjective methods to grade celiac disease histological severity include the Marsh-Oberhuber and Corazza-Villanacci systems. Quantitative histology uses villus height (Vh), crypt depth (Cd), and intra-epithelial lymphocyte count (per 100 enterocytes) to provide objective measures of histologic changes including Vh:Cd ratio. Here we examine the available literature regarding these methodologies and support the use of quantitative histology as the preferred method for accurately and reproducibly demonstrating change of relevant histologic end points over time. We also propose a Quantitative-Mucosal Algorithmic Rules for Scoring Histology (Q-MARSH) system to partially align quantitative histology results with the traditional Marsh, Marsh-Oberhuber, and Corazza-Villanacci systems. Q-MARSH can provide a standardized, objective, and quantitative histology scoring system for use as a clinical or research application.

Targeted liquid chromatography tandem mass spectrometry to quantitate wheat gluten using well-defined reference proteins

Celiac disease (CD) is an inflammatory disorder of the upper small intestine caused by the ingestion of storage proteins (prolamins and glutelins) from wheat, barley, rye, and, in rare cases, oats. CD patients need to follow a gluten-free diet by consuming gluten-free products with gluten contents of less than 20 mg/kg. Currently, the recommended method for the quantitative determination of gluten is an enzyme-linked immunosorbent assay (ELISA) based on the R5 monoclonal antibody. Because the R5 ELISA mostly detects the prolamin fraction of gluten, a new independent method is required to detect prolamins as well as glutelins. This paper presents the development of a method to quantitate 16 wheat marker peptides derived from all wheat gluten protein types by liquid chromatography tandem mass spectrometry (LC-MS/MS) in the multiple reaction monitoring mode. The quantitation of each marker peptide in the chymotryptic digest of a defined amount of the respective reference wheat protein type resulted in peptide-specific yields. This enabled the conversion of peptide into protein type concentrations. Gluten contents were expressed as sum of all determined protein type concentrations. This new method was applied to quantitate gluten in wheat starches and compared to R5 ELISA and gel-permeation high-performance liquid chromatography with fluorescence detection (GP-HPLC-FLD), which resulted in a strong correlation between LC-MS/MS and the other two methods.

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.

Determination of gluten consumption in celiac disease patients on a gluten-free diet

Background

Celiac disease (CD) patients adhering to a gluten-free diet (GFD) are exposed frequently to low levels of gluten that contribute to symptoms and persistent intestinal histologic damage.

Objective

We analyzed prior clinical data to determine how much gluten is accidentally consumed while on a GFD. The aim was to understand the range of gluten consumption for a wide distribution of CD patients.

Design

A meta-analysis was conducted on data from 2 different clinical programs: 1) measurements of gluten in stool and urine in CD and non-CD populations; and 2) analysis of data from trials for the investigational therapeutic latiglutenase. The stool and urine studies included controlled gluten challenges. A calibration factor was applied that allowed normal ingestion of gluten to be computed from the urine and stool measurements. From the latiglutenase trial data, a determination of gluten consumption was made by estimating how much gluten was eliminated from patients' diets due to a trial effect that led to improved histology even in the placebo group.

Results

The average inadvertent exposure to gluten by CD individuals on a GFD was estimated to be ∼150-400 (mean) and ∼100-150 (median) mg/d using the stool test and ∼300-400 (mean) and ∼150 (median) mg/d using the urine test. The analyses of the latiglutenase data for CD individuals with moderate to severe symptoms indicate that patients ingested significantly >200 mg/d of gluten.

Conclusions

These surrogate biomarkers of gluten ingestion indicate that many individuals following a GFD regularly consume sufficient gluten to trigger symptoms and perpetuate intestinal histologic damage.

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.

Younger age at diagnosis predisposes to mucosal recovery in celiac disease on a gluten-free diet: A meta-analysis

Background and aims

Persistent intestinal damage is associated with higher complication rates in celiac disease. We aimed to assess the potential modifiers of mucosal recovery.

