Can tissue transglutaminase antibody titers replace small-bowel biopsy to diagnose celiac disease in select pediatric populations?

Serum anti-tissue transglutaminase IgA and prediction of duodenal villous atrophy in adults with suspected coeliac disease without IgA deficiency (Bi.A.CeD): a multicentre, prospective cohort study

BACKGROUND

Whether coeliac disease in adults can be diagnosed with serology alone remains controversial. We aimed to evaluate the accuracy of serum anti-tissue transglutaminase IgA (tTG-IgA) in the diagnosis of coeliac disease.

METHODS

In this multicentre, prospective cohort study, adult participants (aged ≥18 years) with suspected coeliac disease without IgA deficiency who were not on a gluten-free diet and who had a local serum tTG-IgA measurement, were enrolled from Feb 27, 2018, to Dec 24, 2020, by 14 tertiary referral centres (ten from Europe, two from Asia, one from Oceania, and one from South America) to undergo local endoscopic duodenal biopsy. Local serum tTG-IgA was measured with 14 different test brands and concentration expressed as a multiple of each test's upper limit of normal (ULN), and defined as positive when greater than 1 times the ULN. The main study outcome was the reliability of serum tests for the diagnosis of coeliac disease, as defined by duodenal villous atrophy (Marsh type 3 or Corazza-Villanacci grade B). Histology was evaluated by the local pathologist, with discordant cases (positive tTG-IgA without duodenal villous atrophy or negative tTG-IgA with duodenal villous atrophy) re-evaluated by a central pathologist. The reliability of serum tests for the prediction of duodenal villous atrophy was evaluated according to sensitivity, specificity, positive predictive value, negative predictive value, and the area under the receiver operating characteristic curve (AUC) for categorical and continuous data.

FINDINGS

We enrolled 436 participants with complete local data on serum tTG-IgA and duodenal histology (296 [68%] women and 140 [32%] men; mean age 40 years [SD 15]). Positive serum tTG-IgA was detected in 363 (83%) participants and negative serum tTG-IgA in 73 (17%). Of the 363 participants with positive serum tTG-IgA, 341 had positive histology (true positives) and 22 had negative histology (false positives) after local review. Of the 73 participants with negative serum tTG-IgA, seven had positive histology (false negatives) and 66 had negative histology (true negatives) after local review. The positive predictive value was 93·9% (95% CI 89·2-98·6), the negative predictive value was 90·4% (85·5-95·3), sensitivity was 98·0% (95·3-100·0), and specificity was 75·0% (66·6-83·4). After central re-evaluation of duodenal histology in 29 discordant cases, there were 348 true positive cases, 15 false positive cases, 66 true negative cases, and seven false negative cases, resulting in a positive predictive value of 95·9% (92·0-99·8), a negative predictive value of 90·4% (85·5-95·3), a sensitivity of 98·0% (95·3-100·0), and a specificity of 81·5% (73·9-89·1). Either using the local or central definition of duodenal histology, the positive predictive value of local serum tTG-IgA increased when the serological threshold was defined at increasing multiples of the ULN (p<0·0001). The AUC for serum tTG-IgA for the prediction of duodenal villous atrophy was 0·87 (95% CI 0·81-0·92) when applying the categorical definition of serum tTG-IgA (positive [>1 × ULN] vs negative [≤1 × ULN]), and 0·93 (0·89-0·96) when applying the numerical definition of serum tTG-IgA (multiples of the ULN). Additional endoscopic findings included peptic gastritis (nine patients), autoimmune atrophic gastritis (three), reflux oesophagitis (31), gastric or duodenal ulcer (three), and Barrett's oesophagus (one). In the 1-year follow-up, a midgut ileum lymphoma was diagnosed in a woman on a gluten-free diet.

INTERPRETATION

Our data showed that biopsy could be reasonably avoided in the diagnosis of coeliac disease in adults with reliable suspicion of coeliac disease and high serum tTG-IgA.

FUNDING

None.

Correlation of Anti-Tissue Transglutaminase Antibodies With the Mucosal Changes and IgA Status of Children With Celiac Disease

OBJECTIVES

The objective of this study was to assess the association between serological markers and changes of the intestinal mucosa in children with celiac disease (CD).

METHODS

Clinical data from CD patients under 15 years old were collected from the participating centers in an on-line multicenter nationwide observational Spanish registry called REPAC-2 (2011-2017). Correlation between anti-tissue transglutaminase antibodies (t-TGA) levels and other variables, including mucosal damage and clinical findings (symptoms, age, and gender), was assessed.

RESULTS

A total of 2955 of 4838 patients had t-TGA and a small bowel biopsy (SBB) performed for CD diagnosis. A total of 1931 (66.2%) patients with normal IgA values had a Marsh 3b-c lesion and 1892 (64.9%) had t-TGA Immunoglobulin A (IgA) ≥ 10 times upper limit of normal (ULN). There is a statistically significant association between t-TGA IgA levels and the degree of mucosal damage ( P < 0.001), the higher the t-TGA IgA levels the more severe the mucosal damage. Those patients who reported symptoms had more severe mucosal damage ( P = 0.001). On the contrary, there was a negative association between age and changes of the intestinal mucosa ( P < 0.001). No association was found with gender. Regarding the IgA-deficient patients, 47.4% (18 cases) had t-TGA Immunoglobulin A (IgA) ≥ 10 times ULN and a Marsh 3b-c lesion was observed in 68.4% (26 patients). No statistical relation was found between t-TGA IgG levels and the changes of the intestinal mucosa, neither a relation with age, gender, or symptoms.

CONCLUSIONS

There is a positive correlation between t-TGA IgA levels and the severity of changes of the intestinal mucosa. Such correlation was not found in IgA-deficient patients who had positive t-TGA IgG serology. The results in this group of patients support the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition recommendations about the need of performing a SBB in IgA-deficient individuals despite high t-TGA IgG levels.

Defining the optimum strategy for identifying adults and children with coeliac disease: systematic review and economic modelling

BACKGROUND

Coeliac disease is an autoimmune disorder triggered by ingesting gluten. It affects approximately 1% of the UK population, but only one in three people is thought to have a diagnosis. Untreated coeliac disease may lead to malnutrition, anaemia, osteoporosis and lymphoma.

OBJECTIVES

The objectives were to define at-risk groups and determine the cost-effectiveness of active case-finding strategies in primary care.

DESIGN

(1) Systematic review of the accuracy of potential diagnostic indicators for coeliac disease. (2) Routine data analysis to develop prediction models for identification of people who may benefit from testing for coeliac disease. (3) Systematic review of the accuracy of diagnostic tests for coeliac disease. (4) Systematic review of the accuracy of genetic tests for coeliac disease (literature search conducted in April 2021). (5) Online survey to identify diagnostic thresholds for testing, starting treatment and referral for biopsy. (6) Economic modelling to identify the cost-effectiveness of different active case-finding strategies, informed by the findings from previous objectives.

DATA SOURCES

For the first systematic review, the following databases were searched from 1997 to April 2021: MEDLINE® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), Cochrane Library, Web of Science™ (Clarivate™, Philadelphia, PA, USA), the World Health Organization International Clinical Trials Registry Platform ( WHO ICTRP ) and the National Institutes of Health Clinical Trials database. For the second systematic review, the following databases were searched from January 1990 to August 2020: MEDLINE, Embase, Cochrane Library, Web of Science, Kleijnen Systematic Reviews ( KSR ) Evidence, WHO ICTRP and the National Institutes of Health Clinical Trials database. For prediction model development, Clinical Practice Research Datalink GOLD, Clinical Practice Research Datalink Aurum and a subcohort of the Avon Longitudinal Study of Parents and Children were used; for estimates for the economic models, Clinical Practice Research Datalink Aurum was used.

REVIEW METHODS

For review 1, cohort and case-control studies reporting on a diagnostic indicator in a population with and a population without coeliac disease were eligible. For review 2, diagnostic cohort studies including patients presenting with coeliac disease symptoms who were tested with serological tests for coeliac disease and underwent a duodenal biopsy as reference standard were eligible. In both reviews, risk of bias was assessed using the quality assessment of diagnostic accuracy studies 2 tool. Bivariate random-effects meta-analyses were fitted, in which binomial likelihoods for the numbers of true positives and true negatives were assumed.

RESULTS

People with dermatitis herpetiformis, a family history of coeliac disease, migraine, anaemia, type 1 diabetes, osteoporosis or chronic liver disease are 1.5-2 times more likely than the general population to have coeliac disease; individual gastrointestinal symptoms were not useful for identifying coeliac disease. For children, women and men, prediction models included 24, 24 and 21 indicators of coeliac disease, respectively. The models showed good discrimination between patients with and patients without coeliac disease, but performed less well when externally validated. Serological tests were found to have good diagnostic accuracy for coeliac disease. Immunoglobulin A tissue transglutaminase had the highest sensitivity and endomysial antibody the highest specificity. There was little improvement when tests were used in combination. Survey respondents (n = 472) wanted to be 66% certain of the diagnosis from a blood test before starting a gluten-free diet if symptomatic, and 90% certain if asymptomatic. Cost-effectiveness analyses found that, among adults, and using serological testing alone, immunoglobulin A tissue transglutaminase was most cost-effective at a 1% pre-test probability (equivalent to population screening). Strategies using immunoglobulin A endomysial antibody plus human leucocyte antigen or human leucocyte antigen plus immunoglobulin A tissue transglutaminase with any pre-test probability had similar cost-effectiveness results, which were also similar to the cost-effectiveness results of immunoglobulin A tissue transglutaminase at a 1% pre-test probability. The most practical alternative for implementation within the NHS is likely to be a combination of human leucocyte antigen and immunoglobulin A tissue transglutaminase testing among those with a pre-test probability above 1.5%. Among children, the most cost-effective strategy was a 10% pre-test probability with human leucocyte antigen plus immunoglobulin A tissue transglutaminase, but there was uncertainty around the most cost-effective pre-test probability. There was substantial uncertainty in economic model results, which means that there would be great value in conducting further research.

