Tissue Transglutaminase Antibody Test Research Articles

Uncharted territory in linking population-based laboratory data for the epidemiology of celiac disease in Canada

IntroductionWe previously investigated the frequency of screening for celiac disease (CD) based on tissue transglutaminase antibody testing (tTG-IgA) and developed the first incident cohort of celiac autoimmunity in Canada. MethodsAdministrative data sources used in this study were population-based and covered the entire province of Alberta (~4.3M residents during study period). Various approaches to querying data were employed within a diverse team of health information managers, data analysts, clinical scientists, and gastroenterologists. This process involved a broad search for CD screening tests, thorough data inspection/cleaning, and numerous discussions to determine potential explanations for the findings. ResultsApproximately ~950,000 records for tTG-IgA were first identified. Records were then excluded due to missing/invalid patient identifiers or test results (0.8%), non-Alberta residency (0.4%), and duplicate records (1.1%). A final dataset included ~920,000 tTG-IgA tests on ~680,000 unique patients, which was also validated through a separate query performed by an analyst external to the study team. A conservative approach to excluding as many potential prevalent cases of CD was applied given a robust algorithm for CD has not yet been established in Canada. The final rate of celiac autoimmunity (34 per 100,000) offered further face validity based on prior estimates of diagnosed CD in Alberta and other countries reporting on celiac autoimmunity. ConclusionWhen developing a novel case definition or investigating unfamiliar outcomes using routinely collected data, collaboration across several disciplines is highly recommended. Certain stages of the project may require additional scrutiny and discussion to ensure findings are valid and reliable.

Path Towards Biopsy-Free Diagnosis of Celiac Disease in Pediatric Patients

BackgroundLaboratory testing for celiac disease in pediatric patients integrates serology, genetic susceptibility and duodenal biopsy examination. The 2023 American College of Gastroenterology guidelines recommend a biopsy-free approach in pediatric patients utilizing tissue transglutaminase antibody titers >10 times upper limit of normal and subsequent endomysial antibody seropositivity as sufficient for diagnosis. The objective of this study is to assess the diagnostic accuracy of biopsy-free approach at our pediatric hospital. MethodsWe conducted a retrospective study involving pediatric patients who underwent biopsy for diagnostic confirmation of celiac disease between May 2019 and May 2023. For these patients, the tissue transglutaminase and endomysial antibody test results were retrieved and performance of biopsy-free approach was assessed using the duodenal histology as the gold standard for celiac disease diagnosis. ResultsTissue transglutaminase antibody titers >10 times upper limit of normal alone demonstrated a positive predictive value of 99% for identifying celiac disease in children. Although endomysial antibody testing is underutilized at our center, its inclusion further improved the predictability to 100 %. ConclusionPositive predictive value of tissue transglutaminase antibody titers >10 times upper limit of normal is sufficiently high for celiac disease diagnosis in children and may allow for deferral of duodenal biopsy at diagnosis.

A174 TESTING FOR AND INCIDENCE OF CELIAC DISEASE AUTOIMMUNITY SAW SIGNIFICANT BUT TEMPORARY DECLINES DURING COVID-19 PANDEMIC

