Complete recovery of intestinal mucosa occurs very rarely in adult coeliac patients despite adherence to gluten-free diet

Persistent duodenal intraepithelial lymphocytosis despite a long-term strict gluten-free diet in celiac disease

OBJECTIVES

In celiac disease, complete histological normalization of the small-intestinal mucosa occurs in only 8-20% of adult patients after commencing a gluten-free diet. Intraepithelial lymphocytosis may persist for years while villous morphology normalizes. Factors contributing to this and the clinical relevance of persistent intraepithelial lymphocytosis were here investigated.

METHODS

Altogether 177 adult celiac disease patients adhering to a long-term strict gluten-free diet were enrolled. Co-morbidities, ongoing medications, and consumption of oats and wheat-starch were recorded. Small-bowel morphology and intraepithelial lymphocyte count as well as laboratory parameters of malabsorption were evaluated. Gastrointestinal symptoms and psychological well-being were measured by structured questionnaires.

RESULTS

In all, 170 (96%) out of the 177 patients evinced normal villous architecture and 7 (4%) villous atrophy. Among patients with normal villous structure, 96 (56%) had persistent intraepithelial lymphocytosis and 74 (44%) completely normal small-intestinal mucosa. Consumption of oats was the only factor contributing to the persistent intraepithelial lymphocytosis. Co-morbidities, Helicobacter pylori gastritis, drugs, or wheat-starch in the diet had no effect. The clinical outcome of the patients with persistent intraepithelial lymphocytosis was good, since no signs of malabsorption, excess malignancies, increase in gastrointestinal symptoms, or impaired quality of life were associated with it when compared to subjects with completely normal mucosa. The only outcome found in this study was a significantly lower, although normal villous height-crypt depth ratio among the patients with persistent intraepithelial lymphocytosis as compared to those with completely normal mucosa.

CONCLUSIONS

Despite excellent villous recovery in this study, persistent intraepithelial lymphocytosis was still common among celiac disease patients on a long-term strict gluten-free diet. Consumption of oats was associated with persistent duodenal lymphocytosis and this calls for further investigations. The prognosis of patients with persistent intraepithelial lymphocytosis seems to be good while adhering to a gluten-free diet for a mean of 11 years.

Histopathology of celiac disease

Small bowel biopsy remains the gold standard for diagnosing celiac disease (CD). Intraepithelial lymphocytosis in the context of villous atrophy is considered a characteristic histologic finding of CD. However, studies have also indicated that the detection of intraepithelial lymphocytosis in the absence of villous atrophy is not specific for CD, having been documented in other small intestinal disorders. This review summarizes key aspects regarding the histopathologic assessment, impact of the site and number of small bowel biopsy samples on diagnosis, old and emerging classifications, and benefit of standardized pathology report in the diagnostic workup of CD.

Nondietary therapies for celiac disease

Currently, the only available therapy for celiac disease is strict lifelong adherence to a gluten-free diet (GFD). Although safe and effective, the GFD is not ideal. It is frequently expensive, of limited nutritional value, and not readily available in many countries. Consequently, a need exists for novel, nondietary therapies for celiac disease. Based on the current understanding of celiac disease pathogenesis, several potential targets of therapeutic intervention exist. These novel strategies provide promise of alternative, adjunctive treatment options but also raise important questions regarding safety, efficacy, and monitoring of long-term treatment effect.

Celiac disease in elderly adults: clinical, serological, and histological characteristics and the effect of a gluten-free diet

OBJECTIVES

To compare celiac disease (CD) in older and younger adults and to assess the effects of a gluten-free diet (GFD).

DESIGN

Retrospective retrieval of information prospectively entered into a structured database.

SETTING

CD clinic, University and Spedali Civili, Brescia, Italy.

PARTICIPANTS

Two cohorts were identified (older, Group A, n = 59, >65; younger, Group B, n = 1,166, 18-64), and Group B was subgrouped (B1, n = 600, 18-34; B2, n = 440, 35-49; and B3, n = 26, 50-64).

MEASUREMENTS

Clinical, serological, and histological characteristics of individuals with CD studied before and during a GFD.

