Development of celiac disease-associated antibodies in offspring of parents with type I diabetes

Extra-intestinal manifestations of Celiac disease in children: their prevalence and association with human leukocyte antigens and pathological and laboratory evaluations

BACKGROUND

Celiac disease (CD) is an autoimmune disease caused by gluten intake. Traditionally CD was believed to be a disease of the gut, although a wide range of extra-intestinal manifestations (EIM) was recognized. The exact prevalence of EIM and the associated risk factors have not been well studied.

AIM

We aimed to assess the prevalence of EIM in children with CD and their association with human leukocyte antigen (HLA) typing, and pathological and laboratory indices.

METHOD

We conducted a cross-sectional study on children and adolescents with a definite diagnosis of CD. They were followed in the main Celiac Clinic of Southern Iran.

RESULTS

We included 204 children who were visited between 2012 and 2017. Nearly 85% of them were positive for HLA-DQ2 and 40.6% for HLA-DQ8. The most prevalent intestinal complaints reported were abdominal pain (42.6%) and chronic constipation (19.1%). Failure-to-thrive (32.7%), iron deficiency anemia (25%), short stature (20.5%), and eczema (18.6%) were the most common EIMs. However, failure-to-thrive and short stature were presented at significantly younger ages, whereas those patients with concomitant type 1 diabetes mellitus (DM) were significantly older. We also found significant relationships between autoimmune thyroid disease and HLA-DQ5, and the presence of headaches with HLA-DQ7. The prevalence of HLA types of DQ2, DQ8, DQ6, and DQ7 significantly varied among different Marsh groups. Patients who were positive for HLA-DQ8, were significantly older, taller, and weightier. No significant association was found between HLA types and any of the gastrointestinal symptoms, anti-tTG and compliance to gluten free diet. Moreover, there were no statistically significant differences detected between the presence of each individual EIM, the level of IgA anti-tTG, sex, and Marsh typing.

CONCLUSION

This study highlights the presence of EIM in CD and their associated factors. We show the potential role of HLA typing in some EIMs, which may shed light for future studies.

A classification and regression tree analysis identifies subgroups of childhood type 1 diabetes

Background

Diabetes in childhood and adolescence includes autoimmune and non-autoimmune forms with heterogeneity in clinical and biochemical presentations. An unresolved question is whether there are subtypes, endotypes, or theratypes within these forms of diabetes.

Methods

The multivariable classification and regression tree (CART) analysis method was used to identify subgroups of diabetes with differing residual C-peptide levels in patients with newly diagnosed diabetes before 20 years of age (n=1192). The robustness of the model was assessed in a confirmation and prognosis cohort (n=2722).

Findings

The analysis selected age, haemoglobin A1c (HbA1c), and body mass index (BMI) as split parameters that classified patients into seven islet autoantibody-positive and three autoantibody-negative groups. There were substantial differences in genetics, inflammatory markers, diabetes family history, lipids, 25-OH-Vitamin D3, insulin treatment, insulin sensitivity and insulin autoimmunity among the groups, and the method stratified patients with potentially different pathogeneses and prognoses. Interferon-ɣ and/or tumour necrosis factor inflammatory signatures were enriched in the youngest islet autoantibody-positive groups and in patients with the lowest C-peptide values, while higher BMI and type 2 diabetes characteristics were found in older patients. The prognostic relevance was demonstrated by persistent differences in HbA1c at 7 years median follow-up.

Interpretation

This multivariable analysis revealed subgroups of young patients with diabetes that have potential pathogenetic and therapeutic relevance.

Funding

The work was supported by funds from the German Federal Ministry of Education and Research (01KX1818; FKZ 01GI0805; DZD e.V.), the Innovative Medicine Initiative 2 Joint Undertaking INNODIA (grant agreement No. 115797), the German Robert Koch Institute, and the German Diabetes Association.

Genome-Wide Association Study-Guided Exome Rare Variant Burden Analysis Identifies IL1R1 and CD3E as Potential Autoimmunity Risk Genes for Celiac Disease

Celiac disease (CeD) is a multifactorial autoimmune enteropathy characterized by the overactivation of the immune system in response to dietary gluten. The molecular etiology of CeD is still not well-understood. Therefore, this study aims to identify potential candidate genes involved in CeD pathogenesis by applying multilayered system biology approaches. Initially, we identified rare coding variants shared between the affected siblings in two rare Arab CeD families by whole-exome sequencing (WES). Then we used the STRING database to construct a protein network of rare variants and genome-wide association study (GWAS) loci to explore their molecular interactions in CeD. Furthermore, the hub genes identified based on network topology parameters were subjected to a series of computational validation analyses like pathway enrichment, gene expression, knockout mouse model, and variant pathogenicity predictions. Our findings have shown the absence of rare variants showing classical Mendelian inheritance in both families. However, interactome analysis of rare WES variants and GWAS loci has identified a total of 11 hub genes. The multidimensional computational analysis of hub genes has prioritized IL1R1 for family A and CD3E for family B as potential genes. These genes were connected to CeD pathogenesis pathways of T-cell selection, cytokine signaling, and adaptive immune response. Future multi-omics studies may uncover the roles of IL1R1 and CD3E in gluten sensitivity. The present investigation lays forth a novel approach integrating next-generation sequencing (NGS) of familial cases, GWAS, and computational analysis for solving the complex genetic architecture of CeD.

Risk of pediatric celiac disease according to HLA haplotype and country

BACKGROUND

The presence of HLA haplotype DR3-DQ2 or DR4-DQ8 is associated with an increased risk of celiac disease. In addition, nearly all children with celiac disease have serum antibodies against tissue transglutaminase (tTG).

METHODS

We studied 6403 children with HLA haplotype DR3-DQ2 or DR4-DQ8 prospectively from birth in the United States, Finland, Germany, and Sweden. The primary end point was the development of celiac disease autoimmunity, which was defined as the presence of tTG antibodies on two consecutive tests at least 3 months apart. The secondary end point was the development of celiac disease, which was defined for the purpose of this study as either a diagnosis on biopsy or persistently high levels of tTG antibodies.

RESULTS

The median follow-up was 60 months (interquartile range, 46 to 77). Celiac disease autoimmunity developed in 786 children (12%). Of the 350 children who underwent biopsy, 291 had confirmed celiac disease; an additional 21 children who did not undergo biopsy had persistently high levels of tTG antibodies. The risks of celiac disease autoimmunity and celiac disease by the age of 5 years were 11% and 3%, respectively, among children with a single DR3-DQ2 haplotype, and 26% and 11%, respectively, among those with two copies (DR3-DQ2 homozygosity). In the adjusted model, the hazard ratios for celiac disease autoimmunity were 2.09 (95% confidence interval [CI], 1.70 to 2.56) among heterozygotes and 5.70 (95% CI, 4.66 to 6.97) among homozygotes, as compared with children who had the lowest-risk genotypes (DR4-DQ8 heterozygotes or homozygotes). Residence in Sweden was also independently associated with an increased risk of celiac disease autoimmunity (hazard ratio, 1.90; 95% CI, 1.61 to 2.25).

