Celiac sprue

Thermal and Acidic Treatments of Gluten Epitopes Affect Their Recognition by HLA-DQ2 in silico

Celiac disease (CD) is a prevalent disorder with autoimmune features. Dietary exposure of wheat gluten (including gliadins and glutenins) to the small intestine activates the gluten-reactive CD4⁺ T cells and controls the disease development. While the human leukocyte antigen (HLA) is the single most important genetic factor of this polygenic disorder, HLA-DQ2 recognition of gluten is the major biological step among patients with CD. Gluten epitopes are often rich in Pro and share similar primary sequences. Here, we simulated the solution structures changes of a variety of gluten epitopes under different pH and temperatures, to mimic the fermentation and baking/cooking processes. Based on the crystal structure of HLA-DQ2, binding of differently processed gluten epitopes to DQ2 was studied in silico. This study revealed that heating and pH change during the fermentation process impact the solution structure of gluten epitope. However, binding of differently treated gluten epitope peptide (GEP) to HLA-DQ2 mainly depended on its primary amino acid sequence, especially acidic amino acid residues that play a pivotal role in their recognition by HLA-DQ2.

Celiac Disease: Updates on Pathology and Differential Diagnosis

Celiac disease is a gluten-triggered immune-mediated disorder, characterized by inflammation of the enteric mucosa following lymphocytic infiltration and eventually resulting in villous blunting. There have been many developments in refining diagnostic laboratory tests for celiac disease in the last decade. Biopsy-sparing diagnostic guidelines have been proposed and validated in a few recent prospective studies. However, despite these developments, histologic evaluation of duodenal mucosa remains one of the most essential diagnostic tools as it helps in the diagnosis of celiac disease in individuals who do not fulfill the biopsy-sparing diagnostic criteria and in those not responding to a gluten-free diet. Histologic evaluation also allows for the assessment of mucosal recovery after treatment and in the identification of concurrent intestinal diseases. Therefore, pathologists should be familiar with the histologic spectrum of celiac disease and need to be aware of other disorders with similar symptoms and histopathology that may mimic celiac disease. This review aims to provide pathologists with updates on celiac laboratory testing, biopsy-sparing diagnostic criteria, histopathology, complications, and differential diagnoses of celiac disease.

Pathogenesis of Enteropathy-Associated T Cell Lymphoma

PURPOSE OF REVIEW

To provide an update on the pathogenesis of enteropathy-associated T cell lymphoma (EATL) and its relationship with refractory celiac disease (RCD), in light of current knowledge of immune, genetic, and environmental factors that promote neoplastic transformation of intraepithelial lymphocytes (IELs).

RECENT FINDINGS

EATL frequently evolves from RCD type II (RCD II) but can occur "de novo" in individuals with celiac disease. Recurrent activating mutations in members of the JAK/STAT pathway have been recently described in EATL and RCD II, which suggests deregulation of cytokine signaling to be an early event in lymphomagenesis. Intraepithelial T cells are presumed to be the cell of origin of EATL (and RCD II). Recent in vitro molecular and phenotypic analyses and in vivo murine studies, however, suggest an origin of RCD II from innate IELs (NK/T cell precursors), which could also be the cell of origin of RCD II-derived EATL. The immune microenvironment of the small intestinal mucosa in celiac disease fosters the development of EATL, often in a multistep pathway.

Thyroid and celiac disease in pediatric age: a literature review

Chronic autoimmune thyroid disease or Hashimoto thyroiditis (HT) and Graves-Basedow disease (GD) are the main autoimmune thyroid diseases in pediatric age. Both are characterized by the production of anti-thyroid antibodies, by an infiltration of autoreactive B and T lymphocytes into the thyroid parenchyma and by alterations in thyroid function (hyperthyroidism in GD, normal function or subclinical hypothyroidism in HT with possible evolution towards manifest hypothyroidism). Celiac disease (CD) is a systemic autoimmune disease caused by gluten ingestion in genetically predisposed subjects, its prevalence is around 1% in Western Countries. It presents with a pathognomonic enteropathy, a variety of clinical manifestations, positivity for specific antibodies, positivity for typical haplotypes HLA DQ2/DQ8. The clinical manifestations may vary among four types: typical, atypical, silent and latent. Diagnosis can be made in presence of specific histopathologic findings in duodenal biopsies and antibodies positivity. Celiac disease is associated to various endocrine autoimmunities such as thyropathies, diabetes mellitus type 1, Addison disease, multiendocrine syndromes. The most frequent associated thyropaties are HT and GD. The present review aims to explore the associations between thyropathies and celiac disease in pediatric age.