RESULTS

At presentation, weight loss (37% vs 21%, P = .005) and dyspepsia (22% vs 12%, P = .04) were more frequent in older than younger participants. Incidence at diagnosis of non-Hodgkin's lymphoma (NHL) was much higher in older (5%) than younger participants (0.3%, P = .003). Prevalence of osteoporosis was 67% in older and 14% in younger male participants and 70% in older and 9% in younger female participants ( P < .001). During treatment, adherence to a GFD was 90%, normal villous structure was reconstituted, and t-transglutaminase antibodies were negative in 80% of older and younger participants. Lumbar-sacral and femoral T scores increased significantly during a GFD in pooled results of 48 older and younger participants studied before and during GFD.

CONCLUSION

NHL is already present at CD diagnosis in most cases in individuals aged 50 and older, emphasizing the importance of early diagnosis. Older and younger individuals are equally adherent and equally benefit from a GFD, indicating that older age is not a barrier to dietary treatment.

Celiac disease

Celiac disease is common, affecting approximately 1 in 100 people, yet it remains underdiagnosed. This article reviews our current understanding of celiac disease, diagnosis, and common pitfalls. Although the cornerstone of treatment is a gluten-free diet, some patients may still have persisting symptoms and warrant further investigations.

Small bowel endoscopy and coeliac disease

Coeliac disease (CD) is a gluten-responsive, chronic inflammatory enteropathy that shares many features with classical autoimmune diseases. Coeliac disease affects about 1-2% of Caucasians, North Africans and Asians who possess the necessary susceptibility genes encoding HLA DQ2 or HLA DQ8. It is not only unique among the autoimmune diseases in that the precise trigger (gluten from wheat, rye and barley) has been identified, but also in that it has lent itself well to advancements in endoscopic imaging. Since its introduction, flexible endoscopy has allowed tissue to be collected from the small bowel with relative ease and safety, and recently has facilitated direct imaging and sampling of the entire small intestine. It is now fifty years since the Crosby capsule first allowed clinicians the ability to non-surgically biopsy the small bowel leading to an enhanced diagnosis of coeliac disease. The introduction of wireless video capsule endoscopy (VCE), small bowel enteroscopy and in particular double balloon enteroscopy (DBE), have expedited the accurate diagnosis of coeliac disease and its more serious complications such as small bowel adenocarcinoma, refractory coeliac disease type II (RCDII) and enteropathy associated T cell lymphoma (EATL).

No evidence of circulating autoantibodies against osteoprotegerin in patients with celiac disease

AIM: To investigate risk factors for low bone mineral density (BMD) in celiac disease (CD) patients, focusing on circulating autoantibodies against osteoprotegerin (OPG).

METHODS: Seventy asymptomatic CD adult patients on gluten-free diet (GFD) and harbouring persistent negative CD-related serology were recruited. Conventional risk factors for osteoporosis (e.g., age, sex, menopausal status, history of fractures, smoke, and body mass index) were checked and BMD was assessed by dual energy X ray absorptiometry. Serum calcium and parathyroid hormone (PTH) levels were evaluated. Thirty-eight patients underwent repeat duodenal biopsy. Serum samples from a selected sub-group of 30 patients, who were also typed for human leukocyte antigen (HLA) DQ2 and DQ8 haplotype, were incubated with homodimeric recombinant human OPG and tested by western blotting with an anti-OPG antibody after immunoprecipitation.

RESULTS: Despite persistent negative CD-related serology and strict adherence to GFD, 49 out of the 70 (74%) patients displayed low BMD. Among these patients, 13 (24%) showed osteoporosis and 36 (76%) osteopenia. With the exception of age, conventional risk factors for osteoporosis did not differ between patients with normal and low BMD. Circulating serum calcium and PTH levels were normal in all patients. Duodenal mucosa healing was found in 31 (82%) out of 38 patients who underwent repeat duodenal biopsy with 20 (64%) still displaying low BMD. The remaining 7 patients had an incomplete normalization of duodenal mucosa with 6 (84%) showing low BMD. No evidence of circulating antibodies against OPG was found in the serum of 30 celiac patients who were tested for, independent of BMD, duodenal histology, and HLA status.

CONCLUSION: If any, the role of circulating autoantibodies against OPG in the pathogenesis of bone derangement in patients with CD is not a major one.

High tissue-transglutaminase antibody level predicts small intestinal villous atrophy in adult patients at high risk of celiac disease

BACKGROUND

Duodenal biopsy may be unnecessary to confirm celiac disease in patients with high tissue-transglutaminase antibody level.

AIMS

To define a cut-off value of tissue-transglutaminase antibody with high positive likelihood ratio for duodenal atrophy in patients with suspected celiac disease.