CONCLUSIONS

Children with the HLA haplotype DR3-DQ2, especially homozygotes, were found to be at high risk for celiac disease autoimmunity and celiac disease early in childhood. The higher risk in Sweden than in other countries highlights the importance of studying environmental factors associated with celiac disease. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.).

Extended family history of autoimmune diseases and phenotype and genotype of children with newly diagnosed type 1 diabetes

OBJECTIVE

Based on the concept of clustering autoimmunity, children with a positive family history of autoimmunity could be expected to have a different pathogenetic form of type 1 diabetes (T1D) and thus a stronger autoimmune reactivity against β-cells and an increased prevalence of the HLA-DR3-DQ2 haplotype.

DESIGN AND METHODS

We tested this hypothesis in a cross-sectional observational study from the Finnish Pediatric Diabetes Register. HLA class II genotypes and β-cell autoantibodies were analyzed, and data on the extended family history of autoimmunity and clinical markers at diagnosis were collected with a structured questionnaire from 1488 children diagnosed with T1D under the age of 15 years (57% males).

RESULTS

Only 23 children (1.5%) had another autoimmune disease (AID) known at diagnosis, and they had a milder metabolic decompensation at diabetes presentation. One-third (31.4%) had at least one relative with an AID other than T1D with affected mothers being overrepresented (8.2%) compared with fathers (2.8%). The children with a positive family history of other AIDs had higher levels of islet cell antibodies (P=0.003), and the HLA-DR3-DQ2 haplotype in the children was associated with celiac disease in the extended family (P<0.001), but not with an increased frequency of autoimmune disorders, in general.

CONCLUSIONS

Approximately one-third of children with newly diagnosed T1D have a first- and/or second-degree relative affected by an AID. Our data do not consistently support the hypothesis of differential pathogenetic mechanisms in such children.

Prevalence of celiac disease in omani children with type 1 diabetes mellitus: a cross sectional study

OBJECTIVE

Published studies on the prevalence of celiac disease in type 1 diabetes mellitus from the Arab World are scant. We aim to report the prevalence of celiac disease in Omani children with type 1 diabetes mellitus.

METHODS

Children with type 1 diabetes mellitus were prospectively screened for celiac disease, at Sultan Qaboos University Hospital, Muscat, Oman over a period of one year (June 2011 - May 2012). Serum anti tissue transglutaminase IgA, endomysial IgA antibodies and total IgA were measured for screening of celiac disease. Children with positive anti-tissue transglutaminase and/or endomysial IgA antibodies underwent endoscopy.

RESULTS

A total of 103 children with type 1 diabetes mellitus were initially included. Ten patients were lost to follow up. Ninety-three patients aged 2-17 years underwent screening for celiac disease. Sixteen patients had positive anti-tissue transglutaminase (17%). Fourteen patients underwent endoscopy with duodenal biopsies, while two were lost to follow-up. Five patients with positive anti-tissue transglutaminase had intestinal biopsy proven celiac disease. The prevalence of celiac disease is 5.5% in our cohort of children and adolescents with type 1 diabetes mellitus.

CONCLUSIONS

The prevalence of celiac disease in Omani children and adolescents with type 1 diabetes mellitus is similar to the World's reported prevalence, but is less than that reported for Middle Eastern Arab children. To our knowledge, this is the first reported study on the prevalence of celiac disease in Omani children with type 1 diabetes mellitus.

ACG clinical guidelines: diagnosis and management of celiac disease

This guideline presents recommendations for the diagnosis and management of patients with celiac disease. Celiac disease is an immune-based reaction to dietary gluten (storage protein for wheat, barley, and rye) that primarily affects the small intestine in those with a genetic predisposition and resolves with exclusion of gluten from the diet. There has been a substantial increase in the prevalence of celiac disease over the last 50 years and an increase in the rate of diagnosis in the last 10 years. Celiac disease can present with many symptoms, including typical gastrointestinal symptoms (e.g., diarrhea, steatorrhea, weight loss, bloating, flatulence, abdominal pain) and also non-gastrointestinal abnormalities (e.g., abnormal liver function tests, iron deficiency anemia, bone disease, skin disorders, and many other protean manifestations). Indeed, many individuals with celiac disease may have no symptoms at all. Celiac disease is usually detected by serologic testing of celiac-specific antibodies. The diagnosis is confirmed by duodenal mucosal biopsies. Both serology and biopsy should be performed on a gluten-containing diet. The treatment for celiac disease is primarily a gluten-free diet (GFD), which requires significant patient education, motivation, and follow-up. Non-responsive celiac disease occurs frequently, particularly in those diagnosed in adulthood. Persistent or recurring symptoms should lead to a review of the patient's original diagnosis to exclude alternative diagnoses, a review of the GFD to ensure there is no obvious gluten contamination, and serologic testing to confirm adherence with the GFD. In addition, evaluation for disorders associated with celiac disease that could cause persistent symptoms, such as microscopic colitis, pancreatic exocrine dysfunction, and complications of celiac disease, such as enteropathy-associated lymphoma or refractory celiac disease, should be entertained. Newer therapeutic modalities are being studied in clinical trials, but are not yet approved for use in practice. Given the incomplete response of many patients to a GFD-free diet as well as the difficulty of adherence to the GFD over the long term, development of new effective therapies for symptom control and reversal of inflammation and organ damage are needed. The prevalence of celiac disease is increasing worldwide and many patients with celiac disease remain undiagnosed, highlighting the need for improved strategies in the future for the optimal detection of patients.

Type 1 Diabetes: Etiology, Immunology, and Therapeutic Strategies

Type 1 diabetes (T1D) is a chronic autoimmune disease in which destruction or damaging of the beta-cells in the islets of Langerhans results in insulin deficiency and hyperglycemia. We only know for sure that autoimmunity is the predominant effector mechanism of T1D, but may not be its primary cause. T1D precipitates in genetically susceptible individuals, very likely as a result of an environmental trigger. Current genetic data point towards the following genes as susceptibility genes: HLA, insulin, PTPN22, IL2Ra, and CTLA4. Epidemiological and other studies suggest a triggering role for enteroviruses, while other microorganisms might provide protection. Efficacious prevention of T1D will require detection of the earliest events in the process. So far, autoantibodies are most widely used as serum biomarker, but T-cell readouts and metabolome studies might strengthen and bring forward diagnosis. Current preventive clinical trials mostly focus on environmental triggers. Therapeutic trials test the efficacy of antigen-specific and antigen-nonspecific immune interventions, but also include restoration of the affected beta-cell mass by islet transplantation, neogenesis and regeneration, and combinations thereof. In this comprehensive review, we explain the genetic, environmental, and immunological data underlying the prevention and intervention strategies to constrain T1D.

