Autoantibody "subspecificity" in type 1 diabetes: risk for organ-specific autoimmunity clusters in distinct groups

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

OBJECTIVE

To determine the prevalence of celiac disease (CD) in children with type 1 diabetes mellitus (TIDM) in follow-up in a Tertiary Care Referral Centre in Western India and to describe the clinical features indicative of CD in screened patients of TIDM.

STUDY DESIGN

In this single center observational cross-sectional study, 71 children who were diagnosed with TIDM were subjected to screening for CD with tissue transglutaminase antibody testing. Those who tested positive were offered intestinal biopsy for the confirmation of diagnosis. Clinical profiles of both groups of patients were compared and manifestations of CD were delineated.

RESULTS

The study revealed the prevalence of CD (based on serology) in children with Type 1 diabetes as 15.49%. The prevalence of biopsy-confirmed CD was 7.04%. Of the diagnosed CD patients, one-third were symptomatic at the time of screening while the majority was asymptomatic. The major clinical features indicative of CD were intestinal symptoms, anemia, rickets, and short stature. Autoimmune thyroid disease was prevalent in 29.6% of the patients with TIDM followed by CD.

CONCLUSIONS

The high prevalence of CD in children with Type 1 diabetes emphasizes the need for routine screening programs to be in place for these high-risk populations. The clinical profile of patients with CD further elaborates the indicators of CD and the need to screen for them.

Genetics of Autoimmune Thyroiditis in Type 1 Diabetes Reveals a Novel Association With DPB1*0201: Data From the Type 1 Diabetes Genetics Consortium

BACKGROUND

Autoimmune thyroiditis occurs in 10-25% of patients with type 1 diabetes (T1D). Most of these patients are also positive for thyroid peroxidase (TPO) antibodies. Thyroid dysfunction complicates T1D metabolic control and is a component of the autoimmune polyglandular syndrome (APS, type 2 or 3). Previous studies of isolated T1D and of T1D combined with other autoimmune disorders showed genetic susceptibility for alleles in HLA-DQB1 and -DRB1 and also CTLA4 and PTPN22.

RESEARCH DESIGN AND METHODS

We analyzed the Type 1 Diabetes Genetics Consortium Autoantibody Workshop data by differentiating those T1D probands with and without TPO antibodies or thyroid disease with respect to polymorphisms in HLA, CTLA4, INS, PTPN22, and VDR, taking into account the ethnic origin. Genotype and clinical/immunogenic phenotype data were analyzed by gene counting methods and logistic regression analysis.

RESULTS

The presence of TPO antibodies (25.2%) and thyroid disease (8.4%) was associated with older age, female sex, and presence of other autoantibodies (GAD65, ATPase, 21-OH) (all P<0.001). The highest prevalence was in patients of Hispanic ancestry (31%) and the lowest in those of African ancestry (8%). In T1D non-Hispanic whites, HLA-DRB1*0101 is significantly (P<0.0001) less frequent in TPO-positive than in TPO-negative individuals, whereas HLA-DRB1*0404, -DQB1*0301, and -DPB1*0201 are significantly (P<0.0001) more frequent. Subjects with a high titer of TPO autoantibodies and with thyroid disease were associated with female sex and older age and negatively associated with DRB1*0401-DQB1*0302 (P<0.0001). No significant differences were observed for an association of TPO positivity or thyroid disease with single nucleotide polymorphisms in the INS, CTLA4, or VDR loci, with nominal significance (P=0.01) for PTPN22 R620W variant.

CONCLUSIONS

Thyroid autoimmunity is highly prevalent in T1D patients of non-Hispanic white, Asian, or Hispanic origin. The strongest disease risk is conferred by female sex and older age. This risk is modulated by HLA-DRB1 and HLA-DPB1 loci. The immunogenetic profile for T1D with thyroid autoimmunity may identify distinct pathways regulating polyglandular autoimmunity and disease.

