Fate of five celiac disease-associated antibodies during normal diet in genetically at-risk children observed from birth in a natural history study

Is There a Time and a Place for the Gluten-Free Diet in Potential Celiac Disease?

Potential celiac disease (PCD) is characterized by the absence of villous atrophy on duodenal biopsies (Marsh 0 or 1) despite positive celiac serology and HLA DQ2 or DQ8 heterodimers. Recent epidemiological studies report that PCD represents one fifth of the total CD diagnoses. Compared to patients with CD, the majority of adult patients with PCD show lower rates of nutrient deficiencies and extraintestinal symptoms at diagnosis. Recommending a gluten-free diet (GFD) to PCD patients depends on whether they have symptoms or not. A significant clinical improvement is reported by symptomatic patients, but for asymptomatic PCD, diet implementation is still a matter of debate. Some questions remain to be answered: does PCD serve as an intermediary phase leading to the progression of true CD? Is it reasonable to hypothesize that PCD and active CD represent different manifestations of the same condition? Is there a potential for both underdiagnosis and overdiagnosis of CD in those who may have the condition? Additional research is required to address these inquiries and ascertain the specific subset of people with potential progression to overt CD, as well as to determine the potential advantages of early implementation of a GFD for these individuals. The investigation of risk factors in CD warrants examination of variables such as the timing of diagnosis, the genetic profile, the extent of gluten exposure, and the composition of the microbiome.

Antibody Profile, Gene Expression and Serum Cytokines in At-Risk Infants before the Onset of Celiac Disease

Immunological events that precede the development of villous atrophy in celiac disease (CeD) are still not completely understood. We aimed to explore CeD-associated antibody production (anti-native gliadin (AGA), anti-deamidated gliadin (DGP) and anti-tissue transglutaminase (anti-tTG)) in infants at genetic risk for CeD from the Italian cohorts of the PREVENT-CD and Neocel projects, as well as the relationship between antibody production and systemic inflammation. HLA DQ2 and/or DQ8 infants from families with a CeD case were followed from birth. Out of 220 at-risk children, 182 had not developed CeD by 6 years of age (CTRLs), and 38 developed celiac disease (CeD). The profiles of serum cytokines (INFγ, IL1β, IL2, IL4, IL6, IL10, IL12p70, IL17A and TNFα) and the expression of selected genes (FoxP3, IL10, TGFβ, INFγ, IL4 and IL2) were evaluated in 46 children (20 CeD and 26 CTRLs). Among the 182 healthy CTRLs, 28 (15.3%) produced high levels of AGA-IgA (AGA+CTRLs), and none developed anti-tTG-IgA or DGP-IgA, compared to 2/38 (5.3%) CeD infants (Chi Sq. 5.97, p = 0.0014). AGAs appeared earlier in CTRLs than in those who developed CeD (19 vs. 28 months). Additionally, the production of AGAs in CeD overlapped with the production of DGP and anti-tTG. In addition, gene expression as well as serum cytokine levels discriminated children who developed CeD from CTRLs. In conclusion, these findings suggest that the early and isolated production of AGA-IgA antibodies is a CeD-tolerogenic marker and that changes in gene expression and cytokine patterns precede the appearance of anti-tTG antibodies.

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.

Antitissue transglutaminase antibodies' normalization after starting a gluten-free diet in a large population of celiac children-a real-life experience

INTRODUCTION

Few data are available regarding the trend of IgA anti-transglutaminase antibodies (TGA-IgA) in children with celiac disease (CD) on a gluten-free diet (GFD). Our aim is to examine the normalization time of CD serology in a large pediatric population, and its predictors.

MATERIAL AND METHODS

We retrospectively evaluated the normalization time of TGA-IgA and its predictive factors (age, sex, ethnicity, symptoms, associated diabetes/thyroiditis, Marsh stage, TGA-IgA and endomysial antibody levels at diagnosis, diet adherence), in 1024 children diagnosed from 2000 to 2019 in three pediatric Italian centers, on a GFD.

RESULTS

TGA-IgA remission was reached in 67,3%, 80,7%, 89,8% and 94,9% after 12, 18, 24 and 36 months from starting a GFD, respectively (median time = 9 months). TGA-IgA >10´upper limit of normal at diagnosis (HR = 0.56), age 7-12 years old (HR = 0.83), poor compliance to diet (HR = 0.69), female sex (HR = 0.82), non-Caucasian ethnicity (HR = 0.75), and comorbidities (HR = 0.72) were independent factors significantly associated with longer time to normalization.

CONCLUSIONS

Our population is the largest in the literature, with the majority of patients normalizing CD serology within 24 months from starting a GFD. We suggest a special attention to patients with comorbidities, language barriers or age 7-12 years for a proper management and follow-up.

Changes in Non-Deamidated versus Deamidated Epitope Targeting and Disease Prediction during the Antibody Response to Gliadin and Transglutaminase of Infants at Risk for Celiac Disease

Celiac disease (CeD) is a conditional autoimmune disorder with T cell-mediated immune response to gluten coupled with antibody production to gliadin and the self-protein tissue transglutaminase (TG2). TG2 contributes to the CeD pathomechanism by deamidating gliadin, thereby generating more immunogenic peptides. Anti-gliadin antibodies may appear before the autoantibody production. The scope of this study was to dissect these early antibody responses by investigating serum samples collected during the PreventCD prospective double-blind study, where infants with high CeD risk were randomized to 200 mg daily gluten intake or placebo from 4 to 6 months of age, followed by frequent blood testing on regular gluten consumption in both groups. After primary gluten intake, children with or without later CeD produced IgA and IgG antibodies which preferentially recognized non-deamidated gliadin peptides. At CeD development with anti-TG2 seroconversion, there was a significant increase in the antibody reaction toward deamidated gliadin peptides (DGP), with maturation in the binding strength for the PEQPFP gamma-gliadin core peptide. The earliest produced autoantibodies targeted TG2’s celiac epitope 2. Our results reveal a qualitative change in the gliadin-directed humoral immune response at the time when anti-TG2 antibodies appear, but anti-DGP antibodies in the absence of anti-TG2 antibodies are not disease-predictive.

Celiac disease can be predicted by high levels of tissue transglutaminase antibodies in children and adolescents with type 1 diabetes

OBJECTIVES

Children with type 1 diabetes (T1D) are not included in guidelines regarding diagnosis criteria for celiac disease (CD) without a diagnostic biopsy, due to lack of data. We explored whether tissue transglutaminase antibodies (anti-tTG) that were ≥ 10 times the upper limit of normal (10× ULN) predicted CD in T1D.

