Wheat Allergy Research Articles

Autoimmunity Features in Patients With Non-Celiac Wheat Sensitivity.

Nonceliac wheat sensitivity (NCWS) is characterized by intestinal and extraintestinal manifestations consequent to wheat ingestion in subjects without celiac disease and wheat allergy. Few studies investigated the relationship between NCWS and autoimmunity. The aim of this study is to evaluate the frequency of autoimmune diseases (ADs) and autoantibodies in patients with NCWS. Ninety-one patients (13 men and 78 women; mean age of 40.9 years) with NCWS, recruited in a single center, were included. Seventy-six healthy blood donors (HBD) and 55 patients with a diagnosis of irritable bowel syndrome (IBS) unrelated to NCWS served as controls. Autoantibodies levels were measured. Human leukocyte antigen haplotypes were determined, and duodenal histology performed in all patients carrying the DQ2/DQ8 haplotypes. Participants completed a questionnaire, and their medical records were reviewed to identify those with ADs. Twenty-three patients with NCWS (25.3%) presented with ADs; autoimmune thyroiditis (16 patients, 17.6%) was the most frequent. The frequency of ADs was higher in patients with NCWS than in HBD (P = 0.002) and in patients with IBS (P = 0.05). In the NCWS group, antinuclear antibodies tested positive in 71.4% vs HBD 19.7%, and vs patients with IBS 21.8% (P < 0.0001 for both). The frequency of extractable nuclear antigen antibody (ENA) positivity was significantly higher in patients with NCWS (21.9%) than in HBD (0%) and patients with IBS (3.6%) (P = 0.0001 and P = 0.004, respectively). Among the patients with NCWS, 9.9% tested positive for antithyroglobulin, 16.5% for antithyroid peroxidase, and 14.3% for antiparietal cell antibodies; frequencies were not statistically different from controls. The presence of ADs was related to older age at NCWS diagnosis, female sex, duodenal lymphocytosis, and eosinophil infiltration. One in 4 patients with NCWS suffered from AD, and serum antinuclear antibodies were positive in a very high percentage of cases. These data led us to consider NCWS to be associated to ADs.

Gluten proteome comparison among durum wheat genotypes with different release date

In order to deepen insight into durum wheat prolamin composition in relation to both end use quality and gluten related disorders, a phenotyping of four genotypes of different release date and technological performance was carried out. A proteomic approach integrated with the evaluation of protein aggregation level, amino acid composition and reactivity to G12 monoclonal antibody, was adopted. The degree of polymerization, estimated as unextractable polymeric proteins (UPP), was positively influenced by Cys-rich proteins (Glu-B3 LMW-GS), with Saragolla showing up to 40% higher values than other genotypes. The proteomic assessment allowed to identify proteins involved in gluten related disorders. In particular, ω5-gliadin involved in wheat allergy (WA), resulted markedly over-expressed in the old landrace Dauno III, up to four-fold than in modern Saragolla. A marked influence of genotype on the expression level of gliadins containing toxic epitopes (TECP) was observed with the more recent genotypes showing lower values (−53%). Also, reactivity to G12 moAb resulted higher in the two old genotypes consistently to their higher celiac disease (CD) toxicity evaluated by the proteomic approach. In conclusion a better gluten composition for processing seems to be associated to a lower expression level of CD toxic peptides and Tri a 19.

Celiac Disease and Non-celiac Wheat Sensitivity: State of Art of Non-dietary Therapies.

Gluten related disorders (GRD), which include celiac disease, non-celiac wheat sensitivity and wheat allergy are heterogeneous conditions triggered by ingestion of gluten-containing grains. Together, their prevalence is estimated to be ~5% in the general population, however, in the last years the number of diagnoses has been rapidly increasing. To this day, the gold standard treatment for these disorders is the complete removal of gluten-containing grains from the diet. Although this therapy results effective in the majority of patients, up to 30% of individuals affected by GRD continue to present persistent symptoms. In addition, gluten-free diet has been shown to have poor nutritional quality and to cause a socio-economic burden in patients' quality of life. In order to respond to these issues, the scientific community has been focusing on finding additional and adjuvant non-dietary therapies. In this review, we focus on two main gluten related disorders, celiac disease and non-celiac wheat sensitivity. We delineate the actual knowledge about potential treatments and their relative efficacy in pre-clinical and clinical trials.

