Mass Screening for Celiac Disease: The Autoimmunity Screening for Kids Study

Celiac disease screening in children: evaluating the evidence, benefits, and challenges

Comprehensive screening of the general population is the only approach capable of identifying the majority of cases with celiac disease. In 2023, the Italian Parliament enacted a law to implement nationwide screening for celiac disease and type 1 diabetes. However, critical decisions regarding the target population, optimal timing, and screening methods remain unresolved. Previous observational studies on birth cohorts of children with genetic risk for these conditions have demonstrated that the incidence peaks early in life and is influenced by HLA risk genotypes. This mini-review explores different aspects of screening for celiac disease, presenting the advantages and challenges of identifying children before onset of symptoms. In addition, we summarize the current knowledge and gaps in understanding related to screening programs for celiac disease in children and adolescents and discuss health benefits, psychosocial aspects and cost-effectiveness, and their potential implications for future public health strategies.

Universal capillary screening for chronic autoimmune, metabolic and cardiovascular diseases: feasibility and acceptability of the UNISCREEN study

Background

UNISCREEN is a general population study aiming at evaluating feasibility and acceptability of universal screening for chronic autoimmune (type 1 diabetes and celiac disease) and metabolic/cardiovascular diseases (dysglycemia, type 2 diabetes, dyslipidemia, hypertension) across all age groups using capillary blood sampling by fingerprick to measure disease risk markers.

Methods

UNISCREEN was conducted in the Cantalupo fraction, Cerro Maggiore, Milan, Italy, counting 3,061 inhabitants between 1 and 100 years of age. Participation was voluntary, following a public call. Participants were invited to respond to feasibility and acceptability questionnaires immediately before and after the screening procedures, which included the following: capillary blood drawing for immediate measurement of metabolic parameters (glucose, glycated hemoglobin, total-, HDL- and calculated LDL-cholesterol, triglycerides) and late autoantibody assays; blood pressure measurement; brief consultation with a physician providing feed-back on immediate results and health recommendations. The study was registered as ClinicalTrials.gov NCT05841719.

Results

The study included 1,535 participants (50.1% of local population). A single fingerprick was sufficient for all measurements in 47.1% of cases, while up to two were necessary in 86.9% of cases. Complete glucose and lipid panels were obtained in 1382 participants (90.0%). Sufficient serum for late autoantibody testing was obtained in 99.7% of participants. The questionnaires showed overall satisfaction, with over 90% of participants considering capillary sampling simple and practical, and preferring it to venous sampling. Before screening, 24.0% adults and 31.7% children's parents were worried about the possibility of being diagnosed or identified as being at risk; worries decreased to 21.3 and 23.4%, respectively, after medical consultation. The immediacy of some result communication possibly contributed to reducing the anticipatory anxiety.

Conclusion

The UNISCREEN study shows that universal screening for chronic autoimmune, metabolic and cardiovascular diseases in the general population using capillary blood testing is feasible and acceptable.

Serological testing for celiac disease in children

INTRODUCTION

Celiac disease is one of the most common chronic immune-mediated gastrointestinal conditions, characterized by the presence of disease-specific serum antibodies against self-antigen transglutaminase 2. Even though modern serological assays can identify most untreated celiac disease patients and are also increasingly being used to establish a diagnosis, several challenges are associated with the tests, including a lack of standardization, the variable sensitivity and specificity of commercial assays, and inadequate sensitivity for monitoring adherence to a gluten-free diet.

AREAS COVERED

This narrative review outlines the current use of serological tests in case-finding and screening, as well as in the follow-up of dietary treatment. Additionally, the possible challenges and pitfalls of serological tests, along with future directions, are addressed.

EXPERT OPINION

The excellent accuracy of modern autoantibody tests, especially for greatly elevated levels of transglutaminase 2 antibodies and positive endomysial antibodies, enables using serological testing in establishing a diagnosis. However, better international standardization of the assays is required, the necessity of endomysial antibody testing needs to be further scrutinized, and additional research is needed to improve noninvasive tools for follow-up and to further expand the no-biopsy criteria for celiac disease.

Global Prevalence and Clinical Manifestations of Celiac Disease Among First-Degree Relatives: A Systematic Review and Meta-Analysis

INTRODUCTION

First-degree relatives (FDRs) of patients with celiac disease (CeD) are at high risk for developing CeD. We conducted a systematic review and meta-analysis to estimate CeD prevalence and clinical manifestations by analyzing studies that used the anti-tissue transglutaminase antibody test for screening.

METHODS

In this systematic review with meta-analysis, studies published in PubMed, Web of Science, Embase, and Scopus were searched up to January 11, 2024, using keywords related to CeD and FDRs. Random-effects models were used, with heterogeneity assessed using the Cochran Q test and the I2 statistic performed in STATA 18.

RESULTS

Of 8,764 studies screened, 34 studies involving 10,016 FDRs of patients with CeD were included. The pooled estimates for seroprevalence and the biopsy-confirmed CeD prevalence in FDRs were 11% (95% CI: 9%-13%) and 7% (95% CI: 6%-9%), respectively. Daughters and sisters had the highest prevalence rates at 23% and 14%, compared with sons and brothers at 6% and 9%, respectively. Regional analysis revealed the highest seroprevalence estimates in Hungary (24%) and Cuba (19%), while the highest prevalence of biopsy-confirmed CeD was reported in Serbia (16%) and the United States (15%). Abdominal pain (42%), bloating (39%), and flatulence (38%) were the most common gastrointestinal symptoms, while 34% of FDRs with CeD were asymptomatic. In addition, pallor was the most frequent nongastrointestinal symptom (54%).

