Performing routine follow-up biopsy 1 year after diagnosis does not affect long-term outcomes in coeliac disease

Gluten-Free Diet Adherence Tools for Individuals with Celiac Disease: A Systematic Review and Meta-Analysis of Tools Compared to Laboratory Tests

This systematic review aimed to find the tool that best predicts celiac individuals' adherence to a gluten-free diet (GFD). The Transparent Reporting of Multivariable Prediction Models for Individual Prognosis or Diagnosis (TRIPOD-SRMA) guideline was used for the construction and collection of data from eight scientific databases (PubMed, EMBASE, LILACS, Web of Science, LIVIVO, SCOPUS, Google Scholar, and Proquest) on 16 November 2023. The inclusion criteria were studies involving individuals with celiac disease (CD) who were over 18 years old and on a GFD for at least six months, using a questionnaire to predict adherence to a GFD, and comparing it with laboratory tests (serological tests, gluten immunogenic peptide-GIP, or biopsy). Review articles, book chapters, and studies without sufficient data were excluded. The Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modeling Studies (CHARMS) was used for data collection from the selected primary studies, and their risk of bias and quality was assessed using the Prediction Risk of Bias Assessment Tool (PROBAST). The association between the GFD adherence determined by the tool and laboratory test was assessed using the phi contingency coefficient. The studies included in this review used four different tools to evaluate GFD adherence: BIAGI score, Coeliac Dietary Adherence Test (CDAT), self-report questions, and interviews. The comparison method most often used was biopsy (n = 19; 59.3%), followed by serology (n = 14; 43.7%) and gluten immunogenic peptides (GIPs) (n = 4; 12.5%). There were no significant differences between the interview, self-report, and BIAGI tools used to evaluate GFD adherence. These tools were better associated with GFD adherence than the CDAT. Considering their cost, application time, and prediction capacity, the self-report and BIAGI were the preferred tools for evaluating GFD adherence.

Celiac Disease Affects 1% of Global Population: Who Will Manage All These Patients?

Celiac disease is a common gastrointestinal condition with an estimated global prevalence of up to 1%. Adequate long-term surveillance of patients is imperative to ensure strict adherence to treatment with a gluten-free diet and the ensuing clinical and histologic recovery. Traditionally, this has been accomplished by means of regular on-site attendance at specialist health care facilities, accompanied for most patients by follow-up endoscopic and laboratory tests. However, the rapidly increasing prevalence of celiac disease and the limited health care resources challenge the current centralized and nonindividualized follow-up strategies. The improved noninvasive surveillance tools and online health care services are further changing the landscape of celiac disease management. There is a clear need for more personalized and on-demand follow-up based on early treatment response and patient-related factors associated with long-term prognosis. Additional scientific evidence on the optimal implementation of follow-up for pediatric and adulthood celiac disease is nevertheless called for.

Guidelines for best practices in monitoring established coeliac disease in adult patients

Coeliac disease (CeD) is an immunological disease triggered by the consumption of gluten contained in food in individuals with a genetic predisposition. Diagnosis is based on the presence of small bowel mucosal atrophy and circulating autoantibodies (anti-type 2 transglutaminase antibodies). After diagnosis, patients follow a strict, life-long gluten-free diet. Although the criteria for diagnosis of this disease are well defined, the monitoring phase has been studied less and there is a lack of specific guidelines for this phase. To develop a set of clinical guidelines for CeD monitoring, we followed the Grading of Recommendations Assessment, Development and Evaluation methodology. Statements and recommendations with the level of evidence were developed and approved by the working group, which comprised gastroenterologists, pathologists, dieticians and biostatisticians. The proposed guidelines, endorsed by the North American and European coeliac disease scientific societies, make recommendations for best practices in monitoring patients with CeD based on the available evidence. The evidence level is low for many topics, suggesting that further research in specific aspects of CeD would be valuable. In conclusion, the present guidelines support clinicians in improving CeD treatment and follow-up and highlight novel issues that should be considered in future studies.

