The spectrum of noncoeliac gluten sensitivity

Peptidomics analysis of in vitro digested wheat breads: Effect of genotype and environment on protein digestibility and release of celiac disease and wheat allergy related epitopes

Wheat proteins can trigger immunogenic reactions due to their resistance to digestion and immunostimulatory epitopes. Here, we investigated the peptidomic map of partially digested bread samples and the fingerprint of epitope diversity from 16 wheat genotypes grown in two environmental conditions. Flour protein content and composition were characterized; gastric and jejunal peptides were quantified using LC-MS/MS, and genotypes were classified into high or low bread protein digestibility. Differences in flour protein content and peptide composition distinguish high from low digestibility genotypes in both growing environments. No common peptide signature was found between high- and low-digestible genotypes; however, the celiac or allergen epitopes were noted not to be higher in low-digestible genotypes. Overall, this study established a peptidomic and epitope diversity map of digested wheat bread and provided new insights and correlations between weather conditions, genotypes, digestibility and wheat sensitivities such as celiac disease and wheat allergy.

γδ+ T-Cells Is a Useful Biomarker for the Differential Diagnosis between Celiac Disease and Non-Celiac Gluten Sensitivity in Patients under Gluten Free Diet

BACKGROUND

The differential diagnosis between patients with celiac disease (CD) and non-celiac gluten sensitivity (NCGS) is difficult when a gluten-free diet (GFD) has been initiated before the diagnostic work-up. Isolated increases in TCRγδ+ and celiac lymphogram (increased TCRγδ+ plus decreased CD3-) may enable differential diagnosis in this challenging clinical setting. This study evaluated: (1) the accuracy of %TCRγδ+ and celiac lymphogram for diagnosing CD before and after GFD and for differentiation with NCGS; (2) TCRγδ+ kinetics at baseline and after starting GFD in both CD and NCGS.

METHODS

The inclusion criteria were patients with CD (n = 104), NCGS (n = 37), and healthy volunteers (n = 18). An intestinal biopsy for intraepithelial lymphogram by flow cytometry was performed at baseline and after GFD. The optimal cutoff for CD diagnostic accuracy was established by maximizing the Youden index and via logistic regression.

RESULTS

%TCRγδ+ showed better diagnostic accuracy than celiac lymphogram for identifying CD before and after GFD initiation. With a cutoff > 13.31, the accuracy for diagnosing CD in patients under GFD was 0.88 [0.80-0.93], whereas the accuracy for diagnosing NCGS (%TCRγδ+ ≤ 13.31) was 0.84 [0.76-0.89]. The percentage of TCRγδ+ cells showed differential kinetics between CD (baseline 22.7% [IQR, 16.4-33.6] vs. after GFD 26.4% [IQR, 17.8-36.8]; p = 0.026) and NCGS (baseline 9.4% [IQR, 4.1-14.6] vs. after GFD 6.4% [IQR, 3.2-11]; p = 0.022).

CONCLUSION

TCRγδ+ T cell assessment accurately diagnoses CD before and after a GFD. Increased TCRγδ+ was maintained in the long term after GFD in CD but not in NCGS. Altogether, this suggests the potential usefulness of this marker for the differential diagnosis of these two entities in patients on a GFD.

Psoriasis, bone and bowel: a comprehensive review and new insights

Psoriasis is a chronic immune-mediated disorder affecting about 2% of the population worldwide which is associated with significant morbidity. The disease usually presents as raised, well-demarcated erythematous plaques with adherent silvery scales. Psoriasis can appear at any age but it has two peaks occurring at 15–20 and 55–60 years of age. It affects males and females equally. Despite the multitude of investigations about psoriasis and even development of drugs with satisfactory results, its pathogenesis is not fully understood yet and its course is unpredictable. Various environmental triggers, e.g., obesity, stress and drugs may induce disease in genetically susceptible patients. Although psoriasis was considered primarily as a disease of the skin, more investigations have been revealed its systemic nature. Psoriatic arthritis (PsA) may complicate up to one-third of cases of psoriasis vulgaris (PV). Also, the association between psoriasis and a variety of other immune-mediated disorders such as inflammatory bowel disease (IBD) and celiac disease (CD) has been confirmed in various studies. Moreover, a growing body of evidences indicates that psoriasis shares some common histological and phenotypical properties with the spectrum of osteoimmunological diseases such as Paget’s disease of bone (PDB). Thus, exploring the common molecular and genetic mechanisms underlying psoriasis and related disorders is of paramount importance for better elucidating disease pathogenesis and designing more targeted treatments.

Efficacy of a gluten-free diet in reducing the widespread pain index and symptom severity scale in patients affected by fibromyalgia

OBJECTIVE

Dietary interventions to improve fibromyalgia (FM) symptoms reported conflicting results. This study aimed to treat FM patients with a gluten-free diet (GFD), alternated with a non-restricted gluten-containing diet, followed by a rechallenge of the GFD.

METHODS

Twenty postmenopausal women with FM and no history of celiac disease participated. A GFD was assigned for 6 months. This was followed by 3 months of a non-restricted gluten-containing diet and then a new GFD for another 6 months. At each visit, the widespread pain index (WPI) and the symptom severity scale (SS) scores were evaluated.

RESULTS

The mean age of the patients enrolled was 53.9±10 years. None of the patients had a diagnosis of irritable bowel disease, although they reported vague gastrointestinal symptoms. After 6 months of a GFD, a statistically significant reduction was observed for the WPI (10.3±1.8 vs 7.7±1.4; p<0.0001) and the SS scale (6.4±1.8 vs 4.15±1.6; p=0.0002). The D percentage reduction of the WPI after 6 months of GFD was -24%±9%, while for the SS scale, it was -36%±21%. The following reintroduction of a gluten-containing diet brought about a statistically significant rise in the absolute SS scale and WPI, as well as a D modification of the WPI (21%±13%) and of the SS scale (74%±90%). The rechallenge of the GFD showed a significant improvement in absolute and D WPI (-24%±7%) and SS (-36%±11%). No modifications to the body mass index were found.

CONCLUSIONS

A GFD improved FM symptoms evaluated with WPI and SS. This was confirmed for the first time, also with a rechallenge of the GFD that followed a non-restricted gluten-containing diet.