METHODS

Data from the Swedish prospective Better Diabetes Diagnosis study was used, and 2035 children and adolescents with T1D diagnosed between 2005-2010 were included. Of these, 32 had been diagnosed with CD before T1D. The children without CD were repeatedly screened for CD using anti-tTG antibodies of immunoglobulin type A. In addition, their human leukocyte antigen (HLA) were genotyped. All children with positive anti-tTG were advised to undergo biopsy. Biopsies were performed on 119 children and graded using the Marsh-Oberhüber classification.

RESULTS

All of the 60 children with anti-tTG ≥10x ULN had CD verified by biopsies. The degree of mucosal damage correlated with anti-tTG levels. Among 2003 screened children, 6.9% had positive anti-tTG and 5.6% were confirmed CD. The overall CD prevalence, when including the 32 children with CD before T1D, was 7.0% (145/2035). All but one of the children diagnosed with CD had HLA-DQ2 and/or DQ8.

CONCLUSIONS

As all screened children and adolescents with T1D with tissue transglutaminase antibodies above 10 times the positive value 10x ULN had CD, we propose that the guidelines for diagnosing CD in screened children, when biopsies can be omitted, should also apply to children and adolescents with T1D as a noninvasive method.

Prevalence and diagnostic outcomes of children with duodenal lesions and negative celiac serology

BACKGROUND

Celiac disease diagnostics begin by measuring autoantibodies, which may fail to identify seronegative patients. Duodenal lesion in the absence of antibodies is scarcely studied, especially in children.

AIMS

To investigate the prevalence and diagnostic outcomes of children with seronegative duodenal lesion in two countries with different disease profiles.

METHODS

Medical data, including the results of histology and transglutaminase (tTGab) and endomysium (EmA) antibody measurements were collected from 1172 Finnish and 264 Romanian children with systematic duodenal sampling. Database of 509 Finnish children with celiac disease was examined to identify earlier seronegative patients.

RESULTS

Celiac disease was diagnosed in 307 Finnish and 83 Romanian children in the endoscopy cohorts. No seronegative patients were found among 899 celiac disease patients, although some were only tTGab or EmA positive. Non-celiac duodenal lesion was detected in eight Finnish and 32 Romanian children, their most common diagnoses being inflammatory bowel disease and infections, respectively. Six children with morphological lesion received no diagnosis. None of them developed celiac disease during a follow-up of 3-11 years.

CONCLUSION

Pediatric seronegative celiac disease is exceptional in the era of modern autoantibodies. Other reasons for duodenal lesion should therefore be sought, bearing in mind possible differences across countries.

Efficacy Study of Anti-Endomysium Antibodies for Celiac Disease Diagnosis: A Retrospective Study in a Spanish Pediatric Population

The aim of this study was to assess the efficacy of anti-endomysium antibodies (EMA) as a serological marker for celiac disease (CD) diagnosis in a pediatric population. A retrospective study of pediatric patients who underwent a CD serological markers study: EMA and anti-tissue transglutaminase antibodies (anti-TG2). Clinical symptomatology, degree of histological lesion, human leukocyte antigen (HLA) haplotype compatible with CD (HLA DQ2 and/or DQ8), and final diagnosis were taken into account. We included 445 patients who were classified in two groups according to the final diagnosis. Group 1: 232 children with CD, 91.4% of whom exhibited small intestinal villous atrophy, 228 being EMA-positive and four EMA-negative. Group 2: 213 children with a non-CD diagnosis, 212 EMA negative and one EMA positive. Both antibodies, EMA and anti-TG2, reached similar sensitivities, 98% and 99% respectively, while EMA had a higher specificity (99%) than anti-TG2 (93%). By using both markers combined, compared to using anti-TG2 alone, 5.7% of patients are better diagnosed. However, when we compare the efficacy of EMA and anti-TG2 in asymptomatic and symptomatic patients, the sensitivity of EMA is 98% irrespective of symptoms, thus higher than for anti-TG2 ≥10 × upper limit of normal (ULN) (respectively 77% and 84%). Our results support the use of EMA to increase CD diagnostic accuracy in a non-biopsy approach, especially in asymptomatic children.

Prevalence of Celiac Disease in a Long-term Study of a Spanish At-genetic-risk Cohort From the General Population

OBJECTIVES

To perform long-term celiac disease (CD) screening in an HLA-DQ2 (+) cohort from the general population and to assess the influence of risk genotypes on its development.

METHODS

In 2004, an HLA-DQ2 (+) cohort was selected. After the first CD screening at age 2 to 3 years, we performed a follow-up screening 8 to 10 years later. Antitransglutaminase 2 antibodies were determined using a rapid test kit. Results were confirmed by serum IgA antitransglutaminase 2 and IgA endomysial antibody determination. CD diagnosis was carried out by intestinal biopsies. Four HLA-DQ2 genotypic groups were used: G1: DQ2.5/DQ2.5 (G1A) or DQ2.5/ DQ2.2 (G1B); G2: DQ2.2/DQ7.5 (DQ2.5 trans); G3: DQ2.5/ X; G4: DQ2.2/X.

RESULTS

CD prevalence after 10 years of follow-up was 5.8% (95% confidence interval 3.8-8.7). One of every 3 HLA-DQ2(+) children carried at least 1 haplotype DQ2.2 or DQ7. The homozygous genotype DQ2.5/DQ2.5 and the HLA-DQ2.5 trans genotype increased CD risk 4- and 3-fold, respectively. The homozygous genotype DQ2.5/ DQ2.2 did not increase the CD risk. Children carrying G1 or G2 genotypes were diagnosed with CD earlier and more frequently during the follow-up compare with those carrying G3 or G4 genotypes. Approximately 81% of children with spontaneous antibody negativization after the first screening maintained negative antibodies.

CONCLUSIONS

A repeated screening of at-risk children during their follow-up allowed us to diagnose new CD cases. In our cohort, HLA- DQ2.5 trans genotype conferred a higher risk in the development of CD than HLA- DQ2.5/DQ2.2. The majority of children with potential CD and CD autoimmunity at 10 years of age remained healthy.

Long-Term Outcome of Potential Celiac Disease in Genetically at-Risk Children: The Prospective CELIPREV Cohort Study

BACKGROUND

The long-term outcome of potential celiac disease (CD) is still a debated issue. We aimed to evaluate the progression of potential CD versus overt CD after 10-years of follow-up in a cohort of children genetically predisposed to CD.

METHODS

The CELIPREV study is prospectively following from birth 553 children with CD-predisposing HLA genes. Children with a diagnosis of potential CD continued to receive a normal diet and repeated the serological screening for CD every year. An intestinal biopsy was taken in presence of persistent positive serology.

RESULTS

Overall, 26 (4.7%) children received a diagnosis of potential CD (50% females, median age 24 months). All children were symptom-free. Twenty-three children continued a gluten-containing diet; at 10 years from the first biopsy, three children developed overt CD (13%), 19 (83%) became antibodies negative at 1 year from the first biopsy and remained negative up to 10 years of follow-up and one subject (4%) had fluctuating antibody course with transiently negative values and persistently negative biopsy.