Materials and methods

We screened databases (PubMed, Embase, Cochrane Trials, and Web of Science) for papers on celiac disease. Papers discussing (1) celiac patients (2) follow-up biopsy and (3) mucosal recovery after commencement of a gluten-free diet were included. The primary outcome was to produce a comprehensive analysis of complete mucosal recovery (i.e., Marsh 0 on follow-up). We compared children’s recovery ratios to those of adults. Patients following a strict gluten-free dietary regimen were included in a subgroup. Summary point estimates, 95% confidence intervals (CIs), and 95% predictive intervals (PIs) were calculated. Heterogeneity was tested with I²-statistic. The PROSPERO registration number is CRD42016053482.

Results

The overall complete mucosal recovery ratio, calculated from 37 observational studies, was 0.36 (CI: 0.28–0.44, PI: -0.12–0.84; I²: 98.4%, p<0.01). Children showed higher complete mucosal recovery ratio than adults (p<0.01): 0.65 (CI: 0.44–0.85, PI: -0.10–1.39; I²: 96.5%, p<0.01) as opposed to 0.24 (CI: 0.15–0.33, PI: -0.19–1.08; I²: 96.3%, p<0.01). In the strict dietary adherence subgroup, complete mucosal recovery ratio was 0.47 (CI: 0.24–0.70, PI: -0.47–1.41; I²: 98.8%, p<0.001). On meta-regression, diagnostic villous atrophy (Marsh 3) ratio (-8.97, p<0.01) and male ratio (+6.04, p<0.01) proved to be a significant determinant of complete mucosal recovery, unlike duration of gluten-free diet (+0.01, p = 0.62). The correlation between complete mucosal recovery ratio and age on diagnosis is of borderline significance (-0.03, p = 0.05).

Conclusions

There is considerable heterogeneity across studies concerning complete mucosal recovery ratios achieved by a gluten-free diet in celiac disease. Several celiac patients fail to achieve complete mucosal recovery even if a strict dietary regimen is followed. Younger age on diagnosis, less severe initial histologic damage and male gender predispose for achieving mucosal recovery.

Indications and Use of the Gluten Contamination Elimination Diet for Patients with Non-Responsive Celiac Disease

For the majority of patients diagnosed with celiac disease, once a gluten-free diet is initiated, symptoms improve within weeks and may completely resolve in months. However, up to 30% of patients may show signs, symptoms or persistent small intestinal damage after one year on a gluten-free diet. These patients require evaluation for other common GI etiologies and assessment of their celiac disease status in order to make a diagnosis and suggest treatment. Here, we propose an approach to evaluating patients with celiac disease with persistent symptoms, persistently elevated serology, and or persistent villous atrophy despite a gluten-free diet. We detail how to diagnose and distinguish between non-responsive and refractory celiac disease. Finally, we introduce the indications for use of the gluten contamination elimination diet and provide information for practitioners to implement the diet when necessary in their practice.

Latiglutenase Improves Symptoms in Seropositive Celiac Disease Patients While on a Gluten-Free Diet

BACKGROUND AND AIMS

Celiac disease (CD) is a widespread condition triggered by dietary gluten and treated with a lifelong gluten-free diet (GFD); however, inadvertent exposure to gluten can result in episodic symptoms. A previous trial of latiglutenase (clinicaltrials.gov; NCT01917630), an orally administered mixture of two recombinant gluten-specific proteases, was undertaken in symptomatic subjects with persistent injury. The primary endpoint for histologic improvement was not met, presumably due to a trial effect. In this post hoc analysis, we investigated the efficacy of latiglutenase for reducing symptoms in subgroups of the study participants based on their seropositivity.

METHODS

The study involved symptomatic CD patients following a GFD for at least one year prior to randomization. Patients were treated for 12 weeks with latiglutenase or placebo. Of 398 completed patients, 173 (43%) were seropositive at baseline. Symptoms were recorded daily, and weekly symptom scores were compiled. p values were calculated by analysis of covariance.