Diagnostic management of patients reporting symptoms after wheat ingestion

Many patients report symptoms after wheat ingestion experiencing a wide spectrum of clinical manifestations. Three possible diagnoses have been recognized: celiac disease (CD), wheat allergy (WA), and non-celiac (gluten) wheat sensitivity (NCGS/NCWS). CD is a chronic immune-mediated disease of the small bowel caused by exposure to dietary gluten in genetically predisposed individuals, with a prevalence of approximately 1%. It is characterized by mucosal inflammation and atrophy following exposure to gluten and improvement after gluten withdrawal. Food allergies are immunological responses to a food antigen. WA is the expression of an immunologically mediated process that can be immunoglobulin E (IgE) or non-IgE mediated; its many symptoms include urticaria/angioedema, asthma, rhinitis, and anaphylaxis. NCGS/NCWS is characterized by gastrointestinal and/or extra-intestinal symptoms after ingestion of gluten-containing food in subjects not affected by CD or WA. The aim of this review is to help physicians and nutritionists diagnose the cause of symptoms reported after wheat ingestion, thus avoiding patient frustration, inappropriate testing, and incorrect or missed diagnoses. An algorithm for the diagnostic approach in these patients is provided, to help to diagnose CD, WA, NCGS/NCWS or to identify possible functional disorders as the wheat-sensitive irritable bowel syndrome. A personalized approach, regular follow-up, and the help of a skilled healthcare professional are mandatory for patients with symptoms following wheat ingestion is provided. A gluten-free-diet is often recommended for patients with self-reported gluten/wheat-dependent symptoms; for patients with symptoms similar to those of functional diseases while there is evidence that a low-FODMAP diet could be the first option.

Assessing Hydrolyzed Gluten Content in Dietary Enzyme Supplements Following Fermentation

Partially digested gluten fragments from grains including wheat, rye, spelt and barley are responsible for triggering an inflammatory response in the intestinal tract of Celiac Disease (CD) and Non-Celiac Gluten Sensitive (NCGS) individuals. Fermentation is an effective method to metabolize gluten, with enzymes from bacterial or fungal species being released to help in this process. However, the levels of gluten in commercially available enzymes, including those involved in gluten fermentation, are unknown. In this study we investigated gluten levels in commercially available dietary enzymes combined with assessing their effect on inflammatory response in human cell culture assays. Using antibodies that recognize different gluten epitopes (G12, R5, 2D4, MloBS and Skerritt), we employed ELISA and immunoblotting methodologies to determine gluten content in crude gluten, crude gliadin, pepsin-trypsin digested gluten and a selection of commercially available enzymes. We further investigated the effect of these compounds on inflammatory response in immortalized immune and intestinal human cell lines, as well as in peripheral blood mononuclear cells (PBMCs) from coeliac individuals. All tested supplemental enzyme products reported a gluten concentration that was equivalent to or below 20 parts per million (ppm) as compared with an intact wheat reference standard and a pepsin-trypsin digested standard. Similarly, the inflammatory response to IL-8 and TNF-α inflammatory cytokines in mammalian cell lines and PBMCs from coeliac individuals to the commercial enzymes was not significantly different to 20 ppm of crude gluten, crude gliadin or pepsin-trypsin digested gluten. This combined approach provides insight into the extent of gluten breakdown in the fermentation process and the safety of these products to gluten-sensitive individuals.

Gluten, Inflammation, and Neurodegeneration

Growing evidence supports a potential link between dietary gluten intake and neurodegenerative disease in susceptible populations. Observational data supporting this link are described along with interventional study data evaluating the effects of restricting gluten from the diet in patients with neurologic disorders. Suggested underlying mechanisms between gluten intake and neurodegeneration are discussed.

Self-reported Wheat Sensitivity in Irritable Bowel Syndrome and Healthy Subjects: Prevalence of Celiac Markers and Response to Wheat-free Diet

Background/Aims

Most patients with irritable bowel syndrome (IBS) report food-related aggravation of symptoms. Wheat/gluten is one of the most commonly incriminated. We studied the prevalence of self-reported wheat sensitivity in patients with IBS and in a healthy population from a region in India consuming mixed-cereal diets, correlated it with serological and human leukocyte antigen (HLA) markers of celiac disease, and evaluated the response to a wheat-free diet.

Methods

We surveyed 204 patients with IBS and 400 healthy persons for self-reported wheat sensitivity. Testing for IgA anti-tissue transglutaminase and HLA DQ2 or DQ8 was done in individuals who reported wheat sensitivity. Consenting persons with wheat sensitivity were put on wheat-free diet and monitored for symptom change.

Results

Twenty-three of 204 patients with IBS (11.3%) and none of the healthy subjects self-reported wheat sensitivity. Of 23 patients, 14 (60.9%) were positive for HLA DQ2 or DQ8 and none for anti-tissue transglutaminase antibody. After 6 weeks on wheat-free diet, all 19 participating patients reported clinical improvement; fewer patients had bloating, diarrhea, constipation, and easy fatigue.

Conclusions

Eleven percent of patients with IBS self-reported wheat sensitivity. None of them had positive celiac serology; 60.9% were positive for HLA DQ2 and DQ8, suggesting a possible genetic basis. All of them improved symptomatically on a wheat-free diet.

Could it be gluten? Additional skin conditions associated with celiac disease

Celiac disease is a multifactorial, inflammatory disorder initiated and sustained by the ingestion of gluten. Occurring across a broad population, the intestinal and extraintestinal manifestations of celiac disease are variable in severity and may be nonspecific in presentation. Given that environmental, genetic, and immune factors involved in the pathogenesis of celiac disease that the digestive tract and skin share many characteristics, and with a prevalence of 0.5-1% in most populations, it is reasonable to consider varying presentations of skin conditions that are linked with celiac disease. The association between celiac disease and skin conditions has been discussed earlier, but new studies have emerged suggesting cutaneous involvement in addition to dermatitis herpetiformis. We review the current literature identifying the relationship and potential mechanisms between celiac disease and various skin conditions.

Gynecological Disorders in Patients with Non-celiac Wheat Sensitivity

BACKGROUND

Non-celiac wheat sensitivity (NCWS) most frequently presents clinically with irritable bowel syndrome (IBS)-like symptoms, although many extra-intestinal manifestations have also been attributed to it. No studies to date have evaluated the presence and frequency of gynecological symptoms in NCWS.

AIM

To evaluate the frequency of gynecological disorders in patients with NCWS.

PATIENTS AND METHODS

Sixty-eight women with NCWS were included in the study. A questionnaire investigating gynecological symptoms and recurrent cystitis was administered, and patients reporting symptoms were then examined by specialists. Three control groups were selected: 52 patients with IBS not related to NCWS, 56 patients with celiac disease (CD), and 71 healthy controls.