CONCLUSIONS

In children genetically predisposed to CD with a diagnosis of potential CD the risk of progression to overt CD while on a gluten-containing diet is very low in the long-term.

Natural history and clinical detection of undiagnosed coeliac disease in a North American community

BACKGROUND

Coeliac disease is a substantially underdiagnosed disorder, with clinical testing currently guided by case finding.

AIM

To determine the presence of indications for diagnostic testing and frequency of clinical testing in undiagnosed coeliac disease.

METHODS

This was a case-control study of adults without prior diagnosis of coeliac disease. Undiagnosed cases were identified through sequential serology, and unaffected age- and gender-matched controls were selected. Medical records were systematically reviewed for indications for and evidence of clinical testing.

RESULTS

Of 47 557 adults, 408 cases of undiagnosed coeliac disease were identified. 408 serology negative matched controls were selected. Eight-matched pairs were excluded, leading to 800 included individuals (61% female; median age 44.2 years). The odds of any indication for clinical testing were similar among undiagnosed coeliac disease and controls (odds ratio (OR) 1.18; 95% CI: 0.85-1.63, P = 0.32). Most individual indications were not associated with serologic status. Exceptions to this include hypothyroidism, which was more likely in cases of undiagnosed coeliac disease, and dyspepsia and chronic diarrhoea, which were less likely. Cases of undiagnosed coeliac disease were more likely to develop osteoporosis (P = 0.005), dermatitis herpetiformis (P = 0.006), chronic fatigue (P = 0.033), thyroiditis (P = 0.003), autoimmune diseases (P = 0.008), and have a family member diagnosed with coeliac disease (P = 0.001).

CONCLUSION

This study strongly suggests that current case finding is not effective in detecting undiagnosed coeliac disease. Individuals with undiagnosed coeliac disease were more likely than controls to develop indications for testing overtime. A more effective method for detection of coeliac disease is needed.

Avoidance of Cow's Milk-Based Formula for At-Risk Infants Does Not Reduce Development of Celiac Disease: A Randomized Controlled Trial

BACKGROUND & AIMS

Feeding during the first months of life might affect risk for celiac disease. Individuals with celiac disease or type 1 diabetes have been reported to have high titers of antibodies against cow's milk proteins. Avoidance of cow's milk-based formula for infants with genetic susceptibility for type 1 diabetes reduced the cumulative incidence of diabetes-associated autoantibodies. We performed a randomized controlled trial in the same population to study whether weaning to an extensively hydrolyzed formula reduced the risk of celiac disease autoimmunity or celiac disease.

METHODS

We performed a double-blind controlled trial of 230 infants with HLA-defined predisposition to type 1 diabetes and at least 1 family member with type 1 diabetes. The infants were randomly assigned to groups fed a casein hydrolysate formula (n = 113) or a conventional formula (control, n = 117) whenever breast milk was not available during the first 6-8 months of life. Serum samples were collected over a median time period of 10 years and analyzed for antibodies to tissue transglutaminase (anti-TG2A) using a radiobinding assay, to endomysium using an immunofluorescence assay, and antibodies to a deamidated gliadine peptide using an immunofluorometry assay. Duodenal biopsies were collected if levels of anti-TG2A exceeded 20 relative units. Cow's milk antibodies were measured during the first 2 years of life.

RESULTS

Of the 189 participants analyzed for anti-TG2A, 25 (13.2%) tested positive. Of the 230 study participants observed, 10 (4.3%) were diagnosed with celiac disease. We did not find any significant differences at the cumulative incidence of anti-TG2A positivity (hazard ratio, 1.14; 95% confidence interval, 0.51-2.54) or celiac disease (hazard ratio, 4.13; 95% confidence interval, 0.81-21.02) between the casein hydrolysate and cow's milk groups. Children who developed celiac disease had increased titers of cow's milk antibodies before the appearance of anti-TG2A or celiac disease.

CONCLUSIONS

In a randomized controlled trial of 230 infants with genetic risk factors for celiac disease, we did not find evidence that weaning to a diet of extensively hydrolyzed formula compared with cow's milk-based formula would decrease the risk for celiac disease later in life. Increased titers of cow's milk antibody before anti-TG2A and celiac disease indicates that subjects with celiac disease might have increased intestinal permeability in early life. ClinicalTrials.gov Number: NCT00570102.

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.

Coeliac disease in infants: antibodies to deamidated gliadin peptide come first!

Background

The onset of coeliac disease (CD) in the first year of life is uncommon and the diagnosis can be challenging due to the suboptimal sensitivity of tissue transglutaminase antibodies (tTG) at this age and the many other possible causes of malabsorption in infants. Antibodies to deamidated gliadin peptides (anti-DGPs), especially IgG, may appear earlier than IgA anti-tTG in very young children with CD.

Case presentation

We report here on an 8-month-old child who was evaluated for failure to thrive, constipation and developmental delay. The symptoms started following gluten introduction in the diet. Laboratory tests showed high fecal elastase concentration, normal serum IgA levels with positive IgG and IgA anti-DGPs, whereas anti-tTG were not detected. The duodenal biopsy revealed a complete villous atrophy (Marsh-Oberhuber 3C). The culture of biopsy fragments in the presence of gliadin peptides did not stimulate the production of IgA anti-endomysial antibodies. Genetic testing proved the child was positive for HLA-DQ2 (DQA1*05; DQB1*02) and HLA-DQ8 (DQA1*03, DQB1*0302). Having initiated the gluten-free diet, the symptoms disappeared and the infant experienced rapid catch-up growth with normalization of psychomotor development.

Conclusions

This case report highlights the utility of anti-DGPs for screening infants with suspected CD. The pattern with positivity for IgG and IgA anti-DGPs only is rare in IgA-competent children with biopsy-proven CD. It could be explained in infancy as immaturity of the adaptive immune system.

Antitissue Transglutaminase Normalization Postdiagnosis in Children With Celiac Disease

OBJECTIVES

Limited pediatric data exist examining the trend and predictors of antitissue transglutaminase (atTG) normalization over time in children with celiac disease (CD). We aimed to evaluate time to normalization of atTG in children after CD diagnosis, and to assess for independent predictors affecting this duration.

METHODS

A retrospective chart review was completed in pediatric patients with CD diagnosed from 2007 to 2014 at the Stollery Children's Hospital Celiac Clinic (Edmonton, Alberta, Canada). The clinical predictors assessed for impact on time to atTG normalization were initial atTG, Marsh score at diagnosis, gluten-free diet compliance (GFDC), age at diagnosis, sex, ethnicity, medical comorbidities, and family history of CD. Kaplan-Meier survival analysis was completed to assess time to atTG normalization, and Cox regression to assess for independent predictors of this time.