Unraveling the structural basis for the unusually rich association of human leukocyte antigen DQ2.5 with class-II-associated invariant chain peptides

Human leukocyte antigen (HLA)-DQ2.5 (DQA1*05/DQB1*02) is a class-II major histocompatibility complex protein associated with both type 1 diabetes and celiac disease. One unusual feature of DQ2.5 is its high class-II-associated invariant chain peptide (CLIP) content. Moreover, HLA-DQ2.5 preferentially binds the non-canonical CLIP2 over the canonical CLIP1. To better understand the structural basis of HLA-DQ2.5's unusual CLIP association characteristics, better insight into the HLA-DQ2.5·CLIP complex structures is required. To this end, we determined the X-ray crystal structure of the HLA-DQ2.5· CLIP1 and HLA-DQ2.5·CLIP2 complexes at 2.73 and 2.20 Å, respectively. We found that HLA-DQ2.5 has an unusually large P4 pocket and a positively charged peptide-binding groove that together promote preferential binding of CLIP2 over CLIP1. An α9-α22-α24-α31-β86-β90 hydrogen bond network located at the bottom of the peptide-binding groove, spanning from the P1 to P4 pockets, renders the residues in this region relatively immobile. This hydrogen bond network, along with a deletion mutation at α53, may lead to HLA-DM insensitivity in HLA-DQ2.5. A molecular dynamics simulation experiment reported here and recent biochemical studies by others support this hypothesis. The diminished HLA-DM sensitivity is the likely reason for the CLIP-rich phenotype of HLA-DQ2.5.

Megaloblastic Anemias: Nutritional and Other Causes

Vitamin B₁₂ and folate deficiencies are major causes of megaloblastic anemia. Causes of B₁₂ deficiency include pernicious anemia, gastric surgery, intestinal disorders, dietary deficiency, and inherited disorders of B₁₂ transport or absorption. The prevalence of folate deficiency has decreased because of folate fortification, but deficiency still occurs from malabsorption and increased demand. Other causes include drugs and inborn metabolic errors. Clinical features of megaloblastic anemia include anemia, cytopenias, jaundice, and megaloblastic marrow morphology. Neurologic symptoms occur in B₁₂ deficiency, but not in folate deficiency. Management includes identifying any deficiency, establishing its cause, and replenishing B₁₂ or folate parenterally or orally.

Comparison of clinical features, treatment, and outcomes of collagenous sprue, celiac disease, and collagenous colitis

BACKGROUND

Collagenous sprue (CS) is a rare form of enteropathy that had been reported to be associated with celiac disease (CD) and collagenous colitis (CC). The aim of our study was to compare the clinical features, treatments, and outcomes of CS, CD, and CC.

METHODS

All patients with histologic diagnosis of CS, CD, or CC with complete clinical data were extracted from our pathology database between 1990 and 2015. Demographic and clinical features were recorded along with treatments and outcomes.

RESULTS

A total of 21 patients with CS were included. Overall CS patients were more symptomatic with 17 (81.0%) patients with diarrhea and 15 (71.4%) with unintentional weight loss. Positive celiac serology was noted in 5 (23.8%) CS patients. CS patients had higher rates for disease-related temporary total parenteral nutrition (TPN) use (38.1% vs. 1.1% vs. 1.0%, P < 0.0001) and disease-related hospitalization (52.4% vs. 3.3% vs. 8.2%, P < 0.0001) than that in CD and CC patients. Twenty CS patients received treatments, including the combination of gluten-free diet (GFD) and corticosteroids (n = 12), GFD only (n = 2), and corticosteroids only (n = 6). All CS patients showed symptomatic reliefs with treatment. Although CS patients had a higher rate for hospitalization and TPN use, disease-related death was not observed in all three groups.

CONCLUSIONS

Collagenous sprue patients had more severe clinical presentation than patients with CD and CC and therefore had higher demand for temporary TPN and hospitalization. Nevertheless, a prompt use of steroids and/or GFD upon histologic diagnosis of CS may have contributed to an overall excellent prognosis.

Trichotillomania in Celiac Disease

Trichotillomania is an underreported and underdiagnosed condition associated with significant impairments in social and functional relationships. The connection between celiac disease and trichotillomania is not yet established clearly. Only a few cases of trichotillomania have been reported to date. Here, we report the case of a 22-year-old Saudi female, who presented with celiac disease and trichotillomania to the psychiatry clinic. This is the first report of its kind in Saudi Arabia. By reporting this case, I highlight the importance of psychiatric and comprehensive approaches in patients with celiac disease.

Minimally symptomatic hypocalcaemia unmasking celiac disease

INTRODUCTION

Celiac disease is an autoimmune disease of the small intestine which occurs in genetically predisposed people of all ages. A large clinical spectrum of manifestations accompanies the onset of the disease with diarrhoea, flatulence and weight loss being the most common. However, findings like osteoporosis, iron deficiency, anaemia and hypocalcaemia could also insinuate the existence of the disease.

CASE PRESENTATION

We report the case of a 55-year-old man with numbness and tingling of the upper extremities due to hypocalcaemia that proved to be an uncommon case of celiac disease.

CONCLUSION

A non-negligible number of adult patients with celiac disease can present with only minor and subclinical manifestations of the disease. As such, hypocalcaemia may be the sole manifestation of celiac disease. A high index of suspicion is needed for prompt diagnosis.

The Role of T-Cell Subsets in Chronic Inflammation in Celiac Disease and Inflammatory Bowel Disease Patients: More Common Mechanisms or More Differences?