Clinical Data Do Not Reliably Predict Duodenal Histology at Follow-up in Celiac Disease: A 13 Center Correlative Study

Validated nonbiopsy methods to assure duodenal mucosal healing in celiac disease are lacking, yet ongoing mucosal injury is associated with anemia, osteoporosis, and lymphoma. Most providers utilize clinical data as surrogates of mucosal status to avoid additional esophagogastroduodenoscopy. The reliability of such surrogates to predict mucosal recovery has been incompletely evaluated. The aim of this study was to rigorously assess patterns of histologic mucosal recovery at follow-up in celiac disease and to correlate findings with clinical data. Gastrointestinal pathologists from 13 centers evaluated initial and follow-up duodenal biopsies from 181 celiac disease patients. Marsh scores and intraepithelial lymphocytes (IELs)/100 enterocytes were assessed blindly. Histology at follow-up was correlated with symptoms, immunoglobulin A anti-tissue transglutaminase titers and gluten-free diet adherence. Fifty-six/181 (31%) patients had persistent villous blunting and 46/181 (25%) patients had just persistently elevated IELs at follow-up, with only 79/181 (44%) patients having complete histologic remission. IEL normalization (82/181; 45%) lagged villous recovery (125/181;69%). In a minority of patients, villous blunting was limited to proximal duodenal biopsies. No correlation was found between Marsh scores and symptoms, normalization of immunoglobulin A anti-tissue transglutaminase serology, or diet adherence. Children showed greater recovery of Marsh score ( P <0.001) and IELs ( P <0.01) than adults. Persistent mucosal injury is common in celiac disease, with discordant villous/IEL normalization. Pathologist awareness of expected findings in celiac disease follow-up biopsies, including their frequent lack of correlation with clinical data, is important for patient management, and has implications for eligibility criteria for therapeutics currently in development.

Persistent villous atrophy predicts development of complications and mortality in adult patients with coeliac disease: a multicentre longitudinal cohort study and development of a score to identify high-risk patients

OBJECTIVE

Persistent villous atrophy (pVA) in coeliac disease (CD) despite a gluten-free diet (GFD) has unclear meaning. We aimed to (i) study the relationship between pVA and long-term outcomes and (ii) develop a score to identify patients at risk of pVA.

DESIGN

This is a multicentre retrospective-prospective study consisting of a study cohort (cohort 1) and an external validation cohort (cohort 2) of patients with biopsy-proven CD diagnosed between 2000 and 2021. Cohort 1 was used to (i) compare long-term outcomes between patients with and without pVA (Marsh ≥3a) at follow-up biopsy and (ii) to develop a score to evaluate the risk of pVA, which was validated in cohort 2.

RESULTS

Of 2211 patients, 694 (31%) underwent follow-up duodenal biopsy and were included in the study cohort (491F, 44±16 years). 157/694 (23%) had pVA. Risk of complications (HR 9.53, 95% CI 4.77 to 19.04, p<0.001) and mortality (HR 2.93, 95% CI 1.43 to 6.02, p<0.01) were increased in patients with pVA. A 5-point score was developed and externally validated (receiver operating characteristic area under the curve 0.78, 95% CI 0.68 to 0.89) to stratify patients by risk of pVA: low (0-1 points, 5% pVA), intermediate (2 points, 16% pVA) and high (3-5 points, 73% pVA). Predictors for pVA used in the score were age at diagnosis ≥45 years (OR 2.01, 95% CI 1.21 to 3.34, p<0.01), classical pattern of CD (OR 2.14, 95% CI 1.28 to 3.58, p<0.01), lack of clinical response to GFD (OR 2.40, 95% CI 1.43 to 4.01, p<0.001) and poor GFD adherence (OR 48.9, 95% CI 26.1 to 91.8, p<0.001).

CONCLUSIONS

Risk of complications and mortality were increased in patients with pVA. We developed a score to identify patients at risk of pVA and in need of histological reassessment and closer follow-up.

Guidelines of the Italian societies of gastroenterology on the diagnosis and management of coeliac disease and dermatitis herpetiformis

INTRODUCTION

Coeliac disease and dermatitis herpetiformis are immune-mediated diseases triggered by the consumption of gluten in genetically predisposed individuals. These guidelines were developed to provide general practitioners, paediatricians, gastroenterologists, and other clinicians with an overview on the diagnosis, management and follow-up of coeliac patients and those with dermatitis herpetiformis.

METHODS

Guidelines were developed by the Italian Societies of Gastroenterology. Following a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the certainty of the evidence. Statements and recommendations were developed by working groups consisting of gastroenterologists and a paediatrician with expertise in this field.

RESULTS

These guidelines provide a practical guidance for the diagnosis, management and follow-up of coeliac patients and dermatitis herpetiformis in children and adults, both in primary care and in specialist settings. We developed four sections on diagnosis, gluten-free diet, follow-up and risk of complications in adults, one section focused on diagnosis and follow-up in children and one on the diagnosis and management of dermatitis herpetiformis.

CONCLUSIONS

These guidelines may support clinicians to improve the diagnosis and management of patients with coeliac disease.

