Spectrum of gluten-related disorders: consensus on new nomenclature and classification

A combined biochemical, biophysical and immunological approach towards the identification of celiac disease-specific wheat antigens

Celiac disease (CD) is an inflammatory affliction of the small bowel caused by an immunological hypersensitivity to ingested wheat antigens affecting almost 1 % of the population. The gliadin fraction of wheat has been shown to contain the pathogenic antigens which react with antibodies and T cells. However, there is only limited knowledge regarding the precise nature of the wheat antigens recognized by IgA antibodies from CD patients and diagnostic tests based on the gliadin fraction have been demonstrated to give frequently false positive results. The aim of this study was the characterization of wheat antigens specifically recognized by IgA antibodies of CD patients. We developed a combined biochemical, biophysical, and immunological approach for the identification of celiac disease-specific wheat antigens. It is based on sub-fractionation of the wheat gliadin fraction using two ion exchange chromatography steps, the localization of CD-specific antigens by immunoblotting with IgA antibodies from CD patients, subsequent digestion followed by electro spray ionization-liquid chromatography/mass spectrometry (LC-ESI-MS/MS) and N-terminal sequencing by Edman degradation. Through the sub-fractionation procedure it was possible to separate CD-specific IgA-reactive wheat antigens from other wheat antigens which were also recognized by IgA antibodies of individuals without CD or by CD patients on gluten-free diet. Analysis by LC-ESI-MS/MS and N-terminal sequencing of the sub-fractions and the proteins specifically recognized by CD patients identified certain γ-gliadins with molecular mass of 37,000 and 45,000 as CD-specific wheat antigens. The CD-specific γ-gliadins with the molecular mass of 37,000 and 45,000 should be useful to study pathomechanisms of the disease and to improve the specificity of diagnostic tests for CD.

Use of fungal proteases and selected sourdough lactic acid bacteria for making wheat bread with an intermediate content of gluten

This study was aimed at combining the highest degradation of gluten during wheat flour fermentation with good structural and sensory features of the related bread. As estimated by R5-ELISA, the degree of degradation of immune reactive gluten was ca. 28%. Two-dimensional electrophoresis and RP-FPLC analyses showed marked variations of the protein fractions compared to the untreated flour. The comparison was also extended to in vitro effect of the peptic/tryptic-digests towards K562 and T84 cells. The flour with the intermediate content of gluten (ICG) was used for bread making, and compared to whole gluten (WG) bread. The chemical, structural and sensory features of the ICG bread approached those of the bread made with WG flour. The protein digestibility of the ICG bread was higher than that from WG flour. Also the nutritional quality, as estimated by different indexes, was the highest for ICG bread.

Impact of coexistent celiac disease on phenotype and natural history of inflammatory bowel diseases

OBJECTIVES

Inflammatory bowel disease (IBD) and celiac disease are the two most common immune-mediated gastrointestinal diseases. There is limited knowledge regarding the course of IBD in those with coexisting celiac disease. We conducted this study to determine whether patients with coexisting celiac disease present a unique phenotype of IBD and to examine the frequency of co-occurrence of celiac disease and IBD in comparison with other autoimmune disorders.

METHODS

This was a case-control study performed at two tertiary referral centers. Cases comprised of patients with known diagnoses of celiac disease and IBD. Two random IBD controls without celiac disease were selected for each case after matching for IBD type. Disease phenotype and natural history for both Crohn's disease (CD) and ulcerative colitis (UC) were noted from medical record review, and were compared between IBD patients with and without celiac disease.

RESULTS

We identified a total of 51 patients with IBD (22 UC, 1 indeterminate colitis, 28 CD) and celiac disease. There was no significant difference in the age, gender, or ethnicity between celiac-IBD and controls. Pancolitis was more common in celiac-UC patients as compared with controls (odds ratio (OR) 3.30, 95% confidence interval (CI) 1.05-21.50). There was also a trend toward increased use of immunomodulators (IMMs) among celiac-UC patients than in non-celiac UC controls (OR 2.83, 95% CI 0.95-8.48). No phenotypic differences were found in celiac-CD patients. There were no significant differences in IBD-related medication usage, hospitalizations, or surgeries.