RESULTS

59% of the patients with NCWS showed gynecological symptoms, a higher frequency than in healthy controls (P = 0.04), IBS controls (P = 0.01) and CD controls (P = 0.02). Menstrual cycle alterations were more frequent in patients with NCWS than in healthy controls (26.5% vs 11.3%; P = 0.03); the patients with NCWS suffered from recurrent vaginitis (16%) and dyspareunia (6%) significantly more frequently than healthy controls. Twenty-nine percent of patients with NCWS reported recurrent cystitis, a finding higher than in the control groups (vs healthy P = 0.0001, vs IBS P = 0.001, vs CD controls P = 0.04). Microbiological examinations were negative in most of the patients with NCWS and recurrent vaginitis or cystitis. During the 1-year follow-up, 46% of patients with menstrual disorders and 36% with recurrent vaginitis reported resolution of symptoms on a wheat-free diet.

CONCLUSIONS

Patients with NCWS showed a significantly higher frequency of gynecological symptoms and recurrent cystitis than patients with IBS.

Coeliac disease and noncoeliac wheat or gluten sensitivity

Coeliac disease (CD) and noncoeliac wheat or gluten sensitivity (NCWS/NCGS) are common gluten-related disorders. Both conditions can present with gastrointestinal and extraintestinal manifestations, which can be a challenge for physicians to discern between. Whilst coeliac serology and histological assessment are required for the diagnosis of CD, there are no clear biomarkers for the diagnosis of NCGS. The management of both conditions is with a gluten-free diet (GFD), although the duration, as well as strictness of adherence to a GFD in NCGS, is unclear. Adherence to a GFD in CD can also be challenging, with recent developments of noninvasive assessments, although histological assessment via duodenal biopsies remains the gold standard. The management of refractory coeliac disease remains particularly challenging, often requiring specialist input. Whilst wheat is noted to be a trigger for symptom generation in NCGS, it is unclear which components of wheat are responsible for symptom generation in this group, with further research required to elucidate the pathophysiology.

Dietary Gluten and Neurodegeneration: A Case for Preclinical Studies

Although celiac disease (CD) is an autoimmune disease that primarily involves the intestinal tract, mounting evidence suggests that a sizeable number of patients exhibit neurological deficits. About 40% of the celiac patients with neurological manifestations have circulating antibodies against neural tissue transglutaminase-6 (tTG6). While early diagnosis and strict adherence to a gluten-free diet (GFD) have been recommended to prevent neurological dysfunction, better therapeutic strategies are needed to improve the overall quality of life. Dysregulation of the microbiota-gut-brain axis, presence of anti-tTG6 antibodies, and epigenetic mechanisms have been implicated in the pathogenesis. It is also possible that circulating or gut-derived extracellular structures and including biomolecular condensates and extracellular vesicles contribute to disease pathogenesis. There are several avenues for shaping the dysregulated gut homeostasis in individuals with CD, non-celiac gluten sensitivity (NCGS) and/or neurodegeneration. In addition to GFD and probiotics, nutraceuticals, such as phyto and synthetic cannabinoids, represent a new approach that could shape the host microbiome towards better prognostic outcomes. Finally, we provide a data-driven rationale for potential future pre-clinical research involving non-human primates (NHPs) to investigate the effect of nutraceuticals, such as phyto and synthetic cannabinoids, either alone or in combination with GFD to prevent/mitigate dietary gluten-induced neurodegeneration.

Nonceliac Gluten Sensitivity—A Masquerading IBS or a Real Phenomenon?

The gluten-free diet has become popular among the public. People who are using this diet have reported symptom relief once gluten has been removed from their diet. Nonceliac gluten sensitivity (NCGS) has emerged as a new diagnosis for those patients who have tested negative for celiac disease. Although there are no diagnostic markers established for NCGS, its symptomatology ranges from gastrointestinal symptoms to neuropsychiatric symptoms. Indeed, some of these symptoms are also seen in patients with irritable bowel syndrome (IBS), such as abdominal pain, bloating, altered bowel movement, diarrhea, and constipation. It is important to add that unlike celiac disease, NGCS has never been associated with any long-term malignancy. We aim to review the recent clinical data available on this topic and address the overlap symptoms between NCGS and IBS. We concluded that despite the overlap symptoms between both diseases, NCGS is a real clinical phenomenon that awaits its own diagnostic clinical criteria and specific laboratory markers. We suggest that patients with gluten sensitivity who are negative for celiac disease should be considered for NCGS.

Pathogenesis of Celiac Disease and Other Gluten Related Disorders in Wheat and Strategies for Mitigating Them

Wheat is a major cereal crop providing energy and nutrients to the billions of people around the world. Gluten is a structural protein in wheat, that is necessary for its dough making properties, but it is responsible for imparting certain intolerances among some individuals, which are part of this review. Most important among these intolerances is celiac disease, that is gluten triggered T-cell mediated autoimmune enteropathy and results in villous atrophy, inflammation and damage to intestinal lining in genetically liable individuals containing human leukocyte antigen DQ2/DQ8 molecules on antigen presenting cells. Celiac disease occurs due to presence of celiac disease eliciting epitopes in gluten, particularly highly immunogenic alpha-gliadins. Another gluten related disorder is non-celiac gluten-sensitivity in which innate immune-response occurs in patients along with gastrointestinal and non-gastrointestinal symptoms, that disappear upon removal of gluten from the diet. In wheat allergy, either IgE or non-IgE mediated immune response occurs in individuals after inhalation or ingestion of wheat. Following a life-long gluten-free diet by celiac disease and non-celiac gluten-sensitivity patients is very challenging as none of wheat cultivar or related species stands safe for consumption. Hence, different molecular biology, genetic engineering, breeding, microbial, enzymatic, and chemical strategies have been worked upon to reduce the celiac disease epitopes and the gluten content in wheat. Currently, only 8.4% of total population is affected by wheat-related issues, while rest of population remains safe and should not remove wheat from the diet, based on false media coverage.

Immunoglobulin G4-related immune responses to common food antigens in patients with ulcerative colitis and Crohn's disease

BACKGROUND/AIMS

It is unclear whether IgG4-related immune responses to food can play a role in the pathogenesis of inflammatory bowel disease (IBD). The aim of the present study was to investigate the serum levels of IgG4 to common food antigens in patients with ulcerative colitis (UC), Crohn's disease (CD), and healthy controls.

MATERIALS AND METHODS

Thirty-six patients with CD (n=12) or UC (n=24) and 36 sex- and age-matched healthy individuals (mean age, 49 years) participated in the study. Serum levels of IgG4 to 90 common food antigens were measured. The number of subjects with positivity, defined by cut-off values ≥0.7 U/mL, was compared.

RESULTS

Serum titers of IgG4 to salmon, onion, shrimp, cuttlefish, eel, millet, gluten, soybean, and coconut in patients with IBD were significantly or tended to be higher than those in the control group. Serum levels of IgG4 to salmon, millet, and onion in patients with CD were significantly or tended to be higher than those in the control group. Serum titers of IgG4 to cuttlefish and onion in patients with UC tended to be higher than those in the control group. The number of subjects with positivity to cod, tuna, mackerel, oat, pea, peanut, and coconut was significantly higher in patients with CD than in healthy controls. The number of subjects with positivity to kiwi and cuttlefish was significantly higher in patients with UC than in controls.