German new onset diabetes in the young incident cohort study: DiMelli study design and first-year results

BACKGROUND

Diabetes incidence in childhood and youth is increasing worldwide, including autoimmune and non-autoimmune cases. Recent findings suggest that there is a larger than expected proportion of type 2 diabetes in youth, and potential cases of intermediate diabetes phenotypes. Most pediatric diabetes registries focus on type 1 diabetes. Also, there is an absence of reliable data on type 2 diabetes incidence in youth.

AIMS

The DiMelli study aims to establish a diabetes incidence cohort registry of patients in Germany, diagnosed with diabetes mellitus before age 20 years. It will be used to characterize diabetes phenotypes by immunologic, metabolic, and genetic markers. DiMelli will assess the contribution of obesity and socio-demographic factors to the development of diabetes in childhood and youth.

METHODS

Recruitment of patients started in 2009, and is expected to continue at a rate of 250 patients per year.

RESULTS

84% of the 216 patients recruited within the first year were positive for multiple islet autoantibodies, 12% for one islet autoantibody, and 4% were islet autoantibody-negative. Patients with multiple islet autoantibodies were younger and had lower fasting C-peptide levels, compared to islet autoantibody-negative patients (median age 10.0 vs. 14.1 years, p < 0.01).

CONCLUSIONS

Results from the first year of the study show that DiMelli will help to reveal new knowledge on the etiology of diabetes, and the contribution of genetic predisposition and environmental risk factors to the different types of diabetes.

The prevalence and risk factors for coeliac disease among children and adolescents with type 1 diabetes mellitus

AIMS

Our aim was to determine in children with T1DM the prevalence of positive antibodies against tissue transglutaminase (anti-tTG IgA) as indices of coeliac disease (CD), as well as its clinical presentation, its determinants and its association with thyroid (anti-TG, anti-TPO) and pancreatic b-cell autoimmunity (anti-GAD).

METHODS

The study included 105 children and adolescents with T1DM, aged (mean±SD) 12.44±4.76 years, with a T1DM duration of 4.41±3.70 years.

RESULTS

Fifty of our patients (47.6%) were positive for anti-GAD, 9/105 (8.6%) for anti-tTG IgA and 21/105(20%) for anti-thyroid antibodies. The anti-tTG IgA (+) children, in comparison with the rest of the study population, were of younger age (9.31 vs. 12.74 years, p=0.038), shorter diabetes duration (2.16 vs. 4.62 years, p=0.056) and had mild growth impairment (height SDS: -0.55 vs. +0.20, p=0.055). Univariate logistic regression analysis revealed that the presence of anti-tTG IgA (+) was associated with younger age and shorter T1DM duration. Only 5/9 (55.6%) children with high titres of anti-tTG IgA developed mild gastrointestinal symptoms or growth retardation and had histological findings typical of CD.

CONCLUSIONS

The prevalence of anti-tTG IgA positivity among T1DM children was 8.6% and its occurrence was associated with younger age and short diabetes duration. Since CD presents in T1DM patients asymptomatically or with non-specific symptoms, periodic autoantibody screening is necessary for its early diagnosis.

Polyendocrinopathy in children, adolescents, and young adults with type 1 diabetes: a multicenter analysis of 28,671 patients from the German/Austrian DPV-Wiss database

OBJECTIVE

To investigate diabetes-specific autoantibodies and additional autoimmune phenomena in a large cohort of young patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Data from 28,671 patients <30 years with type 1 diabetes from 242 specialized centers in Germany and Austria were analyzed.

RESULTS

At least one beta-cell antibody was present in 81.6% of patients. beta-cell-Ab-negative patients were significantly younger at diabetes onset (P < 0.0001). A total of 19.6% had positive thyroid antibodies with female predominance (62%, P < 0.0001). Antibodies to tissue transglutaminase were present in 10.7%, with a significantly longer duration of diabetes (P < 0.0001). Parietal cell antibodies were found in 283 patients, associated with older age (P < 0.001), and adrenal antibodies were present in 94 patients. In 575 patients, at least three different autoimmune phenomena were present.

CONCLUSIONS

Thyroid autoimmunity and antibodies suggestive for celiac disease are the most prevalent additional immune phenomena in type 1 diabetes. Parietal/adrenal antibodies are rare.

Risk factors in familial forms of celiac disease

Celiac disease has been reported in up to 2% of some European populations. A similar risk has been identified in the America and Australia where immigration of Europeans has occurred. Moreover, an increasing number of celiac disease patients are being identified in many Asian countries, including China and India. Finally, celiac disease has also been detected in Asian immigrants and their descendants to other countries, such as Canada. Within these so-called "general" celiac populations, however, there are specific high risk groups that have an even higher prevalence of celiac disease. Indeed, the single most important risk factor for celiac disease is having a first-degree relative with already-defined celiac disease, particularly a sibling. A rate up to 20% or more has been noted. Risk is even greater if a specific family has 2 siblings affected, particularly if a male carries the human leukocyte antigen-DQ2. Both structural changes in the small bowel architecture occur along with functional changes in permeability, even in asymptomatic first-degree relatives. Even if celiac disease is not evident, the risk of other autoimmune disorders seems significantly increased in first-degree relatives as well as intestinal lymphoma. Identification of celiac disease is important since recent long-term studies have shown that the mortality of celiac disease is increased, if it is unrecognized and untreated.

Age at development of type 1 diabetes- and celiac disease-associated antibodies and clinical disease in genetically susceptible children observed from birth

OBJECTIVE

To compare the ages and sequence in which antibodies associated with type 1 diabetes and celiac disease appear and overt diseases develop in children with an HLA-conferred susceptibility to both diseases.

RESEARCH DESIGN AND METHODS

We observed 2,052 children carrying genetic risks for both type 1 diabetes and celiac disease from birth until the median age of 5.7 years and analyzed diabetes- and celiac disease-associated antibodies in serum samples collected at 3- to 12-month intervals. Diabetes was confirmed by World Health Organization criteria and celiac disease by duodenal biopsies.