Italian Association of Clinical Endocrinologists (AME) & Italian Association of Clinical Diabetologists (AMD) Position Statement : Diabetes mellitus and thyroid disorders: recommendations for clinical practice

Thyroid disease and diabetes mellitus, the most common disorders in endocrine practice, are not infrequently associated in the same subject. An altered thyroid function may affect glucose tolerance and worsen metabolic control in patients with diabetes. Thyrotoxicosis increases the risk of hyperglycemic emergencies, while a clinically relevant hypothyroidism may have a detrimental effect on glycemic control in diabetic patients. The association of alterations in thyroid function with diabetes mellitus may adversely affect the risk of cardiovascular and microvascular complications resulting from diabetes. Moreover, the treatments used for both diabetes and thyroid disease, respectively, can impact one other. Finally, multinodular goiter, but not thyroid carcinoma, was shown to be more prevalent in type 2 diabetes mellitus. Aim of the present Position Statement is to focus on the evidence concerning the association of thyroid disease and diabetes mellitus and to provide some practical suggestions for an updated clinical management.

Clinical relevance and cost-effectiveness of HLA genotyping in children with Type 1 diabetes mellitus in screening for coeliac disease in the Netherlands

AIMS

To investigate the clinical relevance and cost-effectiveness of human leukocyte antigen (HLA)-genotyping in the Netherlands as a screening tool for the development of coeliac disease in children with Type 1 diabetes mellitus.

METHODS

A retrospective analysis was performed in 110 children with Type 1 diabetes mellitus diagnosed between January 1996 and January 2013. All children were screened for coeliac disease using coeliac disease-specific antibodies and HLA genotyping was performed in all children.

RESULTS

One hundred and ten children were screened for coeliac disease, and coeliac disease could be confirmed in seven. Eighty-six per cent of the children with Type 1 diabetes mellitus had one of the variants of HLA-DQ2.5 and DQ8. HLA genotypes observed in children with Type 1 diabetes mellitus children and coeliac disease were heterozygote DQ2.5, homozygote DQ2.5 and heterozygote DQ2.5/DQ8. HLA genotyping in coeliac disease screening in children with Type 1 diabetes mellitus is more expensive than screening for coeliac disease with antibodies alone (€326 vs. €182 per child).

CONCLUSIONS

The risk of coeliac disease development in children with Type 1 diabetes mellitus is increased when they are heterozygote DQ2.5/DQ8, homozygote or heterozygote DQ2.5. The implementation of HLA genotyping as a first-line screening tool has to be reconsidered because it is not distinctive or cost-effective.

Loss of anergic B cells in prediabetic and new-onset type 1 diabetic patients

Although dogma predicts that under normal circumstances, potentially offensive autoreactive cells are silenced by mechanisms of immune tolerance, islet antigen-reactive B lymphocytes are known to play a crucial role in the development of autoimmunity in type 1 diabetes (T1D). Thus, participation of these cells in T1D may reflect escape from silencing mechanisms. Consistent with this concept, we found that in healthy subjects, high-affinity insulin-binding B cells occur exclusively in the anergic naive IgD(+), IgM(-) B-cell (BND) compartment. Antigen receptors expressed by these cells are polyreactive and have N-region additions, Vh usage, and charged complementarity-determining region 3 consistent with autoreactivity. Consistent with a potential early role in autoimmunity, these high-affinity insulin-binding B cells are absent from the anergic compartment of some first-degree relatives and all prediabetic and new-onset (<1 year) T1D patients tested, but return to normal levels in individuals diabetic for >1 year. Interestingly, these changes were correlated by transient loss of the entire BND compartment. These findings suggest that environmental events such as infection or injury may, by disrupting B-cell anergy, dispose individuals toward autoimmunity, the precise nature of which is specified by genetic risk factors, such as HLA alleles.

Allelic variant in CTLA4 is associated with thyroid failure and faster β-cell exhaustion in latent autoimmune diabetes in adults

BACKGROUND

The aim of the study was to investigate the role of the cytotoxic T-lymphocyte-associated protein 4 (CTLA4) G6230A variant on the susceptibility of latent autoimmune diabetes in adults (LADA) as a whole and in the subset of patients who share autoimmune thyroid disease (AITD).