Background

Chronic intestinal inflammation due to noninfectious causes represents a growing health issue all over the world. Celiac disease as well as inflammatory bowel diseases (IBD) like Crohn's disease and ulcerative and microscopic colitis involve uncontrolled T-cell activation and T-cell-mediated damage as common denominators. Therefore, diagnosis and treatment decisions clearly benefit from the knowledge of the intricacies of the systemic and the local T-cell activity.

Summary

Depending on the cytokine milieu, CD4⁺ T cells can differentiate into proinflammatory T helper 1 (Th1), anti-inflammatory Th2, antimicrobial Th17, pleiotropic Th9, tissue-instructing Th22 cells, and in the regulatory compartment forkhead box protein 3⁺ Treg, suppressive Tr1 or Th3 cells. Additionally, follicular Th cells provide B-cell help in antibody class switching; cytotoxic CD8⁺ T cells target virus-infected or tumor cells. This review discusses our current knowledge on the contribution of defined T-cell subpopulations to establishing and maintaining chronic intestinal inflammation in either of the above entities. It also puts emphasis on the differences in the prevalence of these diseases between Eastern and Western countries.

Key Messages

In celiac disease, the driving role of T cells in the lamina propria and in the epithelium mainly specific for two defined antigens is well established. Differences in genetics and lifestyle between Western and Eastern countries were instrumental in understanding underlying mechanisms. In IBD, the vast amount of potential antigens and the corresponding antigen-specific T cells makes it unlikely to find universal triggers. Increased mucosal CD4⁺ regulatory T cells in all four entities fail to control or abrogate local inflammatory processes. Thus, prevailing differences in the functional T-cell subtypes driving chronic intestinal inflammation in celiac disease and IBD at best allow some overlap in the treatment options for either disease.

A comparison of the nutritional status between adult celiac patients on a long-term, strictly gluten-free diet and healthy subjects

BACKGROUND/OBJECTIVES

There are conflicting data on the effect of a gluten-free diet (GFD) on the nutritional status of celiac patients. In the present study, we evaluated, in adult celiac patients, the influence of a long-term, strictly GFD on their nutritional status and compared it with matched healthy volunteers.

SUBJECTS/METHODS

Our study included 39 celiac patients and 39 healthy volunteers. The body mass index (BMI) of patients and controls was evaluated at enrollment, while the patients' BMI before the GFD was retrieved from clinical records. In addition, at enrollment, in both groups, we compared BMI, fat mass (FM), bone mineral density (BMD), as well as their dietary intake, recorded on a 7-day diary.

RESULTS

At the time of diagnosis, the majority of celiac patients (82.0%) had a normal BMI or were overweight, while 10.3% were malnourished. After the GFD, patients with a normal BMI showed a significant weight increase (P=0.002), but none of them switched in the overweight or obese category. Two (50%) of the four malnourished patients achieved a normal BMI. Controls and patients on a GFD had a similar BMI, FM, BMD and total calorie intake, but the amount of lipids and fiber intake was significantly different in the two groups (P=0.003 and P<0.0001, respectively).

CONCLUSIONS

Our study demonstrates that a GFD is able to improve the nutritional status of celiac patients without inducing overweight or obesity. Our findings are related to a celiac population adopting a GFD based on a Mediterranean-type diet.

Serological markers of enterocyte damage and apoptosis in patients with celiac disease, autoimmune diabetes mellitus and diabetes mellitus type 2

Impairment of mucosal barrier integrity of small intestine might be causative in immune-mediated gastrointestinal diseases. We tested the markers of epithelial apoptosis - cytokeratin 18 caspase-cleaved fragment (cCK-18), and enterocyte damage - intestinal fatty acid-binding protein (I-FABP) and soluble CD14 (sCD14) in sera of patients with untreated celiac disease (CLD), those on gluten-free diet (CLD-GFD), patients with autoimmune diabetes mellitus (T1D), T1D with insulitis (T1D/INS), and diabetes mellitus type 2 (T2D). We found elevated levels of cCK-18 (P<0.001), I-FABP (P<0.01) and sCD14 (P<0.05) in CLD when compared to healthy controls. However, the levels of cCK-18 (P<0.01) and I-FABP (P<0.01) in CLD-GFD were higher when compared with controls. Interestingly, elevated levels of cCK-18 and I-FABP were found in T2D and T1D (P<0.001), and T1D/INS (P<0.01, P<0.001). Twenty-two out of 43 CLD patients were seropositive for cCK-18, 19/43 for I-FABP and 11/43 for sCD14; 9/30 of T2D patients were positive for cCK-18 and 5/20 of T1D/INS for sCD14, while in controls only 3/41 were positive for cCK-18, 3/41 for I-FABP and 1/41 for sCD14. We documented for the first time seropositivity for sCD14 in CLD and potential usefulness of serum cCK-18 and I-FABP as markers of gut damage in CLD, CLD-GFD, and diabetes.