Abstract Background Celiac disease (CD) is an autoimmune disorder with various complications and long-term health risks. The COVID-19 pandemic affected the entire healthcare system—including screening for and diagnosing non-infectious conditions. Aims Determine how the COVID-19 pandemic affected the testing for, and incidence of, CD autoimmunity. Methods Using the population-based Alberta Medical Laboratory database, all tissue transglutaminase antibody tests (tTG-IgA) were identified in Alberta (April 2012 to March 2023). Incident cases of CD autoimmunity comprised of individuals newly positive for tTG-IgA between April 2015 and March 2023. Prevalent cases of CD were excluded based on previous tTG-IgA positivity and/or CD diagnosis codes in outpatient or inpatient settings. Average monthly percent changes and inflection points for testing and incidence rates were estimated using Joinpoint regression. Autoregressive integrated moving average models were performed to forecast rates if the pandemic had not occurred. Incidence rate ratios (IRRs) were estimated to compare a pre-pandemic era (April 2017 to March 2020) and a pandemic era (April 2020 to March 2023) overall and across subgroups. Results In the pandemic era, 311,971 tTG-IgA tests were performed on 284,882 unique individuals (21.1 per 1000 person-years (Table 1)). Testing decreased by 23.4% per month from February 2020 until May 2020 (Figure 1A). From June 2020 to August 2020, testing rates increased by 22.3% per month and then remained stable until the end of the study period. There were 4907 new cases of CD autoimmunity in the pandemic era, with an incidence of 36.3 per 100,000 person-years (Table 1). Incidence rates decreased by 14.1% per month from January 2020 until April 2020 (Figure 1B). Subsequently, incidence continued to rise by 2.0% per month from May 2020 until the end of the study period. Conclusions The COVID-19 pandemic appears to have had a minor impact on identifying potential CD. Future surveillance is needed to determine if the pandemic affected the diagnostic pathway to biopsy-confirmed CD through upper endoscopy procedures and any adverse outcomes individuals may have had from delayed diagnosis. Table 1: Testing and incidence rates for CD autoimmunity in Alberta in pre-pandemic era (April 2017 to March 2020) and pandemic era (April 2020 to March 2023) IRR=incidence rate ratio; CI=confidence interval Figure 1: Testing (A) and incidence (B) rates for CD autoimmunity before and after the start of the COVID-19 pandemic Funding Agencies CAG, CIHRhttps://triangleprogram.org

The risk for celiac disease after Covid-19 infection

BackgroundCeliac disease (CD) is an autoimmune disease leading to gastrointestinal symptoms and mineral deficiencies. The pathogenetic mechanisms, besides the clear HLA association, are elusive. Among environmental factors infections have been proposed. Covid-19 infection results in a systemic inflammatory response that often also involves the gastrointestinal tract. The aim of the present study was to investigate whether Covid-19 infection could increase the risk for CD.Patients and methodsAll patients, both children and adults, in the county Skåne (1.4 million citizens) in southern Sweden with newly diagnosed biopsy- or serology-verified CD or a positive tissue transglutaminase antibody test (tTG-ab) during 2016–2021 were identified from registries at the Departments of Pathology and Immunology, respectively. Patients with a positive Covid-19 PCR or antigen test in 2020 and 2021 were identified from the Public Health Agency of Sweden.ResultsDuring the Covid-19 pandemic (March 2020 – December 2021), there were 201 050 cases of Covid-19 and 568 patients with biopsy- or serology-verified CD or a first-time positive tTG-ab tests, of which 35 patients had been infected with Covid-19 before CD. The incidence of verified CD and tTG-ab positivity was lower in comparison to before the pandemic (May 2018 – February 2020; 22.5 vs. 25.5 cases per 100 000 person-years, respectively, incidence rate difference (IRD) -3.0, 95% CI -5.7 – -0.3, p = 0.028). The incidence of verified CD and tTG-ab positivity in patients with and without prior Covid-19 infection was 21.1 and 22.4 cases per 100 000 person-years, respectively (IRD − 1.3, 95% CI -8.5–5.9, p = 0.75).ConclusionsOur results indicate that Covid-19 is not a risk factor for CD development. While gastrointestinal infections seem to be an important part of the CD pathogenesis, respiratory infections probably are of less relevance.

Utility of narrow band imaging in predicting histology in celiac disease.

Narrow band imaging (NBI) with magnification better visualizes the duodenal microsurface and mucosal vascularity. NBI delineates villous atrophy better than conventional white light endoscopy. This study was conducted to evaluate the diagnostic accuracy of narrow band imaging with magnification(NBI-ME) in celiac disease(CD). In this prospective study, consecutive patients of suspected CD and controls were subjected to tissue transglutaminase antibody test and endoscopic evaluation initially with white light followed by NBI-ME, and biopsies were taken from duodenum. Duodenal villous patterns on NBIwere interpreted as normal, blunted distorted, and absent. Severity of villous atrophy was reported according to the modified Marsh criteria. One hundred andtwenty-two patients (mean age of 27.53 ± 13.37years and a male to female ratio of 1:1.26) and 40 controls were studied. The sensitivity and specificity of NBI-ME in predicting villous atrophy were found to be 95.54% and 90%, respectively. The specificity and negative predictive value of NBI-ME in predicting villous atrophy amongst controls was 100% and 97.5%, respectively. Abnormal findings (blunted and absent villous patterns) combined with elevated transglutaminase antibody (> 5-fold) were found to have high accuracy in predicting villous atrophy. NBI with magnification has high sensitivity and specificity in predicting villous atrophy in patients with celiac disease.