RESULTS

Altogether 342 children seroconverted to positivity for at least one diabetes-associated autoantibody and 88 to positivity for at least one celiac disease-associated antibody at the median ages of 3.0 and 1.5 years, respectively (P < 0.001). If only children with biochemically defined diabetes-associated autoantibodies against insulin, GAD, or IA-2A protein (n = 146) and children with tissue transglutaminase autoantibodies were compared (n = 86), the median seroconversion ages were 2.5 and 3.0 years (P = 0.011). Fifty-one children progressed to overt diabetes at 4.5 years and 44 children to celiac disease at 4.3 years (P = 0.257). Of the 19 children who developed both diabetes- and celiac disease-associated antibodies, 3 progressed to both diabetes and celiac disease.

CONCLUSIONS

Children with HLA-conferred susceptibility to type 1 diabetes and celiac disease develop celiac disease-associated antibodies mostly at a younger age or the same age at which they develop diabetes-associated autoantibodies. Clinical diabetes and celiac disease are commonly diagnosed at the same median age.

Screening detects a high proportion of celiac disease in young HLA-genotyped children

BACKGROUND AND AIMS

Celiac disease is associated with tissue transglutaminase autoantibodies (tTGAb) and the human leukocyte antigen (HLA)-risk alleles DQB1*02 and DQB1*0302. The aim was to estimate the proportion of undiagnosed celiac disease in children with HLA risk at 3 years of age.

PATIENTS AND METHODS

From a population-based HLA-DQ screening study of newborns born between June 2001 and August 2004 in the southern part of Sweden, 6206 children with HLA-risk alleles were identified and asked to participate at a mean 3.3 +/- 0.4 years of age. As controls, 7654 children with HLA-nonrisk alleles were asked to participate. In all, 1620 (26.1%) children with HLA risk and 1815 (23.7%) controls were screened for tTGAb using radioligand-binding assays. Celiac disease was established by intestinal biopsy in children with a confirmed positive tTGAb test.

RESULTS

Twenty-three children reported already having clinically diagnosed celiac disease and did not participate further. In children with HLA-risk genotypes, 73 of 1620 (4.5%, 95% CI 3.5%-5.5%) were tTGAb-positive compared with none of 1815 from the controls (P < 0.0001). Seventy-one children underwent biopsy (1 refused biopsy and 1 biopsy failed), of whom 56 of 1618 (3.5%, 95% CI 2.6%-4.4%) had damaged intestinal mucosa classified as celiac disease. The ratio between clinically and screening detected celiac disease in this study was 1:2.4 (23:56).

CONCLUSIONS

The proportion of clinically undetected celiac disease may be particularly high among 3-year-old children with HLA-DQB1*02 and DQB1*0302 in Sweden, where these 2 HLA-risk alleles frequently occur.

Endocrine autoimmunity in families with type 1 diabetes: frequent appearance of thyroid autoimmunity during late childhood and adolescence

AIMS/HYPOTHESIS

Thyroid autoimmunity clusters with other endocrine and non-endocrine forms of autoimmunity. The aim of this study was to determine the chronological appearance of thyroid autoantibodies in relation to other forms of autoimmunity in at-risk children.

METHODS

The BABYDIAB study follows children of parents with type 1 diabetes. Children born in Germany between 1989 and 2000 were recruited at birth and followed up at 9 months and at 2, 5, 8, 11, 14 and 17 years. Antibodies to thyroid peroxidase were measured in samples taken at the last study visit in 1,489 children and in all previous samples in children who tested positive. Islet antibodies and antibodies to 21-hydroxylase and transglutaminase were also measured in all children. Median follow-up was 8 years.

RESULTS

The cumulative risk for developing antibodies to thyroid peroxidase was 20.3% (95% CI 12.3-28.3) by age 14 years. The risk was increased in girls (adjusted HR 2.0; 95% CI 1.2-3.4; p = 0.008), in children who had multiple first-degree family history of type 1 diabetes (adjusted HR 3.3; 95% CI 1.4-8.0; p = 0.006) and in children who also had antibodies to GAD (adjusted HR 3.0; 95% CI 1.5-5.9; p = 0.001). Thyroid peroxidase antibody appearance was most common from age 8 years and was often the last autoantibody to develop in children with other autoantibodies.

CONCLUSIONS/INTERPRETATION

Among children of patients with type 1 diabetes, the appearance of thyroid autoantibodies is frequent, is not synchronous to the appearance of other autoantibodies and is most common in late childhood and adolescence.

Celiac disease: diagnosis, autoimmune mechanisms and treatment

Celiac disease is a systemic autoimmune disorder triggered by the ingestion of gluten found in wheat and related grains. Once considered rare, celiac disease is now thought to affect more than one in 100 individuals, and is commonly associated with other autoimmune disorders. It predisposes patients to an increased risk of malignancy if left untreated. Celiac disease is HLA restricted as only HLA-DQ2 and -DQ8 are able to bind deamidated gluten with sufficient affinity to trigger an immune response. Both cellular and humoral immune activation occur, leading to local tissue damage and antibody formation. These antibodies, primarily to tissue transglutaminase, are the basis for highly accurate serologic testing, although the gold standard for celiac disease diagnosis remains small intestinal biopsy. Currently, the only treatment for celiac disease is a life-long gluten-free diet, although multiple novel therapeutic modalities are being studied. Although most individuals with celiac disease respond completely to gluten withdrawal, 10-20% have persistent symptoms at some point during their course and less than 1% develop refractory celiac disease, an entity of substantial morbidity.

Development of autoimmunity to transglutaminase C in children of patients with type 1 diabetes: relationship to islet autoantibodies and infant feeding

AIMS/HYPOTHESIS

Coeliac disease and transglutaminase antibodies are common in patients with type 1 diabetes and their relatives. We investigated the development of transglutaminase antibodies and analysed potential risk factors for coeliac disease autoimmunity in first-degree relatives of patients with type 1 diabetes.

METHODS

The study was conducted by prospective observational follow-up from birth of 1,511 children at increased risk of type 1 diabetes or coeliac disease born in Germany between 1989 and 2000. Mean follow-up was to age 7.6 years. Children were tested for transglutaminase and islet autoantibodies. Children were classified as transglutaminase antibody-positive if antibodies were detected by both ELISA and radiobinding assays.

RESULTS

The risk of developing transglutaminase antibodies was 4.9% by age 8 years (n=63; 95% CI, 3.7-6.1%). Transglutaminase antibodies developed at an older age than islet autoantibodies (median age, 4.9 vs 2.3 years; p<0.005), and only three children developed both transglutaminase antibodies and islet autoantibodies. Multivariate analysis indicated an increased risk of transglutaminase antibodies in children with the HLA-DRB1*03 allele (hazard ratio for heterozygous DR3, 5.5; 95% CI, 2.9-10.2; hazard ratio for homozygous DR3, 16.2; 95% CI, 6.7-39; p<0.0001) and in children with impaired uterine growth (birth weight < or = 1st percentile, hazard ratio, 3.1; 95% CI, 1.1-7.8, p=0.03). Neither breast-feeding or its duration nor the age of first exposure to gluten was associated with the risk of developing transglutaminase antibodies.