LIMITATIONS

The interpretation of meta-analyses was limited by the substantial heterogeneity between the included studies, and most included studies were judged to be at high risk of bias. The main limitations of the prediction models were that we were restricted to diagnostic indicators that were recorded by general practitioners and that, because coeliac disease is underdiagnosed, it is also under-reported in health-care data. The cost-effectiveness model is a simplification of coeliac disease and modelled an average cohort rather than individuals. Evidence was weak on the probability of routine coeliac disease diagnosis, the accuracy of serological and genetic tests and the utility of a gluten-free diet.

CONCLUSIONS

Population screening with immunoglobulin A tissue transglutaminase (1% pre-test probability) and of immunoglobulin A endomysial antibody followed by human leucocyte antigen testing or human leucocyte antigen testing followed by immunoglobulin A tissue transglutaminase with any pre-test probability appear to have similar cost-effectiveness results. As decisions to implement population screening cannot be made based on our economic analysis alone, and given the practical challenges of identifying patients with higher pre-test probabilities, we recommend that human leucocyte antigen combined with immunoglobulin A tissue transglutaminase testing should be considered for adults with at least a 1.5% pre-test probability of coeliac disease, equivalent to having at least one predictor. A more targeted strategy of 10% pre-test probability is recommended for children (e.g. children with anaemia).

FUTURE WORK

Future work should consider whether or not population-based screening for coeliac disease could meet the UK National Screening Committee criteria and whether or not it necessitates a long-term randomised controlled trial of screening strategies. Large prospective cohort studies in which all participants receive accurate tests for coeliac disease are needed.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42019115506 and CRD42020170766.

FUNDING

This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 44. See the NIHR Journals Library website for further project information.

Role of HLA-DQ typing and antitissue transglutaminase antibody titres in diagnosing coeliac disease among Sudanese children with type 1 diabetes mellitus

Objective

The aim of the study was to determine the prevalence of coeliac disease (CD) and to recognise Human leukocyte antigen (HLA)-associated hereditary susceptibility to Sudanese CD patients with type 1 diabetes mellitus (DM1).

Design

Antitissue transglutaminase IgA (anti-TG IgA) was measured in the serum of 373 children affected with DM1 aged 1–19-year old and in 100 serum samples from non-diabetic control children. Histological examination was performed in 19 children seropositive for anti-TG IgA (17 DMI and 2 controls). Additionally, PCR-based analysis of Major histocompatibility complex, class II, DQ beta 1 (HLA-DQB1) genotyping was implemented in three study population groups as follows: group 1 (n=25) (+ve DM1 and +ve CD), group 2 (n=63) (-ve DM1 and +ve CD) and control group 3 (n=2) (+ve CD).

Results

Twenty-six Sudanese children with DM1 out of 373 (6.97%) were seropositive for anti-TG IgA. Duodenal biopsy revealed Marsh 2 and 3 in 13 out of 17 (76.47%) seropositive anti-TG IgA patients with DM1. Significant association (p<0.05) was detected between the level of anti-TG IgA autoantibodies (IU/mL) and Marsh stage. HLA DQ2 and DQ8 were found in 88% (22/25) and 8% (2/25) of examined patients with CD with DM1, respectively.

Conclusions

Anti-TG IgA titre of greater than 10 times upper limit of normal (≥10× ULN) can be useful for detecting CD in children with type 1 diabetes without duodenal biopsy. HLA testing in children with DM1 appears to provide little added benefit given the high prevalence (96%) of HLA DQ2/DQ8 in children with DM1.

Association of Anti-tissue Transglutaminase Antibody Titers and Duodenal Biopsy Findings in Pediatric Patients of Celiac Disease

Aims & Objectives

To ascertain the association of serum anti-tissue transglutaminase (anti-tTG) antibody titers with the severity of duodenal mucosal damage on histology andto predict a possible cut-off value of anti-tTG antibody titers for the diagnosis of Celiac disease. Marsh grading greater than two in conjunction with clinical assessment, which may help avert an invasive endoscopic procedure, especially in medically unfit children.

Materials & Methods

A retrospective study was designed wherein demographic and laboratory data of children aged less than 12 years with raised anti-tTG antibody titers with available histopathology of duodenal biopsies were extracted from the hospital medical records and reviewed.

Results

A total of 134 children were included in the study, which showed female preponderance. Histopathological changes, characteristic of Celiac disease, were observed in 116 cases; seven among the rest showed evidence of Giardiasis, and 13 could be considered potential Celiac. Of the 116 patients, 1.7% belonged to Marsh grade I, 5.2% grade II and 8.6%, 26.7%, and 57.7% to grade IIIA, IIIB, and IIIC, respectively. A significant association was found between anti-tTG antibody titers and Marsh grading. The cut-off value of anti-tTG antibody titer levels for diagnosing Celiac disease using receiver operating characteristics (ROC) curve in predicting Marsh greater than two at histology was observed to be 84.6 U/ml with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 91.7%, 68.4%, 94.2%, and 59%, respectively.

Conclusion

An anti-tTG antibody titer greater than 10 times the upper limit of normal (≥84 U/ml) is significantly associated with Marsh grade greater than two. Standard stool microscopy may be used as a simple tool in the workup of all children with raised anti-tTG antibody levels to rule out Giardiasis to avert unnecessary endoscopic evaluation for Celiac disease in such cases.

Morphological evaluation of bulb and distal duodenal biopsies in pediatric celiac disease with clinical and serological correlation

Background and Aims

An early correct diagnosis of celiac disease (CD) is fundamental to reversal of symptoms and prevention of complications in pediatric patients. Our aim was to evaluate the role of duodenal bulb biopsy by studying the degree of mucosal damage in the duodenal bulb (D1) and second part of the duodenum (D2) and correlating the findings with serum IgA anti-tTG levels.

Settings and Design

Pediatric patients (age <18 years) with clinical suspicion of CD and positive IgA anti-tTG titers were consecutively enrolled over a period of one year. Demographic variables, anthropometry, clinical history, laboratory values and endoscopic findings were studied. Endoscopic biopsies obtained from D1 and D2 were evaluated and assigned histopathologic grades that were correlated with serology.

Statistical Analysis Used

Descriptive statistics were employed.

Results

A total of 37 clinically suspected cases of pediatric CD were studied. The mean age was 6.7 years and the M:F ratio was 1:1.3. Thirty-two (32) children had varying degrees of growth impairment. Eight (8) children had only extra-intestinal symptoms. Thirty (30) children were anemic, hypoalbuminemia was seen in five (5) children while transaminitis was seen in two (2) children. IgA anti-tTG >300 U/ml was associated with Marsh-Oberhuber Grade 3 morphology at atleast one site.

Conclusions

Low positive serology values should be confirmed by histopathology. Biopsies should be taken even in the absence of endoscopic abnormality. Additional D1 biopsies placed in a separate container can increase the diagnostic yield.

Value of biopsy in a cohort of children with high-titer celiac serologies: observation of dynamic policy differences between Europe and North America

Background

Healthcare systems implement change at different rates because of differences in incentives, organizational processes, key influencers, and management styles. A comparable set of forces may play out at the national and international levels as demonstrated in significant differences in the diagnostic management of pediatric Celiac Disease (CD) between European and North American practitioners.

Methods

We use retrospective clinical cohorts of 27,868 serum tissue transglutaminase (tTG) immunoglobulin A levels and 7907 upper gastrointestinal endoscopy pathology reports to create a dataset of 793 pathology reports with matching tTG results between July 1 of 2014 and July 1 of 2018. We use this dataset to characterize histopathological findings in the duodenum, stomach and esophagus of patients as a function of serum tTG levels. In addition, we use the dataset to estimate the local and national cost of endoscopies performed in patients with serum tTG levels greater than 10 times the upper limit of normal.

Results

Using evidence from a US tertiary care center, we show that in the cohort of pediatric patients with high pre-test probability of CD as determined by serum tTG levels, biopsy provides no additional diagnostic value for CD, and that it counter-intuitively introduces diagnostic uncertainty in a number of patients. We estimate that using the European diagnostic algorithms could avoid between 4891 and 7738 pediatric endoscopies per year in the US for evaluation of CD.

Conclusions

This study considers the North American and European management guidelines for the diagnosis of pediatric CD and highlights the slow adoption in North America of evidence-based algorithms developed and applied in Europe for triage of endoscopy and biopsy. We suggest that system dynamics influences that help maintain the status quo in North America include a variety of social and economic factors in addition to medical evidence. This work contributes to the growing body of evidence that the dynamics that largely favor maintaining status quo management policies in a variety of systems extend to clinical medicine and potentially influence clinical decisions at the level of individual patients and the population.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12913-020-05815-0.