DISCUSSION

Approximately 1 in 14 FDRs of patients with CeD is estimated to have CeD, with 1 in 4 daughters, 1 in 7 sisters, 1 in 11 brothers, 1 in 16 sons, and 1 in 20 fathers and mothers could be affected. Routine screening for FDRs could support early detection and management of CeD.

Patient and Community Health Global Burden in a World With More Celiac Disease

Celiac disease is one of the most common life-long disorders worldwide, with a prevalence mostly ranging between 0.7% and 2.9% in the general population and a higher frequency in females and well-defined at-risk groups, such as relatives of affected individuals and patients with autoimmune comorbidities. Increasing clinical detection is facilitated by improving awareness, implementation of a case-finding approach, and serology availability for screening at-risk patients, among other factors. Nevertheless, due to huge clinical variability, many celiac disease cases still escape diagnosis in most countries, unless actively searched by proactive policies. The burden of celiac disease is increasing, as is the need for better longitudinal care. Pediatric screening of the general population could represent the road ahead for an efficient intervention of secondary prevention aimed to reduce the social and health burden of celiac disease. This review analyses the epidemiology of celiac disease continent by continent, discusses current strategies to improve the detection of celiac disease, and highlights challenges related to the burden of celiac disease globally.

Longitudinal screening of HLA-risk and HLA-nonrisk children for celiac disease to age 15 years: CiPiS study

OBJECTIVES

Autoantibodies against tissue transglutaminase (tTG) are serological markers of celiac disease. The aim was to study the applicability of human leukocyte antigen (HLA)-genotyping and tTG autoantibodies in the screening of celiac disease in a longitudinal birth cohort followed to age 15 years.

METHODS

Included were 13,860 HLA-DQ-genotyped children at birth and previously invited to a screening at age 3 and 9 years, respectively. HLA-DQB1*02 and/or DQB1*03:02 (HLA-risk) children were compared with non-HLA-DQB1*02 and non-DQB1*03:02 (HLA-nonrisk) children. The present study reinvited 12,948/13,860 (93.4%) children at age 15 years of whom 1056/2374 (44.5%) participated in screening at both age 3 and 9 years. Both immunoglobulin A (IgA) and G (IgG) autoantibodies against tTG were analyzed separately in radiobinding assays. Persistently tTG autoantibody-positive children were examined with intestinal biopsy to confirm the diagnosis of celiac disease.

RESULTS

At age 3 years, celiac disease was diagnosed in 56/1635 (3.4%) HLA-risk children compared with 0/1824 HLA-nonrisk children (p < 0.001). By age 9 years, celiac disease was diagnosed in 72/1910 (3.8%) HLA-risk children compared with 0/2167 HLA-nonrisk children (p < 0.001). Screening at age 15 years detected 14/1071 (1.3%) HLA-risk children positive for IgA-tTG and/or IgG-tTG of whom 12/1071 (1.1%) remained persistently positive. Among those, 10/1071 (0.9%, 95% confidence interval: 0.4%-1.7%) HLA-risk children were diagnosed with celiac disease compared with 0/1303 HLA-nonrisk children (p < 0.001) and 5/491 (1.0%) were negative in screenings at both 3 and 9 years of age.

CONCLUSIONS

Screening for celiac disease needs to be performed at multiple timepoints to detect all cases but can be restricted to children at HLA-risk.

Home capillary sampling and screening for type 1 diabetes, celiac disease, and autoimmune thyroid disease in a Swedish general pediatric population: the TRIAD study

Objective

To screen a general pediatric population for type 1 diabetes (T1D), celiac disease (CD), and autoimmune thyroid disease (AITD) after home capillary sampling.

Methods

Swedish schoolchildren between 6-9 years and 13-16 years of age were invited to screening by taking a capillary sample at home. Samples were returned by mail and assessed for autoantibodies associated with T1D, CD, and AITD. Persistently autoantibody-positive children were referred for clinical follow-up.

Results

Of 19,593 invited, 3,527 (18.0%) consented to participate and 2,315/3,527 (65.6%) returned a blood sample of sufficient volume. Hemolysis occurred in 830/2,301 (36.1%) samples. After exclusion of 42 children with previously known T1D, CD, or AITD, and two autoantibody-positive children who declined a confirmatory sample, 2,271/19,593 (11.6%) were included. 211/2,271 (9.3%) had persistent autoantibodies: 60/2,271 (2.6%) with T1D autoantibodies, 61/2,271 (2.7%) with CD autoantibodies, and 99/2,271 (4.4%) with AITD autoantibodies; 9/2,271 (0.4%) were autoantibody positive for ≥1 disease. After clinical follow-up, 3/2,271 (0.1%) were diagnosed with T1D, 26/2,271 (1.1%) with CD, and 6/2,271 (0.3%) with AITD. Children with a first-degree relative (FDR) with T1D, CD, and/or AITD, had higher occurrence of autoantibodies compared to children without an FDR (63/344, 18.3%, vs. 148/1,810, 8.2%) (p < 0.0001, OR 2.52, 95% CI 1.83-3.47), and higher occurrence of screening-detected diagnosis (14/344, 4.1%, vs. 21/1,810, 1.2%) (p < 0.0001, OR 3.61, 95% CI 1.82-7.18). Half of these children screened positive for another disease than the FDR.