CONCLUSIONS

Patients with UC and celiac disease were more likely to have pancolitis and had a trend toward greater use of IMMs. Coexisting celiac disease did not influence natural history of CD.

Reduced mortality in dermatitis herpetiformis: a population-based study of 476 patients

BACKGROUND

Dermatitis herpetiformis (DH) is an extra-intestinal manifestation of coeliac disease and most patients adhere to a life-long gluten free diet (GFD). Increased mortality rates have been reported in coeliac disease but knowledge in DH is scanty.

OBJECTIVES

To survey the mortality rate and causes of death in a large cohort of patients with DH.

MATERIAL AND METHODS

Patients with DH (n = 476 consecutive patients) diagnosed from 1970 onwards at the Tampere University Hospital were analysed for causes of death during 1971-2010. A questionnaire survey on key aspects of health behaviour was performed in patients with DH and comparisons were made with the Finnish population.

RESULTS

The total number of deaths during 9079 person years followed up was 77 whereas 110 were expected. The standardized mortality rate (SMR) for all causes of death was significantly reduced, being 0·70 (95% CI 0·55-0·87), and similar in both sexes. The SMR was equal in the patients with DH with (0·73) and without (0·77) small bowel villous atrophy. The SMR was significantly reduced (0·38) for deaths due to cerebrovascular diseases. The SMR due to lymphoproliferative malignancies was significantly increased (6·86) in the first 5 years of follow-up but not thereafter. The questionnaire survey documented that 97·7% of the patients with DH adhered to a GFD. The patients reported significantly less hypercholesterolaemia and there were fewer current and past smokers compared with the age- and sex-matched control population.

CONCLUSIONS

The present long-term follow-up study of DH documented significantly reduced all-cause and cerebrovascular disease mortality. Strict adherence to a GFD, less smoking and hypercholesterolaemia may play a role in the observed health benefit.

How the sourdough may affect the functional features of leavened baked goods

Sourdough fermentation is one of the oldest food biotechnologies, which has been studied and recently rediscovered for its effect on the sensory, structural, nutritional and shelf life properties of leavened baked goods. Acidification, proteolysis and activation of a number of enzymes as well as the synthesis of microbial metabolites cause several changes during sourdough fermentation, which affect the dough and baked good matrix, and influence the nutritional/functional quality. Currently, the literature is particularly rich of results, which show how the sourdough fermentation may affect the functional features of leavened baked goods. In the form of pre-treating raw materials, fermentation through sourdough may stabilize or to increase the functional value of bran fractions and wheat germ. Sourdough fermentation may decrease the glycaemic response of baked goods, improve the properties and bioavailability of dietary fibre complex and phytochemicals, and may increase the uptake of minerals. Microbial metabolism during sourdough fermentation may also produce new nutritionally active compounds, such as peptides and amino acid derivatives (e.g., γ-amino butyric acid) with various functionalities, and potentially prebiotic exo-polysaccharides. The wheat flour digested via fungal proteases and selected sourdough lactobacilli has been demonstrated to be probably safe for celiac patients.

Dietary proteins and functional gastrointestinal disorders

Food intolerance is a common complaint amongst patients with functional gastrointestinal (GI) disorders (FGIDs), including those with irritable bowel syndrome (IBS), functional dyspepsia, as well as gastroesophageal reflux disease. Although there has been a longstanding interest in the possible role of food allergy in IBS, there are limited data supporting the association. However, the prevalence of food allergy is sufficiently high that patients with FGID may also have food allergies or hypersensitivities. Food intolerances or sensitivities are reactions to foods, which are not due to immunological mechanisms. Lactose intolerance is common in the general population and can mimic symptoms of FGID or coexist with FGID. As discussed in other articles in this series, other carbohydrate intolerances may be responsible for symptom generation in patients with IBS and perhaps other FGIDs. There is a great interest in the role of a major dietary protein, gluten, in the production of symptoms that are very similar to those of patients with celiac disease without the enteropathy that characterizes celiac disease. Emerging research into a syndrome known as nonceliac gluten sensitivity suggests a heterogeneous condition with some features of celiac disease but often categorized as FGIDs, including IBS. This article summarizes the role of dietary proteins in the symptoms and pathophysiology of FGIDs.