CONCLUSION

Patients with IBD shows higher serum levels of IgG4 to diverse food antigens. Patients with CD present IgG4-related immune reactions to more foods than patients with UC.

A Durum Wheat Variety-Based Product Is Effective in Reducing Symptoms in Patients with Non-Celiac Gluten Sensitivity: A Double-Blind Randomized Cross-Over Trial

Patients with non-celiac gluten sensitivity (NCGS) do not have celiac disease, but their symptoms improve after a gluten-free diet (GFD). However, to date, it is uncertain if gluten or other components of wheat are responsible for these symptoms. The aim of this study was to compare the effects of an organic durum wheat variety with those of standard commercial wheat in patients with known NCGS. We performed a double-blind randomized cross-over trial of 42 patients (mean age 45 years, 8 men) with NCGS diagnosed according to the Salerno criteria and adherence to GFD for at least 12 weeks from screening. Enrolled subjects were randomly assigned to one the following groups of treatment: (A) a two-week diet with Senatore Cappelli wheat variety pasta; (B) a two-week diet with standard commercial pasta. Then, after a two-week washout period on gluten-free diet, each patient crossed over to the other treatment group. Symptoms were assessed through a modified version of the Gastrointestinal Symptom Rating Scale (GSRS), tailored on NCGS. Between April 2018 and July 2018, 42 patients with NCGS were enrolled in the study (70.6% females), and 34 patients completed the study. Patients reported lower overall symptoms scores after eating Senatore Cappelli pasta than standard pasta (p = 0.03) and also significantly lower scores in several specific gastrointestinal and extra-intestinal symptoms after eating Senatore Cappelli pasta than standard pasta, specifically, bloating (p = 0.04), abdominal distention (p = 0.004), eructation (p = 0.01), flatus (p = 0.02), feeling of incomplete evacuation (p = 0.001), dermatitis (p = 0.01), and limb numbness (p = 0.03). In our study, patients with NCGS experienced lower gastrointestinal and extra-intestinal symptom scores after eating the Senatore Cappelli wheat variety than a standard commercial wheat. Should our preliminary results be confirmed by further studies, new dietary alternatives may be available to patients with NCGS, with consequent health, economic, and social benefits.

Abdominal Ultrasound Does Not Reveal Significant Alterations in Patients With Nonceliac Wheat Sensitivity

GOALS

The goal of this study was (A) to evaluate abdominal ultrasound signs in nonceliac wheat sensitivity (NCWS) patients for features useful in diagnosis and (B) to compare these aspects with those of celiac patients to assess whether ultrasound can be useful in the differential diagnosis between NCWS and celiac disease (CD).

BACKGROUND

NCWS diagnosis is difficult as no biomarkers of this condition have as yet been identified. In CD ultrasound aspects have been identified that have a good diagnostic accuracy.

STUDY

We prospectively recruited 45 NCWS patients (11 males, 34 females; mean age 35.7 y). Three control groups were included: (A) 99 age-matched CD patients; (B) 18 patients with seronegative CD; (C) 50 patients with irritable bowel syndrome (IBS) who did not improve on a wheat-free diet. NCWS diagnosis was confirmed on the basis of an elimination diet and double-blind placebo-controlled (DBPC) challenge. Ultrasound sign investigation included: dilatation of the small bowel loops, thickening of the small bowel wall, hyperperistalsis, enlarged mesenteric lymph nodes, ascites, hyposplenism, altered diameter of the portal vein.

RESULTS

NCWS patients showed a low frequency of pathologic ultrasound findings. Dilated or thickened loops appeared more often in CD patients than in NCWS patients (88.8% vs. 20%; P<0.0001). These US signs were significantly more frequent in seronegative CD than in NCWS patients (both P<0.0001), whereas no difference was found between NCWS patients and IBS controls.

CONCLUSIONS

In NCWS patients' ultrasound does not show a characteristic pattern which could be helpful for diagnosis. However, US can be useful to differentiate between NCWS and CD patients and especially those with seronegative CD. (ClinicalTrials.gov NCT03017274).

Gluten-Free Diet and Its 'Cousins' in Irritable Bowel Syndrome

Functional disorders are common, with irritable bowel syndrome (IBS) being the commonest and most extensively evaluated functional bowel disorder. It is therefore paramount that effective therapies are available to treat this common condition. Diet appears to play a pivotal role in symptom generation in IBS, with a recent interest in the role of dietary therapies in IBS. Over the last decade, there has been a substantial increase in awareness of the gluten-free diet (GFD), with a recent focus of the role of a GFD in IBS. There appears to be emerging evidence for the use of a GFD in IBS, with studies demonstrating the induction of symptoms following gluten in patients with IBS. However, there are questions with regards to which components of wheat lead to symptom generation, as well as the effect of a GFD on nutritional status, gut microbiota and long-term outcomes. Further studies are required, although the design of dietary studies remain challenging. The implementation of a GFD should be performed by a dietitian with a specialist interest in IBS, which could be achieved via the delivery of group sessions.

Mood Disorders and Gluten: It's Not All in Your Mind! A Systematic Review with Meta-Analysis

Gluten elimination may represent an effective treatment strategy for mood disorders in individuals with gluten-related disorders. However, the directionality of the relationship remains unclear. We performed a systematic review of prospective studies for effects of gluten on mood symptoms in patients with or without gluten-related disorders. Six electronic databases (CINAHL, PsycINFO, Medline, Web of Science, Scopus and Cochrane Library) were searched, from inception to 8 August 2018, for prospective studies published in English. Meta-analyses with random-effects were performed. Three randomised-controlled trials and 10 longitudinal studies comprising 1139 participants fit the inclusion criteria. A gluten-free diet (GFD) significantly improved pooled depressive symptom scores in GFD-treated patients (Standardised Mean Difference (SMD) -0.37, 95% confidence interval (CI) -0.55 to -0.20; p < 0.0001), with no difference in mean scores between patients and healthy controls after one year (SMD 0.01, 95% CI -0.18 to 0.20, p = 0.94). There was a tendency towards worsening symptoms for non-coeliac gluten sensitive patients during a blinded gluten challenge vs. placebo (SMD 0.21, 95% CI -0.58 to 0.15; p = 0.25). Our review supports the association between mood disorders and gluten intake in susceptible individuals. The effects of a GFD on mood in subjects without gluten-related disorders should be considered in future research.

Breaking bread!