RESULTS

A statistically significant, dose-dependent reduction was detected in the severity and frequency of symptoms in seropositive but not seronegative patients. The severity of abdominal pain and bloating was reduced by 58 and 44%, respectively, in the cohort receiving the highest latiglutenase dose (900 mg, n = 14) relative to placebo (n = 54). Symptom improvement increased from week 6 to week 12. There was also a trend toward greater symptom improvement with greater baseline symptom severity.

CONCLUSIONS

Seropositive CD patients show symptomatic improvement from latiglutenase taken with meals and would benefit from the availability of this treatment.

Lack of immunogenicity of hydrolysed wheat flour in patients with coeliac disease after a short-term oral challenge

BACKGROUND

A gluten-free diet is currently the only reliable therapeutic strategy that is approved for coeliac disease (CD). For many patients, however, compliance remains inadequate.

AIM

To investigate the immunogenicity of wheat flour that was pre-treated with selected lactobacilli and fungal proteases (hydrolysed wheat gluten) in coeliac patients.

METHODS

The immunogenicity of hydrolysed wheat gluten was evaluated both in vitro in intestinal T cell lines (TCLs) and in vivo in treated CD patients after a short-term gluten challenge. Twenty treated CD patients were enrolled and equally randomised into two groups. The patients ate bread that was prepared with hydrolysed wheat flour or natural wheat flour (10 g of gluten/d for 3 days). The interferon (INF)-γ responses to natural gliadin and a 33-mer peptide were assessed by the enzyme-linked immunospot (ELISPOT) assay on peripheral blood mononuclear cells (PBMCs) both before and 6 days after the start of the challenge.

RESULTS

Hydrolysed wheat was not able to activate the TCLs from the coeliac intestinal mucosa. Consistent with the in vitro results, no significant increase in INF-γ secretion was observed in patients who consumed hydrolysed wheat flour. Conversely, the consumption of natural wheat gluten mobilised INF-γ secreting cells in the blood (P<.05).

CONCLUSIONS

We confirm that fermentation of wheat flour with sourdough lactobacilli and fungal proteases is capable of abolishing the T cell immunogenicity of gluten in coeliac patients. Our data also validate the short-term oral challenge as a useful tool for testing the efficacy of novel therapeutic approaches.

Long term gluten consumption in adults without celiac disease and risk of coronary heart disease: prospective cohort study

Objective To examine the association of long term intake of gluten with the development of incident coronary heart disease.Design Prospective cohort study.Setting and participants 64 714 women in the Nurses' Health Study and 45 303 men in the Health Professionals Follow-up Study without a history of coronary heart disease who completed a 131 item semiquantitative food frequency questionnaire in 1986 that was updated every four years through 2010.Exposure Consumption of gluten, estimated from food frequency questionnaires.Main outcome measure Development of coronary heart disease (fatal or non-fatal myocardial infarction).Results During 26 years of follow-up encompassing 2 273 931 person years, 2431 women and 4098 men developed coronary heart disease. Compared with participants in the lowest fifth of gluten intake, who had a coronary heart disease incidence rate of 352 per 100 000 person years, those in the highest fifth had a rate of 277 events per 100 000 person years, leading to an unadjusted rate difference of 75 (95% confidence interval 51 to 98) fewer cases of coronary heart disease per 100 000 person years. After adjustment for known risk factors, participants in the highest fifth of estimated gluten intake had a multivariable hazard ratio for coronary heart disease of 0.95 (95% confidence interval 0.88 to 1.02; P for trend=0.29). After additional adjustment for intake of whole grains (leaving the remaining variance of gluten corresponding to refined grains), the multivariate hazard ratio was 1.00 (0.92 to 1.09; P for trend=0.77). In contrast, after additional adjustment for intake of refined grains (leaving the variance of gluten intake correlating with whole grain intake), estimated gluten consumption was associated with a lower risk of coronary heart disease (multivariate hazard ratio 0.85, 0.77 to 0.93; P for trend=0.002).Conclusion Long term dietary intake of gluten was not associated with risk of coronary heart disease. However, the avoidance of gluten may result in reduced consumption of beneficial whole grains, which may affect cardiovascular risk. The promotion of gluten-free diets among people without celiac disease should not be encouraged.