Clinical Characteristics and Proposed Wheat-Cofactor Challenge Protocol with a High Diagnostic Yield in Adult-Onset IgE-Mediated Wheat Allergy.

BackgroundIgE-mediated wheat allergy in adults can be childhood or adulthood onset. Adult-onset wheat allergy has been reported, but data on clinical characteristics and practical food challenge protocols are scarce.ObjectiveWe aimed to describe the clinical characteristics of adult-onset wheat allergy, laboratory results, and outcomes of a modified 3-day challenge protocol using a combination of aspirin, wheat, and exercise.Patients and MethodsPatients with histories compatible with adult-onset wheat allergy were recruited from Siriraj Hospital, Thailand. Clinical history, skin prick tests (SPTs), and specific IgE (sIgE) levels were ascertained. Patients with no food challenge contraindications were asked to volunteer for wheat challenge. A modified 3-day protocol using 300 mg of acetylsalicylic acid, 60–75 g of wheat flour, and exercise was used for confirmatory diagnosis of conventional wheat allergy (WA) and wheat-dependent exercise-induced anaphylaxis (WDEIA).ResultsThirty-three patients were recruited. The mean age of onset was 29.7 years (SD 10.5). SPTs yielded positivity rates of 9.1%, 84.8%, and 81.8% in commercial wheat, in-house gliadin, and in-house glutenin extracts, respectively. sIgE yielded a positivity rate of 61% and 88% in wheat and ω5-gliadin, respectively. Eighteen patients underwent oral wheat challenges. Of these, 17 patients (94.4%) had positive challenges leading to definite diagnoses of WA (35%), and WDEIA (65%). One WDEIA patient developed hypotensive anaphylaxis in the protocol.ConclusionWDEIA was the most common phenotype. Our modified 3-day protocol could differentiate WA and WDEIA and yielded a high positivity rate (94.4%). It should be used cautiously as severe reactions can occur.

Noncoeliac wheat sensitivity and diet.

Noncoeliac gluten sensitivity (NCGS) can be suspected after exclusion of coeliac disease and wheat allergy. However, poorly understood pathogenesis of the NCGS, lack of gold standard for diagnosis and agreement in the definition for the NCGS condition, open the space for future investigation. This review aims to give an overview on the diagnosis and effective diet composition in the treatment of NCGS symptoms. It appears that a diet low in fermentable oligo, di, and monosaccharides and polyols (FODMAPs) and gluten-free diet play a prominent role in the strategy of NCGS management. Considering available evidence with respect to diagnostic tools, it is challenging to prepare a standard guideline for NCGS diagnosis and treatment with clear cut-offs for symptom reduction/improvement that could directly be translated into test results. Nutritional support, including the use of pre/probiotics, has to be tailored to the individual situation of NCGS patients. The exclusion of such components of wheat as amylase/trypsin inhibitors, wheat-germ agglutinins, or free of FODMAPs diet can reduce clinical symptoms of NCGS. The further investigation on microbiota changes may strengthen the knowledge in this area, where the major challenge is to develop biomarkers for NCGS investigation.

Reduction of Allergenic Potential in Bread Wheat RNAi Transgenic Lines Silenced for CM3, CM16 and 0.28 ATI Genes

Although wheat is used worldwide as a staple food, it can give rise to adverse reactions, for which the triggering factors have not been identified yet. These reactions can be caused mainly by kernel proteins, both gluten and non-gluten proteins. Among these latter proteins, α-amylase/trypsin inhibitors (ATI) are involved in baker’s asthma and realistically in Non Celiac Wheat Sensitivity (NCWS). In this paper, we report characterization of three transgenic lines obtained from the bread wheat cultivar Bobwhite silenced by RNAi in the three ATI genes CM3, CM16 and 0.28. We have obtained transgenic lines showing an effective decrease in the activity of target genes that, although showing a higher trypsin inhibition as a pleiotropic effect, generate a lower reaction when tested with sera of patients allergic to wheat, accounting for the important role of the three target proteins in wheat allergies. Finally, these lines show unintended differences in high molecular weight glutenin subunits (HMW-GS) accumulation, involved in technological performances, but do not show differences in terms of yield. The development of new genotypes accumulating a lower amount of proteins potentially or effectively involved in allergies to wheat and NCWS, not only offers the possibility to use them as a basis for the production of varieties with a lower impact on adverse reaction, but also to test if these proteins are actually implicated in those pathologies for which the triggering factor has not been established yet.