Humankind has existed for 2·5 million years but only in the past 10 000 years have we been exposed to wheat. Therefore, it could be considered that wheat (gluten) is a novel introduction to humankind's diet! Prior to 1939, the rationing system had already been devised. This led to an imperative to try to increase agricultural production. Thus, it was agreed in 1941 that there was a need to establish a Nutrition Society. The very roots of the Society were geared towards necessarily increasing the production of wheat. This goal was achieved and by the end of the 20th century, global wheat output had expanded by 5-fold. Perhaps, as a result, the epidemiology of coeliac disease (CD) or gluten sensitive enteropathy has changed. CD now affects 1 % or more of all adults. Despite this, delays in diagnosis are common, for every adult patient diagnosed approximately three–four cases are undetected. This review explores humankind's relationship with gluten, wheat chemistry, the rising prevalence of modern CD and the new entity of non-coeliac gluten or wheat sensitivity. The nutritional interventions of a low fermentable oligo-, di- and mono-saccharides and polyols diet and gluten-free diet (GFD) for irritable bowel syndrome and the evidence to support this approach (including our own published work) are also reviewed. There appears to be a rising interest in the GFD as a ‘lifestyler’, ‘free from’ or ‘clean eater’ choice, causing concern. Restrictive diets may lead to potential nutritional implications, with long-term effects requiring further exploration.

The Significance of Low Titre Antigliadin Antibodies in the Diagnosis of Gluten Ataxia

Background: Patients with gluten ataxia (GA) without enteropathy have lower levels of antigliadin antibodies (AGA) compared to patients with coeliac disease (CD). Magnetic Resonance Spectroscopy (NAA/Cr area ratio) of the cerebellum improves in patients with GA following a strict gluten-free diet (GFD). This is associated with clinical improvement. We present our experience of the effect of a GFD in patients with ataxia and low levels of AGA antibodies measured by a commercial assay. Methods: Consecutive patients with ataxia and serum AGA levels below the positive cut-off for CD but above a re-defined cut-off in the context of GA underwent MR spectroscopy at baseline and after a GFD. Results: Twenty-one consecutive patients with GA were included. Ten were on a strict GFD with elimination of AGA, 5 were on a GFD but continued to have AGA, and 6 patients did not go on a GFD. The NAA/Cr area ratio from the cerebellar vermis increased in all patients on a strict GFD, increased in only 1 out of 5 (20%) patients on a GFD with persisting circulating AGA, and decreased in all patients not on a GFD. Conclusion: Patients with ataxia and low titres of AGA benefit from a strict GFD. The results suggest an urgent need to redefine the serological cut-off for circulating AGA in diagnosing GA.

Office-Based Point of Care Testing (IgA/IgG-Deamidated Gliadin Peptide) for Celiac Disease

OBJECTIVES

Celiac disease (CD) is common yet under-detected. A point of care test (POCT) may improve CD detection. We aimed to assess the diagnostic performance of an IgA/IgG-deamidated gliadin peptide (DGP)-based POCT for CD detection, patient acceptability, and inter-observer variability of the POCT results.

METHODS

From 2013-2017, we prospectively recruited patients referred to secondary care with gastrointestinal symptoms, anemia and/or weight loss (group 1); and patients with self-reported gluten sensitivity with unknown CD status (group 2). All patients had concurrent POCT, IgA-tissue transglutaminase (IgA-TTG), IgA-endomysial antibodies (IgA-EMA), total IgA levels, and duodenal biopsies. Five hundred patients completed acceptability questionnaires, and inter-observer variability of the POCT results was compared among five clinical staff for 400 cases.

RESULTS

Group 1: 1000 patients, 58.5% female, age 16-91, median age 57. Forty-one patients (4.1%) were diagnosed with CD. The sensitivities of the POCT, IgA-TTG, and IgA-EMA were 82.9, 78.1, and 70.7%; the specificities were 85.4, 96.3, and 99.8%. Group 2: 61 patients, 83% female; age 17-73, median age 35. The POCT had 100% sensitivity and negative predictive value in detecting CD in group 2. Most patients preferred the POCT to venepuncture (90.4% vs. 2.8%). There was good inter-observer agreement on the POCT results with a Fleiss Kappa coefficient of 0.895.

CONCLUSIONS

The POCT had comparable sensitivities to serology, and correctly identified all CD cases in a gluten sensitive cohort. However, its low specificity may increase unnecessary investigations. Despite its advantage of convenience and rapid results, it may not add significant value to case finding in an office-based setting.

The Global Phenomenon of Self-Reported Wheat Sensitivity

Celiac disease affects about 1% of the population and is treated with a gluten-free diet. However, the last decade has seen a huge rise in individuals self-reporting wheat sensitivity, and consuming a gluten-free diet, despite not having a doctor-diagnosis of celiac disease. A recent flurry of observational studies from across the globe suggests that approximately 10% of the population is self-reporting wheat sensitivity. They describe a constellation of intestinal and extra-intestinal symptoms attributed to ingestion of gluten-based products. This phenomenon poses a significant challenge to clinicians with regards to adequately excluding celiac disease, identifying the culprit agent, understanding the pathophysiology, and providing safe aftercare.

Gastroenterology and Neurology

PURPOSE OF REVIEW

Just as gastrointestinal dysfunction may develop in the setting of neurologic disease, neurologic dysfunction may become evident in the setting of gastrointestinal disease. This article describes the range of neurologic features that have been described in three primary gastrointestinal diseases: celiac disease and gluten-related disorders, inflammatory bowel disease, and Whipple disease. Particular emphasis is placed on the controversial and evolving clinical picture of neurologic dysfunction in disorders of gluten sensitivity.

RECENT FINDINGS

Gluten-related disorders, including both the traditional autoimmune-based celiac disease and the more recently recognized nonautoimmune, nonallergic gluten sensitivity, have been the source of much attention in both medical and lay publications. The possible association between Crohn disease and neurologic disorders also is receiving attention. The recognition that, although Whipple disease is an exceedingly rare disorder, a surprising percentage of the population may be asymptomatic stool carriers of the causative organism makes it important to always be cognizant of the disorder.

SUMMARY

The range of neurologic dysfunction in gastrointestinal diseases is broad and spans the spectrum from peripheral to central processes. Peripheral neuropathy, myopathy, myelopathy, cerebrovascular events, epilepsy, encephalopathy, and cerebellar dysfunction have all been described. Neurologists should be aware of the possibility that an underlying gastrointestinal disease process may be present in and responsible for the neurologic dysfunction that has prompted referral of an individual for evaluation.