Conclusion

Screening for T1D, CD, and AITD by home capillary sampling in a Swedish general pediatric population detected autoimmunity in 9.3% and undiagnosed disease in 1.5%.

One-Year Outcomes Among Children Identified With Celiac Disease Through a Mass Screening Program

BACKGROUND & AIMS

Celiac disease (CD) mass screening remains controversial in part because of a paucity of data to support its benefit. The Autoimmunity Screening for Kids study is a mass screening study for pediatric CD and type 1 diabetes in Colorado.

METHODS

This study prospectively follows up children ages 1 to 17 years who screened positive for tissue transglutaminase IgA autoantibodies in the Autoimmunity Screening for Kids study subsequently referred for diagnostic evaluation. Children diagnosed with CD by biopsy or serologic criteria were included in this study. Evaluation at baseline and 12 month follow-up evaluation included demographics, laboratory studies, symptoms, health-related quality of life, anxiety/depression, and gluten-free diet adherence. Paired Student t test, chi-square, and Wilcoxon signed-rank tests compared baseline and follow-up data. For symptom scores, odds of improvement were assessed.

RESULTS

Of the 52 children with CD enrolled, 42 children completed 12-month follow-up evaluation. On the symptom questionnaire completed at diagnostic evaluation, 38 of 42 children reported 1 or more symptoms. CD mean symptom severity and frequency scores improved from baseline to follow-up evaluation (P < .001). Reported health-related quality of life scores improved among caregivers (P = .002). There was no significant change in reported anxiety or depression. Iron deficiency without anemia was common at baseline (21 of 24 children; 87.5%) and normalized at follow-up evaluation (11 of 21 children; 52.3%). Twenty-six of 28 families reported good or excellent gluten-free diet adherence.

CONCLUSIONS

This novel study of children with CD identified through a mass screening program demonstrated improvement in symptoms, quality of life, and iron deficiency after 1 year follow-up evaluation. This demonstrates that there may be benefit to CD mass screening.

Correlations Between Relative Prevalence of Celiac Disease and Sociodemographic Variables in the United States

INTRODUCTION

We evaluated the associations between celiac disease (CD) prevalence and regional sociodemographic variables in the United States.

METHODS

The outcome was CD relative prevalence, defined as number of patients with CD among those in a Medicare registry per 3-digit ZIP code. Linear regression models assessed associations between relative prevalence of CD and sociodemographic variables.

RESULTS

CD relative prevalence was positively correlated with median income, urban area, and proximity to a CD specialty center and negatively correlated with Black race, Latino/Hispanic ethnicity, and median social deprivation index score ( P < 0.01, all).

DISCUSSION

CD relative prevalence is associated with indicators of economic advantage.

Celiac disease symptom profiles and their relationship to gluten-free diet adherence, mental health, and quality of life

BACKGROUND

A subgroup of adults with celiac disease experience persistent gastrointestinal and extraintestinal symptoms, which vary between individuals and the cause(s) for which are often unclear.

METHODS

The present observational study sought to elucidate patterns of persistent symptoms and the relationship between those patterns and gluten-free diet adherence, psychiatric symptoms, and various aspects of quality of life (QOL) in an online sample of adults with celiac disease. U.S. adults with self-reported, biopsy-confirmed celiac disease (N = 523; Mage = 40.3 years; 88% women; 93.5% White) voluntarily completed questionnaires as part of the iCureCeliac® research network: (a) Celiac Symptoms Index (CSI) for physical symptoms and subjective health; (b) Celiac Dietary Adherence Test for gluten-free diet adherence; (c) PROMIS-29, SF-36, and Celiac Disease Quality of Life Survey for psychiatric symptoms and QOL. Symptom profiles were derived using latent profile analysis and profile differences were examined using auxiliary analyses.

RESULTS

Latent profile analysis of CSI items determined a four-profile solution fit best. Profiles were characterized by: (1) little to no symptoms and excellent subjective health (37% of sample); (2) infrequent symptoms and good subjective health (33%); (3) occasional symptoms and fair to poor subjective health (24%); (4) frequent to constant symptoms and fair to poor subjective health (6%). Profiles 2 and 3 reported moderate overall symptomology though Profile 2 reported relatively greater extraintestinal symptoms and Profile 3 reported relatively greater gastrointestinal symptoms, physical pain, and worse subjective health. Profiles differed on anxiety and depression symptoms, limitations due to physical and emotional health, social functioning, and sleep, but not clinical characteristics, gluten-free diet adherence, or QOL. Despite Profile 3's moderate symptom burden and low subjective health as reported on the CSI, Profile 3 reported the lowest psychiatric symptoms and highest quality of life on standardized measures.

CONCLUSIONS

Adults with celiac disease reported variable patterns of persistent symptoms, symptom severity, and subjective health. Lack of profile differences in gluten-free diet adherence suggests that adjunctive dietary or medical assessment and intervention may be warranted. Lower persistent symptom burden did not necessarily translate to better mental health and QOL, suggesting that behavioral intervention may be helpful even for those with lower celiac symptom burden.