Sex–Gender Differences in Adult Coeliac Disease at Diagnosis and Gluten-Free-Diet Follow-Up

Coeliac disease (CD) is an immune-mediated enteropathy triggered by gluten ingestion. At CD diagnosis, gender differences have been previously reported, but data regarding follow-up are scant. We investigated gender differences in CD adult patients both at the time of diagnosis and at follow-up after the start of the gluten-free diet (GFD). This is a longitudinal cohort study on adult CD patients diagnosed between 2008 and 2019. Clinical, biochemical, and histological data were assessed and compared between males and females. At diagnosis, female gender was significantly associated with signs of malabsorption (OR 3.39; 95% CI: 1.4–7.9), longer duration of symptoms and/or signs before the diagnosis (OR 3.39; 95% CI: 1.5–7.5), heartburn (OR 2.99; 95% CI: 1.1–8.0), dyspepsia (OR 2.70; 95% CI: 1.1–6.5), nausea/vomit (OR 3.53; 95% CI: 1.1–10.9), and constipation (OR 4.84; 95% CI: 1.2–19.6) and less frequently associated to higher body mass index (OR 0.88; 95% CI: 0.8–0.9) and osteopenia/osteoporosis (OR 0.30; 95% CI: 0.1–0.7) compared to male patients. After 12–30 months, females presented lower median BMI, performed less frequently histological control, and had more frequently anaemia and hypoferritinaemia compared to males. No significant differences concerning the presence of gastrointestinal symptoms, adherence to GFD, and Marsh score were found. Gender differences found at CD diagnosis mostly disappear at the follow-up, showing that these differences can be solved over time.

Review article: Follow-up of coeliac disease

Coeliac disease is a lifelong immune-mediated enteropathy with systemic features associated with increased morbidity and modestly increased mortality. Treatment with a strict gluten-free diet improves symptoms and mucosal damage but is not curative and low-level gluten intake is common despite strict attempts at adherence. Regular follow-up after diagnosis is considered best-practice however this is executed poorly in the community with the problem compounded by the paucity of data informing optimal approaches. The aim of dietary treatment is to resolve symptoms, reduce complication risk and improve quality of life. It follows that the goals of monitoring are to assess dietary adherence, monitor disease activity, assess symptoms and screen for complications. Mucosal disease remission is regarded a key measure of treatment success as healing is associated with positive health outcomes. However, persistent villous atrophy is common, even after many years of a gluten-free diet. As the clinical significance of asymptomatic enteropathy is uncertain the role for routine follow-up biopsies remains contentious. Symptomatic non-responsive coeliac disease is common and with systematic follow-up a cause is usually found. Effective models of care involving the gastroenterologist, dietitian and primary care doctor will improve the consistency of long-term management and likely translate into better patient outcomes. Identifying suitable treatment targets linked to long-term health is an important goal.

Risk of Drop-Out from Follow-Up Evaluations for Celiac Disease: Is It Similar for All Patients?

Background: Celiac disease (CD) follow-up is a relatively underevaluated topic. However, correct adherence to follow-up procedures is central to the early recognition of complicated CD and other conditions typically associated with CD. Establishing whether patients at increased risk of complications follow clinicians’ recommendations has multiple repercussions. Methods: We retrospectively analyzed the records of patients consecutively diagnosed with CD in our outpatient clinic between January 2004 and October 2017 to investigate the factors associated with drop-out from follow-up procedures. Results: Among the 578 patients analyzed, 40 (6.9%) dropped out during the first six months and 272 (50.6%) during the observation period. The median time to drop-out was 7.4 years (95% confidence interval: 6.8−8.0). No factors were associated with early drop-out. Instead, age at diagnosis >40 years (40−59 years, p < 0.001; ≥60 years, p = 0.048) and classical clinical presentation (p = 0.016) were significantly associated with a lower risk of later drop-out. Conclusions: Patients at increased risk of complicated CD are more compliant with follow-up procedures than patients at lower risk, despite being prescribed the same controls. These results indirectly support the hypothesis of tailored follow-up strategies, differentiated according to the risk of complications.