METHODS

We retrospectively identified 945 patients with suspected celiac disease and classified according to the method used for tissue-transglutaminase antibody assay: Group A (n=393, Eu-tTG® Eurospital), Group B (n=263; Eu-tTG® Eurospital) and Group C (n=289; Celikey® Phadia). Duodenal histology was graded according to Marsh. Sensitivity, specificity, and positive likelihood ratio were used to evaluate cut-off points of tissue-transglutaminase antibody as predictor of villous atrophy.

RESULTS

100% specificity and ∞ positive likelihood ratio for duodenal atrophy was observed at a cut-off value of tissue-transglutaminase antibody 5 times higher than the upper limit of normal. CD diagnosis was confirmed by concordance with antiendomysial antibodies, and by reduction of t-TG titre in all patients and improvement of duodenal histology in 80% during gluten-free diet.

CONCLUSIONS

Tissue-transglutaminase antibody level 5-folds the upper limit of normal is 100% specific for duodenal atrophy and using this cut-off biopsy could by avoided in 1/3 of patients. Diagnostic criteria of celiac disease in adults need revision.

Review article: coeliac disease, new approaches to therapy

BACKGROUND

Coeliac disease is managed by life-long gluten withdrawal from the diet. However, strict adherence to a gluten-free diet is difficult and is not always effective. Novel therapeutic approaches are needed to supplement or even replace the dietary treatment.

AIM

To review recent advances in new therapeutic options for coeliac disease.

METHODS

A literature search was performed on MEDLINE, EMBASE, Web of Science, Scopus, DDW.org and ClinicalTrials.gov for English articles and abstracts. The search terms used included, but not limited to, 'Celiac disease', 'new', 'novel', 'Advances', 'alternatives' and 'Drug therapy'. The cited articles were selected based on the relevancy to the review objective.

RESULTS

Several new therapeutic approaches for coeliac disease are currently under development by targeting its underlying pathogenesis. Alternative therapies range from reproduction of harmless wheat strains to immunomodulatory approaches. Some of these therapies such as enzymatic cleavage of gluten and permeability inhibitors have shown promise in clinical studies.

CONCLUSIONS

Gluten-free diet is still the only practical treatment for patients with coeliac disease. Novel strategies provide promise of alternative adjunctive approaches to diet restriction alone for patients with this disorder.

Origin and immunophenotype of aberrant IEL in RCDII patients

OBJECTIVES

Aberrant intra-epithelial lymphocytes (IELs) are the hallmark of refractory coeliac disease type II RCDII and considered a premalignant cell population from which aggressive enteropathy-associated T cell lymphoma (EATL) can evolve. The aim of this study was to gain further insight in the origin and characteristics of aberrant IELs by analysing T-cell receptor (TCR) rearrangements, and by immunophenotypic analysis of aberrant IELs.

DESIGN

Duodenal biopsies from 18 RCDII patients and three RCDII cell lines were analysed for the presence of TCR delta, gamma, and beta rearrangements. In addition, IELs isolated from biopsies derived from RCDII patients were phenotypically analysed.

RESULTS

Aberrant IELs showed an upregulated expression of granzyme B and decreased expression of PCNA. TCR rearrangements in the aberrant IEL population in biopsies of RCDII patients were heterogenic, which is most likely due to a variation in maturity. Similarly, RCDII cell lines displayed a heterogenic TCR rearrangement pattern.

CONCLUSION

Aberrant IELs originate from deranged immature T lymphocytes and display clear differentiation to a cytotoxic phenotype. Aberrant IELs displayed different stages of maturity between RCDII patients, of which only the patients harbouring the most mature aberrant IEL population developed an EATL.

Slow gallbladder emptying reverts to normal but small intestinal transit of a physiological meal remains slow in celiac patients during gluten-free diet

BACKGROUND

Alterations of small intestinal transit and gallbladder (GB) motility have been reported in celiac disease (CD) in studies involving, in most cases, non-physiological experimental conditions and artificial stimuli to motility. Our aims were to quantitate non-invasively small intestinal transit time and GB emptying during administration of a physiological and palatable solid meal, and to assess the effect of gluten-free diet (GFD).

METHODS

We simultaneously measured mouth-to-cecum transit time (MCTT) using a validated H(2) breath test, and GB motility using ultrasonography. We studied CD patients before (n = 19) and during (n = 14) GFD, and healthy volunteers (n = 24) following administration of a physiological solid meal (Kcal 539).