Allelic variation of gliadin-encoding genes in a collection of tetraploid wheat genotypes

Wheat is one of the main crops bred worldwide. Durum wheat, specifically, is a key element of the Mediterranean diet, representing an élite crop grown in Italy. Durum wheat nutritional and technological values are largely due to the grain protein content (GPC), a complex genetic trait strongly affected by environmental factors and management practices. In the last decades, several breeding programs have been focused on improving GPC by both traditional and innovative approaches. Among seed storage proteins, prolamins, including both gliadins and glutenins, represent the major component. These two classes of proteins are indeed responsible of gluten formation and confer the extensibility and elasticity to the dough. Besides being of crucial importance for both technological properties and rheological characteristics, prolamins, and especially gliadins, have been found to be major triggers for human health, as involved in a number of wheat consumption-related conditions, such as the celiac disease, non-celiac gluten sensitivity, defined as the onset of a variety of manifestations related to wheat, rye and barley ingestion, and wheat allergies, both due to wheat ingestion or inhalation (of flour or pollen). The identification of loci responsible for the gliadin expression, and particularly of polymorphism in the aforementioned genes, which could result in a lower immunogenic/toxic potential, could be of great importance in breeding programs. For this purpose, we screened a collection of tetraploid wheat genotypes for allelic variants of annotated gliadin genes in the durum wheat genome, in order to identify genetic resources available to breeders to improve wheat nutritional and technological properties. Phylogenetic analysis among different species of Triticum genus and an in silico expression data analysis may also be useful in the exploitation of the complex scenario of gliadin–glutenin interaction and gluten role in the adverse reactions due to wheat consumption.

CRISPR-Cas9 Multiplex Editing of the α-Amylase/Trypsin Inhibitor Genes to Reduce Allergen Proteins in Durum Wheat

Wheat and its derived foods are widespread, representing one of the main food sources globally. During the last decades, the incidence of disorders related to wheat has become a global issue for the human population, probably linked to the spread of wheat-derived foods. It has been ascertained that structural and metabolic proteins, like α-amylase/trypsin inhibitors (ATI), are involved in the onset of wheat allergies (bakers’ asthma) and probably Non-Coeliac Wheat Sensitivity (NCWS). The ATI are a group of exogenous protease inhibitors, which are encoded by a multigene family dispersed over several chromosomes in durum and bread wheat. WTAI-CM3 and WTAI-CM16 subunits are considered among the main proteins involved in the onset of bakers’ asthma and probably NCWS. A CRISPR-Cas9 multiplexing strategy was used to edit the ATI subunits WTAI-CM3 and WTAI-CM16 in the grain of the Italian durum wheat cultivar Svevo with the aim to produce wheat lines with reduced amount of potential allergens involved in adverse reactions. Using a marker gene-free approach, whereby plants are regenerated without selection agents, homozygous mutant plants without the presence of CRISPR vectors were obtained directly from T0 generation. This study demonstrates the capability of CRISPR technology to knock out immunogenic proteins in a reduced time compared to conventional breeding programmes. The editing of the two target genes was confirmed either at molecular (sequencing and gene expression study) or biochemical (immunologic test) level. Noteworthy, as a pleiotropic effect, is the activation of the ATI 0.28 pseudogene in the edited lines.

Symptoms of gluten ingestion in patients with non-celiac gluten sensitivity: A randomized clinical trial.

Non-celiac gluten sensitivity (NCGS) is the presence of symptoms induced by gluten and relieved by a gluten-free diet (GFD) in patients without celiac disease or wheat allergy. Studies are mixed as to whether gluten is the main symptom trigger in patients with NCGS. Gluten immunogenic peptides (GIPs) in stool and urine are novel methods to monitor GFD compliance. Few studies have investigated their use in patients with NCGS. The aim of this study was to assess whether patients with NCGS have increased symptoms with gluten ingestion and to assess compliance with the GFD using stool and urine GIPs. This was a prospective, randomized, double-blinded crossover trial evaluating symptoms in patients with NCGS. Thirty patients with NCGS and 43 healthy controls were placed on a GFD. Patients received 0.5 or 2 g/d of gluten for 7 d each. The remaining weeks, they received placebo for a total of 4 wk. Symptoms were evaluated weekly using the Celiac Symptom Index (CSI). Urine and stool samples were collected weekly and measured for the detection of GIPs to detect exposure to gluten. There was no difference in symptom severity within the NCGS group whether receiving placebo or gluten (32.69 versus 31.54, P=0.64). Patients with NCGS had significantly higher CSI scores at baseline than healthy controls. Patients with NCGS were less likely to have stool and urine GIPs than healthy patients. Patients with NCGS were more adherent to the GFD based on stool and urine GIP results. Patients with NCGS had increased symptom severity at baseline compared with healthy controls. Neither group had significantly increased symptoms after ingestion of gluten.