Human leukocyte antigen DQ2/8 prevalence in non-celiac patients with gastrointestinal diseases

AIM: To investigate the prevalence of human leukocyte antigen (HLA) DQ2/8 alleles in Southern Italians with liver and gastrointestinal (GI) diseases outside of celiac disease.

METHODS: HLA DQ2/8 status was assessed in 443 patients from three ambulatory gastroenterology clinics in Southern Italy (University of Federico II, Naples, Loreto Crispi Hospital, Ruggi D’Aragona Hospital, Salerno). Patients were grouped based on disease status [pre-post transplant liver disease, esophageal/gastric organic and functional diseases, irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD)] and DQ2/8 alleles, which correspond to a celiac disease genetic risk gradient. Subject allele frequencies were compared to healthy Italian controls.

RESULTS: One hundred and ninety-six out of four hundred and forty-three (44.2%) subjects, median age 56 years and 42.6% female, were DQ2/8 positive. When stratifying by disease we found that 86/188 (45.7%) patients with liver disease were HLA DQ2/8 positive, 39/73 (53.4%) with functional upper GI diseases and 19/41 (46.3%) with organic upper GI diseases were positive. Furthermore, 38/105 (36.2%) patients with IBS and 14/36 (38.9%) with IBD were HLA DQ2/8 positive (P = 0.21). Compared to healthy controls those with functional upper GI diseases disorders had a 1.8 times higher odds of DQ2/8 positivity. Those with liver disease had 1.3 times the odds, albeit not statistically significant, of DQ2/8 positivity. Both those with IBS and IBD had a lower odds of DQ2/8 positivity compared to healthy controls.

CONCLUSION: The proportion of individuals HLA DQ2/8 positive is higher in those with liver/upper functional GI disease and lower in IBS/IBD as compared to general population estimates.

Testing for antireticulin antibodies in patients with celiac disease is obsolete: a review of recommendations for serologic screening and the literature

Celiac disease (CD) is an autoimmune disorder that occurs in genetically susceptible individuals of all ages and is triggered by immune response to gluten and related proteins. The disease is characterized by the presence of HLA-DQ2 and/or -DQ8 haplotypes, diverse clinical manifestations, gluten-sensitive enteropathy, and production of several autoantibodies of which endomysial, tissue transglutaminase, and deamidated gliadin peptide antibodies are considered specific. Although antireticulin antibodies (ARA) have historically been used in the evaluation of CD, these assays lack optimal sensitivities and specificities for routine diagnostic use. This minireview highlights the advances in CD-specific serologic testing and the rationale for eliminating ARA from CD evaluation consistent with recommendations for diagnosis.

The dietary intake of wheat and other cereal grains and their role in inflammation

Wheat is one of the most consumed cereal grains worldwide and makes up a substantial part of the human diet. Although government-supported dietary guidelines in Europe and the U.S.A advise individuals to eat adequate amounts of (whole) grain products per day, cereal grains contain “anti-nutrients,” such as wheat gluten and wheat lectin, that in humans can elicit dysfunction and disease. In this review we discuss evidence from in vitro, in vivo and human intervention studies that describe how the consumption of wheat, but also other cereal grains, can contribute to the manifestation of chronic inflammation and autoimmune diseases by increasing intestinal permeability and initiating a pro-inflammatory immune response.

Advances in research of non-coeliac gluten sensitivity

Non-celiac gluten sensitivity (NCGS) is a newly recognized clinical entity that is characterized by a wide variety of intestinal or extra-intestinal manifestations, and it may be the most common one in the spectrum of gluten-related disorders. The symptoms of NCGS improve or disappear after gluten withdrawal and relapse if gluten is reintroduced. There are no specific serological markers for NCGS although nearly half of patients are positive for antigliadin IgG antibodies. Since small intestinal biopsy is normal, the double-blind, placebo-controlled food challenge (DBPCFC) and an exclusion of wheat allergy or coeliac disease are necessary for diagnosis. The pathogenesis is still unclear although immunology may play a role in its pathogenesis. This review will summarize our current knowledge about non-coeliac gluten sensitivity and outline pathogenic and epidemiological differences between NCGS and coeliac disease.