RESULTS

A total of 487 patients met inclusion criteria. Approximately 80.5% of patients normalized atTG levels. Median normalization time was 407 days for all patients (95% confidence interval [CI: 361-453]), and 364 days for gluten-free diet compliant patients (95% CI [335-393]). Type 1 diabetes mellitus (T1DM) patients took significantly longer to normalize at 1204 days (95% CI [199-2209], P < 0.001). Cox regression demonstrated T1DM (hazard ratio = 0.36 [0.24-0.55], P < 0.001) and higher baseline atTG (hazard ratio = 0.52 [0.43-0.63], P < 0.001) were significant predictors of longer atTG normalization time. GFDC was a significant predictor of earlier normalization (OR = 13.91 [7.86-24.62], P < 0.001).

CONCLUSIONS

GFDC and lower atTG at diagnosis are predictors of earlier normalization. Patients with T1DM are less likely to normalize atTG levels, with longer normalization time. Additional research and education for higher-risk populations are needed.

Reovirus infection triggers inflammatory responses to dietary antigens and development of celiac disease

Viral infections have been proposed to elicit pathological processes leading to the initiation of T helper 1 (TH1) immunity against dietary gluten and celiac disease (CeD). To test this hypothesis and gain insights into mechanisms underlying virus-induced loss of tolerance to dietary antigens, we developed a viral infection model that makes use of two reovirus strains that infect the intestine but differ in their immunopathological outcomes. Reovirus is an avirulent pathogen that elicits protective immunity, but we discovered that it can nonetheless disrupt intestinal immune homeostasis at inductive and effector sites of oral tolerance by suppressing peripheral regulatory T cell (pTreg) conversion and promoting TH1 immunity to dietary antigen. Initiation of TH1 immunity to dietary antigen was dependent on interferon regulatory factor 1 and dissociated from suppression of pTreg conversion, which was mediated by type-1 interferon. Last, our study in humans supports a role for infection with reovirus, a seemingly innocuous virus, in triggering the development of CeD.

Anemia and Iron Deficiency in Children With Potential Celiac Disease

OBJECTIVES

Active screening for celiac disease frequently detects seropositive children with normal villous morphology (potential celiac disease). It remains unclear whether these subjects should be treated. We here investigated the prevalence of anemia and iron deficiency in children with potential and mucosal atrophy celiac disease.

METHODS

The prospective study involved 19 children with potential disease, 67 with partial or subtotal villous atrophy (P/SVA), and 16 with total villous atrophy (TVA). Twenty-three healthy children comprised the control group. The groups were compared for various clinical, histological, and laboratory parameters and hepcidin.

RESULTS

The prevalence of abnormal parameters was as follows (controls, potential celiac disease, P/SVA, and TVA, respectively): anemia 0%, 15%, 22%, and 63%; low iron 5%, 0%, 14%, and 50%; increased transferrin receptor 1 5%, 16%, 20%, and 47%; low ferritin 0%, 21%, 35%, and 87%; and low transferrin saturation 10%, 11%, 41%, and 71%. One subject had low folate and none had low vitamin B12. The median values for hemoglobin, total iron, ferritin, and transferrin saturation were significantly lower and transferrin receptor 1 values higher in TVA group compared with other groups. After a median of 7 months on a gluten-free diet hemoglobin, total iron, ferritin, and albumin in children with P/SVA exceeded the baseline values in the potential celiac disease group.

CONCLUSIONS

The development of anemia and iron deficiency in celiac disease is a continuum and may already be present in children with normal villous morphology, advocating an early diagnosis and possible dietary treatment of these patients.

Development of gliadin-specific immune responses in children with HLA-associated genetic risk for celiac disease

OBJECTIVE

The development of gliadin-specific antibody and T-cell responses were longitudinally monitored in young children with genetic risk for celiac disease (CD).

MATERIAL AND METHODS

291 newborn children positive for HLA-DQB1*02 and -DQA1*05 alleles were followed until 3-4 years of age by screening for tissue transglutaminase autoantibodies (tTGA) by using a commercial ELISA-based kit and antibodies to deamidated gliadin peptide (anti-DGP) by an immunofluorometric assay. Eighty-five of the children were also followed for peripheral blood gliadin-specific CD4(+) T-cell responses by using a carboxyfluorescein diacetate succinimidyl ester-based in vitro proliferation assay.

RESULTS

The cumulative incidence of tTGA seropositivity during the follow-up was 6.5%. CD was diagnosed in nine of the tTGA-positive children (3.1%) by duodenal biopsy at a median 3.5 years of age. All of the children with confirmed CD were both IgA and IgG anti-DGP positive at the time of tTGA seroconversion and in over half of the cases IgG anti-DGP positivity even preceded tTGA seroconversion. Peripheral blood T-cell responses to deamidated and native gliadin were detected in 40.5% and 22.2% of the children at the age of 9 months and these frequencies decreased during the follow-up to the levels of 22.2% and 8.9%, respectively.

CONCLUSIONS

Anti-DGP antibodies may precede tTGA seroconversion and thus frequent monitoring of both tTGA and anti-DGP antibodies may allow earlier detection of CD in genetically susceptible children. Peripheral blood gliadin-specific T-cell responses are relatively common in HLA-DQ2-positive children and are not directly associated with the development of CD.

Current evidence on whether perinatal risk factors influence coeliac disease is circumstantial

Coeliac disease is triggered by an interplay of environmental and genetic factors and is one of the most prevalent autoimmune diseases in children, occurring in about 1% of Europeans. Over the last few decades, there has been a growing interest in the role of the perinatal environment in coeliac disease and this review discusses the growing body of literature on coeliac disease and perinatal risk factors.

CONCLUSION

There is still only circumstantial evidence that the perinatal environment influences coeliac disease development. Large-scale cohort studies and emerging scientific concepts, such as epigenetics, may help us establish the role of these environmental factors.

Celiac disease and non-celiac gluten sensitivity

Celiac disease is a multisystem immune based disorder that is triggered by the ingestion of gluten in genetically susceptible individuals. The prevalence of celiac disease has risen in recent decades and is currently about 1% in most Western populations. The reason for this rise is unknown, although environmental factors related to the hygiene hypothesis are suspected. The pathophysiology of celiac disease involves both the innate and adaptive immune response to dietary gluten. Clinical features are diverse and include gastrointestinal symptoms, metabolic bone disease, infertility, and many other manifestations. Although a gluten-free diet is effective in most patients, this diet can be burdensome and can limit quality of life; consequently, non-dietary therapies are at various stages of development. This review also covers non-celiac gluten sensitivity. The pathophysiology of this clinical phenotype is poorly understood, but it is a cause of increasing interest in gluten-free diets in the general population.