Localized abdominal urticaria: A distinct clinical phenotype of wheat allergy in young children

Localized abdominal urticaria: A distinct clinical phenotype of wheat allergy in young children

Pitfalls in the Diagnosis of Coeliac Disease and Gluten-Related Disorders.

The spectrum of gluten-related disorders (GRD) has emerged as a relevant phenomenon possibly impacting on health care procedures and costs worldwide. Current classification of GRD is mainly based on their pathophysiology, and the following categories can be distinguished: immune-mediated disorders that include coeliac disease (CD), dermatitis herpetiformis (DH), and gluten ataxia (GA); allergic reactions such as wheat allergy (WA); and non-coeliac gluten sensitivity (NCGS), a condition characterized by both gastrointestinal and extra-intestinal symptoms subjectively believed to be induced by the ingestion of gluten/wheat that has recently gained popularity. Although CD, DH, and WA are well-defined clinical entities, whose diagnosis is based on specific diagnostic criteria, a diagnosis of NCGS may on the contrary be considered only after the exclusion of other organic disorders. Neither allergic nor autoimmune mechanisms have been found to be involved in NCGS. Mistakes in the diagnosis of GRD are still a relevant clinical problem that may result in overtreatment of patients being unnecessary started on a gluten-free diet and waste of health-care resources. On the basis of our clinical experience and literature, we aim to identify the main pitfalls in the diagnosis of CD and its complications, DH, and WA. We provide a practical methodological approach to guide clinicians on how to recognize and avoid them.

Slow low-dose oral immunotherapy: Threshold and immunological change

BackgroundWe examined the feasibility, efficacy and safety of slow low-dose oral immunotherapy (SLOIT) for egg, milk, wheat allergies, with accepted severity-stratified initial and maintenance doses. MethodsChildren with food allergies defined by low-dose oral food challenges (LD-OFCs) to hen's egg (cumulative protein dose up to 983 mg, n = 133), cow's milk (287 mg, n = 50), and wheat (226 mg, n = 45) were recruited. Participants were divided into two groups [SLOIT and control (complete avoidance]) based on their preferences. Participants who selected SLOIT were instructed to take the safe dose daily, with monthly increases, aiming to increase the dose by 10 times in one year. The primary outcome was the proportion of participants who passed the LD-OFCs following 1 year of therapy. ResultsThe participants in SLOIT group ingested their antigen 92.9% of the therapy's day on average. The proportion of participants who passed LD-OFCs was 35.9% (61/170) in the SLOIT group and 8.7% (4/46) in the control group (P < .001); no large differences were observed among allergens. Among the subjects who failed LD-OFCs, the median change in the total dose in the LD-OFC was 235% (interquartile range: 100%–512%) in the SLOIT group and 100% (42%–235%) in the control group (P < .001). Provoked allergic symptoms were observed in only 0.58% (280/48,486) per programmed intake and approximately 50% of the SLOIT group did not experience any obvious allergic symptoms throughout therapy. ConclusionsSLOIT showed significant feasibility, efficacy and safety, providing a promising option to manage patients with severe food allergies.

Pilot study on non-celiac gluten sensitivity: effects of Bifidobacterium longum ES1 co-administered with a gluten-free diet.