Changes in natural Foxp3(+)Treg but not mucosally-imprinted CD62L(neg)CD38(+)Foxp3(+)Treg in the circulation of celiac disease patients

Background

Celiac disease (CD) is an intestinal inflammation driven by gluten-reactive CD4⁺ T cells. Due to lack of selective markers it has not been determined whether defects in inducible regulatory T cell (Treg) differentiation are associated with CD. This is of importance as changes in numbers of induced Treg could be indicative of defects in mucosal tolerance development in CD. Recently, we have shown that, after encounter of retinoic acid during differentiation, circulating gut-imprinted T cells express CD62L^negCD38⁺. Using this new phenotype, we now determined whether alterations occur in the frequency of natural CD62L⁺Foxp3⁺ Treg or mucosally-imprinted CD62L^negCD38⁺Foxp3⁺ Treg in peripheral blood of CD patients. In particular, we compared pediatric CD, aiming to select for disease at onset, with adult CD.

Methods

Cell surface markers, intracellular Foxp3 and Helios were determined by flow cytometry. Foxp3 expression was also detected by immunohistochemistry in duodenal tissue of CD patients.

Results

In children, the percentages of peripheral blood CD4⁺Foxp3⁺ Treg were comparable between CD patients and healthy age-matched controls. Differentiation between natural and mucosally-imprinted Treg on the basis of CD62L and CD38 did not uncover differences in Foxp3. In adult patients on gluten-free diet and in refractory CD increased percentages of circulating natural CD62L⁺Foxp3⁺ Treg, but normal mucosally-imprinted CD62L^negCD38⁺Foxp3⁺ Treg frequencies were observed.

Conclusions

Our data exclude that significant numeric deficiency of mucosally-imprinted or natural Foxp3⁺ Treg explains exuberant effector responses in CD. Changes in natural Foxp3⁺ Treg occur in a subset of adult patients on a gluten-free diet and in refractory CD patients.

Seroprevalence of celiac disease among healthy adolescents in Saudi Arabia

AIM: To identify the seroprevalence of celiac disease among healthy Saudi adolescents.

METHODS: Between December 2007 and January 2008, healthy students from the 10^th to 12^th grades were randomly selected from three regions in Saudi Arabia. These regions included the following: (1) Aseer region, with a student population of 25512; (2) Madinah, with a student population of 23852; and (3) Al-Qaseem, with a student population of 16067. Demographic data were recorded, and a venous blood sample (5-10 mL) was taken from each student. The blood samples were tested for immunoglobulin A and immunoglobulin G endomysial antibodies (EMA) by indirect immunofluorescence.

RESULTS: In total, 1167 students (614 males and 553 females) from these three regions were randomly selected. The majority of the study population was classified as lower middle class (82.7%). There were 26 (2.2%) students who had a positive anti-EMA test, including 17 females (3.1%) and 9 males (1.5%). Al-Qaseem region had the highest celiac disease prevalence among the three studied regions in Saudi Arabia (3.1%). The prevalence by region was as follows: Aseer 2.1% (10/479), Madinah 1.8% (8/436), and Al-Qaseem 3.2% (8/252). The prevalence in Madinah was significantly lower than the prevalence in Aseer and Al-Qaseem (P = 0.02).

CONCLUSION: Our data suggest celiac disease prevalence might be one of the highest in the world. Further studies are needed to determine the real prevalence.

Intakes of nutrients in Italian children with celiac disease and the role of commercially available gluten-free products

BACKGROUND

Celiac disease (CD) is a chronic gluten-sensitive enteropathy. Life-long gluten-free diet (GFD) is the only therapeutic option; however, it may contribute to the consumption of an unbalanced diet. The present study aimed to evaluate the dietary intake of CD affected children on a GFD and compare it with non-celiac children and with Italian nutritional intakes recommendations, as well as evaluate the contribution of commercially available gluten-free products (GFPs).

METHODS

Eighteen celiac children, median age 7.6 years, median GFD duration 4.2 years, and 18 non-celiac controls, were enrolled in a cross-sectional age-matched study. Dietary intakes of both groups were collected using a food frequency questionnaire and a 24-hour dietary recall. Nutritional intakes were compared between the group and controls and with Italian dietary reference values. The contribution of GFPs to energy and macronutrient intakes was evaluated.

RESULTS

Median energy intake was significantly higher in CD patients than in controls (8961.8 and 5761.0 kJ day(-1); P < 0.001). CD subjects showed higher carbohydrate intakes and lower fat intakes compared to controls. Protein-derived energy did not differ. By contrast to control subjects, energy derived from carbohydrate intakes in CD children met the Italian recommendations. Both children groups showed higher protein and fat intakes than recommended in Italy. GFPs consumption accounted for 36.3% of daily total energy intake.

CONCLUSIONS

Intakes of simple sugars, fats and protein exceeded the National recommendations for health. Children with CD had significantly higher energy intakes than controls, although body mass index was comparable across the groups. Lack of nutritional information for GFPs prevented complete dietary analysis of subfractions of fat and micronutrient intakes. This aspect need to be addressed if studies in this field are to be meaningful in the future.