[Diagnosis of celiac disease in clinical practice: present and future]

INTRODUCTION

European guidelines for the diagnosis of celiac disease (CD) have been updated in 2020. The primary objective was to review the compliance with the diagnostic criteria for CD, according to ESPGHAN 2012. Secondarily, to describe the clinical characteristics of the patients and to assess the changes that would be implied by the application of the new 2020 criteria.

PATIENTS AND METHODS

Retrospective multicenter study in which 10 centers participated. Patients from 0 to 16 years old with a new diagnosis of CD in 2018-2019 were included. Clinical, serological variables and the performance of intestinal biopsy (IB) were collected.

RESULTS

163 patients were included (57% female) with a median age of 7.6 years (SD 4.4). The form of presentation was: 47.8% classical, 30.7% no classical and 21.5% asymptomatic, with differences depending on age. Total IgA and anti-transglutaminase IgA antibodies were performed in all centers as the first diagnostic step. IgA anti-endomysial antibodies (EMA) were performed in 80%, and HLA haplotype in 95%. Of the total, 78 cases (47.9%) met criteria for not performing intestinal biopsy (IB). IB was indicated in the remaining 85 patients, but was not performed in 29 cases (17.8%). The performance of IB was lower in the secondary hospitals than in the tertiary ones (p < 0.05). If we applied the ESPGHAN 2020 criteria, we would disregard the HLA study, and 21 more patients would not have required IB (going from 47.9% to 60.7% of the total).

CONCLUSIONS

Discrepancies are observed in the application of the ESPGHAN 2012 diagnostic criteria due to the different accessibility to EMA and endoscopic IB in secondary centers. With the ESPGHAN-2020 criteria, around 60% of patients will be able to be diagnosed without IB, provided that the determination of EMA is ensured.

Role of HLA-DQ typing and anti-tissue transglutaminase antibody titers in diagnosing celiac disease without duodenal biopsy in type 1 diabetes: A study of the population-based pediatric type 1 diabetes cohort of Western Australia

AIM

The primary aim of the present study was to determine if it is cost effective to use human leukocyte antigen (HLA) typing as a first-line screening test for celiac disease (CD) in children with type 1 diabetes (T1D), as recommended by the European Society of Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN). The second aim was to investigate whether anti-tissue transglutaminase IgA (anti-tTGA) antibodies can be used to diagnose CD without the need for a confirmatory duodenal biopsy in T1D.

METHODS

Data for all T1D patients aged <18 years, who attended the diabetes clinics in Western Australia up to June 2017, were extracted from the Western Australian Children's Diabetes Database (WACDD) and analyzed for their demographic data and CD permissive HLA alleles (DQ2, DQ8, and DQ7). For T1D patients already diagnosed with CD, the mode of diagnosis of CD, anti-tTGA titers, and CD permissive HLA alleles were analyzed.

RESULTS

Of the 936 eligible T1D patients identified, HLA-DQ typing was available for 551 (59%). Of these 551 patients, 504 (91.2%) were positive for celiac permissive HLA alleles. Eight percent (n = 75) of the T1D patients had a co-diagnosis of CD. High anti-tTGA titers were observed in those who were diagnosed with a positive duodenal biopsy.

CONCLUSION

HLA-DQ typing is not cost effective as a first-line screening test for CD in T1D patients because of over-representation of CD permissive HLA alleles in this group. Anti-tTGA titers may be useful in diagnosing CD in T1D without duodenal biopsy, as high levels were found to be strongly predictive of CD.

Tissue Transglutaminase Antibody and Its Association with Duodenal Biopsy in Diagnosis of Pediatric Celiac Disease

PURPOSE

This study aimed to evaluate a possible association between the anti-tissue transglutaminase antibody (anti-tTG) titer and stage of duodenal mucosal damage and assess a possible cut-off value of anti-tTG at which celiac disease (CD) may be diagnosed in children in conjunction with clinical judgment.

METHODS

This observational study was conducted at a gastroenterology clinic in a tertiary hospital from April 2012 to May 2013. Seventy children between 6-months and 18-years-old with suspected CD underwent celiac serology and duodenal biopsy. Statistical analyses were done using SPSS 16. Diagnostic test values were determined for comparing the anti-tTG titer with duodenal biopsy. An analysis of variance and Tukey-Kramer tests were performed for comparing the means between groups. A receiver operating characteristics curve was plotted to determine various cut-off values of anti-tTG.

RESULTS

The mean antibody titer increased with severity of Marsh staging (p<0.001). An immunoglobulin (Ig) A-tTG value at 115 AU/mL had 76% sensitivity and 100% specificity with a 100% positive predictive value (PPV) and 17% negative predictive value (NPV) for diagnosis of CD (p<0.001, 95% confidence interval [CI], 0.75-1).

CONCLUSION

There is an association between the anti-tTG titer and stage of duodenal mucosal injury in children with CD. An anti-tTG value of 115 AU/mL (6.4 times the upper normal limit) had 76% sensitivity, 100% specificity, with a 100% PPV, and 17% NPV for diagnosing CD (95% CI, 0.75-1). This cut-off may be used in combination with clinical judgment to diagnose CD.

Comparison of non-invasive tests with invasive tests in the diagnosis of celiac disease

BACKGROUND/AIMS

Today, invasive diagnostic tests are necessary for definite diagnosis of adult celiac disease (CD). However, in selected children patients, the need for invasive tests is ceased. In this study, we evaluated adult patients according to the ESPGHAN (European Pediatric Gastroenterology Hepatology and Nutrition Society) criteria.

METHODS

Thirty-nine patients (aged 17-66) with symptoms of CD were included. Serum samples were tested for total IgA, tTG-IgA (antitissue transglutaminase), tTG-IgG, DGP-IgA (antideamidated gliadin peptide), DGP-IgG, and EMA (endomysial antibodies). HLA-DQ typing was studied with PCR-SSP (sequence-specific primers) method. Biopsy samples were evaluated according to Marsh scoring.

RESULTS

In CD patients, 71.4% (15/21) of the patients were diagnosed without biopsy according to the EPSGHAN criteria but when ESPGHAN's IgA tTG threshold value for children was taken into consideration (>200 IU/mL), the sensitivity decreased to 81%. Celiac disease diagnosed and control groups were compared in terms of HLA tissue types. DQ2.5 homozygous or DQ2.5/DQ2.2 was significantly higher in CD group, and DQ2- or DQ8-negative HLA tissue type was significantly higher in control group.

CONCLUSION

When serological tests, HLA typing, and clinical symptoms are all in favor of CD, biopsy may not be performed in selected adult CD patients.

Can High Titres of Anti Tissue Transglutaminase Antibodies Reduce the Need for Intestinal Biopsy for Diagnosis of Celiac Disease?

Traditionally small intestinal biopsy has been considered a gold standard for the diagnosis of celiac disease (CD). But now data has shown that serological markers like anti-tissue-transglutaminase antibodies (tTGA) can be used to make the diagnosis with great sensitivity and specificity. The objective of the present study was to evaluate whether patients with high probability of CD and high titre of tTGA, have a high probability of intestinal damage and may not require biopsy for final diagnosis. All the cases with tTGA levels ≥15 IU/ml and who subsequently underwent biopsy from July 2010 to June 2013 were selected. Histopathological findings graded as per Marsh classification were correlated with serum tTGA levels. Grade 3 lesions were considered diagnostic for the disease. Out of total 731 patients 470 had serum tTGA levels >100 IU/ml and 261 patients had <100 IU/ml. Highest levels of tTGA (219.3 IU/ml) were seen in grade 3c which was >12 times the normal cutoff value. Mean serum tTGA in higher histological grade i.e. 3 (3a, 3b, 3c) was 186.7 IU/ml (>12 times the normal cut off value) as compared to grade 1 which was 108.9 IU/ml (>7 times the normal cut off value). Using a tTGA cutoff value of 70 IU/ml, sensitivity was found to be 83.9% while specificity was 56.10% with an overall accuracy of 77.7%. This study confirms that a small intestinal biopsy is not always necessary for the diagnosis of CD in symptomatic patients with high tTGA levels (>70 IU/ml).

Self-reported dietary adherence, disease-specific symptoms, and quality of life are associated with healthcare provider follow-up in celiac disease

Background

The only treatment for celiac disease (CeD) is a lifelong gluten-free diet (GFD). The restrictive nature of the GFD makes adherence a challenge. As an integral part of CeD management, multiple professional organizations recommend regular follow-up with a healthcare provider (HCP). Many CeD patients also participate in patient advocacy groups (PAGs) for education and support. Previous work found that follow-up of CeD patients is highly variable. Here we investigated the self-reported factors associated with HCP follow-up among individuals diagnosed with CeD who participate in a PAG.

Methods

We conducted a survey of members of Beyond Celiac (a PAG), collecting responses from 1832 U.S. adults ages 19–65 who reported having CeD. The survey queried HCP follow-up related to CeD and included validated instruments for dietary adherence (CDAT), disease-specific symptoms (CSI), and quality of life (CD-QOL).

Results

Overall, 27% of respondents diagnosed with CeD at least five years ago reported that they had not visited an HCP about CeD in the last five years. The most frequent reason for not visiting an HCP was “doing fine on my own” (47.6%). Using multiple logistic regression, we identified significant associations between whether a respondent reported visiting an HCP about CeD in the last five years and the scores for all three validated instruments. In particular, as disease-specific symptoms and quality of life worsened, the probability of having visited an HCP increased. Conversely, as dietary adherence worsened, the probability decreased.