Antibodies to deamidated gliadin peptide in diagnosis of celiac disease in children

OBJECTIVES

Determination of antibodies to synthetic deamidated gliadin peptides (anti-DGPs) may work as an alternative or complement the commonly used test for tissue transglutaminase antibodies (TGA) in the diagnosis of celiac disease (CD). We analyzed the performance of a time-resolved immunofluorometric anti-DGP assay (TR-IFMA) in the diagnosis of CD in children and also retrospectively analyzed the appearance of anti-DGP antibodies before TGA seroconversion.

METHODS

The study included 92 children with biopsy-confirmed CD. Serum samples were taken at the time or just before the clinical diagnosis. The control group comprised 82 TGA-negative children who were positive for human leucocyte antigen-DQ2 or -DQ8.

RESULTS

Based on receiver operating characteristic curves, the optimal cutoff value for immunoglobulin (Ig) A anti-DGP positivity was 153 arbitrary units (AUs) with a sensitivity of 92.4% and specificity of 97.6% and that for IgG anti-DGP 119 AU, with a sensitivity of 97.8% and specificity of 97.6%. All 92 children with CD were either IgA or IgG anti-DGP positive at the time of diagnosis. Sera from 48 children with CD were also analyzed retrospectively before the diagnosis. Anti-DGP antibodies preceded TGA positivity in 35 of the 48 children with CD and appeared a median of 1 year earlier.

CONCLUSIONS

The TR-IFMA assay for detecting anti-DGP antibodies shows high sensitivity and specificity for the diagnosis of CD in children. In a majority of our study population, anti-DGP seropositivity preceded TGA positivity, indicating that earlier detection of CD may be possible by monitoring anti-DGP antibodies frequently in genetically susceptible children.

Assessing of Celiac Disease and Nonceliac Gluten Sensitivity

The publication of papers on the topic of gluten related disorders has substantially increased over the last few years. This has motivated healthcare professionals to pay attention not only to celiac disease and wheat allergy but also to a condition termed nonceliac gluten sensitivity (NCGS). Until now this condition has been diagnosed clinically on the basis of exclusion criteria and clinical response to gluten withdrawal. In addition, recent research in this field has shown that other food components distinct from gluten are implicated in NCGS cases, thereby changing our general understanding of NCGS diagnosis in either individuals on gluten containing diets or those already following a gluten-free diet with no proper diagnostic work-up of celiac disease. With this in mind, the assessment of NCGS will require extensive knowledge of celiac disease manifestations and the laboratory tests commonly performed during diagnosis of celiac disease.

The diagnosis and treatment of celiac disease

BACKGROUND

Celiac disease is an inflammatory disease of, the small intestine with a prevalence of roughly 0.5%-1%. Its symptoms arise in response to gluten consumption by genetically predisposed persons (HLA-DQ2/8). The autoantigen tissue transglutaminase (TG2) plays an important role in the pathogenesis of celiac disease.

METHOD

Selective review of pertinent literature, including guidelines from Germany and abroad.

RESULTS

Celiac disease can present at any age with gastrointestinal or extraintestinal manifestations (e.g., malabsorption or Duhring's dermatitis herpetiformis); it can also be found in association with other (auto-)immune diseases, such as type 1 diabetes. Most cases are oligosymptomatic. The wide differential diagnosis includes food intolerances, intestinal infections, and irritable bowel syndrome, among other conditions. The definitive diagnosis requires the demonstration of celiac disease-specific autoantibody to TG2 (endomysium), which is over 90% sensitive and far over 90% specific, and the characteristic histologic lesions of the small-bowel mucosa and remission on a gluten-free diet.

CONCLUSION

An understanding of celiac disease ought to inform everyday clinical practice in all medical disciplines, because this is a common condition with diverse manifestations that can be effectively diagnosed and easily treated for the prevention of both acute and long-term complications. Patients should follow a strictly gluten-free diet for life.

Diagnosing coeliac disease and the potential for serological markers

The diagnosis of coeliac disease has advanced in the past decade owing to increased clinical awareness and improved tests. Coeliac disease is now regarded as a common disease presenting at any age with a broad spectrum of symptoms. Previous guidelines on diagnosis relied on the histological analysis of duodenal biopsy samples. However, contemporary antibody analysis is a diagnostic tool with a comparatively high accuracy that has reduced reliance on performing biopsies. Furthermore, determination of HLA-based genetic susceptibility to coeliac disease has become routine. European and North American guidelines utilize symptoms, coeliac antibodies (primarily tissue transglutaminase 2 IgA and endomysial IgA antibodies), HLA determination and histological analysis of biopsy tissue for diagnosis. Some guidelines conclude that the diagnostic accuracy of tissue transglutaminase 2 IgA antibodies is sufficient to omit duodenal biopsies in selected children with very high antibody levels, in the presence of clear symptom response as well as a positive endomysial antibody test and confirmation of genetic susceptibility. This Review discusses if such a strategy is appropriate for children and adults in all populations. The performance characteristics of antibody tests (particularly of the tissue transglutaminase 2 IgA test) including quality control and characterisation of the population in whom testing is performed are also discussed.

Autoantibodies and CD: past and future of celiac antibody testing

Celiac disease (CD) is triggered by the consumption of gluten-containing cereals to which patients mount a T-lymphocyte and antibody response in both immunoglobulin A and immunoglobulin G classes coupled with autoantibody production against self-proteins, predominantly type-2 (tissue) transglutaminase (TG2). TG2 autoantibodies are biologically active and bind to their target protein in the patients' tissues, including the gut and extraintestinal tissues. This peculiar systemic anti-TG2 reaction is dependent on the presence of dietary gluten and stops after its elimination. As both anti-TG2 and anti-gliadin antibodies are activity markers, their detection is valuable for the disease recognition and therapy monitoring. High concentrations of serum anti-TG2 antibody positivity supported by highly specific positivity for endomysial antibodies became the critical component of celiac disease diagnosis, although serum antibodies as indirect markers have limitations and are not able to replace histology analysis in all cases. Studies focusing on tissue-bound antibodies may further improve our understanding of their role.

Issues associated with the emergence of coeliac disease in the Asia–Pacific region: a working party report of the World Gastroenterology Organization and the Asian Pacific Association of Gastroenterology

BACKGROUND AND AIM

Once thought to be uncommon in Asia, coeliac disease (CD) is now being increasingly recognized in Asia–Pacific region. In many Asian nations, CD is still considered to be either nonexistent or very rare. In recognition of such heterogeneity of knowledge and awareness, the World Gastroenterology Organization and the Asian Pacific Association of Gastroenterology commissioned a working party to address the key issues in emergence of CD in Asia.

METHODS

A working group consisting of members from Asia–Pacific region, Europe, North America, and South America reviewed relevant existing literature with focus on those issues specific to Asia–Pacific region both in terms of what exists and what needs to be done.