KEY RESULTS

Mouth-to-cecum transit time was more prolonged in CD (mean ± SEM: 235 ± 96 min) than in controls (169 ± 65 min, P = 0.0039). The GB fasting volume and postprandial residual volume were significantly higher in CD than in controls, and GB emptying constant was slower in CD than in controls. During GFD, GB emptying reverted to normal, but MCTT remained unchanged (229 ± 69 min) and more prolonged in CD than in controls (P = 0.0139). During GFD, duodenal infiltration with lymphocytes and mast cells persisted higher than that in controls, and the number of mast cells lying in proximity of nervous endings did not change.

CONCLUSIONS & INFERENCES

Slow postprandial MCTT in response to a physiological meal does not revert to normal during GFD, an effect mirroring incomplete histopathologic recovery.

Safety, tolerability, and activity of ALV003: results from two phase 1 single, escalating-dose clinical trials

BACKGROUND

Celiac disease is the most common hereditary autoimmune disease in humans. The only treatment option for non-refractory celiac disease patients is adherence to a strict life-long gluten-free diet, which often fails to normalize small bowel histology. ALV003 is a mixture of two proteases that degrades gluten and is in clinical development as an oral therapy for patients with celiac disease.

AIMS

The safety, tolerability, and activity of ALV003 were assessed in two phase 1 clinical trials.

METHODS

In study 1 (N = 28) the study drug was administered in the fasted state; in study 2 (N = 53) the study drug was administered together with a gluten-containing meal. Both studies were single-dose, single-blind, placebo-controlled, cross-over trials. ALV003 was dosed at escalating dose levels by cohort (100, 300, 900, and 1,800 mg) and gastric samples were aspirated using a nasogastric tube. Adverse events, serum drug levels, and anti-drug antibody titers were measured. Gastric samples were assessed for ALV003 enzymatic activity over time (gastric pharmacokinetics) and gluten degradation (gastric pharmacodynamics).

RESULTS

All doses were well tolerated, and no serious adverse events or allergic reactions were observed. Gastric aspirates collected 30 min following a meal showed that 100 and 300 mg ALV003 degraded 75 ± 10% (N = 8) and 88 ± 5% (N = 8), respectively, of one gram of wheat bread gluten.

CONCLUSIONS

ALV003 is an orally active protease that appears to be stable in the fed stomach and degrades dietary gluten in this compartment. Single doses of oral ALV003 were not associated with serious adverse reactions.

Non-dietary therapeutic clinical trials in coeliac disease

Coeliac disease is a permanent immunological intolerance to gluten proteins in genetically predisposed individuals. The only management is life-long strict adherence to a gluten-free diet. Unfortunately, compliance with gluten-free diet is very difficult in practice due to the widespread presence of gluten in Western diets. For this reason, about 50% of coeliacs following a gluten-free diet continue to suffer from symptoms and present with autoantibodies and/or villous atrophy while on a gluten-free diet. It is therefore important to explore new therapies to improve the management of coeliac disease. To date, five experimental therapies have been tested in randomized and controlled clinical trials. Larazotide acetate reduces the para-cellular passage of gluten to the lamina propria by preventing the opening of intercellular tight junctions. The endopeptidases ALV003 and AN-PEP break down gluten to produce less or non-toxic peptide fragments. A therapeutic vaccine is being tested with the aim of developing gluten tolerance. Finally, infection with the nematode Necator americanus and treatment with the CCR9 antagonist Traficet-EN have also been reported. While substantial progress has been made in the last few years, it is important to remember that all these investigational therapies are in research stage and are generally being considered as "adjunctive" therapies to the gluten-free diet and not as substitutes of the gluten-free diet at this point in time.

Capsule endoscopy in nonresponsive celiac disease

BACKGROUND

Nonresponsive celiac disease (CD) is defined by persistent or recurrent symptoms, common after treatment with a gluten-free diet (GFD).

OBJECTIVE

To evaluate the utility of capsule endoscopy (CE) in nonresponsive CD.

DESIGN

Case-control study.

SETTING

Tertiary-care center.

PATIENTS

Forty-two consecutive patients with nonresponsive CD and 84 age- and sex-matched CD-free controls who underwent CE were included. In addition, capsules taken after treatment with a GFD were retrospectively evaluated in 30 patients with uncomplicated CD.

INTERVENTION

CE.