Conclusions

Our results suggest that many individuals with CeD manage their disease without ongoing support from an HCP. Our results thus emphasize the need for greater access to high quality CeD care, and highlight an opportunity for PAGs to bring together patients and HCPs to improve management of CeD.

Electronic supplementary material

The online version of this article (10.1186/s12876-017-0713-7) contains supplementary material, which is available to authorized users.

Accuracy in Diagnosis of Celiac Disease Without Biopsies in Clinical Practice

BACKGROUND & AIMS

The guidelines of the European Society of Pediatric Gastroenterology, Hepatology, and Nutrition allow for diagnosis of celiac disease without biopsies in children with symptoms and levels of immunoglobulin A against tissue-transglutaminase (TGA-IgA) 10-fold or more the upper limit of normal (ULN), confirmed by detection of endomysium antibodies (EMA) and positivity for HLA-DQ2/DQ8. We performed a large, international prospective study to validate this approach.

METHODS

We collected data from consecutive pediatric patients (18 years or younger) on a gluten-containing diet who tested positive for TGA-IgA from November 2011 through May 2014, seen at 33 pediatric gastroenterology units in 21 countries. Local centers recorded symptoms; measurements of total IgA, TGA, and EMA; and histopathology findings from duodenal biopsies. Children were considered to have malabsorption if they had chronic diarrhea, weight loss (or insufficient gain), growth failure, or anemia. We directly compared central findings from 16 antibody tests (8 for TGA-IgA, 1 for TGA-IgG, 6 for IgG against deamidated gliadin peptides, and 1 for EMA, from 5 different manufacturers), 2 HLA-DQ2/DQ8 tests from 2 manufacturers, and histopathology findings from the reference pathologist. Final diagnoses were based on local and central results. If all local and central results were concordant for celiac disease, cases were classified as proven celiac disease. Patients with only a low level of TGA-IgA (threefold or less the ULN) but no other results indicating celiac disease were classified as no celiac disease. Central histo-morphometry analyses were performed on all other biopsies and cases were carefully reviewed in a blinded manner. Inconclusive cases were regarded as not having celiac disease for calculation of diagnostic accuracy. The primary aim was to determine whether the nonbiopsy approach identifies children with celiac disease with a positive predictive value (PPV) above 99% in clinical practice. Secondary aims included comparing performance of different serological tests and to determine whether the suggested criteria can be simplified.

RESULTS

Of 803 children recruited for the study, 96 were excluded due to incomplete data, low level of IgA, or poor-quality biopsies. In the remaining 707 children (65.1% girls; median age, 6.2 years), 645 were diagnosed with celiac disease, 46 were found not to have celiac disease, and 16 had inconclusive results. Findings from local laboratories of TGA-IgA 10-fold or more the ULN, a positive result from the test for EMA, and any symptom identified children with celiac disease (n = 399) with a PPV of 99.75 (95% confidence interval [CI], 98.61-99.99); the PPV was 100.00 (95% CI, 98.68-100.00) when only malabsorption symptoms were used instead of any symptom (n = 278). Inclusion of HLA analyses did not increase accuracy. Findings from central laboratories differed greatly for patients with lower levels of antibodies, but when levels of TGA-IgA were 10-fold or more the ULN, PPVs ranged from 99.63 (95% CI, 98.67-99.96) to 100.00 (95% CI, 99.23-100.00).

CONCLUSIONS

Children can be accurately diagnosed with celiac disease without biopsy analysis. Diagnosis based on level of TGA-IgA 10-fold or more the ULN, a positive result from the EMA tests in a second blood sample, and the presence of at least 1 symptom could avoid risks and costs of endoscopy for more than half the children with celiac disease worldwide. HLA analysis is not required for accurate diagnosis. Clinical Trial Registration no: DRKS00003555.

Correlation of Tissue Transglutaminase with Modified Marsh Grading in Celiac Disease: A Prospective Cohort Study

OBJECTIVE

To find out correlation between serum anti-tissue transglutaminase immunoglobulin-A (tTGA) levels and Marsh grading on duodenal histopathology in Celiac disease (CD).

METHODS

In a prospective cohort study, a total of 52 symptomatic patients between age group of 2-18 y were enroled. All enroled patients were subjected to upper GI endoscopy by an experienced endoscopist. Two biopsies each from the bulb (D1) and second part (D2) of the duodenum were taken and Marsh grading was performed by a single experienced pathologist. Serum tTGA levels were also performed to find out correlation between serum tTGA levels and Marsh grading.

RESULTS

The mean age of the patients was 8.21 ± 3.45 y (Range: 2-16 y). Anemia was the most common non-gastrointestinal (GI) sign and was present in 73% of the cases. However the authors could not find out any significant association between Marsh grading and hemoglobin levels (r = 0.32, p > 0.05). Serum tTGA levels were found to be positively correlated with Marsh grading (Spearmen correlation coefficient ρ = 0.74, p 0.000). Significant differences were found in tTGA levels between different Marsh gradings (ANOVA test) (p 0.000). Receiver-operator curve (ROC) analysis cut-off value of serum tTGA for predicting villous atrophy was 178.8 (nine times of cut-off value) with sensitivity of 100% and specificity of 85.7%.

CONCLUSIONS

Serum tTGA levels can be used to predict villous atrophy and biopsy may be avoided in strongly suspected cases with more than 9 times of cut-offs.

Coeliac disease: further evidence that biopsy is not always necessary for diagnosis

OBJECTIVES

Growing evidence supports the view that the diagnosis of coeliac disease (CD) can be made by serological tests alone, although this approach is still not widely accepted. We previously showed in retrospective and prospective studies that in adults an IgA-tissue transglutaminase antibody cut-off can be defined above which the positive predictive value for CD is 100%. Following a change in the analytical method for measuring the antibody, our objectives were to re-examine this finding in a larger series of adults to ascertain whether a diagnosis of CD can be reliably made in a proportion of patients without the need for small bowel biopsy and to re-evaluate the diagnostic guidelines used in our centre.

PATIENTS AND METHODS

A retrospective analysis was done in an unselected series of 270 adult patients who had small bowel biopsies and serum IgA-tissue transglutaminase antibody levels measured from 2009 to 2014.

RESULTS

At an IgA-tissue transglutaminase antibody cut-off greater than 45 U/ml (>8×upper limit of normal+2SDs) the positive predictive value for CD in this cohort was 100%; 40% of cases were above this cut-off.

CONCLUSION

We have verified that a diagnosis of CD can be reliably made in a high proportion of adults based on serology alone using the IgA-tissue transglutaminase antibody method specified. These results add to the body of evidence that small bowel biopsy should no longer be considered mandatory for the diagnosis of CD. On the basis of these results the diagnostic guidelines in our centre have been modified.

Identification of Pediatric Patients With Celiac Disease Based on Serology and a Classification and Regression Tree Analysis

BACKGROUND & AIMS

Celiac disease is detected using serology and endoscopy analyses. We used multiple statistical analyses of a geographically isolated population in the United States to determine whether a single serum screening can identify individuals with celiac disease.

METHODS

We performed a retrospective study of 3555 pediatric patients (18 years old or younger) in the intermountain West region of the United States from January 1, 2008, through September 30, 2013. All patients had undergone serologic analyses for celiac disease, including measurement of antibodies to tissue transglutaminase (TTG) and/or deamidated gliadin peptide (DGP), and had duodenal biopsies collected within the following year. Modified Marsh criteria were used to identify patients with celiac disease. We developed models to identify patients with celiac disease using logistic regression and classification and regression tree (CART) analysis.

RESULTS

Single use of a test for serum level of IgA against TTG identified patients with celiac disease with 90% sensitivity, 90% specificity, a 61% positive predictive value (PPV), a 90% negative predictive value, and an area under the receiver operating characteristic curve value of 0.91; these values were higher than those obtained from assays for IgA against DGP or IgG against TTG plus DGP. Not including the test for DGP antibody caused only 0.18% of celiac disease cases to be missed. Level of TTG IgA 7-fold the upper limit of normal (ULN) identified patients with celiac disease with a 96% PPV and 100% specificity. Using CART analysis, we found a level of TTG IgA 3.2-fold the ULN and higher to most accurately identify patients with celiac disease (PPV, 89%). Multivariable CART analysis showed that a level of TTG IgA 2.5-fold the ULN and higher was sufficient to identify celiac disease in patients with type 1 diabetes (PPV, 88%). Serum level of IgA against TTG in patients with versus those without trisomy 21 did not affect diagnosis predictability in CART analysis.

CONCLUSIONS

In a population-based study, we found that serum level of IgA against TTG can identify patients with celiac disease with PPVs of about 90%. Predictive values increase greatly when levels are markedly above the ULN or when the assay is used in combination with other variables. Measurement of IgG against TTG or DGP does not increase the accuracy of detection of celiac disease based against TTG IgA levels. There is a low risk of false-positive results from serologic analysis in patients with type I diabetes or persistent increases in antibody against TTG on repeat testing.