Correlation of TTG IgA Level with Small Intestinal Histopathological Changes for Celiac Disease among Adult Saudi Patients.

Background and objectivesAccording to recent guidelines, a diagnosis of celiac disease (CD) can be made without a biopsy, especially in children. There are no enough studies despite high prevalence and differences in genetic, race, and cultures. Therefore, we examined the correlation between tissue transglutaminase (TTG) and duodenal biopsy changes in our region because we are identical and different from others in culture, environment, and habits, and the correlation is same as that in different regions.MethodsA retrospective cohort study at the Ministry of National Guard Health Affaires (NGHA) health care facilities that are distributed throughout kingdom of Saudi Arabia from April 19, 2015, till March 29, 2018. This study used the BESTCARE system that includes data from all NGHA facilities; data from 513 patients with CD were collected. All patients diagnosed with celiac disease aged 15 years or more, confirmed by improvement on gluten-free diet (GFD), and were not on GFD before endoscopy or serology test or both of them were included in the study, and the TTG IgA level was measured at the same time or within 2–3 months of biopsy date. The exclusion criteria were negative duodenal biopsy, which is less than 2; patients with negative biopsy and negative serology; patients who were on GFD before testing, and any patients known to have immunity diseases or illness causing mucosal changes. The TTG IgA level was measured in IU/ mL and was labeled as negative (<20 IU/mL) and positive (≥ 20 IU/mL) based on the cutoff value. However, Intestinal biopsy findings were identified as Marsh classification groups.ResultsOne hundred thirty-four patients who met the inclusion criteria were included in the study. Median age of our sample was 24 years (16–37 years). Among these, 99 (73.88%) were female patients, whereas male patients were only 35 (26.12%). Histopathologic investigation of intestinal biopsy were Marsh 0 group was 16 cases (11.9%), Marsh 1 group was 8 cases (6%), Marsh 2 group was 4 cases (3%), Marsh 3a group was 32 cases (23.9%), Marsh 3b group was 64 cases (47.8%), and Marsh 3c group was 10 cases (7.5%). The TTG IgA antibody serology groups were <20 IU/mL in 13 cases (9.7%) and ≥20 IU/mL in 121 cases (90.3%). Among all patients with CD who had negative biopsy (Marsh 0 group), 16 (100%) of them had positive TTG IgA antibody. However, among patients with Marsh 1 group biopsy, 5 (62.5%) cases had negative TTG IgA antibody compared with 3 (37.5%) positive cases. Of the four cases (100%) with Marsh 2 group, all of them had positive TTG IgA antibody. However, in Marsh 3a group biopsy, 3 (9.4%) cases had negative TTG IgA antibody compared with 29 (90.6%) cases with positive TTG IgA antibody. Furthermore, among the patients with Marsh 3b group biopsy, 5 (7.8%) had negative antibody and 59 (92.2%) had positive serology. Of all biopsies of Marsh 3c group, 10 (100 %) had positive TTG IgA antibody.ConclusionsIn perspective of high prevalence of CD in KSA, even more than western countries, we can pretend that positive TTG antibody tests can be applied for the diagnosis of CD without biopsy, particularly in symptomatic patients along with high titer, that is, 5–10 times the upper limit of normal (ULN). However, to validate it further, we need larger prospective studies in which duodenal biopsies should be taken according to recommended protocol and should be interpreted by experienced pathologist. Furthermore, biopsy is still needed in patients who do not show clinical improvement on a gluten-free diet and in cases with mildly or moderately elevated TTG IgA.