CONCLUSIONS/INTERPRETATION

Coeliac disease autoimmunity is initiated later than islet autoimmunity in children who are at risk. An influence of infant nutrition on the development of coeliac disease autoimmunity could not be confirmed in this prospective study.

Serological and clinical comparison of children and adults with anti-endomysial antibodies

We compared serological and clinical presentation of 38 adults (5 males, 33 females) and 37 children (15 boys, 22 girls) with anti-endomysial antibodies (AEA).AEA, antinuclear (ANA), anti-parietal (APA), anti-thyroid microsomal (ATMA), anti-thyreoglobulin (ATGA), anti-smooth muscle (SMA) and anti-mitochondrial (AMA) antibodies were detected by IIF. Anti-tissue transglutaminase (tTG), anti-extractable nuclear antigens (ENA) and anti-actin (AAA) antibodies were studied by ELISA. There were no differences in frequency of ANA, APA, ATGA, SMA, AMA and AAA in children and adults. ATMA (p < 0.001) and anti-ENA (p < 0.05) positivity were more frequently found in adults. Anti-Ro/SSA had 7/38 adults and 1/37 children (p < 0.05). Adults had more frequently silent form of celiac disease associated with autoimmune diseases (p < 0.001). We are the first to demonstrate that in spite of no difference in ANA positivity in adults and children, ANA in adults more frequently target ENA, especially Ro/SSA antigen. The reason for this ANA specificity could be the longer gluten exposure in adults.

Dietary proteins as environmental modifiers of type 1 diabetes mellitus

Type 1 diabetes is an autoimmune disease in which the patient's immune system destroys the insulin-secreting beta-cells in the pancreatic islets of Langerhans. A majority of cases is thought to occur as a result of gene-environment interactions. The identity of the environmental factors remains unknown mainly because of the difficulty in linking past exposures with later disease development. Overall, the data suggest a model in which individuals develop diabetes by several different pathways, each influenced by numerous genetic and environmental variables. The most investigated environmental factors are diet and viruses. In this review, we examine the evidence that the source of dietary proteins can modify diabetes outcome, describe new approaches to identify candidate diabetes-related dietary agents, examine possible links with gut dysfunction, discuss some of the limitations, and propose a multifactorial model for dietary modification of diabetes. The key to diabetes pathogenesis, its prevention, and the ultimate success of beta-cell replacement therapies lies in understanding how the environment controls disease expression. Dietary proteins could be one of these keys.

Screening for celiac disease in Tunisian patients with Graves’ disease using anti-endomysium and anti-tissue transglutaminase antibodies

OBJECTIVE

Celiac disease (CD) can be associated with autoimmune thyroid diseases. The aim of this study was to screen for CD in patients with Graves' disease in Tunisia.

PATIENTS AND METHODS

Sera from 161 patients with Graves' disease were tested for IgA class anti-endomysium antibodies (AEA) using indirect immunofluorescence on cryostat sections of human umbilical cord and for IgA class anti-human tissue transglutaminase antibodies (AtTG) by ELISA.

RESULTS

AEA were positive in 6 out of 161 (3.7%) patients with Graves' disease and all 6 patients were also positive for AtTG. Four of these 6 patients with positive serological markers of CD underwent duodenal biopsy; three had marked villous atrophy, one has normal histological picture and two did not agree to undergo biopsy. The prevalence of biopsy confirmed CD in patients with Graves' disease was 1.86% (3/161).

CONCLUSION

Patients with Graves' disease are at substantial risk of CD and therefore antibody screening for CD may be included in the work-up of these patients. Either AEA or AtTG may be used.

Prospective screening for biopsy proven coeliac disease, autoimmunity and malabsorption markers in Belgian subjects with Type 1 diabetes

AIMS

To determine prospectively the prevalence of biopsy proven coeliac disease (CD) in an adult Type 1 diabetic population from Belgium with regards to associated auto-immunity and malabsorption.

METHODS AND RESULTS

Determination in 400 Type 1 diabetic patients of serum anti-endomysial and/or anti-transglutaminase auto-antibodies. All subjects with abnormal serology underwent an intestinal biopsy. Ten patients (2.5%) had positive antibodies. Diagnosis of CD was confirmed by an intestinal biopsy. Eight patients were symptom-free, although laboratory findings suggesting malabsorption were prominent in the presence of CD [microcytic anaemia, iron and folate deficiencies, low levels of 25(OH)vitamin D3, calcium and cholesterol]. Other auto-immune conditions, especially vitiligo, were found in patients with CD.

CONCLUSIONS

Asymptomatic coeliac disease occurs frequently in adult Type 1 diabetic patients, and is often associated with subclinical malabsorption. Screening should be part of routine evaluation, to implement life-long dietary gluten avoidance.

High prevalence of coeliac disease in siblings of children with type 1 diabetes

Coeliac disease has been shown to occur more frequently among first-degree relatives of diabetic patients than in the general population. Our objective was to assess the prevalence of endomysium antibodies (EMA) in non-diabetic siblings of Czech diabetic children and to evaluate the effects of HLA-DQ polymorphisms in determining the genetic susceptibility to coeliac disease (CD) in these subjects. We investigated 240 siblings of diabetic children from 213 families (125 males and 115 females, aged 12.6+/-4.9 years, mean +/- SD). All subjects were tested for the total IgA level to exclude IgA deficiency, and for endomysium IgA to disclose CD. In five IgA-deficient subjects, anti-gliadin IgG was used instead. Small bowel biopsy was offered to subjects with confirmed positive EMA. The HLA-DQA1, -DQB1 genotypes were determined using PCR-SSP. Positive EMA were found in 9/240 (3.8%) subjects (three males, six females). The biopsy confirmed CD in six children, two had a normal mucosal finding and one refused the biopsy. The HLA-DQ2 polymorphism was more frequent among siblings with EMA (seven of nine) than in siblings without EMA (33%), corrected P = 0.031.

CONCLUSION

The 3.8% frequency of coeliac disease found in siblings of diabetic children is close to the 4.3% found previously in Czech children with type 1 diabetes mellitus and is substantially higher than the rate in the healthy children population.

The temporal relationship between the onset of type 1 diabetes and celiac disease: a study based on immunoglobulin a antitransglutaminase screening

OBJECTIVE

The association of celiac disease (CD) and type 1 diabetes is now clearly documented. Immunoglobulin A (IgA) antitransglutaminase antibodies were measured to determine the prevalence of celiac disease in a diabetic population of children and to determine the temporal relationship between type 1 diabetes onset and CD.