MAIN OUTCOME MEASUREMENTS

Diagnostic accuracy of CE for the detection of mucosal abnormalities in nonresponsive CD.

RESULTS

Macroscopic features of villous atrophy were detected in 13 of 42 patients (31%) with nonresponsive CD compared with none among 84 CD-free controls and 14 of 30 patients (47%) with uncomplicated CD. Among nonresponsive CD cases, the overall sensitivity and specificity of CE for the detection of any degree of villous atrophy as graded by histology were 56% and 85%, respectively. Single or multiple erosions/ulcerations of the gut were observed in 19% of nonresponsive CD patients, 18% of CD-free controls, and 31% of patients with uncomplicated CD (P = .35). The presence of erosions/ulcerations was associated with increased aspirin/nonsteroidal anti-inflammatory drug use in nonresponsive CD (P =.05). Two severe complications (ulcerative jejunitis and adenocarcinoma) were detected by CE in nonresponsive CD.

LIMITATIONS

Single-center, retrospective study.

CONCLUSIONS

Mucosal abnormalities were observed by CE in patients with both nonresponsive CD and uncomplicated CD. CE can detect severe complications in patients with nonresponsive CD.

Small- bowel mucosal changes and antibody responses after low- and moderate-dose gluten challenge in celiac disease

BACKGROUND

Due to the restrictive nature of a gluten-free diet, celiac patients are looking for alternative therapies. While drug-development programs include gluten challenges, knowledge regarding the duration of gluten challenge and gluten dosage is insufficient.We challenged adult celiac patients with gluten with a view to assessing the amount needed to cause some small-bowel mucosal deterioration.

METHODS

Twenty-five celiac disease adults were challenged with low (1-3 g) or moderate (3-5g) doses of gluten daily for 12 weeks. Symptoms, small-bowel morphology, densities of CD3+ intraepithelial lymphocytes (IELs) and celiac serology were determined.

RESULTS

Both moderate and low amounts of gluten induced small-bowel morphological damage in 67% of celiac patients. Moderate gluten doses also triggered mucosal inflammation and more gastrointestinal symptoms leading to premature withdrawals in seven cases. In 22% of those who developed significant small- intestinal damage, symptoms remained absent. Celiac antibodies seroconverted in 43% of the patients.

CONCLUSIONS

Low amounts of gluten can also cause significant mucosal deterioration in the majority of the patients. As there are always some celiac disease patients who will not respond within these conditions, sample sizes must be sufficiently large to attain to statistical power in analysis.

Bio-physical characteristics of gastrointestinal mucosa of celiac patients: comparison with control subjects and effect of gluten free diet-

Background

Intestinal mucosa is leaky in celiac disease (CD), and this alteration may involve changes in hydrophobicity of the mucus surface barrier in addition to alteration of the epithelial barrier. The aims of our study were i) to compare duodenal hydrophobicity as an index of mucus barrier integrity in CD patients studied before (n = 38) and during gluten- free diet (GFD, n = 68), and in control subjects (n = 90), and ii) to check for regional differences of hydrophobicity in the gastro-intestinal tract.

Methods

Hydrophobicity was assessed by measurement of contact angle (CA) (Rame Hart 100/10 goniometer) generated by a drop of water placed on intestinal mucosal biopsies.

Results

CA (mean ± SD) of distal duodenum was significantly lower in CD patients (56° ± 10°)) than in control subjects (69° ± 9°, p < 0.0001), and persisted abnormal in patients studied during gluten free diet (56° ± 9°; p < 0.005). CA was significantly higher (62° ± 9°) in histologically normal duodenal biopsies than in biopsies with Marsh 1-2 (58° ± 10°; p < 0.02) and Marsh 3 lesions (57° ± 10°; p < 0.02) in pooled results of all patients and controls studied. The order of hydrofobicity along the gastrointestinal tract in control subjects follows the pattern: gastric antrum > corpus > rectum > duodenum > oesophagus > ileum.

Conclusions

We conclude that the hydrophobicity of duodenal mucous layer is reduced in CD patients, and that the resulting decreased capacity to repel luminal contents may contribute to the increased intestinal permeability of CD. This alteration mirrors the severity of the mucosal lesions and is not completely reverted by gluten-free diet. Intestinal hydrophobicity exhibits regional differences in the human intestinal tract.