Frontiers in Celiac Disease: Where Autoimmunity and Environment Meet

Celiac disease is a chronic, immune-mediated enteropathy driven by dietary gluten found in genetically susceptible hosts. It has a worldwide distribution, is one of the most common autoimmune disorders globally, and is the only autoimmune condition for which the trigger is known. Despite advances in characterizing mechanisms of disease, gaps in understanding of celiac disease pathogenesis remain. A "frontier" concept is considering what moves an HLA-DQ2 or DQ8-positive individual from asymptomatic gluten tolerance to celiac disease manifestation. In this arena, environmental triggers, including age at the time of initial gluten exposure, the occurrence of usual childhood viral infections, and microbiome alterations have emerged as key events in triggering the symptomatic disease. Pathologists play a major role in frontier aspects of celiac disease. This includes the discovery that duodenal mucosal histology in follow-up biopsies does not correlate with ongoing patient symptoms, antitissue transglutaminase antibody titers and diet adherence in celiac disease patients. Further, in light of recent evidence that the detection of monoclonal T-cell populations in formalin-fixed biopsies is not specific for type II refractory celiac disease, pathologists should resist performing such analyses until common causes of "apparent" refractoriness are excluded. The promise of therapies in celiac disease has led to clinical trials targeting many steps in the inflammatory cascade, which depend upon a pathologist's confirmation of the initial diagnosis and evaluation of responses to therapies. As pathologists continue to be active participants in celiac disease research, partnering with other stakeholders, we will continue to impact this important autoimmune disease.

Understanding celiac disease monitoring patterns and outcomes after diagnosis: A multinational, retrospective chart review study

BACKGROUND

Long-term outcomes and monitoring patterns in real-world practice are largely unknown among patients with celiac disease.

AIM

To understand patterns of follow-up and management of patients with celiac disease, and to characterize symptoms and villous atrophy after diagnosis.

METHODS

A retrospective chart review study was performed using medical chart data of patients diagnosed with celiac disease. Three gastroenterology referral centers, with substantial expertise in celiac disease, participated in the United Kingdom, United States, and Norway. Demographic and clinical data were collected from medical charts. Descriptive analyses were conducted on patients with biopsy-confirmed celiac disease, diagnosed between 2008 and 2012, with at least one follow-up visit before December 31, 2017. Patient demographic and clinical characteristics, biopsy/serology tests and results, symptoms, and comorbidities were captured at diagnosis and for each clinic visit occurring within the study period (i.e., before the study end date of December 31, 2017).

RESULTS

A total of 300 patients were included in this study [72% female; mean age at diagnosis: 38.9 years, standard deviation (SD) 17.2]. Patients were followed-up for a mean of 29.9 mo (SD 22.1) and there were, on average, three follow-up visits per patient during the study period. Over two-thirds (68.4%) of patients were recorded as having ongoing gastrointestinal symptoms and 11.0% had ongoing symptoms and enteropathy during follow-up. Approximately 80% of patients were referred to a dietician at least once during the follow-up period. Half (50.0%) of the patients underwent at least one follow-up duodenal biopsy and 36.6% had continued villous atrophy. Patterns of monitoring varied between sites. Biopsies were conducted more frequently in Norway and patients in the United States had a longer follow-up duration.

CONCLUSION

This real-world study demonstrates variable follow-up of patients with celiac disease despite most patients continuing to have abnormal histology and symptoms after diagnosis.

Celiac disease antibody levels reflect duodenal mucosal damage but not clinical symptoms

OBJECTIVES

This study aimed to investigate, in a real-world population, whether the histological and clinical phenotype differ at baseline and during follow-up in patients with high and low CD (celiac disease) antibody titers.

MATERIALS AND METHODS

The study cohort consisted of 96 consecutive patients diagnosed to have CD during the years 2010-2018. The clinical parameters, symptoms and laboratory results were registered and histomorphometry was analyzed from the available duodenal biopsies taken during the primary and follow-up esophageal-gastricduodenoscopies. Patients having immunoglobulin A transglutaminase antibody (tTG-ab) levels above 70 U/mL were classified as high titer patients.

RESULTS

Measured by the villous-crypt ratio, the duodenal mucosa was more severely damaged in the high tTG-ab group than in the low tTG-group at baseline (n = 70, 0.61 ± 0.63 vs. 1.02 ± 0.87, p = .003) and during the follow-up when the patients were on gluten-free diet (n = 27, 1.80 ± 0.72 vs. 2.35 ± 0.64, p = .041). Interestingly, the high tTG-ab group members had fewer gastrointestinal symptoms at baseline than those in the low tTG-ab group (43% vs. 68%, p = .013) but lower vitamin D levels (68 ± 34 nmol/L vs. 88 ± 29 nmol/L, p = .034) and more often microcytosis (28% vs. 10%, p = .040). During the follow-up, these differences were no longer detected.

CONCLUSIONS

At baseline, CD patients with high tTG-ab have more severe duodenum injury and signs of malabsorption but fewer symptoms. After gluten-free diet has been initiated, the mucosal healing in the high tTG-ab group is prolonged, but symptoms and signs of malabsorption recover equally in both groups.