Celiac disease: a clinical review

Celiac disease (CD) is an immune-mediated inflammatory enteropathy triggered by gluten exposure in genetically susceptible individuals. It has a high prevalence approaching 1% of the US population. A high index of suspicion is warranted to diagnose CD as frequently patients present with extraintestinal or atypical manifestations. CD is diagnosed by a combination of serum serologies and duodenal biopsies. The majority of patients will respond to a lifelong gluten-free diet which is the cornerstone of therapy. Complications such as refractory CD, ulcerative jejunoileitis, enteropathy associated T-cell lymphoma and small bowel adenocarcinoma occur in a minority of patients.

Prediction of esophageal and gastric histology by macroscopic diagnosis during upper endoscopy in pediatric celiac disease

AIM

To determine the sensitivity of macroscopic appearance for predicting histological diagnosis at sites other than duodenum in pediatric celiac disease (CD).

METHODS

Endoscopic and histologic findings in pediatric patients undergoing upper endoscopy for first-time diagnosis of CD at Stollery Children’s Hospital from 2010-2012 were retrospectively reviewed.

RESULTS

Clinical charts from 140 patients were reviewed. Esophageal and gastric biopsies were taken in 54.3% and 77.9% of patients, respectively. Endoscopic appearance was normal in the esophagus and stomach in 75% and 86.2%. Endoscopic esophageal diagnoses were eosinophilic esophagitis (EE) (11.8%), esophagitis (7.9%), glycogenic acanthosis (1.3%) and non-specific abnormalities (3.9%). Endoscopic gastric diagnoses were gastritis (8.3%), pancreatic rest (0.9%), and non-specific abnormalities (4.6%). Histology was normal in 76.3% of esophageal and 87.2% of gastric specimens. Abnormal esophageal histology was EE (10.5%), esophagitis (10.5%), glycogenic acanthosis (1.3%) and non-specific (1.3%). Gastritis was reported in 12.8% of specimens. Sensitivity and specificity of normal endoscopy for predicting normal esophageal histology was 86.2% and 61.1%, and for normal gastric histology was 87.4% and 21.4%.

CONCLUSION

In the absence of macroscopic abnormalities, routine esophageal and gastric biopsy during endoscopy for pediatric CD does not identify major pathologies. These findings have cost and time saving implications for clinical practice.

Tissue Transglutaminase Levels Are Not Sufficient to Diagnose Celiac Disease in North American Practices Without Intestinal Biopsies

BACKGROUND

Celiac serology is crucial for the diagnosis of celiac disease in children. The American guideline for celiac disease in children suggested that positive serology should be followed by confirmatory intestinal histology. The relationship between high tissue transglutaminase titers and celiac disease in children has not been well investigated in children from North America.

AIMS

In the present study, we investigated whether different tissue transglutaminase titers in symptomatic children could predict celiac disease without the confirmation of intestinal histology.

METHODS

Data from biopsy confirmed celiac children were collected from four different clinics in North America. Clinical, serological, histological, and follow-up data were collected. The accuracy rates of various tissue transglutaminase titers to predict celiac disease in children were calculated.

RESULTS

The data from 240 children were calculated. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rate of tissue transglutaminase titers at ≥10× upper limit of normal were 75.4, 48.8, 87.7, 29.0, and 70.8 %, respectively. Similar data were noted in the other tissue transglutaminase titers (≥3× upper limit of normal, >100 U/ml, or >100 U/ml and >10× upper limit of normal).

CONCLUSIONS

The positive predictive value of tissue transglutaminase titers at ≥3× upper limit of normal or higher was too low to predict celiac disease in children. Our data suggested that in routine clinical practice, high titers of tissue transglutaminase are not sufficient to diagnose celiac disease in North American children without intestinal biopsies.

Correlation Between Cut-off Level of Tissue Transglutaminase Antibody and Marsh Classification

BACKGROUND

Duodenal biopsy is required for diagnosis of celiac disease in adults, although some studies have suggested adequate accuracy of serology alone.

Objective: We aimed to assess the correlation between anti-tissue transglutaminase (tTG) titer and pathological findings and to define the specific level of tTG for predicting celiac disease in adults without the need for biopsy sampling.

METHODS

This descriptive study was done on 299 participants. The tTG titer and pathological findings of duodenal biopsy samples were used for this study. Analysis of Receiver operating characteristic (ROC) curve was used to find a cut-off point of anti-tTG antibody for mucosal atrophy.

RESULTS

Mean tTG titers was significantly higher in patients graded as Marsh III≥ 3 (p=0.023). ROC curve analysis showed 89.1% sensitivity for cut-off point≥76.5 IU/mL of anti-tTG. For Marsh≥ II, specificity was 28% and positive predictive value was 91%.CON

CLUSION

There is a linear correlation between increasing tTG level and Marsh I to III. Specificity of tTG titer more than 200 was 100% for Marsh >2.

Identification of a serum transglutaminase threshold value for the noninvasive diagnosis of symptomatic adult celiac disease patients: a retrospective study

BACKGROUND

A celiac disease (CD) diagnosis is based on duodenal histology, with the exception of children showing anti-tissue transglutaminase (anti-tTG) serum levels exceeding ten times the cut-off. Our aim was to reproduce this simplified approach in adults, identifying an anti-tTG threshold value useful to diagnose CD without endoscopic procedures.

METHODS

A total of 671 adult CD patients were subjected to blood sampling to determine anti-tTG serum levels, as well as to endoscopy with biopsy to perform duodenal histology. The anti-tTG serum levels/cut-off ratio was compared with the degree of duodenal lesions.

RESULTS

Anti-tTG serum levels/cut-off ratio determined in patients with type IIIc was significantly higher than that measured in patients with type IIIb (p < 0.001), IIIa (p < 0.001), II (p < 0.05) and 0 (p < 0.001) of Marsh-Oberhuber histological classification. A significant correlation (r = 0.297, p < 0.0001) was found between the anti-tTG serum levels/cut-off ratio and the degree of duodenal lesions. The anti-tTG serum levels/cut-off ratio was classified as an accurate parameter (AUC = 0.715, p < 0.0001), with the best diagnostic performance obtained considering the threshold value >3.6 (sensitivity = 76.8 %, PPV = 97.2 %).

CONCLUSIONS

The anti-tTG serum levels/cut-off ratio correlates with the degree of duodenal lesions and, if used with the threshold value >3.6, could avoid endoscopy with biopsy in about 75 % of seropositive adults waiting for CD diagnosis. However, since this procedure could also imply CD diagnosis in almost 3 % of seropositive patients with normal villous architecture, a consensus opinion is needed to suggest its use in the diagnosis of adult CD.

Association of Tissue Transglutaminase Antibody Titer with Duodenal Histological Changes in Children with Celiac Disease

Celiac disease is usually diagnosed by demonstrating gluten enteropathy in small bowel biopsy. Celiac specific antibodies are used as an initial screening test. The goal of this study is to test the relationship of the anti-tTG titer and severity of histological changes in Jordanian children with celiac disease. Method. The medical records of 81 children who had elevated anti-tTG titer and had duodenal biopsies available were retrospectively reviewed. Result. Assessing the association of anti-tTG titer with duodenal histopathological changes, 94% of those with high anti-tTG titer (≥180 U/mL) had histological evidence of celiac disease. There was statistically significant positive association between high anti-tTG titer and Marsh grading as 82% of patients with Marsh III had high anti-tTG titer (Chi² 18.5; P value 0.00; Odds Ratio 8.5). The fraction of patients with Marsh III who were correctly identified as positive by anti-tTG titer ≥ 180 U/mL was high (sensitivity = 81.6). Moreover, the fraction of patients with anti-tTG titer ≥ 180 U/mL who had Marsh III was also high (positive predictive value = 78.4). Conclusion. Anti-tTG titer ≥ 180 U/mL had significant positive association with Marsh III histopathological changes of celiac disease.

Intraepithelial lymphocytes subsets in different forms of celiac disease

AIM

The enumeration of intraepithelial lymphocytes subsets (total, γδ, and CD3(-) IELs) by flow cytometry (FCM), named as IEL lymphogram, constitutes a useful tool for celiac disease (CD) diagnosis. The aim of this study was to quantify IELs by FCM and their diagnostic value to differentiate active, silent and potential CD.

METHODS

Prospective study of 60 active and 20 silent CD patients, and 161 controls in which duodenal biopsy and IEL quantification by FCM was performed.

RESULTS

Active and silent CD patients had significant higher levels of both total and γδ IELs than absent CD patients (P < 0.0001 and P < 0.0001, P = 0.012 and P < 0.011; respectively). Active and silent CD patients had significant lower levels of CD3(-) IELs than absent CD patients (P < 0.047 and P < 0.009, respectively). Moreover, they were lower in silent than in active CD patients (P = 0.002). Changes of IELs subsets were more marked in children than adults active CD. The optimal IEL lymphogram cut off values for active CD diagnosis were: ≥10, ≥15 and ≤9 %, and with better performance characteristics for silent CD: ≥ 11, ≥10 and ≤5 %.

CONCLUSION

The evaluation of IELs subsets by FCM is useful to confirm diagnosis of active and silent CD.