METHODS

The study included 202 LADA, 1373 patients with early onset type 1 diabetes (T1D), 130 patients with late-onset T1D, 188 patients with non-autoimmune diabetes and 1904 healthy controls. Thyrotropin (thyrotropin-stimulating hormone; TSH) and antibodies against thyroid peroxidase were analyzed in all patients. The CTLA4 G6230A variant was assessed in LADA, early and late-onset T1D patients as well as in the controls.

RESULTS

The frequency of CTLA4 G alleles and genotypes in LADA patients did not differ significantly from that in the other groups, regardless of its association with AITD. We found an increased frequency of G allele-containing genotypes within LADA patients who had higher TSH compared with those with normal TSH (P = 0.002). Moreover, LADA patients carrying G allele-containing genotypes were more likely to require insulin therapy within 4 years of diagnosis (P = 0.002).

CONCLUSIONS

The G6230A CTLA4 variant does not confer susceptibility to LADA in Sardinian patients even when associated with AITD. However, it helps identify a particular subset of LADA patients with more clinically severe disease, both for thyroid dysfunction and diabetes.

[Intercurrent and autoimmune processes in type 1 diabetes mellitus]

AIM

To estimate the prevalence of autoantibodies pathognomonic for autoimmune diseases of connective tissue and liver in patients with type 1 diabetes mellitus (DM1) and to study their clinical features in patients positive for these indicators.

MATERIAL AND METHODS

A total of 84 patients (39 men and 45 women) with DM1 divided into 2 groups were examined. Biochemical, immunological, and instrumental examinations were performed.

RESULTS

There was a high prevalence of markers of autoimmune diseases of connective tissue and liver in patients with DM1 and that of autoantibodies in those without its clinical symptoms or signs according to instrumental findings.

CONCLUSION

The findings may suggest that patients with DM1 have a higher risk of concomitant autoimmune diseases with a probability of their asymptomatic course.

Increased risk for vitamin d deficiency in obese children with both celiac disease and type 1 diabetes

Background. It is unknown whether the coexistence of type 1 diabetes (T1D) and celiac disease (CD) increases the risk for vitamin D deficiency. Aims. To determine the vitamin D status and the risk for vitamin D deficiency in prepubertal children with both T1D and CD compared to controls, TID, and CD. Subjects and Methods. Characteristics of 62 prepubertal children of age 2–13 y with either CD + T1D (n = 22, 9.9 ± 3.1 y), CD only (n = 18, 8.9 ± 3.3 y), or T1D only (n = 22, 10.1 ± 2.8 y) were compared to 49 controls of the age of 8.0 ± 2.6 years. Vitamin D deficiency was defined as 25(OH)D < 50 nmol/L, overweight as BMI of >85th but <95th percentile, and obesity as BMI > 95th percentile. Results. The 4 groups had no difference in 25(OH)D (ANOVA P = 0.123) before stratification into normal-weight versus overweight/obese subtypes. Following stratification, 25(OH)D differed significantly between the subgroups (F_(3,98) = 10.109, ANOVA P < 0.001). Post-hoc analysis showed a significantly lower 25(OH)D in the overweight/obese CD + T1D compared to the overweight/obese controls (P = 0.039) and the overweight/obese CD (P = 0.003). Subjects with CD + T1D were 3 times more likely to be vitamin D deficient (OR = 3.1 [0.8–11.9], P = 0.098), compared to controls. Conclusions. The coexistence of T1D and CD in overweight/obese prepubertal children may be associated with lower vitamin D concentration.