Relationship between Persistent Gastrointestinal Symptoms and Duodenal Histological Findings after Adequate Gluten-Free Diet: A Gray Area of Celiac Disease Management in Adult Patients

A gluten-free diet (GFD) leads to a rapid improvement in gastrointestinal (GI) symptoms, biochemical alterations and duodenal histological damage in the majority of celiac disease (CD) patients. This study aimed to assess the frequency and factors associated with the persistence of GI symptoms/malabsorption signs and their relationship with duodenal histological findings among CD patients on an adequate GFD (mean duration 16 months, range 12-28 months). This longitudinal cohort study included 102 adult CD patients (median age 38.5 years, range 18-76 years, F = 71.6%) diagnosed between 2012 and 2018. A total of 36.3% of the included patients had persistent GI symptoms and/or malabsorption signs (Group 1), while the remaining patients had complete GI well-being without malabsorption signs (Group 2) at the time of histological re-evaluation. The persistence of GI symptoms/signs was associated with a long duration of symptoms/signs before CD diagnosis (≥5 years) (OR 5.3; 95% CI 1.3-21.8) and the presence of constipation at the time of CD diagnosis (OR 7.5; 95% CI 1.3-42) while for other variables, including age at CD diagnosis, sex, duration of GFD, comorbidities, CD serology positivity and severity of duodenal damage at histological re-evaluation, no association was found. According to our results, the persistence of symptoms/signs is not associated with histological findings, and their relationship could be a gray area in CD management.

The role of histopathology in the diagnosis and management of coeliac disease and other malabsorptive conditions

Most absorption of nutrients takes place in the proximal small intestine, and the most common disorders leading to malabsorption are associated with a morphological abnormality in the duodenal mucosa that is appreciable in histological sections of biopsy specimens. Coeliac disease is the most well-known example, causing intraepithelial lymphocytosis, inflammation and villous atrophy in the duodenum. Remarkably similar inflammatory changes can be induced by other processes, including medications, e.g. angiotensin II receptor blockers and immune checkpoint inhibitors, immune dysregulation disorders, e.g. common variable immunodeficiency and autoimmune enteropathy, infections, collagenous sprue, and tropical sprue. However, there are often subtle histological differences from coeliac disease in the type of inflammatory infiltrate, the presence of crypt apoptosis, and the extent and type of inflammation beyond the duodenum. The clinical setting and serological investigation usually allow diagnostic separation, but some cases remain challenging. Histopathology is also important in assessing the response to treatment, such as the change in villous architecture caused by a gluten-free diet, or the response to cessation of a potentially causative medication. This review examines the practical role that histopathology of duodenal biopsy specimens plays in the assessment and management of inflammatory malabsorptive processes of the proximal small intestine, with a particular emphasis on coeliac disease.

Interventions to Increase Adherence to a Gluten Free Diet in Patients with Coeliac Disease: A Scoping Review

Coeliac disease is a chronic inflammatory disorder of the small bowel, characterised by permanent intolerance to gluten. The only current and effective treatment for coeliac disease is a gluten free diet [GFD], however this is challenging for patients to adhere to. The review aims to identify published interventions designed to improve patients’ adherence to a GFD. Ten intervention studies were identified and included within the review; whilst heterogeneous in delivery, all included an educational, behavioural, and practical element. Five interventions significantly improved dietary adherence, these included follow-up appointments, a telephone clinic, an online course, cooking sessions and psychological support. All studies were small and used varied methods to assess adherence. There is a paucity of well-designed interventions to promote dietary adherence, in future more robust methods for ascertaining adherence is needed, we recommend greater inclusion of dietetic assessment and combining more than one method for assessing adherence.

Optimising the follow-up of adult coeliac disease with a clinical-based score to identify patients in need of a histological reassessment: a retrospective single centre study