A Canadian Study toward Changing Local Practice in the Diagnosis of Pediatric Celiac Disease

Background. The European Society for Pediatric Gastroenterology, Hepatology and Nutrition endorses serological diagnosis (SD) for pediatric celiac disease (CD). The objective of this study was to pilot SD and to prospectively evaluate gastrointestinal permeability and mucosal inflammation at diagnosis and after one year on the gluten-free diet (GFD). We hypothesized that SD would be associated with similar short term outcomes as ED. Method. Children, 3-17 years of age, referred for possible CD were eligible for SD given aTTG level ≥200 U/mL, confirmed by repeat aTTG and HLA haplotypes. Gastrointestinal permeability, assessed using sugar probes, and inflammation, assessed using fecal calprotectin (FC), at baseline and after one year on a GFD were compared to patients who had ED. Results. Enrolled SD (n = 40) and ED (n = 48) patients had similar demographics. ED and SD groups were not different in baseline lactulose: mannitol ratio (L : M) (0.049 versus 0.034; p = 0.07), fractional excretion of sucrose (%FES; 0.086 versus 0.092; p = 0.44), or fecal calprotectin (FC; 89.6 versus 51.4; p = 0.05). At follow-up, urine permeability improved and was similar between groups, L : M (0.022 versus 0.025; p = 0.55) and %FES (0.040 versus 0.047; p = 0.87) (p > 0.05). FC improved but remained higher in the SD group (37.1 versus 15.9; p = 0.04). Conclusion. Patients on the GFD showed improved intestinal permeability and mucosal inflammation regardless of diagnostic strategy. This prospective study supports that children diagnosed by SD have resolving mucosal disease early after commencing a GFD.

The Spectrum of Differences between Childhood and Adulthood Celiac Disease

An old saying states that ''children are not little adults" and this certainly holds true for celiac disease, as there are many peculiar aspects regarding its epidemiology, diagnosis, clinical presentations, associated diseases, and response to treatment in pediatric compared to adult populations, to such an extent that it merits a description of its own. In fact, contrary to the past when it was thought that celiac disease was a disorder predominantly affecting childhood and characterized by a malabsorption syndrome, nowadays it is well recognized that it affects also adult and elderly people with an impressive variability of clinical presentation. In general, the clinical guidelines for diagnosis recommend starting with specific serologic testing in all suspected subjects, including those suffering from extraintestinal related conditions, and performing upper endoscopy with appropriate biopsy sampling of duodenal mucosa in case of positivity. The latter may be omitted in young patients showing high titers of anti-transglutaminase antibodies. The subsequent management of a celiac patient differs substantially depending on the age at diagnosis and should be based on the important consideration that this is a lifelong condition.

Are ESPGHAN "biopsy-sparing" guidelines for celiac disease also suitable for asymptomatic patients?

OBJECTIVES

In 2012, European Society of Pediatric Gastroenterology, Hepatology, and Nutrition published novel guidelines on celiac disease (CD) diagnosis. Symptomatic children with serum anti-transglutaminase (anti-tTG) antibody levels ≥10 times upper limit of normal (ULN) could avoid duodenal biopsies after positive HLA test and serum anti-endomysial antibodies (EMAs). So far, both asymptomatic and symptomatic patients with anti-tTG titer <10 times ULN should undergo upper endoscopy with duodenal biopsies to confirm diagnosis. The aim of this study was to assess the accuracy of serological tests to diagnose CD in asymptomatic patients.

METHODS

We retrospectively reviewed data of 286 patients (age range: 10 months to 17 years) with CD diagnosis based on elevated titer of anti-tTG, EMA positivity, and histology. All patients were distinguished between symptomatic and asymptomatic; histological lesions were graded according to the Marsh-Oberhuber (MO) criteria. Fisher exact test was applied to analyze both groups in terms of diagnostic reliability of serological markers.

RESULTS

A total of 196 patients (68.53%) had anti-tTG titers ≥10 times ULN. Among them, a group of 156 patients (79.59%) also had symptoms suggestive of CD ("high-titer" symptomatic); of these, 142 patients (91.02%) showed severe lesion degree (3a, 3b, 3c MO). Conversely, 40 out of 196 patients (20.40%) were asymptomatic ("high-titer" asymptomatic) and 37 patients (92.5%) of them showed severe lesion degree (3a, 3b, 3c MO). No difference in histological damage was found between "high-titer" symptomatic and "high-titer" asymptomatic children (Fisher exact test, P=1.000).

CONCLUSIONS

If confirmed in large multicenter prospective studies, the "biopsy-sparing" protocol seems to be applicable to both symptomatic and asymptomatic patients with anti-tTG titer ≥10 times ULN, positive EMA, and HLA-DQ2/DQ8.

Clinical features of celiac disease: a prospective birth cohort

OBJECTIVES

To investigate clinical features of celiac disease (CD) and their association with risk factors for CD in a genetic risk birth cohort.

METHODS

Children from 6 clinical centers in 4 countries positive for HLA-DR3-DQ2 or DR4-DQ8 were annually screened for tissue transglutaminase antibodies (tTGA) and assessed for symptoms by questionnaires. Associations of symptoms with anthropometrics, known risk factors for CD, tTGA levels, and mucosal lesions in those biopsied were examined.

RESULTS

Of 6706 screened children, 914 developed persistent positive tTGA, 406 underwent biopsies, and 340 had CD. Compared with age-matched tTGA-negative children, those with persistent tTGA were more likely to have symptoms at 2 (34% vs 19%, P < .001) and 3 years of age (28% vs 19%, P = .009) but not at 4 years (27% vs 21%, NS). Z-scores for height, weight, and BMI did not differ between groups. In children with persistent tTGA, having ≥ 1 symptom was associated with family history of CD (odds ratio = 2.59, 95% confidence interval, 1.21-5.57) but not with age, gender, or HLA-DR3-DQ2 homozygosity. At seroconversion, tTGA levels were higher in symptomatic than asymptomatic children (P < .001), in those from CD families (P < .001), and in US participants (P < .001) but not associated with age, gender, or HLA genotype. tTGA levels correlated with severity of mucosal lesions both in symptomatic (r = 0.53, P < .001) and asymptomatic children (r = 0.22, P = .01).

CONCLUSIONS

A majority of children detected with persistent tTGA in screenings are asymptomatic and have normal growth by age 4 years. tTGA levels correlate more strongly with severity of mucosal lesions in symptomatic as compared with asymptomatic children.

Overview of biomarkers for diagnosis and monitoring of celiac disease

Among the adverse reactions caused by wheat, celiac disease (CD) is the longest studied and best-known pathology. The more recently defined non-celiac gluten sensitivity (NCGS) presents with symptoms which are often indistinguishable from CD. Diagnosis of CD is based on serologic, molecular, and bioptic testing. The IgA anti-transglutaminase (tTG) test is considered highly important, as it shows high sensitivity and specificity and its levels correlate to the degree of intestinal damage. Small bowel biopsy can be avoided in symptomatic patients with IgA anti-tTG levels above 10× the manufacturer's cut-off. Recently, tests of anti-deamidated peptides of gliadin (DGP) have replaced classic anti-native gliadin (AGA) tests. DGP assays have a considerably higher diagnostic accuracy than AGA assays, especially in the IgG class, and can replace anti-tTG tests in patients with selective IgA deficiency. The combination of IgG anti-DGP plus IgA anti-tTG assays show greater sensitivity than a single test, with very high specificity. EMA tests have great diagnostic accuracy but are not recommended by all the latest guidelines because they are observer dependent. Biopsy must still be considered the gold standard for CD diagnosis. HLA-DQ genotyping can be used to screen asymptomatic children and in cases of histology/serology disagreement. About half of NCGS patients are DQ2 positive and have IgG AGA. To diagnose NCGS, first CD and wheat allergy must be excluded; then the wheat dependence of symptoms must be verified by a gluten-free diet and subsequent gluten challenge.

The presence of anti-endomysial antibodies and the level of anti-tissue transglutaminases can be used to diagnose adult coeliac disease without duodenal biopsy

BACKGROUND

The new ESPGHAN guidelines for diagnosis of paediatric coeliac disease suggest to avoid biopsy in genetically pre-disposed and symptomatic individuals with positive anti-endomysial antibodies (EMA) and anti-tissue transglutaminases (a-tTG). However, duodenal biopsy remains the gold standard in adult coeliac disease.

AIMS

To establish the cut-off values of a-tTG, which would: predict the presence of duodenal histology (Marsh ≥2) diagnostic for coeliac disease; and predict the presence of villous atrophy (Marsh 3) in adults.

METHODS

We performed an observational prospective study including all consecutive adult patients with suspected coeliac disease. All subjects were tested for EMA and a-tTG. Coeliac disease diagnosis was made in presence of Marsh ≥2, a-tTG >7 U/mL and positive EMA. A ROC curve was constructed to establish the best specificity cut-off of a-tTG levels, which would predict the presence of Marsh ≥2 and Marsh 3 at histology.

RESULTS

The study included 310 patients with positive antibodies. Histology showed Marsh 1 in 8.7%, Marsh 2 in 3.5%, Marsh 3 in 87.7%. The best cut-off value of a-tTG for predicting Marsh ≥2 was 45 U/mL (sensitivity 70%; specificity 100%; PPV 100%; NPV 24.1%); the best cut-off for predicting villous atrophy was 62.4 U/mL (sensitivity 69%, specificity 100%; PPV 100%; NPV 31%).

CONCLUSIONS

The diagnosis of coeliac disease can be reached without histology in adult patients with positive EMA and a-tTG levels >45 U/mL. An a-tTG level >62.4 was diagnostic for villous atrophy. These results could contribute to improving the diagnosis of coeliac disease by allowing for a significant reduction in diagnosis-related costs.