Enzyme linked immuno-spot; a useful tool in the search for elusive immune markers in common pediatric immunological diseases

In order to provide better therapy we strive to increase our knowledge of how the immune system behaves and communicates in common pediatric immunological diseases, such as type 1 diabetes, allergic and celiac diseases. However, when dealing with pediatric diseases, where study subjects are almost exclusively children, blood volumes available for immunological studies are limited and as such must be carefully handled and used to their full extent. Single immune markers can easily be detected by a traditional Enzyme Linked Immunosorbent Assay (ELISA), whereas multiple markers can be detected by a fluorochrome (Luminex) or electrochemiluminescence (MSD) technique. These techniques however are sometimes not sensitive enough to detect low levels of secreted immune markers in limited sample sizes. To detect immune markers at the single-cell level, an Enzyme Linked Immuno-spot (ELISPOT) can be used to pin-point elusive immune markers in common pediatric immunological diseases.

Coeliac Disease in the 21st Century: No Longer "Kids' Stuff"

Background

We aimed to determine if Coeliac disease (CD) can be still be considered a predominantly paediatric disorder, in spite of the increased incidence of adult-onset CD reported in recent years.

Methods

An observational, descriptive, and retrospective study was developed at two Spanish hospitals. Data was collected and analyzed from all paediatric and adult patients newly diagnosed with CD throughout the year 2010. CD diagnoses were based on a concordant clinical history, serology, HLA-DQ compatibility, the presence of mucosal lesions in duodenal biopsies with gluten dependence of symptoms, and histological lesions.

Results

A total of 79 patients were diagnosed with CD throughout 2010, of which 68 (86.1%) were adults. Classic symptoms (diarrhoea and iron-deficiency anaemia) were more frequent in children (90.9%), being present in only 54.4% of adults (p = 0.02). Adult patients showed, mainly, abdominal pain, dyspepsia, and GERD-related symptoms. Villous atrophy (Marsh III) was present in 63.7% of children, but only in 19.1% of adults (p = 0.004). Positive tTGA was present in 81.8% of the children and only in 19.1% of the adults (p = 0.004). Haemoglobin levels were significantly lower in children (p = 0.025), but no differences were observed in iron and ferritin blood levels.

Conclusions

Our study shows that adult-onset CD was the predominant presentation in two hospitals in Spain in the year 2010. Therefore, CD can no longer be considered a predominantly paediatric disorder. Marsh I and negative tTGA titters are characteristic in most of adults. New diagnostic algorithms are needed to improve correct diagnosis of CD in adults.

Genetic and dental study of patients with celiac disease

OBJECTIVES

The aim of this work was to study the pattern of inheritance of celiac disease in a group of Saudi patients and to compare oral mucosal and dental clinical findings in these patients to those of healthy controls.

STUDY DESIGN

Fifty patients suffering from celiac disease were screened for dental evaluation. They were subjected to clinical genetic examination, pedigree construction, oral mucosal and dental clinical evaluation.

RESULTS

An autosomal recessive mode of inheritance was evident in some of the studied cases, while others showed sporadic occurrence. Oral mucosal and dental clinical examinations revealed recurrent oral ulcerations, enamel hypoplasia in most of the celiac disease patients.

CONCLUSIONS

Pedigree analysis of families is important to identify the mode of inheritance. Oral mucosal and dental clinical examinations are important in diagnosing and monitoring cases of celiac disease.

The incidence and clinical spectrum of refractory celiac disease in a north american referral center

OBJECTIVES

Refractory celiac disease (RCD) is one of the most serious causes of persistent symptoms in patients with celiac disease (CD). Published reports suggest that approximately half of patients in Europe are RCD type II, which carries a poor prognosis with a 5-year survival rate of ~50% compared with ~90% for RCD type I. However, disease patterns may be different in North America. The aim of this study was to explore the clinical spectrum of RCD in a North American population.

METHODS

Medical records of patients with biopsy-proven CD presenting to our institution were reviewed for a diagnosis of RCD. Demographic data, clinical characteristics, and mortality were evaluated and compared with our general CD population.

RESULTS

In all, 34 out of 844 (4.0%) CD patients had RCD. The cumulative incidence of RCD for patients diagnosed with CD at our center was 1.5%. Unintentional weight loss at diagnosis of RCD was found in 76.5% (n=26) compared with 16.7% (n=141) at diagnosis of CD (P<0.0001) and diarrhea at diagnosis of RCD was found in 79.4% (n=27) compared with 40.5% (342) at diagnosis of CD (P<0.0001). Five patients (14.7%) were diagnosed with RCD type II and of these, two died of enteropathy-associated lymphoma within 24 months of diagnosis of CD (observed mortality rate 5.9%).

CONCLUSIONS

Although RCD is a serious condition with significant morbidity; the observed mortality rates are low in our population. This study suggests that RCD may be less severe in North American vs. European populations.

Adult patients with eosinophilic esophagitis do not show an increased frequency of the HLA-DQ2/DQ8 genotypes predisposing to celiac disease

BACKGROUND

Recent articles have described patients that share eosinophilic esophagitis (EoE) and celiac disease (CD) suggesting a true relationship between both diseases.