Follow-up modalities for adult coeliac patients remain controversial. Non-invasive markers to identify coeliac patients on a gluten-free diet (GFD) with persistence of villous atrophy (VA) are still lacking. We aim to develop a score to stratify coeliac patients on a GFD according to their risk of having persistent VA and to tailor follow-up modalities accordingly. The clinical notes of over 700 coeliac patients attending our unit (September 1999-November 2018) were retrospectively examined. A total of 273 patients on a GFD with a histological follow-up performed 12-24 months after diagnosis were selected. We developed a bivariable model based on diet adherence and clinical response evaluated by previously validated methods. A four-level score (0·5, 1·5, 3, 4) was obtained. Patients on a strict GFD and with good clinical conditions (score 4) have a very low risk of persistence of VA (2 (95 % CI 1, 5) %). Conversely, the risk is very high (46 (95 % CI 25, 68) %) in patients with poor adherence to a GFD and unsatisfactory clinical response (score 0·5). A score of 1·5 (poor GFD adherence and persistent well-being) is linked with a high risk (23 (95 % CI 14, 36) %). Risk is intermediate (6 (95 % CI 3, 10) %) in patients scoring 3 (strict GFD and no/partial clinical improvement). Three patients who developed complications belonged to this scenario. Patients at low risk of persistent VA can be followed-up non-invasively, whereas a biopsy should be repeated in those at high/very high risk. Case-by-case evaluation is needed in patients at intermediate risk. Studies on a larger sample size are required to confirm these data.

A Call for Research on the Prognostic Role of Follow-Up Histology in Celiac Disease: A Systematic Review

Background: Convincing evidence is lacking on the benefit of follow-up biopsy in celiac disease. Regardless, achieving mucosal recovery (MR) has remained a desirable goal of therapy. We aimed to conduct a systematic review to determine whether MR is a protective factor and persisting villous atrophy (PVA) has negative consequences on long-term outcomes of celiac disease.

Methods: Seven databases were searched for articles discussing celiac patients subjected to a gluten-free diet who had a follow-up biopsy, and clinical and laboratory characteristics were reported by follow-up histology (MR vs. PVA). Outcomes included clinical symptoms, mortality, malignant tumors, nutritional parameters, and metabolic bone disease. Comparative and descriptive studies were included. Since data proved to be ineligible for meta-analysis, the evidence was synthesized in a systematic review.

Results: Altogether, 31 studies were eligible for systematic review. Persisting symptoms were more frequently associated with PVA than with MR, although a lot of symptom-free patients had PVA and a lot of symptomatic patients achieved MR. PVA might be a risk factor of lymphomas, but mortality and the overall rate of malignant tumors seemed independent of follow-up histology. Patients with PVA tended to develop metabolic bone disease more often, although fracture risk remained similar in the groups except in hip fractures of which PVA was a risk factor. Reports on nutritional markers are only anecdotal.

Conclusions: The limited evidence calls for high-quality prospective cohort studies to be arranged to clarify the exact role of follow-up histology in celiac disease.

The Pros and Cons of Using Oat in a Gluten-Free Diet for Celiac Patients

A therapeutic gluten-free diet often has nutritional limitations. Nutritional qualities such as high protein content, the presence of biologically active and beneficial substances (fiber, beta-glucans, polyunsaturated fatty acids, essential amino acids, antioxidants, vitamins, and minerals), and tolerance by the majority of celiac patients make oat popular for use in gluten-free diet. The health risk of long-time consumption of oat by celiac patients is a matter of debate. The introduction of oat into the diet is only recommended for celiac patients in remission. Furthermore, not every variety of oat is also appropriate for a gluten-free diet. The risk of sensitization and an adverse immunologically mediated reaction is a real threat in some celiac patients. Several unsolved issues still exist which include the following: (1) determination of the susceptibility markers for the subgroup of celiac patients who are at risk because they do not tolerate dietary oat, (2) identification of suitable varieties of oat and estimating the safe dose of oat for the diet, and (3) optimization of methods for detecting the gliadin contamination in raw oat used in a gluten-free diet.

AGA Clinical Practice Update on Diagnosis and Monitoring of Celiac Disease-Changing Utility of Serology and Histologic Measures: Expert Review

PURPOSE

The purpose of this clinical practice update is to define key modalities in the diagnosis and monitoring of celiac disease (CD) in adults as well as in children and adolescents.