Population level screening for celiac disease: is now the time?

PURPOSE OF REVIEW

As incidence and prevalence of celiac disease is increasing, subclinical and asymptomatic presentations are more commonly identified through celiac disease screening. However, the United States Preventive Services Task Force released a statement in 2017 maintaining that there is insufficient evidence to recommend general population screening for celiac disease for asymptomatic individuals. This review summarizes the current available evidence on celiac disease screening.

RECENT FINDINGS

Literature demonstrates that by limiting screening to individuals with recognized symptoms, celiac disease diagnosis is frequently delayed or missed entirely. Most individuals with screening-identified celiac disease have previously unrecognized symptoms that improve through treatment with a gluten-free diet. Screening-identified individuals also demonstrate signs of impaired nutrition, growth, bone health, and quality of life which improve with treatment. Overall, celiac disease screening is viewed favorably by those identified through celiac disease screening programs.

SUMMARY

Individuals with screening-identified celiac disease may still incur complications from untreated disease and receive benefit from treatment with a gluten-free diet. More data is needed to determine the cost effectiveness of different mass screening approaches that incorporate the societal perspective towards screening.

Relationship between gluten availability and celiac disease prevalence: A geo-epidemiologic systematic review

Celiac disease is a global disease requiring genetic susceptibility and gluten exposure to trigger immune-mediated enteropathy. The effect of the degree of gluten-containing grain availability on celiac disease prevalence is unknown. Our objective was to compare country-based gluten availability to celiac prevalence using a systematic literature review. We searched MEDLINE, Embase, Cochrane, and Scopus until May 2021. We included population-based serum screening with confirmatory testing (second serological study or small intestine biopsy) and excluded specific, high-risk, or referral populations. We determined country-specific gluten availability using the United Nations food balance for wheat, barley, and rye. Human leukocyte antigen (HLA) frequencies were obtained from allelefrequencies.net. The primary outcome was association between gluten-containing grain availability and celiac disease prevalence. Generalized linear mixed models method with Poisson's link was used for analysis. We identified 5641 articles and included 120 studies on 427 146 subjects from 41 countries. Celiac disease prevalence was 0-3.1%, median 0.75% (interquartile range 0.35, 1.22). Median wheat supply was 246 g/capita/day (interquartile range 214.8, 360.7). The risk ratio (RR) for wheat availability on celiac disease was 1.002 (95% confidence interval [CI]: 1.0001, 1.004, P = 0.036). A protective association was seen with barley, RR 0.973 (95% CI: 0.956, 0.99, P = 0.003), and rye, RR 0.989 (95% CI: 0.982, 0.997, P = 0.006). The RR for gross domestic product on celiac disease prevalence was 1.009 (95% CI: 1.005, 1.014, P < 0.001). The RR for HLA-DQ2 was 0.982 (95% CI: 0.979, 0.986, P < 0.001), and that for HLA-DQ8 was 0.957 (95% CI: 0.950, 0.964, P < 0.001). In this geo-epidemiologic study, gluten-containing grain availability showed mixed associations with celiac disease prevalence.

Previous SARS-CoV-2 Infection Is Not Associated With Increased Celiac Disease Autoimmunity in Children and Adolescents

INTRODUCTION

Recent reports suggest severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections may increase the risk of celiac disease autoimmunity. This study aims to evaluate potential associations between coronavirus disease 2019 infection and tissue transglutaminase autoantibodies (TGA) immunoglobulin A.

METHODS

From 2020 to 2021, cross-sectional screening for SARS-CoV-2 antibodies and TGA was offered to 4,717 children in Colorado through the Autoimmunity Screening for Kids study. Multivariable logistic regression assessed association between previous SARS-CoV-2 infection and TGA positivity.

RESULTS

Previous SARS-CoV-2 infection was not associated with TGA positivity (odds ratio 1.02, 95% confidence interval 0.63-1.59; P = 0.95).

DISCUSSION

In this large-scale analysis, previous SARS-CoV-2 infection was not associated with celiac disease autoimmunity in Colorado children.

Antibody detection by agglutination-PCR (ADAP) assays for the analysis of tissue transglutaminase autoantibodies in celiac disease

BACKGROUND & AIMS

Tissue transglutaminase autoantibodies (tTGA) are used as diagnostic markers of celiac disease. Different methods have been developed for the detection of tTGA of which enzyme-linked immunosorbent assays (ELISA), radiobinding assays (RBA) and electrochemiluminescence (ECL) assays are the most commonly used. Here we aimed to evaluate a novel antibody determination by agglutination-PCR (ADAP) assay for the detection of tTGA.

METHODS

Included were 126 children with untreated celiac disease (UCD), 64 disease controls (DC), 21 children with potential celiac disease (PCD), and 1501 children from the general population. Tissue TGA were determined using an automated ADAP assay platform and compared with two RBAs for the detection of IgA-tTG and IgG-tTG, respectively.