METHODS

We measured IgA antitransglutaminase antibodies using human recombinant antigen in parallel with classical markers (IgA and IgG antigliadin, IgA antiendomysium) in 284 children with diabetes.

RESULTS

In the population studied, the prevalence of CD was 3.9% (11 of 284). Two cases of CD were diagnosed before the onset of diabetes, and in 8 patients, the diagnoses of CD and diabetes were concomitant, suggesting that CD was present before the onset of diabetes. In 1 case, a girl who presented with thyroiditis, serology for CD became positive after diabetes had been diagnosed.

CONCLUSION

An excellent correlation was observed between IgA antiendomysium and IgA antitransglutaminase antibodies. We therefore propose using IgA antitransglutaminase as a screening test for practical reasons. Furthermore, IgA antitransglutaminase levels and mucosa abnormalities were closely correlated. The presence of antitransglutaminase antibodies should alert pediatricians to the atypical forms of CD. This study indicates that CD is most often present before the onset of diabetes.

Coeliac disease in Iranian type I diabetic patients

BACKGROUND

The association between coeliac disease and type I diabetes mellitus has been evaluated in some previous studies, but its prevalence in Iranian diabetic patients remains unknown.

AIM

To evaluate the prevalence of coeliac disease in patients with type I diabetes mellitus in Iran.

PATIENTS

A total of 250 consecutive patients (102 male and 148 female) with type I diabetes mellitus.

METHODS

Total serum immunoglobulin A level and immunoglobulin A endomysial antibody was measured for all patients. Endoscopy and biopsy of the duodenum were performed for immunoglobulin A endomysial antibody-positive patients and pathologic evaluation was done according to modified Marsh classification.

RESULT

The mean age of the patients was 18.7 years (range: 2-55 years). Total serum immunoglobulin A was in the normal range for all patients. Immunoglobulin A endomysial antibody was positive in six (2.4%) patients (all of them were females; P = 0.04). Duodenal biopsy samples revealed grade I in two patients, grade II in three patients and grade IIIb in one patient (modified Marsh classification). Patients with coeliac disease and diabetes mellitus were older than patients with diabetes mellitus alone (mean age: 29.5 years versus 18.4 years; P < 0.001). There was a trend for longer duration of diabetes mellitus in coeliac patients than in patients without it (mean age: 17.3 years versus 12.5 years; P = 0.16).

CONCLUSION

The prevalence of coeliac disease in Iranian patients with type I diabetes mellitus is relatively high (2.4%). Since almost half of the patients with coeliac disease are asymptomatic, all patients with type I diabetes mellitus should be screened for coeliac disease regardless of the presence of symptoms, at diagnosis of diabetes mellitus and with regular intervals in the follow up.

Extrapancreatic autoimmune manifestations in type 1 diabetes patients and their first-degree relatives: a multicenter study

OBJECTIVE

To investigate the prevalence of autoimmune diseases in young patients (probands) with type 1 diabetes and their first-degree relatives, and to determine the spectrum of extrapancreatic manifestations in these subjects.

RESEARCH DESIGN AND METHODS

The study population included 109 probands age 13 +/- 4.9 years and 412 first-degree relatives age 28.7 +/- 16.2 years. The prevalence rates of autoimmune thyroiditis and celiac disease were determined in all probands and in 100 of the 412 first-degree relatives. Control groups included 78 subjects age 14.9 +/- 10.4 years for the prevalence of autoimmune thyroiditis and 120,000 youth ages 16-17 years for the prevalence of celiac disease. Thyroiditis and celiac disease were diagnosed by abnormally high thyroid peroxidase (TPO), thyroglobulin (TG), antigliadin, and antiendomysial antibody titers. Celiac was confirmed by biopsy. A questionnaire was used to interview probands and relatives to determine the spectrum of autoimmune manifestations.

RESULTS

The prevalence of autoimmune thyroiditis determined by high TPO and/or TG titers was 27 and 25% for probands and relatives, respectively. These rates were higher than those for control subjects (P < 000.1). The prevalence of celiac disease among probands and screened relatives was 8.3 and 6%, respectively. These rates were higher than those for control subjects and the 312 family members interviewed only (0.1 and 0.3%, respectively; P < 0.0001). Interviews of participants revealed a wide range of associated autoimmune diseases. The risk of developing an autoimmune disease was higher (P < 0.001) in families with a proband who had an additional autoimmune manifestation.

CONCLUSIONS

Screening for autoimmune thyroiditis and celiac disease should be performed in patients with type 1 diabetes and their first-degree relatives, especially when the probands have an additional autoimmune manifestation.

Invertase, maltase, lactase, and peroxidase activities in duodenum of BB rats

The development of immune-mediated diabetes in BB rats may involve a defect of the gastrointestinal tract (GI), as suggested by increased gut permeability. This study aimed at measuring invertase, maltase, lactase, and peroxidase activities in the duodenum of diabetesprone BioBreeding (BBdp) rats and control BioBreeding rats (BBc) given free access to NIH-07 diet up to the time of killing at 60 66 d of age. After washing the entire small intestine, the duodenal mucosa was scraped off in the first 5-cm segment from the pylorus and frozen in distilled water. Invertase, maltase, and lactase activities were measured by monitoring the conversion of [U-(14)C]sucrose, [U-(14)C]maltose, and [D-[1-(14)C]glucose] lactose to radioactive hexoses, which were phosphorylated in the presence of adenosine triphosphatase and yeast hexokinase and then separated from their precursor by ion-exchange chromatography. Peroxidase activity was measured by a spectrophotometric procedure. In the BBdp rats, the activity of invertase, maltase, and lactase averaged, respectively, 70.2 +/- 4.4, 81.2 +/- 4.3, and 75.7 +/- 4.1% (n = 16 and p < 0.001 in all cases) of the control values found in BBc rats of the same sex. Inversely, after exclusion of two female BBc rats with abnormally high plasma D-glucose concentration, the activity of peroxidase in the BBdp rats averaged 157.4 +/- 20.0% (n = 16; p < 0.02) of the mean control value recorded in BBc rats of the same sex (100.0 +/- 9.3%; n = 14). These findings are compatible with the view that a proinflammatory state of the GI associated with compromise function may precede the occurrence of pancreatic insulitis in BBdp rats and, possibly, human subjects with type 1 diabetes.