Comparison of Tissue Transglutaminase and Anti-Endomysial Antibody Tests in Diagnosis of Celiac Disease

Background: Although initially considered as a digestive tract disease, celiac disease (CD) can cause problems and complications in most other organs. Common serologic tests for the diagnosis of CD include anti-tissue transglutaminase (tTG) and anti-endomysial Ab (EMA). A more recent test includes anti-deamidated gliadin peptide. Objectives: This study aimed to compare the values of tissue transglutaminase and endomysial antibodies in A and G Immunoglobin subtypes in patients with a definitive diagnosis of CD. Methods: Patients suspected of CD referring to a Gastrointestinal Pediatric Clinic were evaluated for CD using IgG and IgA for tissue transglutaminase and endomysial antibodies and total IgA. Endoscopy and biopsy were done based on the CD diagnosis protocol. The demographic data of children were recorded in a questionnaire and then analyzed. Results: Of the 54 patients diagnosed with CD, 29 were females and 25 were males. TTG-IgA had the highest positivity rate. Tests based on IgA were more positive than IgG tests. More than one test was positive in 81.5 of the patients. All four tests were positive in 16 patients. In 18.5 percent of patients, just one test was positive. In the latter group, TTG-IgA was positive in four patients. The coefficient of agreement between EMA-IgA and TTG-IgA was 0.435, which was statistically significant. Conclusions: We suggest tissue transglutaminase and endomysial antibodies in A and G Immunoglobin subtypes for the diagnosis of CD. In this method, the diagnostic sensitivity of CD is high and in the next step, endoscopy and sampling can increase the specificity value. If the tests are not available, preferable tests are IgA subtype antibodies. © 2019, Journal of Comprehensive Pediatrics. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/) which permits copy and redistribute the material just in noncommercial usages, provided the original work is properly cited.

Prevalence and clinical profile of celiac disease in children with type 1 diabetes mellitus.

Objective:To determine the prevalence of celiac disease (CD) in children with type 1 diabetes mellitus (TIDM) in follow-up in a Tertiary Care Referral Centre in Western India and to describe the clinical features indicative of CD in screened patients of TIDM.Study Design:In this single center observational cross-sectional study, 71 children who were diagnosed with TIDM were subjected to screening for CD with tissue transglutaminase antibody testing. Those who tested positive were offered intestinal biopsy for the confirmation of diagnosis. Clinical profiles of both groups of patients were compared and manifestations of CD were delineated.Results:The study revealed the prevalence of CD (based on serology) in children with Type 1 diabetes as 15.49%. The prevalence of biopsy-confirmed CD was 7.04%. Of the diagnosed CD patients, one-third were symptomatic at the time of screening while the majority was asymptomatic. The major clinical features indicative of CD were intestinal symptoms, anemia, rickets, and short stature. Autoimmune thyroid disease was prevalent in 29.6% of the patients with TIDM followed by CD.Conclusions:The high prevalence of CD in children with Type 1 diabetes emphasizes the need for routine screening programs to be in place for these high-risk populations. The clinical profile of patients with CD further elaborates the indicators of CD and the need to screen for them.

Re: "Decreased Risk of CEliac Disease in Patients With Helicobacter Pylori Colonization"

Although their fascinating work supports this model, there may be other models to consider. It is not clear whether patientshave CD from birth, but we do knowthat the mostcommon age for presentation is during the fourth or fifth decade of life (4). Could infection play another role? Our group conducted a 2-part study that may provide evidence to support the “second hit” hypothesis. This hypothesis postulates that, in addition to a genetic predisposition, an environmental trigger is required to initiate the autoimmune process (5). In the first part of the study, we investigated 101 patients (48 men; median age, 57 years) with stool culture– proven bacterial gastroenteritis (95% Campylobacter species) for CD. All patients underwent tissue transglutaminase and endomysial antibody testing, and if either test was positive, we performed a small-bowel biopsy. The prevalence of CD was higher in this group of patients than in a healthy control group (2.97% vs. 1%, P = 0.10). In the second part of our study, we used a validated questionnaire (6) to assess patients with CD or inflammatory bowel disease, as well as healthy controls. A total of 69 of 233 (29.6%) patients with CD and 53 of 196 (27.1%) patients with inflammatory bowel disease self-reported having a gastrointestinal infection within the 12 months prior to diagnosis. In both diseases, this rate was significantly greater than in healthy controls (15 of 219 (6.8%) patients) (P < 0.0001). The role of infection in the development of CD and other autoimmune conditions is complex (3). Circumstantial evidence exists for both the protective and deleterious consequences of gastrointestinal infection, and further work is required to delineate more clearly the role of different pathogens in the development of CD. ACKNOWLEDGMENTS