METHODS

The recommendations outlined in this expert review are based on available published evidence, including cohort and case-control studies of the diagnostic process as well as controlled and descriptive studies of disease management. Best Practice Advice 1: Serology is a crucial component of the detection and diagnosis of CD, particularly tissue transglutaminase-immunoglobulin A (TG2-IgA), IgA testing, and less frequently, endomysial IgA testing. Best Practice Advice 2: Thorough histological analysis of duodenal biopsies with Marsh classification, counting of lymphocytes per high-power field, and morphometry is important for diagnosis as well as for differential diagnosis. Best Practice Advice 2a: TG2-IgA, at high levels (> ×10 upper normal limit) is a reliable and accurate test for diagnosing active CD. When such a strongly positive TG2-IgA is combined with a positive endomysial antibody in a second blood sample, the positive predictive value for CD is virtually 100%. In adults, esophagogastroduodenoscopy (EGD) and duodenal biopsies may then be performed for purposes of differential diagnosis. Best Practice Advice 3: IgA deficiency is an infrequent but important explanation for why patients with CD may be negative on IgA isotype testing despite strong suspicion. Measuring total IgA levels, IgG deamidated gliadin antibody tests, and TG2-IgG testing in that circumstance is recommended. Best Practice Advice 4: IgG isotype testing for TG2 antibody is not specific in the absence of IgA deficiency. Best Practice Advice 5: In patients found to have CD first by intestinal biopsies, celiac-specific serology should be undertaken as a confirmatory test before initiation of a gluten-free diet (GFD). Best Practice Advice 6: In patients in whom CD is strongly suspected in the face of negative biopsies, TG2-IgA should still be performed and, if positive, repeat biopsies might be considered either at that time or sometime in the future. Best Practice Advice 7: Reduction or avoidance of gluten before diagnostic testing is discouraged, as it may reduce the sensitivity of both serology and biopsy testing. Best Practice Advice 8: When patients have already started on a GFD before diagnosis, we suggest that the patient go back on a normal diet with 3 slices of wheat bread daily preferably for 1 to 3 months before repeat determination of TG2-IgA. Best Practice Advice 9: Determination of HLA-DQ2/DQ8 has a limited role in the diagnosis of CD. Its value is largely related to its negative predictive value to rule out CD in patients who are seronegative in the face of histologic changes, in patients who did not have serologic confirmation at the time of diagnosis, and in those patients with a historic diagnosis of CD; especially as very young children before the introduction of celiac-specific serology.

MANAGEMENT

Best Practice Advice 10: Celiac serology has a guarded role in the detection of continued intestinal injury, in particular as to sensitivity, as negative serology in a treated patient does not guarantee that the intestinal mucosa has healed. Persistently positive serology usually indicates ongoing intestinal damage and gluten exposure. Follow-up serology should be performed 6 and 12 months after diagnosis, and yearly thereafter. Best Practice Advice 11: Patients with persistent or relapsing symptoms, without other obvious explanations for those symptoms, should undergo endoscopic biopsies to determine healing even in the presence of negative TG2-IgA.

Coeliac disease

Coeliac disease is an immune-mediated enteropathy against dietary gluten present in wheat, rye and barley and is one of the most common lifelong food-related disorders worldwide. Coeliac disease is also considered to be a systemic disorder characterized by a variable combination of gluten-related signs and symptoms and disease-specific antibodies in addition to enteropathy. The ingestion of gluten leads to the generation of harmful gluten peptides, which, in predisposed individuals, can induce adaptive and innate immune responses. The clinical presentation is extremely variable; patients may have severe gastrointestinal symptoms and malabsorption, extraintestinal symptoms or have no symptoms at all. Owing to the multifaceted clinical presentation, diagnosis remains a challenge and coeliac disease is heavily underdiagnosed. The diagnosis of coeliac disease is achieved by combining coeliac disease serology and small intestinal mucosal histology during a gluten-containing diet. Currently, the only effective treatment for coeliac disease is a lifelong strict gluten-free diet; however, the diet is restrictive and gluten is difficult to avoid. Optimizing diagnosis and care in coeliac disease requires continuous research and education of both patients and health-care professionals.

Long-term follow-up in adults with coeliac disease: Predictors and effect on health outcomes

INTRODUCTION

Guidelines recommend regular follow-up in coeliac disease, but effect of this on long-term outcomes remains unclear.

AIMS

To evaluate predictors and significance of long-term follow-up.

METHODS

677 previously diagnosed coeliac patients were recruited for a nationwide health survey. Medical data were gathered through interviews and patient records. Current symptoms and quality of life were assessed by validated questionnaires and blood samples were drawn for serology. All variables were compared between patients with and without long-term (>2 years) follow-up.

RESULTS

15% had long-term follow-up, median duration 10 years. Predictors (p < 0.05) for the follow-up were immunological (35% vs. 24%) and circulatory (20% vs. 12%) comorbidities, whereas it was less common in subjects with musculoskeletal (23% vs. 34%) comorbidity and those not belonging to any at-risk group (16% vs. 27%). Patients with or without follow-up had comparable age, adherence and ability to manage a gluten-free diet and frequency of seropositivity. Also questionnaire scores paralleled, but those without follow-up reported more overall symptoms (16% vs. 26%). Most patients wished for follow-up.

CONCLUSION

Only a minority of patients had regular follow-up. However, patients with and without the follow-up were comparable in most long-term outcomes, indicating that it might not be always necessary. The results call for more personalized follow-up policies in coeliac disease.