Endocrinological disorders and celiac disease

Celiac disease is a permanent intolerance to dietary gluten. Its well known features are abdominal symptoms, malabsorption of nutrients, and small-bowel mucosal inflammation with villous atrophy, which recover on a gluten-free diet. Diagnosis is challenging in that patients often suffer from subtle, if any, symptoms. The risk of clinically silent celiac disease is increased in various autoimmune conditions. The endocrinologist, especially, should maintain high suspicion and alertness to celiac disease, which is to be found in 2-5% of patients with insulin-dependent diabetes mellitus or autoimmune thyroid disease. Patients with multiple endocrine disorders, Addison's disease, alopecia, or hypophysitis may also have concomitant celiac disease. Similar heredity and proneness to autoimmune conditions are considered to be explanations for these associations. A gluten-free diet is essential to prevent celiac complications such as anemia, osteoporosis, and infertility. The diet may also be beneficial in the treatment of the underlying endocrinological disease; prolonged gluten exposure may even contribute to the development of autoimmune diseases. The diagnosis of celiac disease requires endoscopic biopsy, but serological screening with antiendomysial and antitissue transglutaminase antibody assays is an easy method for preliminary case finding. Celiac disease will be increasingly detected provided the close association with autoimmune endocrinological diseases is recognized.

A longitudinal study of the effects of a gluten-free diet on glycemic control and weight gain in subjects with type 1 diabetes and celiac disease

OBJECTIVE

To describe the longitudinal growth characteristics and glycemic control in type 1 diabetic children diagnosed with celiac disease and started on a gluten-free diet (GFD).

RESEARCH DESIGN AND METHODS

Data on growth and glycemic control for 11 case subjects diagnosed with celiac disease (cd(+) group) and started on a GFD were collected prospectively, and two control subjects without celiac disease matched for age, sex, and duration of diabetes (cd(-) group) were selected for comparison.

RESULTS

In the period between diagnosis of type 1 diabetes and start of a GFD in the cd(+) compared with the cd(-) group, BMI standard deviation score (SDS) was lower (-0.2 vs. 0.7, P = 0.015), as was HbA(1c) (8.9 vs. 9.8%, P = 0.002). In a regression model the cd(+) group had lower BMI SDS (P < 0.001) and lower HbA(1c) (P = 0.04), independent of other variables. On a GFD, BMI SDS increased by 12 months in the cd(+) group and then was no different than the cd(-) group (1.1 vs. 1.0, P = 0.11), whereas HbA(1c) improved further within case subjects compared with pre-GFD (8.9 vs. 8.3%, P = 0.002). On a GFD, case subjects in contrast to control subjects showed no deterioration in HbA(1c) during the years of puberty (8.3 vs. 10.0%, P = 0.022)

CONCLUSIONS

In children with type 1 diabetes, untreated celiac disease resulted in lower BMI SDS and lower HbA(1c). Recovery of BMI SDS with a GFD was associated with further improvement in HbA(1c) as compared with pre-GFD, with no expected deterioration in glycemic control during puberty. These apparent clinical benefits need confirming by larger studies.

Elimination of dietary gluten does not reduce titers of type 1 diabetes-associated autoantibodies in high-risk subjects

OBJECTIVE

Removal of the dietary wheat protein gluten protects against autoimmune diabetes in animal models. Furthermore, elimination of dietary gluten reduces the frequency of type 1 diabetes in patients with celiac disease. Herein we test the hypothesis that gluten is the driving antigen for type 1 diabetes-associated islet autoimmunity.

RESEARCH DESIGN AND METHODS

Seven autoantibody-positive, first-degree relatives of patients with type 1 diabetes were placed on a gluten-free diet for 12 months followed by gluten reexposure for 12 months. Gliadin antibodies as well as the diabetes-related antibodies insulin autoantibody (IAA), GAD antibody (GADA), and tyrosin phosphatase IA2 antibody (IA-2A) were measured every 3 months; oral glucose tolerance tests were performed every 6 months. Changes in autoantibody titers were compared with those observed in a matched historical cohort.

RESULTS

A reduction in IgG gliadin antibody titers was observed during the gluten-free period, but titers of diabetes-associated autoantibodies changed independently of gluten exposure. Type 1 diabetes-associated islet autoantibody levels at the end of the gluten-free diet period were not significantly different from those before commencement of the diet (P = 0.2) or at the end of the gluten reexposure period (P = 0.4). Changes in individual subjects were identified, but no differences were noted between the gluten-free and the gluten re-exposure periods, and the changes were similar to those observed in the historical control cohort (P = 1.0). Major titer reductions (>50%) in the gluten-free period were observed in only one subject for all antibodies. Type 1 diabetes developed in this subject and in a second subject during the gluten reexposure period.

CONCLUSIONS

The findings do not support the hypothesis that gluten is a driving antigen in type 1 diabetes.

Type 1A diabetes mellitus-associated autoimmunity

Type 1A diabetes mellitus has become one of the most intensively studied autoimmune disorders, with characterized animal models and extensive prospective studies of the development of anti-islet autoimmunity. It is now possible to predict the development of type 1A diabetes mellitus, beginning with HLA-encoded genetic susceptibility, followed by the development of a series of anti-islet autoantibodies. Prediction primarily is based on the detection of multiple anti-islet autoantibodies reacting with cloned islet antigens. Multiple international workshops fostered the development of specific and sensitive radioassays for autoantibodies reacting with GAD65 (glutamic acid decarboxylase), ICA512 (also termed IA-2, a tyrosine phosphatase-like protein), and insulin. Similar high throughput radioassays have been applied using autoantigens for additional autoimmune disorders including celiac disease and Addison's disease. Relatives of patients with type 1A diabetes mellitus inherit susceptibility to express multiple autoantibodies, and a subset of autoantibody-positive individuals inherit susceptibility to progress to overt disease. This article reviews autoimmune disorders associated with type 1A diabetes mellitus.

Tissue transglutaminase-serology markers for coeliac disease

Serology markers of coeliac disease (CD) - antigliadin IgA/IgG antibodies (AGA/AGG) with purified alpha-gliadin, antiendomysium IgA antibodies (EmA) and anti-tissue transglutaminase (atTG) IgA/IgG antibodies--determined in 1451 serum samples, were analysed with respect to different screening algorithms. Determination of atTG using five ELISA methods was compared taking into account the impact of human recombinant antigen and IgG class of atTG. A subgroup of 119 patients undergoing small intestinal biopsy was used to calculate sensitivity and specificity of CD markers. The highest sensitivity (94%) was obtained for AGG, and the highest specificity (93.5%) was obtained for EmA. All coeliac disease patients were detected using the combination of all four CD markers, resulting in 100% sensitivity. CD and type 1 diabetes mellitus autoantigens were determined in 139 diabetic patients. The atTG IgA mean value (16.7 IU/ml) was higher in the antiglutamate dehydrogenase antibody (GAD)-positive subgroup, where at least one CD marker was positive in 83.6% subjects. In the GAD-negative subgroup atTG IgA was 8.73 lU/ml and at least one CD marker was positive in 57.4% subjects. atTG in IgA and IgG classes could be recommended as valuable serological markers of CD in the differential diagnosis of malabsorption as well as in various screening algorithms. ELISA determination of atTG with human antigen could increase the specificity, especially in patients with other autoimmune diseases.