RESULTS

ADAP detected tTGA in 123/126 (97.6%) UCD children compared with 122/126 (96.8%) using RBA-IgA-tTG and RBA-IgG-tTG (p > 0.9999), respectively. Among DC, ADAP detected 5/64 (7.8%) children with tTGA compared with 4/64 (6.3%) with RBA-IgA-tTG (p > 0.9999) and 8/64 (12.5%) with IgG-tTG (p = 0.5600), respectively. Tissue TGAs were equally detected in children with PCD in both assays. In the general population, 4/1501 (0.3%) were tTGA positive using ADAP compared with 3/1501 (0.2%) for RBA-IgA-tTG and RBA-IgG-tTG (p > 0.9999), respectively. The area under the curves (AUCs) were 0.998 for ADAP, 0.994 for RBA-IgA-tTG, and 0.999 for RBA-IgG-tTG, respectively.

CONCLUSIONS

No difference in specificity and sensitivity of tTGA for the diagnosis of celiac disease was reported between ADAP and RBA. ADAP could be recommended as the first-line screening method of larger populations for celiac disease.

Psychometric validation of the celiac disease-specific quality of life survey (CD-QOL) in adults with celiac disease in the United States

PURPOSE

Celiac disease and its treatment negatively impact quality of life, indicating potential need for measurement of disease-specific quality of life domains to inform interdisciplinary intervention. The Celiac Disease Quality of Life Survey (CD-QOL) has been used in clinical research; however, its factor structure has not been confirmed and psychometric properties have not been evaluated in English-speaking adults in the U.S.

AIMS

(1) Confirm the factor structure of the 20-item English CD-QOL; (2) assess psychometric properties including internal consistency reliability, convergent validity, known groups validity, and incremental validity.

METHODS

453 adults with self-reported Celiac disease (M_age = 40.57; 88% female; 92% White) completed the CD-QOL and validated measures of generic health-related quality of life (SF-36), gluten-free diet adherence (CDAT), anxiety and depression symptoms (PROMIS), and physical symptoms (CSI) as part of the iCureCeliac^® patient-powered research network.

RESULTS

Confirmatory factor analysis found superior fit for a bifactor structure with one general factor and four group factors. Ancillary bifactor analyses suggest the CD-QOL can be considered primarily unidimensional. Total and three subscale scores demonstrated acceptable internal consistency reliability. Convergent and known groups validity were supported. The CD-QOL demonstrated some incremental validity over the SF-36.

CONCLUSION

The English CD-QOL can be used as a measure of disease-specific quality of life among adults with Celiac disease in the U.S. Compared to generic instruments, the CD-QOL appears to better capture specific cognitive and affective aspects of living with Celiac disease. Use of a total score is recommended. Its utility as a screening and outcome measurement tool in clinical settings should be examined.

Precision Medicine in Type 1 Diabetes

Type 1 diabetes is a complex, chronic disease in which the insulin-producing beta cells in the pancreas are sufficiently altered or impaired to result in requirement of exogenous insulin for survival. The development of type 1 diabetes is thought to be an autoimmune process, in which an environmental (unknown) trigger initiates a T cell-mediated immune response in genetically susceptible individuals. The presence of islet autoantibodies in the blood are signs of type 1 diabetes development, and risk of progressing to clinical type 1 diabetes is correlated with the presence of multiple islet autoantibodies. Currently, a "staging" model of type 1 diabetes proposes discrete components consisting of normal blood glucose but at least two islet autoantibodies (Stage 1), abnormal blood glucose with at least two islet autoantibodies (Stage 2), and clinical diagnosis (Stage 3). While these stages may, in fact, not be discrete and vary by individual, the format suggests important applications of precision medicine to diagnosis, prevention, prognosis, treatment and monitoring. In this paper, applications of precision medicine in type 1 diabetes are discussed, with both opportunities and barriers to global implementation highlighted. Several groups have implemented components of precision medicine, yet the integration of the necessary steps to achieve both short- and long-term solutions will need to involve researchers, patients, families, and healthcare providers to fully impact and reduce the burden of type 1 diabetes.

Coeliac Disease Case-Control Study: Has the Time Come to Explore beyond Patients at Risk?

The worldwide prevalence of asymptomatic coeliac disease (CD) is increasing, which is in part due to the routine screening of children with risk factors. Both symptomatic and asymptomatic patients with CD are at risk of long-term complications. The objective of this study was to compare the clinical characteristics of asymptomatic and symptomatic children at the time of CD diagnosis. A case-control study was conducted using data from a cohort of 4838 CD patients recruited from 73 centers across Spain between 2011 and 2017. A total of 468 asymptomatic patients (cases) were selected and matched by age and sex with 468 symptomatic patients (controls). Clinical data, including any reported symptoms, as well as serologic, genetic, and histopathologic data were collected. No significant differences were found between the two groups in most clinical variables, nor in the degree of intestinal lesion. However, the asymptomatic patients were taller (height z-score -0.12 (1.06) vs. -0.45 (1.19), p < 0.001) and were less likely to have anti transglutaminase IgA antibodies ≥ 10 times the upper normal limit (66.2% vs. 758.4%, p = 0.002). Among the 37.1% of asymptomatic patients who were not screened for CD due to the absence of risk factors, only 34% were truly asymptomatic, while the remaining 66% reported non-specific CD-related symptoms. Therefore, expanding CD screening to any child who undergoes a blood test could reduce the burden of care for some children, as many of those considered asymptomatic reported non-specific CD-related symptoms.