RESULTS

The working group identified the gaps in epidemiology, diagnosis, and management of CD in Asian–Pacific region and recommended the following: to establish prevalence of CD across region, increase in awareness about CD among physicians and patients, and recognition of atypical manifestations of CD. The challenges such as variability in performance of serological tests, lack of population-specific cut-offs values for a positive test, need for expert dietitians for proper counseling and supervision of patients, need for gluten-free infrastructure in food supply and creation of patient advocacy organizations were also emphasized.

CONCLUSIONS

Although absolute number of patients with CD at present is not very large, this number is expected to increase over the next few years or decades. It is thus appropriate that medical community across the Asia–Pacific region define extent of problem and get prepared to handle impending epidemic of CD.

Accurate and robust genomic prediction of celiac disease using statistical learning

Practical application of genomic-based risk stratification to clinical diagnosis is appealing yet performance varies widely depending on the disease and genomic risk score (GRS) method. Celiac disease (CD), a common immune-mediated illness, is strongly genetically determined and requires specific HLA haplotypes. HLA testing can exclude diagnosis but has low specificity, providing little information suitable for clinical risk stratification. Using six European cohorts, we provide a proof-of-concept that statistical learning approaches which simultaneously model all SNPs can generate robust and highly accurate predictive models of CD based on genome-wide SNP profiles. The high predictive capacity replicated both in cross-validation within each cohort (AUC of 0.87–0.89) and in independent replication across cohorts (AUC of 0.86–0.9), despite differences in ethnicity. The models explained 30–35% of disease variance and up to ∼43% of heritability. The GRS's utility was assessed in different clinically relevant settings. Comparable to HLA typing, the GRS can be used to identify individuals without CD with ≥99.6% negative predictive value however, unlike HLA typing, fine-scale stratification of individuals into categories of higher-risk for CD can identify those that would benefit from more invasive and costly definitive testing. The GRS is flexible and its performance can be adapted to the clinical situation by adjusting the threshold cut-off. Despite explaining a minority of disease heritability, our findings indicate a genomic risk score provides clinically relevant information to improve upon current diagnostic pathways for CD and support further studies evaluating the clinical utility of this approach in CD and other complex diseases.

Celiac disease (CD) is a common immune-mediated illness, affecting approximately 1% of the population in Western countries but the diagnostic process remains sub-optimal. The development of CD is strongly dependent on specific human leukocyte antigen (HLA) genes, and HLA testing to identify CD susceptibility is now commonly undertaken in clinical practice. The clinical utility of HLA typing is to exclude CD when the CD susceptibility HLA types are absent, but notably, most people who possess HLA types imparting susceptibility for CD never develop CD. Therefore, while genetic testing in CD can overcome several limitations of the current diagnostic tools, the utility of HLA typing to identify those individuals at increased-risk of CD is limited. Using large datasets assaying single nucleotide polymorphisms (SNPs), we have developed genomic risk scores (GRS) based on multiple SNPs that can more accurately predict CD risk across several populations in “real world” clinical settings. The GRS can generate predictions that optimize CD risk stratification and diagnosis, potentially reducing the number of unnecessary follow-up investigations. The medical and economic impact of improving CD diagnosis is likely to be significant, and our findings support further studies into the role of personalized GRS's for other strongly heritable human diseases.

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.

Diagnostic utility of modified gliadin peptide antibody assays in New Zealand children

OBJECTIVE

The aim of the present study was to evaluate a panel of different antibody assays, including second-generation antigliadin kits, in a local paediatric population thought to be at risk for coeliac disease (CD).

METHODS

Seventy-nine children, who tested positive for immunoglobulin A (IgA) antibodies to tissue transglutaminase (TG), underwent duodenal biopsy. At endoscopy, serum was collected from all of the patients, and 9 different coeliac antibody assays were performed, both as isolated assays and in combination. These included immunoglobulin A (IgA) anti-tissue transglutaminase (TGA), and IgA plus IgG anti-deamidated gliadin peptide (DGPAG). A diagnosis of CD was made if the biopsies showed Marsh grade 3 lesions.

RESULTS

Twenty-four of 79 children had CD confirmed histologically. Only 39 of 79 were positive for Inova TGA, and 35 of 79 were positive for Inova DGPAG. Twenty-four of 39 who were TGA positive and 24 of 35 who were DGPAG positive had confirmed CD on biopsy. There was good correlation between TGA and DGPAG-positive predictive values. None of the modified gliadin tests produced false-negative results, and neither did the TGA.

CONCLUSIONS

The Inova DGPAG and TGA assays have similar use in predicting CD in a selected paediatric population; however, in children who are positive for TGA when screened for CD, more than half have negative TGA serology when repeat testing is done at the time of biopsy. Those with persistent TGA positivity have only a 61.5% probability of having histologic CD, compared with 68.6% of those children positive for DGPAG.

Testing for antireticulin antibodies in patients with celiac disease is obsolete: a review of recommendations for serologic screening and the literature

Celiac disease (CD) is an autoimmune disorder that occurs in genetically susceptible individuals of all ages and is triggered by immune response to gluten and related proteins. The disease is characterized by the presence of HLA-DQ2 and/or -DQ8 haplotypes, diverse clinical manifestations, gluten-sensitive enteropathy, and production of several autoantibodies of which endomysial, tissue transglutaminase, and deamidated gliadin peptide antibodies are considered specific. Although antireticulin antibodies (ARA) have historically been used in the evaluation of CD, these assays lack optimal sensitivities and specificities for routine diagnostic use. This minireview highlights the advances in CD-specific serologic testing and the rationale for eliminating ARA from CD evaluation consistent with recommendations for diagnosis.

Prospective antibody case finding of coeliac disease in type-1 diabetes children: need of biopsy revisited

AIM

To evaluate whether coeliac disease (CD) can be diagnosed by measuring autoantibodies without small-intestinal mucosal biopsies in children with type 1 diabetes.

METHODS

Case finding of CD was undertaken in 181 consecutive IgA-competent children with type 1 diabetes using transglutaminase 2 (TG2) and endomysial IgA antibody (EMA) tests in serum and the rapid point of care test in fingertip whole-blood sample. Endoscopy with intestinal biopsies was recommended for patients with high TG2-IgA titres (>96 U) and in children with lower positive tests if either the EMA test or the rapid point of care test was additionally positive. The duodenal mucosal biopsies were graded according to the Marsh classification.

RESULTS

The TG2-IgA test had a 15.5% and the EMA test a 6.0% seropositivity. All seven biopsied high-titre TG2-IgA-positive children were symptom free and found to have CD (Marsh 3 type lesion). These patients were also positive for EMA and in the rapid point of care test. Lower titre TG2-IgA-positive children had histological Marsh 1 to 3a lesions.