Letter: biochemical response to combination anti‐retroviral therapy in patients with primary biliary cirrhosis

1. Valitutti F, De Vitis I, Cucchiara S. Letter: follow-up practices in coeliac disease – intestinal biopsy after child-to-adult transition might be useful. Aliment Pharmacol Ther 2014; 39: 234–5. 2. Sharkey LM, Corbett G, Currie E, Lee J, Sweeney N, Woodward JM. Optimising delivery of care in Coeliac Disease – comparison of the benefits of repeat biopsy and serological follow up. Aliment Pharmacol Ther 2013; 38: 1278–91. 3. National Institute for Health and Clinical Excellence. Coeliac Disease: Recognition and Assessment of Coeliac Disease. London: National Institute for Health and Clinical Excellence, 2009. Available at: http://www.nice.org.uk/CG86. 4. Lewis NR, Scott BB. Systematic review: the use of serology to exclude or diagnose coeliac disease (a comparison of the endomysial and tissue transglutaminase antibody tests). Aliment Pharmacol Ther 2006; 24: 47–54. 5. Corazza GR, Villanacci V. Coeliac disease. J Clin Pathol 2005; 58: 573–4.

Letter: follow‐up practices in coeliac disease – intestinal biopsy after child‐to‐adult transition might be useful; authors' reply

We are grateful to Dr Valitutti and colleagues for their insightful comments arising from our recent publication.1, 2 We are particularly glad that they highlighted the 15% of our patients who were seronegative for tissue transglutaminase (TTG) antibodies. Studies frequently cited as demonstrating the performance of the TTG antibody test are often methodologically poor and open to bias that artificially inflates the sensitivity. This is inevitable, given the existence of asymptomatic coeliac disease and the difficulties inherent in performing duodenal biopsies on unselected individuals. Our seronegativity rate is in keeping with existing systematic reviews, such as that from the National Institute for Health and Clinical Excellence,3 and we hope that our paper encourages critical re-appraisal of the sensitivity of the TTG antibody test in diagnosis – and follow-up – of coeliac disease. Existing reviews – including that cited by our colleagues4 – demonstrate a lower sensitivity for endomysial antibodies (EMA) than TTG. In our unpublished audit of 1364 consecutive samples, no patient tested negative for TTG and positive for EMA. Indeed, the higher specificity of EMA has led to its recommendation for confirming a positive TTG test.3 Whilst our seronegative patients are carefully scrutinised for alternative diagnoses, a further benefit of our re-biopsy strategy is the possibility of cross-referencing not only symptomatic relief following gluten withdrawal in these patients but also histological recovery to help confirm the diagnosis. Where the diagnosis remains questionable, we check HLA and/or carry out a gluten re-challenge. We agree that the Marsh 2 category is difficult5 and we generally apply the Corazza definitions both clinically and in this study. We intend that discharge outcomes in our cohort will be the subject of a separate study. Finally, we agree entirely that adolescents transitioning into adult care may benefit from a re-appraisal including a follow-up biopsy and it is routine to offer this in our practice. The authors' declarations of personal and financial interests are unchanged from those in the original article.2

PTU-181 The Low Diagnostic Yield of Non-Targeted Duodenal Biopsies

IntroductionDuodenal mucosa of normal endoscopic appearance is often biopsied (non-targeted biopsy) to exclude coeliac disease (CD) as the cause of iron deficiency anaemia or other symptoms. Our aim was to...