Celiac disease-associated autoimmune endocrinopathies

Celiac disease (CD) is an autoimmune disorder induced by gluten intake in genetically susceptible individuals. It is characterized by the presence of serum antibodies to endomysium, reticulin, gliadin, and tissue transglutaminase. The incidence of CD in various autoimmune disorders is increased 10- to 30-fold in comparison to the general population, although in many cases CD is clinically asymptomatic or silent. The identification of such cases with CD is important since it may help in the control of type I diabetes or endocrine functions in general, as well as in the prevention of long-term complications of CD, such as lymphoma. It is believed that CD may predispose an individual to other autoimmune disorders such as type I diabetes, autoimmune thyroid, and other endocrine diseases and that gluten may be a possible trigger. The onset of type I diabetes at an early age in patients with CD, compared to non-CD, and the prevention or delay in onset of diabetes by gluten-free diet in genetically predisposed individuals substantiates this antigen trigger hypothesis. Early identification of CD patients in highly susceptible population may result in the treatment of subclinical CD and improved control of associated disorders.

The high prevalence of autoantibodies to tissue transglutaminase in first-degree relatives of patients with type 1 diabetes is not associated with islet autoimmunity

OBJECTIVE

To determine the extent of celiac autoimmunity in type 1 diabetic patients and the overlap between islet and celiac autoimmunity in their nondiabetic relatives.

RESEARCH DESIGN AND METHODS

IgA antibodies to tissue transglutaminase were determined in serum taken from 433 type 1 diabetic patients and 1,442 nondiabetic first-degree relatives. Samples with transglutaminase antibodies above the 97.5th percentile of 347 schoolchildren were also assayed for IgA anti-endomysial antibodies (EMAs). Markers of islet autoimmunity (islet cell antibodies and autoantibodies to insulin, glutamate decarboxylase. and protein tyrosine phosphatase IA-2) had previously been measured in all relatives.

RESULTS

In the absence of known celiac disease, the prevalence of transglutaminase antibody levels above the 97.5th percentile of the schoolchildren was 13.4% in diabetic patients and 7.0% in nondiabetic relatives. ENMAs were found in addition to transglutaminase antibodies in 2.6% of probands and in 1.9% of first-degree relatives, but none of the schoolchildren. Transglutaminase antibodies were found to persist in 10 of 30 patients and in 30 of 59 relatives with follow-up samples taken at least 2 years after the initial sample. Of 186 nondiabetic relatives with islet autoantibodies, only 10 also had transglutaminase antibodies.

CONCLUSIONS

We found a high prevalence of celiac autoimmunity in patients and first-degree relatives of children with type 1 diabetes, but we found limited overlap between islet and celiac autoimmunity in nondiabetic relatives. The high prevalence of celiac autoimmunity may be explained by shared genetic susceptibility and identifies a population within which screening for the disease may be justified.

Current approaches to diagnosis and treatment of celiac disease: an evolving spectrum

Celiac disease (CD) is a syndrome characterized by damage of the small intestinal mucosa caused by the gliadin fraction of wheat gluten and similar alcohol-soluble proteins (prolamines) of barley and rye in genetically susceptible subjects. The presence of gluten in these subjects leads to self-perpetuating mucosal damage, whereas elimination of gluten results in full mucosal recovery. The clinical manifestations of CD are protean in nature and vary markedly with the age of the patient, the duration and extent of disease, and the presence of extraintestinal pathologic conditions. In addition to the classical gastrointestinal form, a variety of other clinical manifestations of the disease have been described, including atypical and asymptomatic forms. Therefore, diagnosis of CD is extremely challenging and relies on a sensitive and specific algorithm that allows the identification of different manifestations of the disease. Serologic tests developed in the last decade provide a noninvasive tool to screen both individuals at risk for the disease and the general population. However, the current gold standard for the diagnosis of CD remains histologic confirmation of the intestinal damage in serologically positive individuals. The keystone treatment of CD patients is a lifelong elimination diet in which food products containing gluten are avoided.

Comparative analysis of organ-specific autoantibodies and celiac disease--associated antibodies in type 1 diabetic patients, their first-degree relatives, and healthy control subjects

OBJECTIVE

In type 1 diabetes the coexistence with other endocrine diseases and organ-specific autoantibodies has been frequently reported leading to the concept of autoimmune polyendocrine syndrome (APS). In addition, an association of type 1 diabetes with celiac disease has been described. These disorders share a similar genetic background, and first-degree relatives of type 1 diabetic patients may also be affected significantly. Screening for specific antibodies allows early diagnosis of these disorders.

RESEARCH DESIGN AND METHODS

In the present cross-sectional study, we analyzed sera from 197 recent-onset type 1 diabetic patients at the time of diagnosis, 882 first-degree relatives, and sera of 150 healthy control subjects for prevalence and co-occurence of the following antibodies (method): insulin autoantibodies (radioimmunoassay); GAD and IA-2 antibodies (radioligand assay); islet cell antibody, anti-adrenal cortex antibodies, and anti-gastric parietal cell antibodies (indirect immunofluorescence); anti-thyroglobulin and anti-thyroid peroxidase antibodies; and gliadin IgG/A and tissue-transglutaminase IgA (enzyme-linked immunosorbent assay).

RESULTS

The overall frequency of gastric patietal cell antibodies and adrenal antibodies did not differ significantly among groups. In contrast, type 1 diabetes-associated antibodies and thyroid antibodies were significantly more frequent both in recent-onset type 1 diabetic patients and in the group of first-degree relatives (P < 0.05). The prevalence of gliadin IgG/IgA and transglutaminase IgA was significantly higher in the group of recent-onset type 1 diabetic patients (P < 0.05), but the difference between first-degree relatives and control subjects did not reach statistical significance. Focusing on the coexistence of antibodies, the group of recentonset type 1 diabetic patients presented with 27.4% of the subjects testing antibody-positive-specific for two or more of the envisaged disorders (i.e., type 1 diabetes, autoimmune thyroiditis, and celiac disease) compared with 3.1% in the group of first-degree relatives and 0 of 150 in the control population (P < 0.05).

CONCLUSIONS

We conclude that, in an active case-finding strategy, recent-onset type 1 diabetic patients should be routinely screened at least for concomitant autoimmune thyroid disease and additionally for celiac disease. Screening in their first-degree relatives should include at a minimum the search for thyroid autoimmunity in addition to screening for pre-type 1 diabetes.