CONCLUSIONS

None of the type 1 diabetes children with high TG2-IgA titres would have needed endoscopy with duodenal biopsies to reach a CD diagnosis. Lower TG2-IgA-positive patients need to be biopsied.

Concomitant autoantibodies in newly diagnosed diabetic children with transient celiac serology or proven celiac disease

BACKGROUND

We previously demonstrated that children with Type 1 Diabetes Mellitus (T1DM) may have transiently elevated tissue transglutaminase antibodies (TTG) on a gluten-containing diet. This study aimed to examine if the presence of autoantibodies in newly diagnosed T1DM differs between patients with celiac disease and those with transient celiac serology.

METHODS

Forty children were identified who had been diagnosed with T1DM between 2003 and 2009 and who had elevated serum IgA-TTG antibody levels at diagnosis. Blood samples were collected for measurement of insulin (IA-2A) antibodies, islet cell antigen (ICA) antibodies, glutamic acid decarboxylase (GAD) antibodies, thyroglobulin (TgAb) antibodies, and thyroid peroxidase (TPO) antibodies. Children diagnosed with celiac disease (CD; group 1, n=23) and children in whom TTG antibody levels spontaneously normalized over time (group 2, n=17) were compared.

RESULTS

No significant differences in positivity rates between groups 1 and 2 were found for any of the autoantibodies tested. The respective findings were as follows: IA-2A 50% and 47.1% (p=0.855); ICA 77.3% and 76.5% (p=0.953); GAD 27.3% and 52.9% (p=0.102). Thyroid antibodies were found positive in a limited number of patients: TgAb 4.5% and 11.8%; TPO 4.5% and 11.8%. In addition, antibody titer levels did not differ significantly for all autoantibodies. Difference in occurrence of clinical or subclinical thyroid disease did not reach significance (4.3% vs. 29.4%; p=0.07). Age was positively correlated with the presence of thyroglobulin and thyroid peroxidase antibodies, and negatively correlated with the presence of insulin antibody.

CONCLUSION

Neither the number of concomitant autoantibodies nor their titers in newly diagnosed T1DM differed between patients with proven CD and those with transient TTG serology.

Are we diagnosing too many people with coeliac disease?

This review will try to address the question of whether we are diagnosing too many people with coeliac disease. The key reasons for diagnosing coeliac disease may be that it is a common condition affecting up to 1% of the adult population. Delays in diagnosis are common. The average time delay reported by Coeliac UK (National Medical Patient Charity), for patients with symptoms prior to the diagnosis being made is 13 years. For every adult case detected, it is estimated that there are eight cases not detected. Patients with coeliac disease have an associated morbidity and mortality. In addition, quality of life studies suggest that the majority of patients benefit from a gluten-free diet (GFD). Furthermore, the GFD reduces or alleviates the risk of the associated complications. All of these facts could even be used to support the argument for screening! However, conversely the tests for coeliac disease are not 100% sensitive and specific. In addition, we do not know whether patients with milder symptoms will derive less benefit from treatment and are at less risk of complications. Furthermore, evidence presented in this review suggests that actual outcomes for screening studies in an adult population have revealed poor uptake and subsequently difficulties with adherence. What little published data that are available also infers that individuals recognised through screening programmes could have been detected if carefully questioned for symptoms. There is evidence to suggest that diagnosing celiac disease is cost-effective and that the diagnostic costs are offset by reduced medical expenditures, reduced hospital and general practice attendances, but this view depends on the population prevalence of coeliac disease. We believe on the basis of the evidence presented in this review that we are not diagnosing too many adults with coeliac disease. However, the authors consider case-finding with a low threshold for serological testing to be the optimal approach. If you look for coeliac disease you will find it.

Prevalence and natural history of potential celiac disease in at-family-risk infants prospectively investigated from birth

OBJECTIVE

To evaluate the frequency and the natural history of potential (serology positive/Marsh 0-1 histology) celiac disease (CD) in children with a family risk of CD and factors associated with potential instead of overt (serology positive/Marsh 2-3 histology) CD expression.

STUDY DESIGN

Two-year follow-up study of 96 children (57 females; mean age: 29 ± 12 months) prospectively investigated from birth with: (1) a CD-affected first-degree relative; (2) positivity of serum IgA anti-tissue transglutaminase (tTG) or IgG antigliadin and IgA deficiency; and (3) the results of small intestinal biopsy. Children with potential CD were advised to remain on a gluten containing diet, repeat the celiac antibodies every 6 months, and to have an intestinal biopsy performed in case of persistently high anti-tTG level. Factors discriminating between potential and overt CD were analyzed by decision tree analysis based on the C4.5 algorithm.

RESULTS

Twenty-four children had potential and 72 overt CD. The stronger predictors of potential CD were lack of symptoms, anti-tTG level lower than 11-fold the upper normal limit, age lower than 24 months, and breastfeeding longer than 8 months. Eighteen out of 21 (86%) patients with potential CD continuing a gluten-containing diet became antibody negative, 1/21 (5%) developed overt CD, and 2/21 (9%) had fluctuating antibodies levels after 2 years.

CONCLUSIONS

The prevalence of potential CD and the percentage of short-term loss of CD-related-antibodies are high in infants at-family-risk for CD. In symptomless children with a positive celiac serology, the decision of performing an intestinal biopsy should be preceded by a period of repeated serological testing.

Type 1 diabetes associated and tissue transglutaminase autoantibodies in patients without type 1 diabetes and coeliac disease with confirmed viral infections

Coeliac disease and type 1 diabetes are autoimmune diseases that may share the same initiating environmental factors. In this study, the occurrence of type 1 diabetes associated autoantibodies (GADA and IA-2A) and tissue transglutaminase autoantibodies (TGA) was determined in patients with confirmed viral infections and no signs of type 1 diabetes or coeliac disease. Serum samples from 82 Cuban patients tested positive for PCR and IgG specific to enterovirus (HEV, serotype echovirus 16, 20 samples), Epstein-Barr virus (EBV, 20 samples), cytomegalovirus (CMV, 21 samples), and hepatitis C virus (HCV, 21 samples); and sera from 164 controls negative serologically to EBV, CMV, HCV, and echovirus 16 were enrolled in the study. All subjects were screened for GADA, IA-2A, and TGA. The prevalence of TGA in patients infected with HEV, EBV, CMV, or HCV was 55% (11/20), 25% (5/20), 9.5% (2/21), and 9.5% (2/21), respectively. GADA and IA-2A were found in 15% (3/20) and 25% (5/20) of patients infected with HEV. None of the patients infected by EBV, CMV, and HCV had GADA or IA-2A. All children infected with HEV who were positive for type 1 diabetes-associated autoantibodies were also TGA-positive. None of the sera from uninfected subjects were positive for GADA, IA-2A or TGA. In conclusion, TGA can develop during infection with HEV, EBV, CMV, or HCV, while the emergence of islet cell related autoantibodies is restricted to HEV infections. The findings suggest that HEV may be a shared environmental factor for the development of islet and gut-related autoimmunity.