Bifidobacterium longum ES1 is a strain probiotic, colonizing the human gut and capable of a degradative action on gliadin. In an attempt to find new nutritional solutions aimed at improving the quality of life of patients with non-celiac gluten sensitivity (NCGS) we evaluated the effectiveness of this strain, in association with a gluten-free diet, comparing its efficacy versus diet therapy alone. The experimental design included a non-randomized, open-label, 1:1 intervention study in parallel groups. Enrolled patients with symptoms attributable to NCGS, and with negative diagnoses of both wheat allergy and celiac disease, were included in this three-month trial divided into four outpatient visits (baseline, T1, T2 and T3). Fifteen patients for each group completed the experimental protocol. Our results showed that a combination of diet and probiotic determined a more significant reduction in the frequency and intensity of intestinal and extra-intestinal symptoms, and a clear improvement in stool consistency. Although the study was carried out on a small number of patients, the results of our pilot trial suggest that a combined strategy of naturally gluten-free diet therapy with administration of the probiotic strain ES1 appears to offer a greater advantage than the dietary regime alone in improving the clinical symptomatic picture and in stabilizing the intestinal microbiota.

Mechanisms of Wheat Allergenicity in Mice: Comparison of Adjuvant-Free vs. Alum-Adjuvant Models.

Wheat protein is considered a major type of food allergen in many countries including the USA. The mechanisms of allergenicity of wheat proteins are not well understood at present. Both adjuvant-based and adjuvant-free mouse models are reported for this food allergy. However, it is unclear whether the mechanisms underlying wheat allergenicity in these two types of models are similar or different. Therefore, we compared the molecular mechanisms in a novel adjuvant-free (AF) model vs. a conventional alum-adjuvant (AA) model of wheat allergy using salt-soluble wheat protein (SSWP). In the AF model, Balb/cJ mice were sensitized with SSWP via skin exposure. In the AA model, mice were sensitized by an intraperitoneal injection of SSWP with alum. In both models, allergic reactions were elicited using an identical protocol. Robust IgE as well as mucosal mast cell protein-1 responses were elicited similarly in both models. However, an analysis of the spleen immune markers identified strikingly different molecular activation patterns in these two models. Furthermore, a number of immune markers associated with intrinsic allergenicity were also identified in both models. Since the AF model uses skin exposure without an adjuvant, the mechanisms in the AF model may more closely simulate the human wheat allergenicity mechanisms from skin exposure in occupational settings such as in the baking industry.

Clinical and in vitro cross-reactivity of cereal grains in children with IgE-mediated wheat allergy

Introduction and ObjectivesWheat and cereal grains have a broad range of cross-reactivity, but the clinical relevance of this cross-reactivity is uncertain. This study aimed to evaluate clinical and in vitro cross-reactivity with barley, oat, and Job’s tears among wheat-allergic patients. Materials and MethodsPatients aged 5 to 15 years with IgE-mediated wheat allergy were enrolled. Skin prick test (SPT) and specific IgE (sIgE) to wheat, barley, and oat, and SPT to Job’s tears were performed. Oral food challenge (OFC) was conducted if the SPT was ≤5 mm in size and there was no history of anaphylaxis to each grain. Profiles of sIgE bound allergens of wheat, barley, and oat, and inhibition ELISA of IgE binding to barley and oat with wheat were performed. ResultsTen patients with a median age of 8 years were enrolled. Nine of those patients had a history of wheat anaphylaxis. The median SPT size and sIgE level to wheat was 7.3 mm and 146.5 kUA/l, respectively. The cross-reactivity rate for barley, oat, and Job’s tears was 60.0%, 33.3%, and 20.0%, respectively. Significantly larger SPT size and higher sIgE level were observed in patients with positive cross-reactivity to barley and oat when compared to patients without cross-reactivity. Barley and oat extracts inhibited 59% and 16% of sIgE bound to wheat gliadins and glutenins, respectively. ConclusionThe cross-reactivity rate was quite low for oat and Job’s tears compared to that of barley; therefore, avoidance of all cereal grains may be unnecessary in patients with severe wheat allergy.

Induction of Oral Tolerance by Pepsin-Digested Gliadin Retaining T Cell Reactivity in a Mouse Model of Wheat Allergy