Incidence of Pediatric Celiac Disease Varies by Region

INTRODUCTION

The Environmental Determinants of Diabetes in the Young study follows an HLA risk selected birth cohort for celiac disease (CD) development using a uniform protocol. Children under investigation come from 6 different regions within Europe and the United States. Our aim was to identify regional differences in CD autoimmunity and CD cumulative incidence for children born between 2004 and 2010.

METHODS

Children (n = 6,628) with DQ2.5 and/or DQ8.1 were enrolled prospectively from birth in Georgia, Washington, Colorado, Finland, Germany, and Sweden. Children underwent periodic study screening for tissue transglutaminase antibodies and then CD evaluation per clinical care. Population-specific estimates were calculated by weighting the study-specific cumulative incidence with the population-specific haplogenotype frequencies obtained from large stem cell registries from each site.

RESULTS

Individual haplogenotype risks for CD autoimmunity and CD varied by region and affected the cumulative incidence within that region. The CD incidence by age 10 years was highest in Swedish children at 3%. Within the United States, the incidence by age 10 years in Colorado was 2.4%. In the model adjusted for HLA, sex, and family history, Colorado children had a 2.5-fold higher risk of CD compared to Washington. Likewise, Swedish children had a 1.4-fold and 1.8-fold higher risk of CD compared with those in Finland and Germany, respectively.

DISCUSSION

There is high regional variability in cumulative incidence of CD, which suggests differential environmental, genetic, and epigenetic influences even within the United States. The overall high incidence warrants a low threshold for screening and further research on region-specific CD triggers.

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.

Association of Celiac Serology Normalization With the Risk of Hypothyroidism: A Cohort Study

INTRODUCTION

We evaluated whether persistent-positive celiac serology is associated with the risk of hypothyroidism.

METHODS

We extracted a cohort of subjects aged 1-80 years with a positive IgA anti-tissue transglutaminase between January 1, 2008, and December 31, 2012, and a repeat anti-tissue transglutaminase test within 6-36 months from a large population-based electronic medical record database. Based on serology tests, we categorized the pediatric (age &lt;21 years) and adult cohorts into normalized or persistent-positive serology groups. All subjects were followed up for incident diagnosis of hypothyroidism from the last serology date up to December 31, 2017. Hazard ratio (HR) along 95% confidence intervals (CIs) were prepared to evaluate the association of celiac serology group with a diagnosis of hypothyroidism, crude, and adjusted for age, sex, and diagnosis of type 1 diabetes mellitus.

RESULTS

Among the pediatric cohort (n = 2,687), during a median follow-up of 64 months (interquartile range 48-80), 2.3% (16/681) of the persistent-positive serology group and 1.0% (20/2,006) of the normalized serology group developed hypothyroidism (HR 2.07 [95% CI 1.07-4.44], adjHR 1.77 [95% CI 0.91-3.46]). The rate among the pediatric cohort with an established diagnosis of celiac disease was 3.4% (10/486) vs 1.0% (5/481), HR 2.83 (0.96-8.32). In the adult cohort (n = 1,286), 4.5% (20/442) of the persistent-positive group and 3.9% (33/811) of the normalized serology group developed hypothyroidism (HR 1.13 [95% CI 0.65-1.97]).

DISCUSSION

In this retrospective, age-stratified analysis, we report that persistent-positive serology may be associated with the risk of hypothyroidism among the pediatric population. Prospective cohorts are needed to validate our findings.

Anxiety and Depression in Pediatric Patients with Celiac Disease: A Large Cross-Sectional Study

Mental health is a growing concern in pediatric celiac disease (CD). This study utilized the Revised Children's Anxiety and Depression Scale (RCADS) to investigate anxiety and depression symptom rates. Participants were children ages 8 to 17 years (M = 11.7, SD = 2.7; N = 175) with biopsy-proven CD (Median = 1.1 years post-diagnosis, IQR = 0-4) categorized into groups based on the child's age, caregiver or child respondent, presence or absence of comorbidities, and gluten-free diet duration. Self-reported RCADS scores showed 39% of children having clinically significant concerns for anxiety or depression ( P < 0.0001) but only 7% of caregiver-proxy RCADS scores indicated significant concerns for the child's anxiety and 14% for the child's depression. Rates of child-reported anxiety and depression symptoms were significantly higher for those without medical comorbidities than those with ( P = 0.04). Therefore, screening for mental health concerns, particularly anxiety and depression, should be routinely performed in pediatric patients with CD.

Rotavirus vaccination is not associated with incident celiac disease or autoimmune thyroid disease in a national cohort of privately insured children