PTH-192 Once Negative always Negative? – the Clinical Utility of Repeating TTG

IntroductionPatients with chronic or recurrent abdominal symptoms, or anaemia, often undergo repeated rounds of investigations including tissue transglutaminase (TTG) antibody testing. The aim of this study was to investigate a)...

PTU-185 What is the Cost of Duodenal Biopsies in Patients without Serological Evidence of Coeliac Disease?

IntroductionThe BSG guidelines recommend anti tissue transglutaminase antibody (TTG) testing as a first line test for coeliac disease. Duodenal biopsies (D2) should be performed only after a positive serological test...

Quality not quantity for transglutaminase antibody 2: the performance of an endomysial and tissue transglutaminase test in screening coeliac disease remains stable over time

National Institute of Clinical Excellence (NICE) and European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidance for the diagnosis of coeliac disease has been published. However, there is some controversy regarding the advice on the use of stratifying levels of immunoglobulin (IgA) tissue transglutaminase antibody (TG2) test positivity in the absence of test standardization and the vagueness of the indication to test equivocal samples. Using repeat service audit, we demonstrate that a combination of TG2 followed by IgA endomysial antibodies (EMA) is the best strategy for all degrees of mucosal abnormality using our test combination. Reliance upon immunoassay titre is not as effective, and cannot be applied consistently across populations in the absence of assay standardization. Guidelines advocating the use of tests should involve experts in laboratory diagnostics and external quality assurance to ensure that errors of generalization do not occur and that test performance is achievable in routine diagnostic use.

Does capsule endoscopy have a role in equivocal coeliac disease?

IntroductionEndomysial antibody (EMA) and tissue transglutaminase (tTG) antibody testing is used to investigate for coeliac disease. Demonstration of villous atrophy (VA) on small bowel biopsy in the presence of positive...

Value of IgA human recombinant tissue transglutaminase antibody test in diagnosis of symptomatic celiac disease in children

Objective: To identify the value of serological examination in diagnosis of celiac disease in children. Patients and methods: A prospective case series study was conducted at private clinics in Mosul city during the period from 30th of October 2007 to 30 th of October 2009. A total of 40 patients (29 males, 11 females) aged more than 6 months on gluten containing diet presented with symptoms suggestive of celiac disease were screened by serological testing using second generation ELISAs IgA human recombinant tissue transglutaminase antibody. Multiple duodenal biopsies were performed for every patient enrolled in this study regardless of the results of serology. Statistical methods were used to indicate sensitivity, specificity, negative and positive predictive values of serological test in comparison to biopsy results. Results: A total of 16 (40%) out of 40 symptomatic patients with mean age of 51 months, demonstrated both positive IgA anti-tissue transglutaminase antibody test and biopsy results for celiac disease, the remaining 24 patients (60%) displayed negative results for both serology and biopsy. IgA anti-tissue transglutaminase antibody test had (100%) specificity, sensitivity, positive predictive value, and negative predictive value in relation to biopsy results. Conclusion: Our results provide additional support to the concept that IgA anti-tissue transglutaminase antibodies can be used as a diagnostic serologic marker for celiac disease.

The prevalence of celiac disease in Europe: Results of a centralized, international mass screening project

Introduction. Although the prevalence of celiac disease (CD) has been extensively investigated in recent years, an accurate estimate of CD frequency in the European population is still lacking. The aims of this study were: 1) to establish accurately the prevalence of CD in a large sample of the European population (Finland, Germany, Italy, and UK), including both children and adults; and 2) to investigate whether the prevalence of CD significantly varies between different areas of the European continent.Materials and methods. Samples were drawn from the four populations. All 29,212 participants were tested for CD by tissue transglutaminase (tTG) antibody test. Positive and border-line findings were further tested for serum endomysial antibodies (EMA). All serological determinations were centrally performed. Small-bowel biopsies were recommended to autoantibody-positive individuals. Previously diagnosed cases were identified.Results. The overall CD prevalence (previously diagnosed plus anti-tTG and EMA positives) was 1.0% (95% CI 0.9–1.1). In subjects aged 30–64 years CD prevalence was 2.4% in Finland (2.0–2.8), 0.3% in Germany (0.1–0.4), and 0.7% in Italy (0.4–1.0). Sixty-eight percent of antibody-positive individuals showed small-bowel mucosal changes typical for CD (Marsh II/III lesion).Conclusions. CD is common in Europe. CD prevalence shows large unexplained differences in adult age across different European countries.