Spontaneous normalization of anti-tissue transglutaminase antibody levels is common in children with type 1 diabetes mellitus

BACKGROUND

The prevalence of celiac disease among type 1 diabetes mellitus (T1DM) patients is 5-10 times higher than in the general population. Thus, evaluation of celiac serology is indicated at diagnosis of T1DM and on follow up.

AIM

This study was prompted by the observation that elevated anti-TTG antibody levels in diabetic children may spontaneously normalize despite continued consumption of gluten. The objective of the study was to investigate the prevalence of this phenomenon and associated factors.

MATERIALS AND METHODS

The files of all children diagnosed with type 1 diabetes mellitus from 2003-2009 at a tertiary pediatric medical center were reviewed for those with elevated serum levels of anti-TTG antibody. Clinical, medical, laboratory, and treatment data were collected. Findings were compared between patients diagnosed with celiac disease and patients with initially elevated anti-TTG antibody levels that spontaneously normalized.

RESULTS

Forty-eight of the 738 patients with type 1 diabetes attending our center (6.5%) had elevated anti-TTG antibody blood levels. Celiac disease was diagnosed in 23, and anti-TTG antibody levels normalized in 17 (35.4%), all of whom consumed gluten. At one-year follow-up, there was no significant difference between the groups in HbA1c level or change in anthropometric measurements.

CONCLUSION

Physicians treating children with type 1 diabetes and mildly elevated anti-TTG antibody levels might consider 12-month serologic follow-up on a gluten-containing diet rather than immediate duodenal biopsy.

Are immunoglobulin A anti-gliadin antibodies helpful in diagnosing coeliac disease in children younger than 2 years?

The usefulness of immumoglobulin (Ig) A antibodies to gliadin (AGA-IgA) in addition to IgA anti-endomysium and tissue transglutaminase antibodies was evaluated in 4122 children younger than 2 years with a suspicion of coeliac disease (CD). Eight percent (312/4122) displayed IgA anti-endomysium and/or IgA anti-tissue transglutaminase, whereas 2.1% (85/4122) displayed only AGA-IgA. Clinical data were obtained for 62 of 85 children with isolated AGA-IgA, and 33 children underwent a duodenal biopsy. Histologically proven CD was established for 5 patients, whereas 57 children were diagnosed to experience other diseases. The systematic detection of AGA-IgA using native gliadin conferred no additional diagnostic benefit for the diagnosis of CD in children younger than 2 years of age, except for rare cases.

European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for the diagnosis of coeliac disease

OBJECTIVE

Diagnostic criteria for coeliac disease (CD) from the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) were published in 1990. Since then, the autoantigen in CD, tissue transglutaminase, has been identified; the perception of CD has changed from that of a rather uncommon enteropathy to a common multiorgan disease strongly dependent on the haplotypes human leukocyte antigen (HLA)-DQ2 and HLA-DQ8; and CD-specific antibody tests have improved.

METHODS

A panel of 17 experts defined CD and developed new diagnostic criteria based on the Delphi process. Two groups of patients were defined with different diagnostic approaches to diagnose CD: children with symptoms suggestive of CD (group 1) and asymptomatic children at increased risk for CD (group 2). The 2004 National Institutes of Health/Agency for Healthcare Research and Quality report and a systematic literature search on antibody tests for CD in paediatric patients covering the years 2004 to 2009 was the basis for the evidence-based recommendations on CD-specific antibody testing.

RESULTS

In group 1, the diagnosis of CD is based on symptoms, positive serology, and histology that is consistent with CD. If immunoglobulin A anti-tissue transglutaminase type 2 antibody titers are high (>10 times the upper limit of normal), then the option is to diagnose CD without duodenal biopsies by applying a strict protocol with further laboratory tests. In group 2, the diagnosis of CD is based on positive serology and histology. HLA-DQ2 and HLA-DQ8 testing is valuable because CD is unlikely if both haplotypes are negative.

CONCLUSIONS

The aim of the new guidelines was to achieve a high diagnostic accuracy and to reduce the burden for patients and their families. The performance of these guidelines in clinical practice should be evaluated prospectively.

Persistently positive gliadin antibodies without transglutaminase antibodies in the elderly: gluten intolerance beyond coeliac disease

BACKGROUND

The specificity of the conventional gliadin antibody test is considered low.

AIMS

We explored whether gliadin antibody(AGA)-positivity without tissue transglutaminase antibodies (tTGA) is persistent in the elderly population and whether such positivity indicates overt or potential coeliac disease in genetically predisposed individuals.

METHODS

AGA and tissue transglutaminase antibody were measured in 2089 elderly individuals twice with a three-year interval. AGA-positive but tissue transglutaminase antibody-negative subjects with coeliac-type human leucocyte antigen (HLA) were examined and underwent gastroduodenal endoscopy (cases). Small-bowel mucosal villous morphology and densities of CD3+ and γδ+ intraepithelial lymphocytes and the occurrence of tissue transglutaminase-specific IgA deposits were analysed. Randomly selected persistently AGA-negative age- and sex-matched subjects served as controls.

RESULTS

AGA-positivity was persistent in 81% of those initially positive. Amongst the 49 clinically studied and 36 endoscopied cases only one (2.8%) had coeliac disease. Many (54%) showed signs of inflammation in the biopsy, without villous atrophy. Coeliac-type HLA was not over-represented in the persistently AGA-positive compared to the general population. Persistently AGA-positive coeliac-type HLA-positive subjects had more gastrointestinal symptoms than AGA-negative controls.

CONCLUSIONS

AGA-positivity is often persistent. Overt coeliac disease is seldom found behind persistent AGA-positivity, but this characteristic is associated with mucosal inflammation and gastrointestinal symptoms at least in HLA-positive individuals.

Is it time to screen for adult coeliac disease?

To meet the principles of screening as described by Wilson and Jungner a disease must be common, a significant health burden, detectable and treatable. The key lies in the early detection and alteration of the natural history of disease. Coeliac disease affects 1 in 100 people. Despite this patients frequently have delays in diagnosis or may remain undetected. There is an associated morbidity and mortality which can be effectively treated by simple means of a gluten-free diet. For these reasons coeliac disease has been suggested as appropriate for mass screening. However, there are caveats to this: a complex clinical spectrum, a natural history that is imperfectly understood, overestimation of morbidity and mortality, poor adherence to treatment, and costs of service provision may argue against the time being right for mass screening. This review article provides the most contemporary overview and reference base to allow any clinician to understand the benefits or limitations of a screening programme for adult coeliac disease.