Rotavirus infection is a potential trigger for autoimmune diseases, and previous reports note associations between rotavirus vaccination and type 1 diabetes. In this report, we examine the association between rotavirus vaccination and autoimmune diseases associated with type 1 diabetes: celiac disease and autoimmune thyroiditis. We conducted a retrospective cohort study using de-identified claims data (Optum Clinformatics^® Data Mart). Eligible infants were born between 2001 and 2018 and continuously enrolled from birth for at least 365 days (n = 2,109,225). Twenty-nine percent (n = 613,295) of infants were born prior to the introduction of rotavirus vaccine in 2006; 32% (n = 684,214) were eligible for the vaccine but were not vaccinated; 9.6% (n = 202,016) received partial vaccination, and 28.9% received full vaccination (n = 609,700). There were 1379 cases of celiac disease and 1000 cases of autoimmune thyroiditis. Children who were born prior to the introduction of rotavirus vaccine in 2006 had lower risk of celiac disease compared to unvaccinated children born after 2006 (hazard ratio [HR] 0.71, 95% confidence interval [CI] 0.59, 0.85). However, children who were partially vaccinated (HR 0.90, 95% CI 0.73, 1.11) or fully vaccinated (HR 1.03, 95% CI 0.88, 1.21) had similar risk to eligible, unvaccinated children. Risk of autoimmune thyroiditis was similar by vaccination status. We conclude that rotavirus vaccination is not associated with increased or decreased risk for celiac disease or autoimmune thyroiditis.

Review article: Becoming and being coeliac-special considerations for childhood, adolescence and beyond

Classically considered a disease of early childhood characterised by malabsorption and failure to thrive, coeliac disease is now recognised to arise in genetically susceptible individuals at any age. Although permissive HLA genotypes are the strongest predictor of coeliac disease, they are not sufficient. Several prospective cohort studies enrolling genetically at-risk infants have investigated the role of potential triggers of coeliac disease autoimmunity, such as timing of gluten introduction, viral infections and dietary patterns. Much less is known about triggers of coeliac disease in adulthood. Better understanding of factors leading to coeliac disease may be helpful in the management of those with potential coeliac disease (elevated serum celiac antibodies without villous atrophy in the small intestine), many of whom initiate a gluten-free diet without demonstration of villous atrophy. There are a range of clinical presentations of celiac disease in childhood and patterns of coeliac serology, including fluctuation and spontaneous reversion on a gluten-containing diet, vary. There is a current debate over best strategies to manage adults and children with potential coeliac disease to avoid over-treatment and under-treatment. Childhood and adolescence carry unique issues pertaining to the diagnosis and management of coeliac disease, and include nutrition and growth, rescreening, repeat biopsy, dietary adherence concerns and transition to adult care. In conclusion, while coeliac disease has similar pathogenesis and general clinical manifestations in paediatric and adult populations, diagnostic and management approaches need to adapt to the developmental stages.

The Prevalence of the Celiac Disease in Patients with Dyspepsia: A Systematic Review and Meta-Analysis

BACKGROUND

Patients with celiac disease (CeD) can commonly present with symptoms of dyspepsia. We conducted a systematic review and meta-analysis of the present literature to assess the prevalence of CeD in patients diagnosed with dyspepsia.

METHODS

We searched MEDLINE and EMBASE databases for the keywords: celiac disease, coeliac disease, anti-gliadin, tissue transglutaminase antibody, anti-endomysial antibody, dyspepsia and functional gastrointestinal disorder. All the studies published from January 1991 till May 2021 were included. Diagnosis of CeD was based on the European Society of Pediatric Gastroenterology, Hepatology and Nutrition guidelines. A random-effects model was used to pool the data.

RESULTS

Twenty-one studies screening 10,275 patients with dyspepsia were included. The pooled seroprevalence of CeD based on a positive anti-tissue transglutaminase antibody and/or anti-endomysial antibody was 4.8% (95% CI [2.8, 6.7%], I2 = 87.7%). The pooled biopsy-confirmed CeD prevalence was 1.5% (95% CI [1.0, 1.9%]; I2 = 59.8%) in these patients. Both seroprevalence (Odds ratio: 1.8; 95% CI [0.8, 4.0%]; I2 = 0%) and prevalence of biopsy-confirmed CeD (Odds ratio: 1.4; 95% CI [0.8, 2.4]; I2 = 0%) were not higher in patients with dyspepsia compared to controls. There was a moderate risk of selection bias and significant heterogeneity in the pooled results.

CONCLUSIONS

The pooled prevalence of CeD in patients with dyspepsia was 1.5% and it was not significantly higher than the general population. These results do not support screening of patients with dyspepsia for CeD.

Recognizing the Emergent and Submerged Iceberg of the Celiac Disease: ITAMA Project-Global Strategy Protocol

Coeliac disease (CD) is frequently underdiagnosed with a consequent heavy burden in terms of morbidity and health care costs. Diagnosis of CD is based on the evaluation of symptoms and anti-transglutaminase antibodies IgA (TGA-IgA) levels, with values above a tenfold increase being the basis of the biopsy-free diagnostic approach suggested by present guidelines. This study showcased the largest screening project for CD carried out to date in school children (n=20,000) aimed at assessing the diagnostic accuracy of minimally invasive finger prick point-of-care tests (POCT) which, combined with conventional celiac serology and the aid of an artificial intelligence-based system, may eliminate the need for intestinal biopsy. Moreover, this study delves deeper into the "coeliac iceberg" in an attempt to identify people with disorders who may benefit from a gluten-free diet, even in the absence of gastrointestinal symptoms, abnormal serology and histology. This was achieved by looking for TGA-IgA mucosal deposits in duodenal biopsy. This large European multidisciplinary health project paves the way to an improved quality of life for patients by reducing the costs for diagnosis due to delayed findings of CD and to offer business opportunities in terms of diagnostic tools and support.