Celiac disease diagnosis: impact of guidelines on medical prescription in France

OBJECTIVE

Celiac disease is a complex autoimmune disease affecting patients of any age, who may present a wide variety of clinical manifestations. Different guidelines for the diagnosis and management of celiac disease have been recently published. The aim of this study was to determine whether the recommendations issued in these guidelines have been adopted by physicians in France when celiac disease was suspected.

METHODS

A total of 5521 physicians were asked to fill in a detailed questionnaire on diagnosing celiac disease to evaluate their medical practice, as to the type of symptoms leading to the suspicion of celiac disease, the prescription of duodenal biopsy or serological tests, the type of serological tests (anti-tissue transglutaminase, anti-endomysium, anti-gliadin and anti-reticulin antibodies, total immunoglobulin A measurement) prescribed to diagnose celiac disease.

RESULTS

The analysis of the responses of 256 general practitioners (GPs), 221 gastroenterologists and 227 pediatricians showed that the protean clinical presentations of celiac disease might be better recognized by gastroenterologists and pediatricians than by GPs. Gastroenterologists asked for duodenal biopsy much more often than GPs and pediatricians when celiac disease was suspected. Serological testing and knowledge of critical markers, prescribed to diagnose celiac disease, differed among GPs, gastroenterologists and pediatricians.

CONCLUSION

Analysis of medical prescriptions showed that the recommendations for celiac disease diagnosis are not necessarily followed by physicians, emphasizing the fact that the impact of national or international guidelines on medical behavior should be evaluated.

Using patients like my patient for clinical decision support: institution-specific probability of celiac disease diagnosis using simplified near-neighbor classification

BACKGROUND

Interpretation of a diagnostic test result requires knowing what proportion of patients with a "similar" result has the condition in question. This information is often not readily available from the medical literature, or may be based on different clinical populations that make it nonapplicable. In certain settings, where correlated screening parameters and diagnostic data are available in electronic medical records, a representation of diagnostic test performance on "patients like my patient" can be obtained.

OBJECTIVE

We sought to integrate patient demographic and physician practice information using a simplified nearest neighbor algorithm. We used this method to illustrate the relationship between tTG IgA test result and duodenal biopsy for celiac disease in a local diagnostic context.

PARTICIPANTS

We used a data set of 1,461 paired tissue transglutaminase (tTG) IgA and definitive duodenal biopsy results from Intermountain Healthcare with data on patient age and ordering physician specialty. This was split into a discovery set of 1,000 and a validation set of 461 paired results.

MAIN MEASURES

Accuracy of the local discovery data set in predicting probability of positive duodenal biopsy and confidence intervals around predicted probability in the test data compared to probabilities of positive biopsy implied from published logistic regression and from published sensitivity and specificity studies.

KEY RESULTS

The near-neighbor method could estimate probability of clinical outcomes with predictive performance equivalent to other methods while adjusting probability estimates and confidence intervals to fit specific clinical situations.

CONCLUSIONS

Data from clinical encounters obtained from electronic medical records can yield prediction estimates that are tailored to the individual patient, local population, and healthcare delivery processes. Local analysis of diagnostic probability may be more clinically meaningful than probabilities inferred from published studies. This local utility may come at the expense of external validity and generalizability.

Symptom positivity is essential for omitting biopsy in children with suspected celiac disease according to the new ESPGHAN guidelines

The aim of this study was to assess the accuracy of serological tests in combination with clinical symptoms for diagnosing celiac disease (CD) according to the new proposed European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) criteria. We retrospectively assessed children and adolescents aged 16 months -19 years who were examined for suspicion of CD (n = 345). Evaluation of clinical symptoms and the presence of tissue transglutaminase (anti-TG-IgA) and endomysial antibodies (EMA-IgA) as well as intestinal biopsies was performed in all patients. Human leukocyte antigens (HLAs) were not included. Among 345 biopsied children, 213 (62 %) children had anti-TG titers >10 times the upper limit of normal (ULN) and positive EMA antibodies. Ninety-nine (29 %) children also had symptoms suggestive of CD in addition to EMA positivity and elevated titers of anti-TG >10 times the ULN. In patients who were asymptomatic, but positive for EMA, and had anti-TG antibodies >10 times the ULN, the specificity of tests for Marsh 2-3 was only 85 %, while in symptomatic patients with the same antibodies levels, the specificity was 99 %. Conclusion: Our results reveal that intestinal biopsies could be omitted in 28 % of patients when the new ESPGHAN guidelines are applied. Due to high accuracy of serological tests in combination with clinical symptoms for diagnosis of CD, the new guideline seems to be applicable even without the use of HLA testing.

Mass population screening for celiac disease in children: the experience in Republic of San Marino from 1993 to 2009

Background

Prevalence of celiac disease in developed countries is assessed about 1:100–1:150. The real prevalence is unknown because mass screenings are expensive and difficult to organize. Moreover celiac disease can affect people at every age and studies on asymptomatic subjects at different ages are not comparable. In this study we wanted to know the real prevalence of celiac disease in children in the Republic of San Marino. We also analysed concordance of different tests used and costs of mass screening.

Methods

The study started in 1993. From 1993 to 1997 children aged 6, 10 and 14 were screened. Since 1997 only children aged 6 were monitored, in order to have a homogeneous population. In fact, every child born since 1980 was taken into account. Children were recruited by classroom lists of students for general paediatric examination. Until 2005 the screening test was based on dosage of antibodies anti-gliadin (AGA) IgA and IgG on venous blood. Since 2006 these tests were replaced by anti-transglutaminase IgA antibodies (ATTG). Anti-endomysial antibodies (EMA) were performed if result of any between either AGA or ATTG tests was positive or borderline; if EMA was positive, then an endoscopy with histological examination was performed to confirm the final diagnosis.

Results

Attendance to paediatric examination was 96%, submission to blood test was 87%. 42 on 5092 (0,8%; 1:125) children resulted affected by celiac disease. Histology always confirmed diagnosis by serology except for two cases. AGA test (until 2005) yielded 28 on 4304 (0,7% 1:143); ATTG test (since 2006) revealed 14 positive cases on 788 (1,8%; 1:55) leading to a larger percentage of diagnosis. EMA antibodies always confirmed positivity of ATTG.

Conclusions

Prevalence of celiac disease in children of Republic of San Marino is comparable to other North-European Countries. Sensitivity of ATTG proved much higher than that of anti-gliadin antibodies. Concordance between ATTG and EMA was 100%. Concordance between serology and histology was approximately 100%. Cost of screening was yearly about 5000 euros (250 children screened every year).

Red cell distribution width can predict intestinal atrophy in selected patients with celiac disease

BACKGROUND

Red cell distribution width (RDW) has been shown as a distinctive marker of mortality and morbidity in a wide spectrum of conditions related to systemic inflammation or deficiency of antioxidant nutrients.

OBJECTIVE

We aimed to investigate the predictive value of RDW in detection of intestinal atrophy in celiac disease (CD).

METHODS

Iron indices and RDW were studied in 49 patients with CD to evaluate the utilization of RDW as a predictive marker for presence of intestinal atrophy.

RESULTS

Sixty-nine percent of patients had iron deficiency at initial presentation and 89% had abnormal RDW defined as >14. Receiver operating characteristics curves of RDW has been found to be a predictive of intestinal atrophy at levels higher than 17.25 (68% sensitivity and 85% specificity). In patients with transglutaminase antibody IgA titers >200 U/l, RDW level >17.75 showed 76% sensitivity and 100% specificity for intestinal atrophy.

CONCLUSIONS

We suggest that RDW can be used as a surrogate marker of atrophy in patients with iron deficiency and suspected CD. In addition, the sensitivity, specificity, negative and positive predictive values of RDW increases when used in combination with high levels of transglutaminase IgA antibody.

Evaluation and management of skeletal health in celiac disease: position statement

OBJECTIVE

To review the evaluation and management of skeletal health in patients with celiac disease (CD), and to make recommendations on screening, diagnosis, treatment and follow-up of low bone mineral density (BMD) in CD patients.

METHODS

A multidisciplinary team developed clinically relevant questions for review. An electronic search of the literature was conducted using the MEDLINE and EMBASE databases from 1996 to 2010. All original studies, reviews and guidelines, both pediatric and adult, were included. A document summarizing the results of the review and proposed recommendations was prepared and underwent multiple revisions until consensus was reached.

RESULTS

At diagnosis, approximately one-third of adult CD patients have osteoporosis, one-third have osteopenia and one-third have normal BMD. Children with CD have low bone mass at diagnosis. Adult and pediatric CD patients are at increased risk of fractures.

DISCUSSION

For adults, serum calcium, albumin, 25(OH) vitamin D3, parathyroid hormone and 24 h urine calcium testing should be performed at diagnosis; patients with 'classic' CD and those at risk for osteoporosis should undergo a dual x-ray absorptiometry scan. An abnormal baseline dual x-ray absorptiometry scan should be repeated one to two years after initiation of a gluten-free diet (GFD). For children, BMD should be assessed one year after diagnosis if GFD adherence is not strict. A GFD is the most important treatment for bone loss. Supplemental antiresorptives may be justified in those who remain at high fracture risk (eg, postmenopausal women, older men) after implementation of a GFD.