Background: Wheat is known as the most widely consumed food all over the world. Although many types of wheat allergy have been recognized, their treatment still has a long way to go due to the complex pathogenesis. Oral immunotherapy (OIT) is under investigation for the treatment of wheat allergies. Previous studies have demonstrated that OIT using intact wheat allergens can induce tolerance, but is accompanied by a high risk of anaphylactic reactions. Objectives: Our objective was to prepare modified wheat allergens with hypoallergenic and tolerance-inducing properties to reduce adverse effects during immunotherapy. Methods: Wheat gliadin was degraded by hydrolysis with pepsin and trypsin, and then the hydrolysate was deamidated with hydrochloric acid. The IgE-binding capacity and T cell reactivity of the degraded gliadins were evaluated in vitro. Pepsin-digested gliadin (peptic-GLI) was applied in a mouse model to investigate whether it would induce oral tolerance. Results: Degradation with pepsin decreased IgE-binding capacity and maintained T cell reactivity. Oral administration of peptic-GLI to mice before sensitization and challenge with gliadin could significantly suppress the production of IgE, IgG1, and type 2 T helper cytokines. Moreover, the development of anaphylactic reactions and allergic responses of the small intestine induced by gliadin challenge were inhibited by oral administration of peptic-GLI. Conclusions: The findings of this study indicate that peptic-GLI with low allergenicity and potential for tolerance induction may become useful in wheat immunotherapy with less adverse effects.

Prevalence of Adverse Reactions to Gluten and People Going on a Gluten-Free Diet: A Survey Study Conducted in Brazil.

Background: The prevalence of gluten-related disorders (GRD) and adherence to a gluten-free diet (GFD) remains unknown in Brazilian population and there is no published information on the scientific literature about the proportion of Brazilians that were diagnosed with a gluten-related disorder. Thus, the aim of this work was to estimate the prevalence of GRDs and adherence to a GFD by self-report in adult Brazilian population. Materials and Methods: A questionnaire-based cross-sectional study was conducted in two Brazilian cities. Results: The response rate was 93.2% (1630/1749). The self-reported prevalence rates were (95% CI): adverse reactions to gluten 10.06% (8.64–11.62); gluten sensitivity 2.33% (1.65–3.18); physician-diagnosed celiac disease 0.3% (0.09–0.71); non-celiac gluten sensitivity 1.71% (1.14–2.47); wheat allergy 0.79% (0.42–1.36); adherence to gluten-free diet 7.48% (6.25–8.87); gluten avoiders 15.21% (13.5–17.05). Among those who were following a GFD (n = 122), 65.6% (n = 80) of them reported that they did not develop symptoms after wheat/gluten ingestion and 50% (n = 61) were following the diet without medical/dietitian advice. The main motivation for following a GFD in the self-reported and non-self-reported gluten sensitivity groups were the symptoms triggered after wheat/gluten ingestion (86.8%) and weight control (57.1%), respectively. Conclusions: Implementation of programs to increase awareness about GRDs among healthcare professionals and giving scientifically sound information to the general population about the risks and benefits for following a GFD are desirable actions in Brazil. The results also add to the growing body of evidence for highlighting the under-diagnosis of GRD and the trend for following a GFD in Latin America.

Prevention of baker's asthma.

Baker's allergy and asthma continue to represent an important contributor of occupational asthma globally. This review identified recent studies related to the prevention of baker's allergy and asthma. Studies with respect to regulatory exposure standards, workplace control measures aimed at reduction of flour dust exposures, surveillance programmes (exposure monitoring, medical surveillance) and workplace information, education and training programmes were identified. Detailed knowledge on risk factors and detection methods to assess exposure and early identification of high-risk workers exist, but workplace control measures remain sub-optimal because they are rarely multifaceted. This is compounded by the lack of health-based exposure standards globally. Exposure level monitoring and medical surveillance are integral to assessing effectiveness of preventive strategies. Triage systems for optimizing the efficiency of medical surveillance programmes show promise, but need replication in different contexts. Future studies need to focus on evaluating the relevance and quantification of peak exposures in increasing risk; developing standardized respiratory questionnaires for medical surveillance; and further exploration of serial fractional exhaled nitric oxide (FeNO) measurements as an adjunct to allergic sensitization for the early identification of baker's asthma and assessing the long-term impact of interventions.

Long-term efficacy of oral immunotherapy for hen's egg, cow's milk, and wheat allergies in children

Long-term efficacy of oral immunotherapy for hen's egg, cow's milk, and wheat allergies in children

Serum zonulin and its diagnostic performance in non-coeliac gluten sensitivity

ObjectiveNon-coeliac gluten sensitivity (NCGS) is characterised by intestinal and extraintestinal symptoms related to the ingestion of gluten-containing foods, in the absence of coeliac disease (CD) and wheat allergy. No biomarkers...