The characterization of the repertoire of wheat antigens and peptides involved in the humoral immune responses in patients with gluten sensitivity and Crohn's disease

Intestinal T cells from gluten sensitivity/celiac disease patients respond to a heterogeneous array of peptides. Our study extended this heterogeneity to humoral immune response to various wheat proteins and peptides in patients with gluten sensitivity or Crohn's disease. IgG and IgA antibodies in sera from those patients and healthy control subjects were measured against an array of wheat antigens and peptides. In gluten-sensitive patients, IgG reacted most against transglutaminase, prodynorphin, wheat extract, and α-, γ-, and ω-gliadin; IgA reacted most against wheat then transglutaminase, glutenin, and other peptides. In the sera of Crohn's disease patients, IgG reacted most against wheat and wheat germ agglutinin then transglutaminase, prodynorphin, α-, and γ-gliadin; IgA reacted foremost against prodynorphin then transglutaminase and α-gliadin. These results showed a substantial heterogeneity in the magnitude of IgG and IgA response against various wheat antigens and peptides. Measurements of IgG and IgA antibodies against such an array of wheat peptides and antigens can enhance the sensitivity and specificity of serological assays for gluten sensitivity and celiac disease and may also detect silent celiac disease or its overlap with inflammatory bowel disease.

Celiac disease diagnosis and management: a 46-year-old woman with anemia

Celiac disease is one of the most prevalent autoimmune gastrointestinal disorders, but as the case of Ms J illustrates, diagnosis is often delayed or missed. Based on serologic studies, the prevalence of celiac disease in many populations is estimated to be approximately 1% and has been increasing steadily over the last 50 years. Evaluation for celiac disease is generally straightforward and uses commonly available serologic tests; however, the signs and symptoms of celiac disease are nonspecific and highly heterogeneous, making diagnosis difficult. Although celiac disease is often considered a mild disorder treatable with simple dietary changes, in reality celiac disease imparts considerable risks, including reduced bone mineral density, impaired quality of life, and increased overall mortality. In addition, a gluten-free diet is highly burdensome and can profoundly affect patients and their families. For these reasons, care of individuals with celiac disease requires prompt diagnosis and ongoing multidisciplinary management.

Recent advances in celiac disease

Celiac disease now affects about one person in a hundred in Europe and North America. In this review, we consider a number of important and exciting recent developments, such as clinical associations, HLA-DQ2 and HLA-DQ8 predispositions, the concept of potential celiac disease, the use of new imaging/endoscopy techniques, and the development of refractory disease. This review will be of use to all internists, pediatricians and gastroenterologists.

What is the use of biopsy and antibodies in coeliac disease diagnosis?

The advent of highly sensitive and specific serological markers has led to some protagonists proposing that coeliac disease can be diagnosed without the need for a biopsy. However, this is an area of controversy. Lack of consensus about diagnostic degrees of histological change, paucity of symptoms, antibody-negative disease and immunodeficiency can make diagnosis difficult even with a biopsy. Conversely, an argument can be put forward for a 'no biopsy' approach based on the large number of patients with typical symptoms and positive serology who experience a diagnostic delay. In addition, endoscopy is not without discomfort. This article discusses the use of antibodies and duodenal biopsy within this context. Finally, we propose a pragmatic diagnostic algorithm for clinicians to use when investigating patients for coeliac disease.

Recent advances in celiac disease

Celiac disease now affects about one person in a hundred in Europe and North America. In this review, we consider a number of important and exciting recent developments, such as clinical associations, HLA-DQ2 and HLA-DQ8 predispositions, the concept of potential celiac disease, the use of new imaging/endoscopy techniques, and the development of refractory disease. This review will be of use to all internists, pediatricians and gastroenterologists.

Morphometric evaluation of duodenal biopsies in celiac disease

OBJECTIVES

The Marsh classification is a semiquantitative method for the diagnosis and monitoring of changes in duodenal biopsies in celiac disease. We have explored the possibility that quantitative changes in villous area and crypt length (morphometry) may provide better information on changes in duodenal morphology, particularly after the introduction of a gluten-free diet.

METHODS

We measured villous height, apical and basal villous widths, and crypt length in 57 adults with celiac disease and 83 control subjects. Villous area was calculated as a trapezoid approximation. Serial changes in villous area and crypt length were determined at regular intervals for up to 4 years after the introduction of a gluten-free diet. Morphometric changes were also correlated with Marsh grade, self-reported adherence to a gluten-free diet, and changes in celiac serology.