Can an increase in celiac disease be attributed to an increase in the gluten content of wheat as a consequence of wheat breeding?

In response to the suggestion that an increase in the incidence of celiac disease might be attributable to an increase in the gluten content of wheat resulting from wheat breeding, a survey of data from the 20th and 21st centuries for the United States was carried out. The results do not support the likelihood that wheat breeding has increased the protein content (proportional to gluten content) of wheat in the United States. Possible roles for changes in the per capita consumption of wheat flour and the use of vital gluten as a food additive are discussed.

Increased prevalence of antibodies against dietary proteins in children and young adults with cerebral palsy

OBJECTIVES

Undernourishment is common in children with cerebral palsy (CP), but the reasons are unknown. We previously reported elevated levels of immunoglobulin (Ig) A and IgG antibodies against gliadin (AGA) and tissue transglutaminase (tTG) in 99 children and young adults with CP without characteristic findings of gluten enteropathy in small bowel biopsies. Our aim was to perform a case-control study of IgG antibodies against other dietary antigens, AGA, anti-tTG, and IgE antibodies against wheat and gluten.

METHODS

Sera from 99 cases with CP and 99 healthy, age- and sex-matched controls were analysed with fluorescence enzyme-linked immunosorbent assay for detection of IgG antibodies against β-lactoglobulin, casein, egg white, IgG- and IgA-AGA, IgA-anti-tTG, and IgE antibodies against gluten and wheat.

RESULTS

Compared with controls, the odds ratio in cases with CP for having elevated levels of IgG antibodies against β-lactoglobulin was 17.0 (95% confidence interval [CI] 2.3-128), against casein 11.0 (95% CI 2.6-46.8), and against egg white 7.0 (95% CI 1.6-30.8). The IgE responses for wheat/gluten were generally low. The tetraplegic and dyskinetic CP subtypes had significantly higher frequencies of elevated levels for all of the tested antibodies except IgG against egg white, and IgA-anti-tTG. A significantly lower weight was seen in cases with CP with positive versus negative serology.

CONCLUSIONS

Elevated levels of IgG against dietary antigens were more frequent in the CP group compared with controls, and particularly in the tetraplegic and dyskinetic CP subtypes with the most severe neurologic handicap and undernourishment. Hypothetically, malnourishment may cause increased intestinal permeability and thus immunization against dietary antigens.

What role does wheat play in the symptoms of irritable bowel syndrome?

Recently, increasing attention has been paid to the pathologic role of food in irritable bowel syndrome (IBS). Nevertheless, healthcare providers often avoid addressing diet with their patients because of a lack of training, guideline consensus, and high-quality data. Recent literature supports the existence of a subgroup of IBS patients with undiagnosed nonceliac gluten sensitivity (NCGS), a term that is used to describe individuals who experience gastrointestinal and extraintestinal symptoms as a result of immunologic, morphologic, or symptomatic abnormalities that are precipitated by the ingestion of gluten. NCGS represents an important subgroup of patients with IBS who are highly treatable via dietary modification. Gluten may influence gastrointestinal symptoms through immune activation or alteration of intestinal permeability, but the true role of food in functional gastrointestinal symptomatology remains unclear. For example, gluten is just 1 component of the complex milieu of nutrients found in wheat and related grains, and NCGS likely represents only the tip of the iceberg as it pertains to the role of food in IBS.

Frequency of celiac disease in attention-deficit/hyperactivity disorder

OBJECTIVE

Although it is well known that celiac disease (CD) is associated with neurologic disorders, association with psychiatric problems is not well defined. In this report, we aimed to detect CD prevalence in patients with attention-deficit hyperactivity disorder (ADHD).

METHODS

A total of 362 patients between the ages 5 and 15 years with the diagnosis of ADHD according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) diagnostic criteria and 390 sex- and age-matched healthy children were included in the present study. Serum levels of tissue transglutaminase (tTg) immunoglobulin (Ig) A and IgG were studied in both groups. Serum IgA levels were also studied in patients with positive tTG IgG for the exclusion of selective IgA deficiency. Endoscopic duodenal biopsy was provided in seropositive patients, whose parents approved the procedure. Biopsy samples were evaluated according to Marsh-Oberhuber classification.