714 Celiac Disease in Type 1 Diabetes Children From Constanta County, Romania

Introduction: Type 1 diabetes and celiac disease are both immunologic disorders where specific HLA alleles are associated with disease risk. Objective: To estimate the prevalence of celiac disease (CD) and to describe the clinical features and HLA class II genotypes predictive of CD in our pediatric type 1 diabetes mellitus patients. Material and Methods: 65 patients underwent serologic screening with endomysial antibody and tissue transglutaminase antibody testing. CD was confirmed in serologic positive patients by intestinal biopsy. All the patients also underwent HLA class II genotyping. Determination of HLA-DQ alleles was done by sequence-specific oligonucleotids hybridization after DNA amplification by polymerase chain reaction. Results: A total of 65 patients with type 1 diabetes were tested, representing 12 % of all type 1 diabetes patients from our county, and 4 had biopsy-proven CD, representing 6.1%, for an estimated point prevalence of 7.0% (95% Confidence Interval, 3.5%-12.1%). Most CD-positive type 1 diabetes patients were asymptomatic and expressed an atrisk CD haplotype with at least one of but not both HLA DQ2 or DQ8. Patient 1: DRB1 3,3 (0301,0301)/ DQB1 2,2 (0201,0201). Patient 2: DRB1 4,13 (0401, 1302)/ DQB1 3,6 (0302, 0604). Patient 3: DRB1 3,16 (0301, 1601)/ DQB1 2, 5 (0201, 0502). Patient 4: DRB1 3,3 (0301, 0301)/ DQB1 2,2 (0201, 0201). Conclusions: Celiac disease is not rare in our patients with type 1 diabetes, and most CD-positive patients with type 1 are asymptomatic irrespective of age at screening. HLA-DQ genotype in children with T1DM may help in estimating the CD risk.

The Role of Capsule Endoscopy in Suspected Celiac Disease Patients with Positive Celiac Serology

Endomysial antibody (EMA) and tissue transglutaminase (tTG) antibody testing is used to screen subjects with suspected celiac disease. However, the traditional gold standard for the diagnosis of celiac disease is histopathology of the small bowel. As villous atrophy may be patchy, duodenal biopsies could potentially miss the abnormalities. Capsule endoscopy can obtain images of the whole small intestine and may be useful in the early diagnosis of celiac disease. To evaluate suspected celiac disease patients who have positive celiac serology and normal duodenal histology and to determine, with capsule endoscopy, whether these patients have any endoscopic markers of celiac disease. Twenty-two subjects with positive celiac serology (EMA or tTG) were prospectively evaluated. Eight of the subjects had normal duodenal histology and 14 had duodenal histology consistent with celiac disease. All subjects underwent capsule endoscopy. Endoscopic markers of villous atrophy such as loss of mucosal folds, scalloping, mosaic pattern, and visible vessels were assessed. Eight subjects with normal duodenal histology had normal capsule endoscopy findings. In the 14 subjects with duodenal histology that was consistent with celiac disease, 13 had celiac disease changes seen at capsule endoscopy. One subject with normal capsule endoscopy findings showed Marsh IIIc on duodenal histology. Using duodenal histology as the gold standard, capsule endoscopy had a sensitivity of 93%, specificity of 100%, PPV of 100%, and NPV of 89% in recognizing villous atrophy. Capsule endoscopy is useful in the detection of villous abnormalities in untreated celiac disease. Patients with positive celiac serology (EMA or tTG) and normal duodenal histology are unlikely to have capsule endoscopy markers of villous atrophy.