Efficacy of a Gluten-Free Diet in the Gilles de la Tourette Syndrome: A Pilot Study

The Gilles de la Tourette syndrome (GTS) and Non-Coeliac Gluten Sensitivity (NCGS) may be associated. We analyse the efficacy of a gluten-free diet (GFD) in 29 patients with GTS (23 children; six adults) in a prospective pilot study. All of them followed a GFD for one year. The Yale Global Tics Severity Scale (YGTSS), the Yale-Brown Obsessive-Compulsive Scale—Self Report (Y-BOCS) or the Children’s Yale-Brown Obsessive-Compulsive Scale—Self Report (CY-BOCS), and the Cavanna’s Quality of Life Questionnaire applied to GTS (GTS-QOL) were compared before and after the GFD; 74% of children and 50% of adults were males, not significant (NS). At the beginning of the study, 69% of children and 100% of adults had associated obsessive-compulsive disorder (OCD) (NS). At baseline, the YGTSS scores were 55.0 ± 17.5 (children) and 55.8 ± 19.8 (adults) (NS), the Y-BOCS/CY-BOCS scores were 15.3, (standard deviation (SD) = 12.3) (children) and 26.8 (9.2) (adults) (p = 0.043), and the GTS-QOL scores were 42.8 ± 18.5 (children) and 64 ± 7.9 (adults) (p = 0.000). NCGS was frequent in both groups, with headaches reported by 47.0% of children and 83.6% of adults (p = 0.001). After one year on a GFD there was a marked reduction in measures of tics (YGTSS) (p = 0.001), and the intensity and frequency of OCD (Y-BOCS/CY-BOCS) (p = 0.001), along with improved generic quality of life (p = 0.001) in children and adults. In conclusion, a GFD maintained for one year in GTS patients led to a marked reduction in tics and OCD both in children and adults.

Cognitive impairment in celiac disease and non-celiac gluten sensitivity: review of literature on the main cognitive impairments, the imaging and the effect of gluten free diet

Celiac disease (CD) and non celiac gluten sensitivity (NCGS) can be responsible for neurological complications such as ataxia and peripheral neuropathies but also cognitive impairment. This cognitive involvement is variable in its expression, its duration and its prognosis ranging from transient and reversible subtle involvement to dementia itself. Through this article, we tried to achieve a review of the literature to better understand this topic. Several mechanisms were proposed to explain the deleterious influence of gluten-related pathologies on cognitive functions: nutritional deficiencies, elevation of circulating cytokine levels due to systemic inflammation, low brain serotonin levels… Several types of dementia such as Alzheimer dementia, vascular dementia, frontotemporal dementia were reported in association with CD. Memory disorder, acalculia, inattention, visuospatial deficits and executive dysfunction must be sought systematically by a neuropsychological assessment in patients with CD or NCGS. As far as the cognitive impairment is concerned, there is no pathognomonic radiological lesion. Concerning therapeutic management; although its effect is controversial, gluten free diet should be introduced, as early as possible, because of its potentially protective effect.

Dietary therapies for functional bowel symptoms: Recent advances, challenges, and future directions

BACKGROUND

Functional gastrointestinal symptoms in irritable bowel syndrome (IBS) and quiescent inflammatory bowel disease (IBD) cause significant morbidity and a reduction in quality of life. Multiple dietary therapies are now available to treat these symptoms, but supporting evidence for many is limited. In addition to a further need for studies demonstrating efficacy and mechanism of action of dietary therapies, the risk of nutritional inadequacy, alterations to the microbiome and changes in quality of life are key concerns requiring elucidation. Identifying predictors of response to dietary therapy is an important goal as management could be tailored to the individual to target specific dietary components, and thereby reduce the level of dietary restriction necessary.

PURPOSE

This review discusses the available dietary therapies to treat symptoms in patients with IBS and patients with quiescent IBD suffering from IBS symptoms, with the aim to understand where current dietary evidence lies and how to move forward in dietary research in this field.

The Overlapping Area of Non-Celiac Gluten Sensitivity (NCGS) and Wheat-Sensitive Irritable Bowel Syndrome (IBS): An Update

Gluten-related disorders have recently been reclassified with an emerging scientific literature supporting the concept of non-celiac gluten sensitivity (NCGS). New research has specifically addressed prevalence, immune mechanisms, the recognition of non-immunoglobulin E (non-IgE) wheat allergy and overlap of NCGS with irritable bowel syndrome (IBS)-type symptoms. This review article will provide clinicians with an update that directly impacts on the management of a subgroup of their IBS patients whose symptoms are triggered by wheat ingestion.

Celiac Disease and Gluten Sensitivity

Celiac disease is an immune-mediated enteropathy triggered by gluten that affects genetically predisposed individuals, typically causing intestinal symptoms and malabsorption. Diagnosis requires stepwise evaluation with anti-tissue transglutaminase IgA and histologic analysis of the small bowel. Strict adherence to a gluten-free diet is the primary treatment. Patients with symptoms thought to be related to gluten but without evidence of celiac disease are difficult to diagnose and treat. Consider first advising general nutritional improvements. If symptoms persist, involve a trained dietitian for restrictive diets and consider evaluation for small intestinal bacterial overgrowth or other treatments for irritable bowel syndrome.

Gluten-related disorders: certainties, questions and doubts

In the last decade, the ingestion of gluten, a heterogeneous complex of proteins present in wheat, rice, barley and probably in oats, has been associated with clinical disorders, such as celiac disease, wheat allergy and recently to non-celiac gluten sensitivity or wheat intolerance syndrome. Gluten-related disorders, which are becoming epidemiologically relevant with an estimated global prevalence of about 5%, require the exclusion of gluten from the diet. For the past 5 years, an important shift in the availability of gluten-free products, together with increased consumption in the general population, has been recorded and is estimated to be about 12-25%. Many people follow a self-prescribed gluten-free diet, despite the fact that the majority have not first been previously excluded, or confirmed, as having gluten disorders. They rely on claims that a gluten-free diet improves general health. In this review, we provide an overview of the clinical disorders related to gluten or wheat ingestion, pointing out the current certainties, open questions, possible answers and several doubts in the management of these conditions. KEY MESSAGE Incidence of gluten-related disorders is increased in the last decade and self-diagnosis is frequent with inappropriate starting of a gluten-free diet. Gluten and wheat are considered as the most important triggers to coeliac disease, wheat allergy and non-celiac gluten sensitivity. Pediatricians, allergologist and gastroenterologist are involved in the management of these conditions and appropriate diagnostic protocols are required.