RESULTS

tTg IgA was positive in 4 patients with ADHD (1.1%). Endoscopic duodenal biopsy was suggestive of CD in one of them (0.27%). tTg IgA was positive in 3 of control group patients (0.8%). Duodenal biopsy of the only patient from control group, who underwent upper gastrointestinal endoscopy, revealed normal intestinal mucosa.

CONCLUSIONS

The seropositivity rates for CD were found similar in ADHD and control groups. Thus, neither routine screening for CD nor empirical recommendation of gluten-free diet seems necessary in children with ADHD.

Celiac and Non-Celiac Forms of Gluten Sensitivity: Shifting Paradigms of an Old Disease

Gluten sensitivity is one of the prominent features of celiac disease (CD) which is an autoimmune disorder characterized by damaged lining of the small intestine. CD was known already to ancient Greeks as κοιλιακός (keeleeakoss) i.e. disease of the abdominal cavity hence celiac. Focus of this Commentary article is on rather complex definition of CD and its emerging new forms the example of which is non-celiac gluten sensitivity. It is becoming evident that to formulate more effective treatments, these associations and newly identified disease entities deserve attention from both academic and clinical communities.

The MS(E)-proteomic analysis of gliadins and glutenins in wheat grain identifies and quantifies proteins associated with celiac disease and baker's asthma

Precise content of gliadin (Glia) and glutenin (Glu) proteins in wheat grain are largely unknown despite their association with celiac disease, various allergies, and physical processing properties of wheat. Developing methods to quantitatively measure clinically relevant proteins could support advancement in understanding exposure thresholds and clinical study design. The aim of this study was to use a data-independent mass spectrometry (MS(E)) approach for quantifying gliadin and glutenin proteins in wheat grain. The biologically replicated analysis yielded concentrations for 34 gliadin and 22 glutenin proteins. The primary focus of this survey was on measuring celiac disease proteins and baker's asthma associated proteins along with the proteins associated with viscoelastic properties of wheat flour and grain texture. The technical coefficients of variation ranged from 0.12 to 1.39 and indicate that MS(E) proteomics is a reproducible quantitative method for the determination of gliadin and glutenin content in the highly complex matrix of protein extracts from wheat grain. This article is part of a Special Issue entitled: Translational Plant Proteomics.

Celiac disease: a challenging disease for pharmaceutical scientists

Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten-containing grains that affects ~1% of the white ethnic population. In the last decades, a rise in prevalence of CD has been observed that cannot be fully explained by improved diagnostics. Genetic predisposition greatly influences the susceptibility of individuals towards CD, though environmental factors also play a role. With no pharmacological treatments available, the only option to keep CD in remission is a strict and permanent exclusion of dietary gluten. Such a gluten-free diet is difficult to maintain because of gluten's omnipresence in food (e.g., additive in processed food). The development of adjuvant therapies which would permit the intake of small amounts of gluten would be desirable to improve the quality of life of patients on a gluten-free diet. Such therapies include gluten-degrading enzymes, polymeric binders, desensitizing vaccines, anti-inflammatory drugs, transglutaminase 2 inhibitors, and HLA-DQ2 blockers. However, many of these approaches pose pharmaceutical challenges with respect to drug formulation and stability, or application route and dosing interval. This perspective article discusses how pharmaceutical scientists may deal with these challenges and contribute to the implementation of novel therapeutic options for patients with CD.

Non-celiac wheat sensitivity diagnosed by double-blind placebo-controlled challenge: exploring a new clinical entity

OBJECTIVES

Non-celiac wheat sensitivity (WS) is considered a new clinical entity. An increasing percentage of the general population avoids gluten ingestion. However, the real existence of this condition is debated and specific markers are lacking. Our aim was thus to demonstrate the existence of WS and define its clinical, serologic, and histological markers.

METHODS

We reviewed the clinical charts of all subjects with an irritable bowel syndrome (IBS)-like presentation who had been diagnosed with WS using a double-blind placebo-controlled (DBPC) challenge in the years 2001-2011. One hundred celiac disease (CD) patients and fifty IBS patients served as controls.