RESULTS

The gluten-free diet resulted in a progressive increase in villous area and a progressive decrease in crypt length. Morphometric improvement reached a plateau after 6-12 months with mean villous area attaining a value approximately half that of control subjects. Morphometric data were more sensitive than Marsh grade. Improvement in morphometric indices was significantly associated with the disappearance of anti-endomysial IgA antibody but not with dietary compliance.

CONCLUSIONS

Morphometry is a sensitive way to document changes in duodenal biopsies in celiac disease. In adults treated with a gluten-free diet, it is uncommon for villous area to return to values observed in control subjects, but morphometric improvement is associated with the disappearance of anti-endomysial IgA antibody.

Five year time course of celiac disease serology during gluten free diet: results of a community based "CD-Watch" program

BACKGROUND

Little information is available on the effect of a follow-up strategy in celiac disease patients during gluten-free diet.

AIMS

To assess 5 year time course of t-transglutaminase antibodies (t-TG) in celiac disease patients enrolled in a community based follow-up program.

METHODS

Annual t-TG testing and periodical clinic visit in 2245 patients.

RESULTS

Proportion of patients with negative t-TG progressively increased from 83% to 93% during the 5-year follow-up: poor adherence to gluten-free diet (HR 4.764), long duration of gluten-free diet (HR 0.929) and female gender (HR 1.472) were independently associated with serological outcome. In individual patients, 69% tested t-TG "persistently negative", 1% "persistently positive" and 30% "intermittently negative or positive". By applying mathematical modelling to t-TG conversion rates observed in this latter group at beginning and end of the follow-up program, the predicted proportion of t-TG negative population increased from 90% to 95% over 5 years.

CONCLUSIONS

Time-course of t-TG serology in the community fluctuates in 1/3 of celiac disease patients suggesting inconstant adherence to gluten-free diet and need of follow-up strategy. Periodical serological and clinical follow-up is a viable and efficacious strategy to promote adherence to gluten-free diet as inferred from time-course of t-TG serology.

Comprehensive, quantitative mapping of T cell epitopes in gluten in celiac disease

Celiac disease is a genetic condition that results in a debilitating immune reaction in the gut to antigens in grain. The antigenic peptides recognized by the T cells that cause this disease are incompletely defined. Our understanding of the epitopes of pathogenic CD4(+ )T cells is based primarily on responses shown by intestinal T-cells in vitro to hydrolysates or polypeptides of gluten, the causative antigen. A protease-resistant 33-amino acid peptide from wheat alpha-gliadin is the immunodominant antigen, but little is known about the spectrum of T cell epitopes in rye and barley or the hierarchy of immunodominance and consistency of recognition of T-cell epitopes in vivo. We induced polyclonal gluten-specific T cells in the peripheral blood of celiac patients by feeding them cereal and performed a comprehensive, unbiased analysis of responses to all celiac toxic prolamins, a class of plant storage protein. The peptides that stimulated T cells were the same among patients who ate the same cereal, but were different after wheat, barley and rye ingestion. Unexpectedly, a sequence from omega-gliadin (wheat) and C-hordein (barley) but not alpha-gliadin was immunodominant regardless of the grain consumed. Furthermore, T cells specific for just three peptides accounted for the majority of gluten-specific T cells, and their recognition of gluten peptides was highly redundant. Our findings show that pathogenic T cells in celiac disease show limited diversity, and therefore suggest that peptide-based therapeutics for this disease and potentially other strongly HLA-restricted immune diseases should be possible.

An update in the diagnosis of coeliac disease

Coeliac disease is increasing in prevalence, which is currently estimated at one in 100 of the population and may occur de novo in adults. The diagnosis requires a joint clinicopathological approach; the recommended first-line test is serology with immunoglobulin A (IgA) tissue transglutaminase and IgA endomysial antibodies. These serological tests show high levels of sensitivity and specificity, but biopsy is the gold standard to confirm the diagnosis. It is important that both tests are performed before the introduction of a gluten-free diet. Although the classical histopathology changes of coeliac disease with partial or total villous atrophy are well recognized, the pathology classification of coeliac disease is changing, with recognition that coeliac disease may show minimal pathology (normal architecture and an intraepithelial lymphocyte count/100 enterocytes ≥ 25). This entity is also described as lymphocytic duodenosis, and recommendation of follow-up serology testing is paramount in this condition. Follow-up of patients with coeliac disease is warranted, as normal serology does not predict mucosal recovery. Failure to heal predicts risk of progression to refractory coeliac disease and malignancies. Refractory coeliac disease occurs in 1-2% of patients and this diagnosis requires a combined clinical and histopathology approach with immunocytochemistry.