Society for the Study of Celiac Disease position statement on gaps and opportunities in coeliac disease

Progress has been made in understanding coeliac disease, a relatively frequent and underappreciated immune-mediated condition that occurs in genetically predisposed individuals. However, several gaps remain in knowledge related to diagnosis and management. The gluten-free diet, currently the only available management, is not curative or universally effective (some adherent patients have ongoing duodenal injury). Unprecedented numbers of emerging therapies, including some with novel tolerogenic mechanisms, are currently being investigated in clinical trials. In March 2020, the Celiac Disease Foundation and the Society for the Study of Celiac Disease convened a consensus workshop to identify high-yield areas of research that should be prioritized. Workshop participants included leading experts in clinical practice, academia, government and pharmaceutical development, as well as representatives from patient support groups in North America. This Roadmap summarizes key advances in the field of coeliac disease and provides information on important discussions from the consensus approach to address gaps and opportunities related to the pathogenesis, diagnosis and management of coeliac disease. The morbidity of coeliac disease is often underestimated, which has led to an unmet need to improve the management of these patients. Expanded research funding is needed as coeliac disease is a potentially curable disease.

Celiac disease: clinical update

PURPOSE OF REVIEW

This review highlights literature from the past year and explores the impact on current understanding of celiac disease pathogenesis, diagnosis, and management.

RECENT FINDINGS

In contrast to earlier clinical trials, recent data suggests that early gluten introduction may protect against the development of celiac disease. Celiac disease is underdiagnosed, associated with high burden of disease and linked to excess mortality risk, yet, there remains considerable uncertainty regarding the utility of mass screening in asymptomatic individuals. The gut microbiome is increasingly implicated in celiac disease pathogenesis, although the exact mechanism is undefined. Probiotics have been proposed as a disease-modifying option for celiac disease but most studies assessing efficacy are of low-quality. Patients with celiac disease do not appear to be at increased risk of contracting or developing adverse outcomes from COVID-19. Little is known about the pathogenesis of nonceliac gluten sensitivity; however, recent findings suggest an autoimmune basis for the condition.

SUMMARY

Current understanding of celiac disease continues to advance, though significant knowledge gaps remain. Large, rigorous, prospectively designed studies are needed to further characterize celiac disease pathogenesis, management and therapeutic options.

Reliability of the Multiplex CytoBead CeliAK Immunoassay to Assess Anti-tTG IgA for Celiac Disease Screening

Background and Objective: The diagnosis of Celiac Disease (CD) is first based on the positivity for specific serological markers. The CytoBead CeliAK immunoassay simultaneously measures antibodies (IgA) directed to tissue transglutaminase (tTG), endomysium (EMA), and deamidated gliadin (DG), in addition to providing a control for total IgA levels. The aim of this study is to assess the reliability of this multiplex assay to detect anti-tTG IgA positive patients, compared with a conventional single-parameter enzyme-linked immunosorbent assay (ELISA). Methods: Serum samples from 149 pediatric patients were assessed by both CytoBead CeliAK immunoassay and ELISA, in order to evaluate their concordance for the measurement of anti-tTG IgA. Results: The measurement of anti-tTG IgA by CytoBead CeliAK immunoassay basically showed a complete concordance rate with the conventional and single-parameter ELISA, according to the respective cutoff values (3 U/ml and 10 U/ml). Conclusions: Our comparative analysis demonstrates a substantial equivalency between multiplex CytoBead CeliAK assay and the single-parameter conventional ELISA to assess anti-tTG IgA antibody in the context of the screening for CD in children. Importantly, CytoBead CeliAK assay could present some preanalytic, analytic, and economic advantages.

Large-Scale Screening in General Population Children for Celiac Disease with a Multiplex Electrochemiluminescence (ECL) Assay

Background

Autoimmunity Screening for Kids (ASK) study was launched to screen general population children for type 1 diabetes (T1D) and celiac disease (CD).

Methods

A total of 23,319 children from general population were screened. A high throughput multiplex electrochemiluminescence (ECL) assay to screen multiautoantibodies in a single well was applied, parallel with a standard radiobinding assay (RBA). All children with any positive autoantibodies in screening were revisited within one month for confirmation and followed every 6 months.

Results

Among 23,319 children, 2.6% (606/23,319) of children were tested positive for TGA. Multiplex ECL assay detected more TGA (584/23,319) in the initial screening than RBA (490/23,319, p = 0.004) and was able to detect TGA earlier than RBA in a subset of children by 0.8 to 34.8 months. Prevalence of TGA by either ECL or RBA in children with islet autoantibodies was found significantly higher than overall prevalence in general population screened.

Conclusions

A multiplex ECL assay was more sensitive than standard RBA by identifying more TGA positivity and detecting TGA earlier in general population screening. It also provides a high efficient tool with its unique advantage of multiplexing measurements to screen for multiple autoimmune diseases simultaneously in general population.

"ASKing" the Right Questions About Screening for Celiac Disease

Make a distinction between investigating symptoms and screening for disease. Understand the performance characteristics of a test for those with symptoms and for screening those without symptoms, whether at elevated risk or average risk of disease. Positive test results require patient education and follow-up. Importantly, screening should be advantageous to an individual, and disease treatment should be in their interest. The practical application of these principles in relation to population-based Celiac disease screening may be difficult, as a large Colorado study has found.