AIMS

The purpose of this study was to investigate whether HLA DQ2 and DQ8 predisposing to CD are increased in adult patients with EoE.

METHODS

HLA alleles conferring risk for CD was assessed in 75 adult EoE patients attended at two hospitals located in different Spanish regions over the past 2 years. We compared the frequencies to the registered data of 421 healthy kidney and bone marrow donors from our hospitals for the following alleles: (a) DR3-DQ2 haplotype; (b) the combination of DR3-DQ2 and DR4-DQ8; (c) DR4-DQ8 haplotype; (d) the simultaneous presence of the DR5-DQ7 and DR7-DQ2 haplotypes; and lastly (e) any combination of haplotypes not conferring risk for the development of CD.

RESULTS

The HLA DQ2 and DQ8 alleles were analyzed in 58 adult EoE patients from hospital #1 and in 20 patients from hospital #2, and they were compared to recorded HLA genotyping data from 298 and 123 healthy donors, respectively. No differences were found between the distribution of the HLA frequencies of the patients and controls at both hospitals and the data could be combined. EoE patients did not show increased frequencies of DQ2 and DQ8 alleles compared to controls.

CONCLUSIONS

Our work does not allow us to establish a common genetic basis for EoE and CD because an increased frequency of the HLA DQ2 and DQ8 alleles predisposing to CD was not observed in adult EoE patients compared to controls.

Hepatobiliary disorders in celiac disease: an update

This communication reviews recent literature and summarizes hepatobiliary abnormalities that may complicate the clinical course of celiac disease. A wide spectrum of hepatobiliary diseases has been described, including asymptomatic elevations of liver enzyme levels, nonspecific hepatitis, nonalcoholic fatty liver disease, and autoimmune and cholestatic liver disease. Moreover, in the majority of patients, liver enzyme levels will normalize on a gluten-free diet. In addition, celiac disease may be associated with rare hepatic complications, such as hepatic T-cell lymphoma. Because many celiac patients do not have overt gastrointestinal symptoms, a high index of suspicion is required. Simple methods of detecting celiac disease such as serum antibody tests help in the early identification of the disease, thus preventing serious complications of the disorder. The IgG DGP antibody test and IgA tTG antibody test used in combination are an excellent screening test for suspected cases of celiac disease.

Are patients with potential celiac disease really potential? The answer of metabonomics

Celiac disease (CD) is an autoimmune disorder caused by a permanent sensitivity to gluten in genetically susceptible individuals. Accurate diagnosis of CD at an early stage and its treatment with a gluten-free diet (GFD) are important for optimum treatment and prognosis. Recently, by employing a noninvasive metabonomic approach, we have shown that CD has a well-defined metabonomic signature. Here we address potential CD patients, defined as subjects who do not have, and have never had, a jejunal biopsy consistent with clear CD, and yet have immunological abnormalities similar to those found in celiac patients. Sixty-one overt CD patients at diagnosis, 29 patients with potential CD, and 51 control subjects were examined by (1)H NMR of their serum and urine: out of 29 potential CD patients, 24 were classified as CD and 5 as control subjects. Potential CD largely shares the metabonomic signature of overt CD. Most metabolites found to be significantly different between control and CD subjects were also altered in potential CD. Our results demonstrate that metabolic alterations may precede the development of small intestinal villous atrophy and provide a further rationale for early institution of GFD in patients with potential CD, as recently suggested by prospective clinical studies.

Celiac disease: from pathogenesis to novel therapies

Celiac disease has become one of the best-understood HLA-linked disorders. Although it shares many immunologic features with inflammatory bowel disease, celiac disease is uniquely characterized by (1) a defined trigger (gluten proteins from wheat and related cereals), (2) the necessary presence of HLA-DQ2 or HLA-DQ8, and (3) the generation of circulating autoantibodies to the enzyme tissue transglutaminase (TG2). TG2 deamidates certain gluten peptides, increasing their affinity to HLA-DQ2 or HLA-DQ8. This generates a more vigorous CD4(+) T-helper 1 T-cell activation, which can result in intestinal mucosal inflammation, malabsorption, and numerous secondary symptoms and autoimmune diseases. Moreover, gluten elicits innate immune responses that act in concert with the adaptive immunity. Exclusion of gluten from the diet reverses many disease manifestations but is usually not or less efficient in patients with refractory celiac disease or associated autoimmune diseases. Based on the advanced understanding of the pathogenesis of celiac disease, targeted nondietary therapies have been devised, and some of these are already in phase 1 or 2 clinical trials. Examples are modified flours that have been depleted of immunogenic gluten epitopes, degradation of immunodominant gliadin peptides that resist intestinal proteases by exogenous endopeptidases, decrease of intestinal permeability by blockage of the epithelial ZOT receptor, inhibition of intestinal TG2 activity by transglutaminase inhibitors, inhibition of gluten peptide presentation by HLA-DQ2 antagonists, modulation or inhibition of proinflammatory cytokines, and induction of oral tolerance to gluten. These and other experimental therapies will be discussed critically.