CONCLUSION

Current evidence does not support the screening of all CD patients for low BMD at diagnosis. Follow-up BMD assessment should be performed one to two years after initiation of a GFD.

Intestinal biopsy is not always required to diagnose celiac disease: a retrospective analysis of combined antibody tests

Background

The objective of this study was to compare celiac disease (CD)– specific antibody tests to determine if they could replace jejunal biopsy in patients with a high pretest probability of CD.

Methods

This retrospective study included sera from 149 CD patients and 119 controls, all with intestinal biopsy. All samples were analyzed for IgA and IgG antibodies against native gliadin (ngli) and deamidated gliadin peptides (dpgli), as well as for IgA antibodies against tissue transglutaminase and endomysium.

Results

Tests for dpgli were superior to ngli for IgG antibody determination: 68% vs. 92% specificity and 79% vs. 85% sensitivity for ngli and dpgli, respectively. Positive (76% vs. 93%) and negative (72% vs. 83%) predictive values were also higher for dpgli than for ngli. Regarding IgA gliadin antibody determination, sensitivity improved from 61% to 78% with dpgli, while specificity and positive predictive value remained at 97% (P < 0.00001). A combination of four tests (IgA anti-dpgli, IgG anti-dpgli, IgA anti- tissue transglutaminase, and IgA anti-endomysium) yielded positive and negative predictive values of 99% and 100%, respectively and a likelihood ratio positive of 86 with a likelihood ratio negative of 0.00. Omitting the endomysium antibody determination still yielded positive and negative predictive values of 99% and 98%, respectively and a likelihood ratio positive of 87 with a likelihood ratio negative of 0.01.

Conclusion

Antibody tests for dpgli yielded superior results compared with ngli. A combination of three or four antibody tests including IgA anti-tissue transglutaminase and/or IgA anti- endomysium permitted diagnosis or exclusion of CD without intestinal biopsy in a high proportion of patients (78%). Jejunal biopsy would be necessary in patients with discordant antibody results (22%). With this two-step procedure, only patients with no CD-specific antibodies would be missed.

Diagnosis of celiac disease

This article reviews issues related to identifying the appropriate patient to test for celiac disease, the performance characteristics of serologic testing, the role of gene testing for human leukocyte antigen DQ2 and DQ8 haplotypes, and issues related to the performance of small intestinal biopsy. The article concludes with a review of special diagnostic considerations in pediatric patients.

Are positive serum-IgA-tissue-transglutaminase antibodies enough to diagnose coeliac disease without a small bowel biopsy? Post-test probability of coeliac disease

BACKGROUND

It has been suggested that high titres of tTG are associated with elevated positive predictive values (PPV) for celiac disease. However, the PPV of a strongly positive tTG will depend on the celiac disease prevalence in the different risk groups of the disease

AIMS

To assess the PPV of a strongly positive tTG for celiac disease. In addition, to calculate the post-test probability for celiac disease of a strongly positive tTG in a setting of routine clinical practice.

METHODS

145 consecutive celiac disease patients with positive tTG, and with a small bowel biopsy were included. The PPV for different cut-off points of tTG levels for the diagnosis of celiac disease was assessed. In addition, the cut-offs associated with higher PPV were used to calculate the positive likelihood ratio. A simulation in a setting of routine clinical practice was performed to calculate the post-test probability of celiac disease.

RESULTS

No cut-off level was associated with a PPV of 100%. A cut-off of 80 U/mL (11.4×upper normal limit) was associated with the higher PPV value of 98.6%. In the most frequent clinical situations, which in general have a pre-test probability <10%, the post-test probability after having a strongly positive tTG was 90% or less.

CONCLUSIONS

A strongly positive tTG should not be enough to diagnose celiac disease in the most frequent clinical situations, small bowel biopsy remaining as the gold standard in these cases.

Tissue transglutaminase levels above 100 U/mL and celiac disease: A prospective study

AIM: To investigate whether a tissue-transglutaminase antibody (tTGA) level ≥ 100 U/mL is sufficient for the diagnosis of celiac disease (CD).

METHODS: Children suspected of having CD were prospectively included in our study between March 2009 and September 2011. All patients with immune globulin A deficiency and all patients on a gluten-free diet were excluded from the study. Anti-endomysium antibodies (EMA) were detected by means of immunofluorescence using sections of distal monkey esophagus (EUROIMMUN, Luebeck, Germany). Serum anti-tTGA were measured by means of enzyme-linked immunosorbent assay using human recombinant tissue transglutaminase (ELiA Celikey IgA kit Phadia AB, Uppsala, Sweden). The histological slides were graded by a single experienced pathologist using the Marsh classification as modified by Oberhuber. Marsh II and III lesions were considered to be diagnostic for the disease. The positive predictive values (PPVs), negative predictive values (NPVs), sensitivity and specificity of EMA and tTGA along with their 95% CI (for the cut off values > 10 and ≥ 100 U/mL) were calculated using histology as the gold standard for CD.

RESULTS: A total of 183 children were included in the study. A total of 70 (38.3%) were male, while 113 (61.7%) were female. The age range was between 1.0 and 17.6 years, and the mean age was 6.2 years. One hundred twenty (65.6%) patients had a small intestinal biopsy diagnostic for the disease; 3 patients had a Marsh II lesion, and 117 patients had a Marsh III lesion. Of the patients without CD, only 4 patients had a Marsh I lesion. Of the 183 patients, 136 patients were positive for EMA, of whom 20 did not have CD, yielding a PPV for EMA of 85% (95% CI: 78%-90%) and a corresponding specificity of 68% (95% CI: 55%-79%). The NPV and specificity for EMA were 91% (95% CI: 79%-97%) and 97% (95% CI: 91%-99%), respectively. Increased levels of tTGA were found in 130 patients, although only 116 patients truly had histological evidence of the disease. The PPV for tTGA was 89% (95% CI: 82%-94%), and the corresponding specificity was 78% (95% CI: 65%-87%). The NPV and sensitivity were 92% (95% CI: 81%-98%) and 97% (95% CI: 91%-99%), respectively. A tTGA level ≥ 100 U/mL was found in 87 (47.5%) patients, all of whom were also positive for EMA. In all these 87 patients, epithelial lesions confirming CD were found, giving a PPV of 100% (95%CI: 95%-100%). The corresponding specificity for this cut-off value was also 100% (95% CI: 93%-100%). Within this group, a total of 83 patients had symptoms, at least gastrointestinal and/or growth retardation. Three patients were asymptomatic but were screened because they belonged to a group at risk for CD (diabetes mellitus type 1 or positive family history). The fourth patient who lacked CD-symptoms was detected by coincidence during an endoscopy performed for gastro-intestinal bleeding.

CONCLUSION: This study confirms based on prospective data that a small intestinal biopsy is not necessary for the diagnosis of CD in symptomatic patients with tTGA ≥ 100 U/mL.

Screening for celiac disease in children with dental enamel defects

Background. Dental enamel defects (DEDs) are seen in celiac disease (CD). Aim was to detect frequency of CD among such patients. Methods. This study included 140 children with DED. They were tested for CD. Gluten-free diet (GFD) was instituted for CD patients. A cohort of 720, age and sex-matched, normal children represented a control group. Both groups were evaluated clinically. Serum calcium, phosphorus, alkaline phosphatase, serum IgA, and tissue transglutaminase (tTG) IgG and IgA types were measured. Results. CD was more diagnosed in patients with DEDs (17.86%) compared to controls (0.97%) (P < 0.0001). Majority of nonceliac patients showed grade 1 DED compared to grades 1, 2, and 3 DED in CD. Five children had DED of deciduous teeth and remaining in permanent ones. After 1 year on GFD, DED improved better in CD compared to nonceliac patients. Gastrointestinal symptoms did not vary between celiac and nonceliac DED patients. Lower serum calcium significantly predicted CD in this cohort. Conclusion. CD is more prevalent among children with DED than in the general population. These DEDs might be the only manifestation of CD; therefore, screening for CD is highly recommended among those patients especially in presence of underweight and hypocalcemia.

Clinical presentation of celiac disease among pediatric compared to adolescent and adult patients

BACKGROUND

Celiac disease (CD) is being increasingly recognized in adults though a majority of patients continue to be diagnosed in childhood.

AIM

To compare the clinical presentation and profile of newly diagnosed pediatric and adolescent/adult CD patients.

MATERIALS AND METHODS

Retrospective analysis of patients diagnosed with CD between year 1997 and 2007 in the pediatric group, and between year 2000 and 2007 in the adolescent/adult group was done for clinical presentation, endoscopic findings and duodenal histology.

RESULTS

A total of 434 children and 298 adults were studied. The mean age of diagnosis was 6.5 ± 2.5 years (1-11 years) in children and 29.3 ± 13.3 years (6-73 years) in adolescent/adults. The mean duration of symptoms before diagnosis was 3.5 ± 2.5 years in children and 4.9 ± 4.6 years in the latter. Diarrhea as the presenting symptom was seen in 74 % of children and 58.7 % of adolescent/adults. Anemia (on investigations) was seen in 84 % of children and 94 % of adolescent/adults.

CONCLUSIONS

Pediatric patients of CD present more often with typical features than adults. Atypical presentations are more common in adults and the latent period for diagnosis is also longer in adolescent/adults. There is a need for increasing awareness about CD, both among pediatricians and physicians caring for adult patients.