Non-celiac gluten sensitivity: All wheat attack is not celiac

Currently, 1% of the United States population holds a diagnosis for celiac disease (CD), however, a more recently recognized and possibly related condition, "non-celiac gluten sensitivity" (NCGS) has been suggested to affect up to 6% of the United States public. While reliable clinical tests for CD exist, diagnosing individuals affected by NCGS is still complicated by the lack of reliable biomarkers and reliance upon a broad set of intestinal and extra intestinal symptoms possibly provoked by gluten. NCGS has been proposed to exhibit an innate immune response activated by gluten and several other wheat proteins. At present, an enormous food industry has developed to supply gluten-free products (GFP) with GFP sales in 2014 approaching $1 billion, with estimations projecting sales to reach $2 billion in the year 2020. The enormous demand for GFP also reflects a popular misconception among consumers that gluten avoidance is part of a healthy lifestyle choice. Features of NCGS and other gluten related disorders (e.g., irritable bowel syndrome) call for a review of current distinctive diagnostic criteria that distinguish each, and identification of biomarkers selective or specific for NCGS. The aim of this paper is to review our current understanding of NCGS, highlighting the remaining challenges and questions which may improve its diagnosis and treatment.

Contact Dermatitis Due to Nickel Allergy in Patients Suffering from Non-Celiac Wheat Sensitivity

Background: Non-celiac wheat sensitivity (NCWS) is a new clinical entity in the world of gluten-related diseases. Nickel, the most frequent cause of contact allergy, can be found in wheat and results in systemic nickel allergy syndrome and mimics irritable bowel syndrome (IBS). Objective: To evaluate the frequency of contact dermatitis due to nickel allergy in NCWS patients diagnosed by a double-blind placebo-controlled (DBPC) challenge, and to identify the characteristics of NCWS patients with nickel allergy. Methods: We performed a prospective study of 60 patients (54 females, 6 males; mean age 34.1 ± 8.1 years) diagnosed with NCWS from December 2014 to November 2016; 80 age- and sex-matched subjects with functional gastrointestinal symptoms served as controls. Patients reporting contact dermatitis related to nickel-containing objects underwent nickel patch test (Clinicaltrials.gov registration number: NCT02750735). Results: Six out of sixty patients (10%) with NCWS suffered from contact dermatitis and nickel allergy and this frequency was statistically higher (p = 0.04) than observed in the control group (5%). The main clinical characteristic of NCWS patients with nickel allergy was a higher frequency of cutaneous symptoms after wheat ingestion compared to NCWS patients who did not suffer from nickel allergy (p < 0.0001). Conclusions: Contact dermatitis and nickel allergy are more frequent in NCWS patients than in subjects with functional gastrointestinal disorders; furthermore, these patients had a very high frequency of cutaneous manifestations after wheat ingestion. Nickel allergy should be evaluated in NCWS patients who have cutaneous manifestations after wheat ingestion.

Intraepithelial lymphocytes, scores, mimickers and challenges in diagnosing gluten-sensitive enteropathy (celiac disease)

The upper digestive tract is routinely scoped for several causes of malabsorption, and the number of duodenal biopsy specimens has increased notably in the last 10 years. Gluten-sensitive enteropathy (GSE) is an autoimmune disease, which shows an increasing prevalence worldwide and requires a joint clinico-pathological approach. The classical histopathology of GSE with partial or total villous blunting is well recognized, but the classification of GSE is not straightforward. Moreover, several mimickers of GSE with intraepithelial lymphocytosis have been identified in the last 20 years, with drug interactions and medical comorbidities adding to the conundrum. In this review, we report on the normal duodenal mucosa, the clinical presentation and laboratory diagnosis of GSE, the duodenal intraepithelial lymphocytes and immunophenotype of GSE-associated lymphocytes, the GSE mimickers, the differences "across oceans" among guidelines in diagnosing GSE, and the use of a synoptic report for reporting duodenal biopsies in both children and adults in the 21st century.

Properties of Gluten Intolerance: Gluten Structure, Evolution, Pathogenicity and Detoxification Capabilities

Theterm gluten intolerance may refer to three types of human disorders: autoimmune celiac disease (CD), allergy to wheat and non-celiac gluten sensitivity (NCGS). Gluten is a mixture of prolamin proteins present mostly in wheat, but also in barley, rye and oat. Gluten can be subdivided into three major groups: S-rich, S-poor and high molecular weight proteins. Prolamins within the groups possess similar structures and properties. All gluten proteins are evolutionarily connected and share the same ancestral origin. Gluten proteins are highly resistant to hydrolysis mediated by proteases of the human gastrointestinal tract. It results in emergence of pathogenic peptides, which cause CD and allergy in genetically predisposed people. There is a hierarchy of peptide toxicity and peptide recognition by T cells. Nowadays, there are several ways to detoxify gluten peptides: the most common is gluten-free diet (GFD), which has proved its effectiveness; prevention programs, enzymatic therapy, correction of gluten pathogenicity pathways and genetically modified grains with reduced immunotoxicity. A deep understanding of gluten intolerance underlying mechanisms and detailed knowledge of gluten properties may lead to the emergence of novel effective approaches for treatment of gluten-related disorders.

Modern Management of Irritable Bowel Syndrome: More Than Motility

In the treatment of irritable bowel syndrome (IBS), loperamide seems efficacious for diarrhea and ispaghula for constipation, while musculotropic spasmolytics may relieve abdominal pain. Antidepressants were found to be efficacious for abdominal pain, but their tolerance may be problematic and the therapeutic effect varied largely between trials. While meta-analyses suggest efficacy of probiotics as a group, the quality of the trials is often suboptimal and there is large variability. Lubiprostone, a chloride channel activator, and linaclotide, a guanylyl cyclase-C agonist, showed favorable effects on multiple symptoms in IBS with constipation. For IBS with diarrhea (IBS-D), the 5-HT3 receptor antagonist ramosetron showed efficacy in men and women, but is currently only approved in Japan. A multicenter study with the anti-emetic 5-HT3 receptor antagonist ondansetron showed efficacy on stool pattern in IBS-D. The poorly absorbable antibiotic rifaximin and eluxadoline, a mu opioid receptor agonist and delta antagonist, both showed efficacy in phase III trials in IBS-D and were approved by the FDA. Eluxadoline was associated with increased occurrence of sphincter of Oddi spasm and biliary pancreatitis. The non-pharmacological treatment of IBS, with dietary interventions (mainly gluten elimination and low FODMAP (fructose, oligo-, di-, monosaccharides and polyols)) has received a lot of attention lately. While responder rates vary across studies, perhaps based on regional variations in dietary intake of FODMAPs, the dietary approach seems to have acquired recognition as a valid therapeutic alternative. Long-term studies and comparative studies with pharmacotherapy, as well as elucidation of the underlying mechanisms of action, are needed.