RESULTS

Two hundred and seventy-six patients with WS, as diagnosed by DBPC challenge, were included. Two groups showing distinct clinical characteristics were identified: WS alone (group 1) and WS associated with multiple food hypersensitivity (group 2). As a whole group, the WS patients showed a higher frequency of anemia, weight loss, self-reported wheat intolerance, coexistent atopy, and food allergy in infancy than the IBS controls. There was also a higher frequency of positive serum assays for IgG/IgA anti-gliadin and cytometric basophil activation in "in vitro" assay. The main histology characteristic of WS patients was eosinophil infiltration of the duodenal and colon mucosa. Patients with WS alone were characterized by clinical features very similar to those found in CD patients. Patients with multiple food sensitivity were characterized by clinical features similar to those found in allergic patients.

CONCLUSIONS

Our data confirm the existence of non-celiac WS as a distinct clinical condition. We also suggest the existence of two distinct populations of subjects with WS: one with characteristics more similar to CD and the other with characteristics pointing to food allergy.

Non-celiac wheat sensitivity: separating the wheat from the chat!

Historically, it has been reported that patients with undetected celiac disease (CD) may present with irritable bowel syndrome (IBS) type symptoms. This has led to the recommendation by the American College of Gastroenterology Task force that patients presenting with diarrhea predominant IBS type symptoms should be serologically tested for CD. Concurrently speculative media data suggest that the US general public have increased their uptake of a gluten-free diet (GFD) far in excess of the known prevalence of CD. This may suggest that individuals with gastrointestinal symptoms are deriving benefit from a GFD even if they do not have CD. This has led to the scientific community considering the evidence for an emerging concept of non-celiac wheat sensitivity. There is a significant disparity in our views about what this phenomenon may be. There is also confusion about the nomenclature for this entity and indeed whether patients are suffering due to symptoms related to gluten or perhaps other components of wheat, for example fructans. In this month's edition of the American Journal of Gastroenterology, we see evidence to support the clinical concept of wheat sensitivity or intolerance. Irrespective of the nomenclature Carroccio provides a clinically applicable approach that may be adopted internationally by clinicians. This offers a new option in our armamentarium when seeing patients with IBS type symptoms.

The irritable bowel syndrome-celiac disease connection

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder that has a significant impact on quality of life and health care resources. Celiac disease (CD), a gluten-sensitive enteropathy, can be mistaken for IBS. This article discusses the connection between IBS and CD and the new concept of nonceliac gluten sensitivity (NCGS). NCGS may occur in the presence of a normal or near-normal small bowel biopsy. Some patients with IBS without CD may derive symptomatic benefit from a gluten-free diet. Future research could facilitate a significant impact on the quality of life in this potential subgroup of patients.

Presentation of celiac disease

The mode of presentation of patients with celiac disease has changed dramatically over the recent decades, with diarrheal or classic presentations becoming less common. This trend is most markedly seen in children, whose main presentations include recurrent abdominal pain, growth issues, and screening groups at risk. Among adults, presentations include diarrhea, anemia, osteoporosis, and recognition at endoscopy performed for gastroesophageal reflux disease, as well as screening. The groups most commonly screened include family members of patients with celiac disease, Down syndrome, and autoimmune diseases.

[Gluten-related disorders and demyelinating diseases]

Gluten-related disorders are a spectrum of systemic immune mediated conditions that occur at any age in genetically susceptible individuals upon ingesting gluten. Celiac disease and gluten sensitivity are the most important conditions of the spectrum. They may be associated with other autoimmune diseases, such as multiple sclerosis and neuromyelitis optica. Treatment with a gluten-free diet can provide considerable benefits to the patients having both a gluten-related disorder and one of these 2 demyelinating diseases of the central nervous system.