Celiac Disease: Against the Grain in Gastroenterology

The incidence of celiac disease has risen quickly and has a worldwide distribution in Europe, North and South America, Asia, the Middle East and Africa. This is attributed in part to increased availability in screening but also to the fast-rising gluten consumption and perhaps unknown environmental factors. In daily practice, this means that more subclinical cases and very young and elderly patients are diagnosed. The pathogenesis of celiac disease is a T-cell driven process initiated by gluten, leading to increased intestinal permeability and villous atrophy. The process requires HLA genotypes DQ2, DQ8 or both. Additional non-HLA alleles have been identified in genome-wide association studies. Serological testing, followed by duodenal biopsies, are still required to confirm the diagnosis. Advances are in the making for novel biomarkers to monitor disease and for pharmacological support of celiac disease. Medical costs and patient-perceived disease burden remain high in celiac disease, which point to the need for ongoing research in drug development to improve quality of daily life. Drugs undergoing phase I and phase II clinical trials include intraluminal therapies and vaccines to restore immune tolerance. These therapies aim to reduce symptoms and mucosal injuries as adjunct therapies to a gluten-free diet.

Occurrence of serum antibodies against wheat alpha-amylase inhibitor 0.19 in celiac disease

The alcohol-soluble fraction of wheat gluten (gliadins) induces in genetically susceptible individuals immunologically mediated celiac disease (CLD). However, gliadins and related cereal proteins are not unique foodstuff targets of CLD patients´ immune system. Non-gluten wheat alpha-amylase inhibitor 0.19 (AAI 0.19) has been found to be capable of activating human monocyte-derived dendritic cells and inducing pro-inflammatory status in intestinal mucosa of patients with celiac disease (CLD). The possible contribution of this reactivity in incomplete remission of CLD patients on a gluten-free diet (GFD) is matter of contention. In an attempt to characterize the antigenicity of AAI 0.19 in patients with active CLD, patients on a GFD and healthy controls we developed ELISA employing wheat recombinant AAI 0.19. Using this test we revealed a significant (P<0.001) elevation of IgA anti-AAI 0.19 antibodies (Ab) in patients with active CLD (12 out of 30 patients were seropositive) but also in CLD patients on a GFD (15/46), in contrast to healthy controls (2/59). Anti-AAI 0.19 IgG Ab levels were increased (P<0.001) only in patients with active CLD (14/30) in contrast to the controls. Interestingly, the levels of anti-AAI 0.19 IgG Ab were decreased in CLD patients on a GFD (P<0.001, 1/46) compared to the controls (1/59). Notably, 20 out of 30 patients with active CLD were positive either for IgA or for IgG anti-AAI 0.19 Ab. Thus, the majority of CLD patients developed a robust IgA and IgG Ab response against AAI 0.19. These findings may contribute to the broadening of the knowledge about CLD pathogenesis.

Persistent mucosal damage and risk of epilepsy in people with celiac disease

BACKGROUND AND PURPOSE

Celiac disease (CD) is associated with an increased risk of developing epilepsy, a risk that persists after CD diagnosis. A significant proportion of patients with CD have persistent villous atrophy (VA) on follow-up biopsy. The objective of this study was to determine whether persistent VA on follow-up biopsy affected long-term epilepsy risk and epilepsy-related hospital emergency admissions.

METHODS

This was a nationwide cohort study. We identified all people in Sweden with histological evidence of CD who underwent a follow-up small intestinal biopsy (1969-2008). We compared those with persistent VA with those who showed histological improvement, assessing the development of epilepsy and related emergency hospital admissions (defined according to relevant International Classification of Diseases codes in the Swedish Patient Register). Cox regression analysis was used to assess outcome measures.

RESULTS

Villous atrophy was present in 43% of 7590 people with CD who had a follow-up biopsy. The presence of persistent VA was significantly associated with a reduced risk of developing newly-diagnosed epilepsy (hazard ratio, 0.61; 95% confidence interval, 0.38-0.98). On stratified analysis, this effect was primarily amongst males (hazard ratio, 0.35; 95% confidence interval, 0.15-0.80). Among the 58 patients with CD with a prior diagnosis of epilepsy, those with persistent VA were less likely to visit an emergency department with epilepsy (hazard ratio, 0.37; 95% confidence interval, 0.09-1.09).

CONCLUSIONS

In a population-based study of individuals with CD, persisting VA on follow-up biopsy was associated with reduced future risk of developing epilepsy but did not influence emergency epilepsy-related hospital admissions. The mechanism as to why persistent VA confers this benefit requires further exploration.