A blinded pilot comparison of capsule endoscopy and small bowel histology in unresponsive celiac disease

This study compares video capsule endoscopy (VCE) with histological specimens of proximal small bowel in patients with celiac disease who have failed to respond to a gluten-free diet. Patients with nonresponsive celiac disease underwent capsule endoscopy, and concordance between endoscopy and histology was then calculated using the kappa statistic. In 19 patients, endoscopy videos were reported as normal in ten (53%) case, as having mild changes in three (16%) cases, and as having moderate-severe changes in six (31%) cases. Two (11%) had acute ulcers. No small bowel tumors were seen. Endoscopy demonstrated concordance with histological changes in 14 of the 18 patients with histology available (78% concordance). The kappa statistic suggested a substantial degree of concordance between histology and endoscopic findings. Endoscopy with distal duodenal biopsies is superior to VCE in detecting proximal, nonresponsive celiac disease, but more distal lesions may be missed such that the strength of VCE lies in its ability to visualize the entire small bowel.

The significance of coeliac disease antibodies in patients with ankylosing spondylitis: a case-controlled study

The presence of anti-gliadin antibodies (AGA) and their relationship with intestinal permeability and prevalence of undiagnosed coeliac disease (CD) in ankylosing spondylitis (AS) were investigated. Blood samples from 30 AS patients and 19 age- and sex-matched controls were analysed for human leucocyte antigen (HLA)-B27, AGA and endomysial antibodies (EMA). Immunoglobulin (Ig) A-type AGA and IgG-type EMA were determined by enzyme-linked immunosorbent assay. AGA-positive patients were examined by gastroduodenoscope and proximal small bowel mucosa biopsies were performed. Eleven (36.7%) AS patients were AGA positive (compared with none of the control subjects) and three (10.0%) of these AS patients were also EMA-positive. The presence of AGA was not associated with more severe AS. Mild-to-severe villous atrophy and hyperplasia of crypts with increased chronic inflammatory cells in the lamina propria, which is typical of CD, was only observed in one AGA/EMA positive AS patient; CD was subsequently diagnosed by histology. Although AGA positivity might contribute to the pathogenesis of AS by increasing intestinal permeability to micro-organisms or by modifying intestinal immune mechanisms, further work is required to clarify its role in AS.

Clinical staging and survival in refractory celiac disease: a single center experience

BACKGROUND & AIMS

Refractory celiac disease (RCD) occurs when both symptoms and intestinal damage persist or recur despite strict adherence to a gluten-free diet. In RCD, the immunophenotype of intraepithelial lymphocytes may be normal and polyclonal (RCD I) or abnormal and monoclonal (RCD II). The aim is to describe the clinical characteristics, treatment, and long-term outcome in a large single-center cohort of patients with RCD.

METHODS

We compared the clinical characteristics and outcome in 57 patients with RCD: 42 with RCD I and 15 with RCD II.

RESULTS

Fifteen of 57 patients died during follow-up (n=8 with RCD I and n=7 with RCD II), each within the first 2 years after RCD diagnosis. The overall 5-year cumulative survival is 70%, 80%, and 45% for the entire cohort, RCD I, and RCD II, respectively. The refractory state itself and enteropathy-associated T-cell lymphoma (EATL) were the most common causes of death, respectively. A new staging system is proposed based on the cumulative effect of 5 prognostic factors investigated at the time of the refractory state diagnosis: for patients in stages I, II, and III, the 5-year cumulative survival rate was 96%, 71%, and 19%, respectively (P< .0001).

CONCLUSIONS

RCD is associated with high mortality with RCD II having an especially poor prognosis because of the development of EATL. A new staging model is proposed that may improve the precision of prognosis in patients with RCD.

Unkilned and large amounts of oats in the coeliac disease diet: a randomized, controlled study

OBJECTIVE

There is evidence for the long-term safety of oats as part of a gluten-free diet in coeliac disease (CD). Oats is generally processed by kilning, which theoretically may change its antigenic properties and be the reason that it is tolerated by patients with CD. The aim of this study was to investigate the suitability of large amounts of unkilned oats, comparing its use with kilned oats in adult coeliac patients.

MATERIAL AND METHODS

The study group included 13 men and 19 women with CD in remission. The goal of daily intake of oats was 100 g during one year. These patients using oats as part of their gluten-free diet were randomized to two treatment groups. One group used regular oats and the other unkilned oats. After 6 months the patients changed the treatment groups. Food intake, symptoms, histology of the small intestine and the levels of endomysial antibodies were noted.

RESULTS

No marked changes were found in the duodenal biopsies, in the levels of endomysial antibodies or in the well-being of the patients. Compliance with the diet did not change during the follow-up.

CONCLUSIONS

Large amounts of both unkilned and regular kilned oats are well tolerated by adult patients with CD. Oats is therefore not harmful, even in its unkilned form, which indicates that its antigenic nature is not changed by common industrial food processing in such a way that would prevent the provoking of CD.