Gut microbiota, immune development and function

The microbiota of Westerners is significantly reduced in comparison to rural individuals living a similar lifestyle to our Paleolithic forefathers but also to that of other free-living primates such as the chimpanzee. The great majority of ingredients in the industrially produced foods consumed in the West are absorbed in the upper part of small intestine and thus of limited benefit to the microbiota. Lack of proper nutrition for microbiota is a major factor under-pinning dysfunctional microbiota, dysbiosis, chronically elevated inflammation, and the production and leakage of endotoxins through the various tissue barriers. Furthermore, the over-comsumption of insulinogenic foods and proteotoxins, such as advanced glycation and lipoxidation molecules, gluten and zein, and a reduced intake of fruit and vegetables, are key factors behind the commonly observed elevated inflammation and the endemic of obesity and chronic diseases, factors which are also likely to be detrimental to microbiota. As a consequence of this lifestyle and the associated eating habits, most barriers, including the gut, the airways, the skin, the oral cavity, the vagina, the placenta, the blood-brain barrier, etc., are increasingly permeable. Attempts to recondition these barriers through the use of so called 'probiotics', normally applied to the gut, are rarely successful, and sometimes fail, as they are usually applied as adjunctive treatments, e.g. in parallel with heavy pharmaceutical treatment, not rarely consisting in antibiotics and chemotherapy. It is increasingly observed that the majority of pharmaceutical drugs, even those believed to have minimal adverse effects, such as proton pump inhibitors and anti-hypertensives, in fact adversely affect immune development and functions and are most likely also deleterious to microbiota. Equally, it appears that probiotic treatment is not compatible with pharmacological treatments. Eco-biological treatments, with plant-derived substances, or phytochemicals, e.g. curcumin and resveratrol, and pre-, pro- and syn-biotics offers similar effects as use of biologicals, although milder but also free from adverse effects. Such treatments should be tried as alternative therapies; mainly, to begin with, for disease prevention but also in early cases of chronic diseases. Pharmaceutical treatment has, thus far, failed to inhibit the tsunami of endemic diseases spreading around the world, and no new tools are in sight. Dramatic alterations, in direction of a paleolithic-like lifestyle and food habits, seem to be the only alternatives with the potential to control the present escalating crisis. The present review focuses on human studies, especially those of clinical relevance.

Emerging concepts: from coeliac disease to non-coeliac gluten sensitivity

The rise in gluten consumption over time has led to the increasing recognition of coeliac disease (CD) with associated complications. However, only recently has there been an appreciation that the spectrum of gluten-related disorders is greater than just CD, which may explain the growing global popularity in gluten-free products. Current literature suggests that a newly recognised clinical entity in the form of non-coeliac gluten sensitivity (NCGS) may be the most common gluten-related disorder encountered by healthcare professionals, although its exact prevalence is as yet unknown. This article will review the historical relationship between mankind and gluten as well as the progressive recognition that it is possible for gluten to have a deleterious effect on our health. To this effect we discuss the prevalence, diagnosis and complications of CD including the benefits derived from a gluten-free diet (GFD). Finally, we discuss our current understanding of NCGS, in addition to highlighting the need for further research to determine the extent, clinicopathological features and serological biomarkers to help recognise this emerging condition in clinical practice.

Is a gluten-free diet necessary in Marsh I intestinal lesions in patients with HLADQ2, DQ8 genotype and without gastrointestinal symptoms?

PURPOSE OF REVIEW

To describe whether a gluten-free diet (GFD) is indicated in Marsh I gluten-sensitive enteropathy where gastrointestinal symptoms are not present. Arguments are provided to prescribe a GFD to manage extraintestinal symptoms. By contrast, there are not enough reasons to prescribe a GFD to prevent long-term complications.

RECENT FINDINGS

Population-based and prospective observational studies have found that lymphocytic duodenosis may be due to not just gluten-sensitive enteropathy but also due to other aetiologic factors. Marsh I type lesions may be the cause of iron-deficiency anaemia of unknown aetiology which is reverted by a GFD. A similar effect seems to occur with bone mineralization and hypertransaminasemia. The beneficial influence of a GFD reducing lymphoma and coeliac disease-related mortality remains controversial.

SUMMARY

An appropriate differential diagnosis of the lymphocytic duodenosis is essential before a GFD is indicated. As a third of patients remained undiagnosed, in spite of genetic study and specific coeliac serology, flow cytometry and transglutaminase antibodies in duodenal tissue may be helpful in establishing gluten-sensitive enteropathy diagnosis. Future studies should assess whether lymphoma risk is reduced by a GFD in Marsh I patients. Also a more precise benefit in bone mineralization in this setting is needed.