British Dietetic Association systematic review and evidence-based practice guidelines for the dietary management of irritable bowel syndrome in adults (2016 update)

BACKGROUND

The first British Dietetic Association (BDA) guidelines for the dietary management of irritable bowel syndrome (IBS) in adults were published in 2012. Subsequently, there has been a wealth of new research. The aim of this work was to systematically review the evidence for the role of diet in the management of IBS and to update the guidelines.

METHODS

Twelve questions relating to diet and IBS were defined based on review of the previous guideline questions, current evidence and clinical practice. Chosen topics were on healthy eating and lifestyle (alcohol, caffeine, spicy food, elimination diets, fat and fluid intakes and dietary habits), milk and dairy, dietary fibre, fermentable carbohydrates, gluten, probiotics and elimination diets/food hypersensitivity. Data sources were CINAHL, Cochrane Register of Controlled Trials, Embase, Medline, Scopus and Web of Science up to October 2015. Studies were assessed independently in duplicate using risk of bias tools specific to each included study based on inclusion and exclusion criteria for each question. National Health and Medical Research Council grading evidence levels were used to develop evidence statements and recommendations, in accordance with Practice-based Evidence in Nutrition Global protocol used by the BDA.

RESULTS

Eighty-six studies were critically appraised to generate 46 evidence statements, 15 clinical recommendations and four research recommendations. The IBS dietary algorithm was simplified to first-line (healthy eating, provided by any healthcare professional) and second-line [low FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) to be provided by dietitian] dietary advice.

CONCLUSIONS

These guidelines provide updated comprehensive evidence-based details to achieve the successful dietary management of IBS in adults.

Food, nutrients and nutraceuticals affecting the course of inflammatory bowel disease

Inflammatory bowel diseases (ulcerative colitis; Crohn's disease) are debilitating relapsing inflammatory disorders affecting the gastrointestinal tract, with deleterious effect on quality of life, and increasing incidence and prevalence. Mucosal inflammation, due to altered microbiota, increased intestinal permeability and immune system dysfunction underlies the symptoms and may be caused in susceptible individuals by different factors (or a combination of them), including dietary habits and components. In this review we describe the influence of the Western diet, obesity, and different nutraceuticals/functional foods (bioactive peptides, phytochemicals, omega 3-polyunsaturated fatty acids, vitamin D, probiotics and prebiotics) on the course of IBD, and provide some hints that could be useful for nutritional guidance. Hopefully, research will soon offer enough reliable data to slow down the spread of the disease and to make diet a cornerstone in IBD therapy.

Efficacy of a Gluten-Free Diet in Subjects With Irritable Bowel Syndrome-Diarrhea Unaware of Their HLA-DQ2/8 Genotype

BACKGROUND & AIMS

A gluten-containing diet alters bowel barrier function in patients with irritable bowel syndrome with diarrhea (IBS-D), particularly those who are positive for HLA allele DQ2/8. We studied the effects of a gluten-free diet (GFD) in patients with IBS-D who have not previously considered the effects of gluten in their diet and were unaware of their HLA-DQ2/8 genotype.

METHODS

We performed a prospective study of 41 patients with IBS-D (20 HLA-DQ2/8-positive and 21 HLA-DQ2/8-negative) at the Royal Hallamshire Hospital in Sheffield, United Kingdom, from September 2012 through July 2015. All subjects were placed on a 6-week GFD following evaluation by a dietician. Subjects completed validated questionnaires at baseline and Week 6 of the GFD. The primary endpoint was mean change in IBS Symptom Severity Score; a 50-point reduction was considered to indicate a clinical response. Secondary endpoints were changes in hospital anxiety and depression score, fatigue impact score, and Short Form-36 results. Clinical responders who chose to continue a GFD after the study period were evaluated on average 18 months later to assess diet durability, symptom scores, and anthropometric and biochemical status.

RESULTS

A 6-week GFD reduced IBS Symptom Severity Score by ≥50 points in 29 patients overall (71%). The mean total IBS Symptom Severity Score decreased from 286 before the diet to 131 points after 6 weeks on the diet (P < .001); the reduction was similar in each HLA-DQ group. However, HLA-DQ2/8-negative subjects had a greater reduction in abdominal distention (P = .04). Both groups had marked mean improvements in hospital anxiety and depression scores, fatigue impact score, and Short Form-36 results, although HLA-DQ2/8-positive subjects had a greater reduction in depression score and increase in vitality score than HLA-DQ2/8-negative subjects (P = .02 and P = .03, respectively). Twenty-one of the 29 subjects with a clinical response (72%) planned to continue the GFD long term; 18 months after the study they were still on a GFD, with maintained symptom reductions, and demonstrated similar anthropometric and biochemical features compared with baseline.

CONCLUSIONS

A dietitian-led GFD provided sustained benefit to patients with IBS-D. The symptoms that improved differed in magnitude according to HLA-DQ status. Clinical trials.gov no: NCT02528929.

Neurological Dysfunction in Coeliac Disease and Non-Coeliac Gluten Sensitivity

OBJECTIVES

Non-coeliac gluten sensitivity (NCGS) refers to patients with primarily gastrointestinal symptoms without enteropathy that symptomatically benefit from gluten-free diet (GFD). Little is known about its pathophysiology, propensity to neurological manifestations, and if these differ from patients with coeliac disease (CD). We investigated the clinical and immunological characteristics of patients presenting with neurological manifestations with CD and those with NCGS.

METHODS

We compared clinical, neurophysiological, and imaging data of patients with CD and NCGS presenting with neurological dysfunction assessed and followed up regularly over a period of 20 years.

RESULTS

Out of 700 patients, 562 were included. Exclusion criteria included no bowel biopsy to confirm CD, no HLA type available, and failure to adhere to GFD. All patients presented with neurological dysfunction and had circulating anti-gliadin antibodies. Out of 562 patients, 228 (41%) had evidence of enteropathy (Group 1, CD) and 334 (59%) did not (Group 2, NCGS). The most common neurological manifestations were cerebellar ataxia, peripheral neuropathy, and encephalopathy. There was a greater proportion of patients with encephalopathy in Group 1 and with a greater proportion of neuropathy in Group 2. The severity of ataxia did not differ between the two groups. Patients in Group 1 had more severe neuropathy. All patients from both groups responded to gluten-free diet. Anti-tissue transglutaminase (TG2) antibodies were found in 91% of patients in Group 1 and in 29% of patients in Group 2. Comparison between those patients in Group 2 with HLA-DQ2/DQ8 and those without as well as those with positive TG2 compared with those with negative TG2 antibodies identified no differences within these subgroups. Serological positivity for TG6 antibodies was similar in the two groups (67 and 60%).

CONCLUSIONS

The neurological manifestations of CD and NCGS are similar and equally responsive to a GFD suggestive of common pathophysiological mechanisms.