Co-occurrence of celiac disease and other autoimmune diseases in celiacs and their first-degree relatives

The occurrence of other autoimmune diseases in celiac disease families has not been previously reported in a North American population. We investigated the familial aggregation of rheumatoid arthritis (RA), juvenile rheumatoid arthritis/juvenile idiopathic arthritis (JRA/JIA), hypothyroidism, insulin dependent diabetes mellitus (IDDM), and alopecia areata (AA) among individuals in families with celiac disease (CD). Family history information, obtained from questionnaires from the University of California Irvine Celiac Disease study, was reviewed for reports of RA, JRA/JIA, hypothyroidism, IDDM, and AA in celiac disease cases and their first-degree relatives. Reports of disease were compared with prevalence data from the literature and analyzed by calculating the standardized ratio (SR) with 95% confidence limits. We analyzed: (1) subjects with confirmed celiac disease or dermatitis herpetiformis (205 probands and 203 affected first-degree relatives) and (2) first-degree relatives of celiac disease cases (n=1272). We found a significantly increased number of cases, relative to the expected number, of IDDM in both groups and hypothyroidism among subjects with celiac disease. JRA/JIA was increased among first-degree relatives of celiacs. These results indicate that the presence of IDDM within our celiac disease families may be due to shared genetic susceptibility predisposing to these diseases or autoimmune diseases in general.

Antroduodenojejunal motor activity in untreated and treated celiac disease patients

BACKGROUND AND AIM

Patients with celiac disease may present with abnormal upper gut motor activity. However, it is not known if these abnormalities persist after the introduction of a gluten-free diet. The present study aimed to compare antroduodenojejunal motor variables recorded in untreated celiac patients with those of celiac patients given a gluten-free diet and healthy volunteers.

METHODS

Eleven untreated celiac disease patients, 12 age- and sex-matched celiac patients on a gluten-free diet (at least 12 months), and 33 controls entered the study. Antroduodenojejunal motility was recorded for 6 h during fasting and for 3 h after a standard meal by means of a perfused, multiple lumen catheter.

RESULTS

More than 80% of untreated celiac patients had discrete motor abnormalities of the upper gut, in both fasting and fed recordings, compared to the other subjects. Patients on a gluten-free diet also showed motor abnormalities, albeit to a lesser extent. In these patients histological evaluation showed the persistence of mild mucosal abnormalities.

CONCLUSIONS

Upper gut motor abnormalities are frequent in patients with celiac disease, even in those on a gluten-free diet. In the latter group, these abnormalities may suggest an incomplete adherence to the dietary regimen.

Extracts of wheat gluten activate complement via the alternative pathway

We studied the ability of wheat gluten and its subfractions to activate complement directly. A sensitive sandwich ELISA employing a monoclonal antibody (MoAb) to a C9 neoepitope exposed in the terminal complement complex (TCC), a functional haemolytic assay for C5b6 generation, and LaurelFs electrophoretic method of estimating C3 conversion to C3bi were used. On a weight-for-weight basis, enzyme solubilized Frazer's fraction three of gluten (Fill) produced approximately 75% of the complement activation seen with the potent activator zymosan. By contrast, activation with whole insoluble undigested gluten was very weak and similar to that seen with ovalbumin or β-lactoglobulin. The results were the same using normal human serum or sera from patients with coeliac disease, dermatitis herpetiformis, or hypogammaglobulinaemia as the complement source. Activation by both zymosan and Fill was blocked in 0.01 M EDTA, but not in 0.01 M EGTA with 0.0025 m magnesium chloride. Zymosan and Fill activated complement in a serum from a patient with an intact alternative pathway but classical pathway haemolytic activity (CH50) of zero. Preferential heat inactivation of the alternative pathway inhibited both zymosan- and Fill-induced activation. Our results confirm that Fill is a strong activator of the alternative pathway. We discuss how gluten enteropathy might be initiated by complement.

[Refractory sprue--precursor lesion of enteropathy type T-cell lymphoma--a clinicopathological case report]

INTRODUCTION

Refractory sprue is characterised by distinctive morphologic alterations and the emergence of clonal intraepithelial lymphocytes.

AIM

In this case report the authors emphasize the importance of histopathology in the diagnosis of refractory sprue.

METHODS

The sequential biopsies from this patient have been investigated with routine histology, immunohistochemistry and molecular genetics for T-cell clonality analysis.

RESULTS

The severely cachectic patient presenting with malabsorption syndrome has been diagnosed with celiac disease through a duodenal biopsy, and the CD8 negativity of the intraepithelial lymphocytes suggested the possible diagnosis of refractory sprue. Azathioprine and glucocorticoid therapy was administered due to the failed jejunal feeding and gluten-free diet, resulting in clinically complete, morphologically partial remission. Intestinal T-cell lymphoma developed in the ileocecal region within two years after the first clinical presentation.

DISCUSSION

Refractory sprue and the enteropathy-type T-cell lymphoma constitute a disease spectrum. The reported case shows how a simple method can provide crucial information in the diagnosis of refractory sprue.