Mucosal recovery and mortality in adults with celiac disease after treatment with a gluten-free diet

OBJECTIVES

Clinical response is typically observed in most adults with celiac disease (CD) after treatment with a gluten-free diet (GFD). The rate of mucosal recovery is less certain. The aims of this study were (1) to estimate the rate of mucosal recovery after GFD in a cohort of adults with CD, and (2) to assess the clinical implications of persistent mucosal damage after GFD.

METHODS

The study group included adults with biopsy-proven CD evaluated at the Mayo Clinic who had duodenal biopsies at diagnosis and at least one follow-up intestinal biopsy to assess mucosal recovery after starting a GFD. The primary outcomes of interest were mucosal recovery and all-cause mortality.

RESULTS

Of 381 adults with biopsy-proven CD, 241 (73% women) had both a diagnostic and follow-up biopsy available for re-review. Among these 241, the Kaplan-Meier rate of confirmed mucosal recovery at 2 years following diagnosis was 34% (95% confidence interval (CI): 27-40%), and at 5 years was 66% (95% CI: 58-74%). Most patients (82%) had some clinical response to GFD, but it was not a reliable marker of mucosal recovery (P=0.7). Serological response was associated with confirmed mucosal recovery (P=0.01). Poor compliance to GFD (P<0.01), severe CD defined by diarrhea and weight loss (P<0.001), and total villous atrophy at diagnosis (P<0.001) were strongly associated with persistent mucosal damage. There was a trend toward an association between achievement of mucosal recovery and a reduced rate of all-cause mortality (hazard ratio=0.13, 95% CI: 0.02-1.06, P=0.06), adjusted for gender and age.

CONCLUSIONS

Mucosal recovery was absent in a substantial portion of adults with CD after treatment with a GFD. There was a borderline significant association between confirmed mucosal recovery (vs. persistent damage) and reduced mortality independent of age and gender. Systematic follow-up with intestinal biopsies may be advisable in patients diagnosed with CD as adults.

Celiac disease

PURPOSE OF REVIEW

To summarize recent advances in celiac disease published between August 2008 and July 2009.

RECENT FINDINGS

Celiac disease affects nearly 1% of most populations but remains largely unrecognized. In the last year, work has shown that the prevalence of celiac disease has increased dramatically, not simply due to increased detection. Also, undiagnosed celiac disease may be associated with increased mortality. Significant progress has been made in understanding how gliadin peptides can cross the intestinal border and access the immune system. New genetic loci and candidate genes that may contribute to the risk of celiac disease and its overlap with type 1 diabetes mellitus have been identified. Novel deamidated gliadin peptides antibodies have better diagnostic accuracy over native gliadin-based tests. The inclusion of duodenal bulb biopsy specimens may increase the rate of celiac disease detection. The spectrum of celiac disease likely includes a minority of patients with mild enteropathy. A practical seven-item instrument may facilitate standardized evaluation of gluten-free diet adherence. Finally, refractory celiac disease, although rare, is associated with a poor prognosis.

SUMMARY

Celiac disease is a global health problem that requires a multidisciplinary and increasingly cooperative multinational research effort.

The effects of ALV003 pre-digestion of gluten on immune response and symptoms in celiac disease in vivo

Effective treatment of celiac disease is an unmet medical need. A glutenase that destroys immunogenic gluten peptides may be clinically valuable. Twenty patients with celiac disease were randomly assigned to ingest a large gluten meal (16 g daily for 3 days) pre-treated with ALV003, a mixture of highly specific glutenases (n=10), or pre-treated with placebo (n=10). Peripheral blood T-cell IFN-gamma ELISpot responses to gliadin and an immunogenic 33mer and symptoms were assessed. While baseline IFN-gamma ELISpot responses to gliadin and the 33mer were negative in all patients, a significant ELISpot response to gliadin or the 33mer was observed in 6 of 10 patients consuming placebo-treated gluten and 0 of 10 consuming ALV003 pre-treated gluten (p=0.011). Symptoms typically associated with gluten ingestion occurred in both groups and were not significantly reduced by ALV003 pre-treatment. ALV003 pre-treatment can abolish immune responses induced by gluten in patients with celiac disease.