Clinical practice : coeliac disease

Coeliac disease (CD) is an immune-mediated systemic condition elicited by gluten and related prolamines in genetically predisposed individuals and characterised by gluten-induced symptoms and signs, specific antibodies, a specific human leukocyte antigen (HLA) type and enteropathy. The risk of coeliac disease is increased in first-degree relatives, certain syndromes including Down syndrome and autoimmune disorders. It is thought to occur in 1 in 100-200 individuals, but still only one in four cases is diagnosed. Small-bowel biopsy is no longer deemed necessary in a subgroup of patients, i.e. when all of the following are present: typical symptoms or signs, high titres of and transglutaminase antibodies, endomysial antibodies, and HLA-type DQ2 or DQ8. In all other cases, small-bowel biopsy remains mandatory for a correct diagnosis. Therapy consists of a strictly gluten-free diet. This should result in complete disappearance of symptoms and of serological markers. Adequate follow-up is considered essential.

CONCLUSION

Although small-bowel biopsy may be omitted in a minority of patients, small-bowel biopsy is essential for a correct diagnosis of CD in all other cases. Diagnostic work-up should be completed before treatment with gluten-free diet instituted.

Refractory coeliac disease associated with late onset epilepsy, ataxia, tremor and progressive myoclonus with giant cortical evoked potentials--a case report and review of literature

Population-based screening studies suggest an overall prevalence of coeliac disease in Western populations of about 1%. A variety of neurological problems have been associated with coeliac disease occurring in up to 10% of cases of adult coeliac disease. We report an interesting case of a patient with coeliac disease who subsequently developed neurological symptoms several years later. Furthermore, a literature review of all cases to date was performed.

Gluten related disorders

Gluten associated disorders and the question around these associations has recently attracted attentions of many health professionals. This is because of high prevalence of undiagnosed gluten related disorders presenting with a multitude of symptoms and complications inside and outside small bowel. While the environmental factors associated with a complex genetics are leading to destructions of the small intestinal villi resulting in malabsorption syndrome in CD, GS is characterised by negative antibodies and grossly normal histology. The association between celiac disease and other disorders has been clearly established and there have been many reports of numerous intestinal and extra intestinal coexistent disorders with CD. But there is little information available regarding the clinical behavior of gluten sensitivity. In this review we discuss the clinical presentation of non-celiac GS and the prospect of current and the future diagnostic pathway.

The molecular basis for oat intolerance in patients with celiac disease

BACKGROUND

Celiac disease is a small intestinal inflammatory disorder characterized by malabsorption, nutrient deficiency, and a range of clinical manifestations. It is caused by an inappropriate immune response to dietary gluten and is treated with a gluten-free diet. Recent feeding studies have indicated oats to be safe for celiac disease patients, and oats are now often included in the celiac disease diet. This study aimed to investigate whether oat intolerance exists in celiac disease and to characterize the cells and processes underlying this intolerance.

METHODS AND FINDINGS

We selected for study nine adults with celiac disease who had a history of oats exposure. Four of the patients had clinical symptoms on an oats-containing diet, and three of these four patients had intestinal inflammation typical of celiac disease at the time of oats exposure. We established oats-avenin-specific and -reactive intestinal T-cell lines from these three patients, as well as from two other patients who appeared to tolerate oats. The avenin-reactive T-cell lines recognized avenin peptides in the context of HLA-DQ2. These peptides have sequences rich in proline and glutamine residues closely resembling wheat gluten epitopes. Deamidation (glutamine-->glutamic acid conversion) by tissue transglutaminase was involved in the avenin epitope formation.

CONCLUSIONS

We conclude that some celiac disease patients have avenin-reactive mucosal T-cells that can cause mucosal inflammation. Oat intolerance may be a reason for villous atrophy and inflammation in patients with celiac disease who are eating oats but otherwise are adhering to a strict gluten-free diet. Clinical follow-up of celiac disease patients eating oats is advisable.