Newly diagnosed T1 diabetes presenting with hypoglycemia due to simultaneous co-existence of Addison disease

Type 1 diabetes mellitus (TIDM) classically presents with symptomatic hyperglycemia and many patients develop diabetic ketoacidosis prior to their diagnosis. However, non-classical presentation or co-presentation with associated diseases may delay diagnosis or lead to challenges in acute, clinical management. An 18-yr-old girl presented to hospital with severe, symptomatic hypoglycemia. Clinical history and serum electrolyte concentrations suggested a diagnosis of adrenal insufficiency. She remained hypoglycemic until glucocorticoid replacement was commenced, at which point she developed persistent hyperglycemia requiring insulin therapy. Subsequent follow up confirmed the diagnosis of Addison's disease (AD), the treatment of which unmasked co-existing type 1 diabetes. Autoimmune diseases often cluster together in affected patients and first-degree relatives. Approximately 1 in 200 patients with T1DM develop AD. However, months or more commonly years usually elapse between the presentation of different autoimmune conditions. The co-diagnosis T1DM and AD in the acute setting is rare. Moreover, the first presentation of T1DM with severe hypoglycemia is even more exceptional. This case highlights the need for vigilance during the acute, emergency management of patients with autoimmune conditions and, in particular, to consider the possibility of concurrent antibody-mediated diseases which may need to be addressed during resuscitation.

Are zinc transporter type 8 antibodies a marker of autoimmune thyroiditis in non-obese adults with new-onset diabetes?

OBJECTIVE

The diagnosis of autoimmune diabetes in non-obese adults is based on the detection of glutamic acid decarboxylase autoantibodies (GADA), islet cell antibodies (ICA) and antibodies to tyrosine phosphatase (IA-2A). Zinc transporter 8 (ZnT8) has been identified as a new autoantigen in patients with type 1 diabetes mellitus. The coincidence of autoimmune thyroiditis (AITD) with diabetes is common; therefore, screening of TSH and thyroid peroxidase antibodies (ATPO) is recommended during the diagnosis of diabetes. In this study, we determined whether the occurrence of islet autoantibodies is associated with a positive titre of ATPO in newly diagnosed adult-onset autoimmune diabetic patients.

DESIGN AND METHODS

THE STUDY INVOLVED 80 NON-OBESE ADULTS AGED 44 (INTERQUARTILE RANGE (IQR): 37-51) years with a BMI of 24.0 (IQR: 22.2-26.0) kg/m(2) and new-onset diabetes. The markers of autoimmune diabetes (GADA, ICA, IA-2A and ZnT8A), TSH and thyroid peroxidase antibodies (ATPO) were evaluated.

RESULTS

IN THE STUDY POPULATION, 70% (N=56) OF THE SUBJECTS WERE POSITIVE FOR AT LEAST ONE OF THE FOUR ASSESSED MARKERS OF AUTOIMMUNE DIABETES (83.9% GADA, 62.5% ICA, 42.8% IA-2A AND 33% ZNT8A) AND 37.5% OF THE SUBJECTS WERE POSITIVE FOR ATPO. THE ZNT8A-POSITIVE SUBJECTS HAD HIGHER ATPO TITRES THAN THE ZNT8A-NEGATIVE SUBJECTS (172.7 (IQR: 0.36-410.4) vs 92.4 (IQR: 0-23.7) IU/ml, P=0.001). Based on the assessed islet autoantibodies, the occurrence of positive ZnT8A and GADA was found to be related to a positive titre of ATPO using logistic regression (OR=5.48, 95% CI: 1.65-18.14, P=0.006 and OR=3.42, 95% CI: 1.09-10.71, P=0.03 respectively).

CONCLUSIONS

In non-obese adults with new-onset diabetes, the presence of GADA and especially ZnT8 autoantibodies increases the risk of AITD.

Autoimmune hepatitis related autoantibodies in children with type 1 diabetes

BACKGROUND AND OBJECTIVES

The frequency of Type 1 diabetes (T1D)-related autoantibodies was determined in children with autoimmune hepatitis. However, the incidence of autoimmune hepatitis related autoantibodies in children with T1D has been poorly investigated. The aim of the present cross sectional prospective study was to determine the occurrence of autoimmune hepatitis-related autoantibodies in children with T1D.

METHODS

Children with T1D following in diabetic clinic in our center were screened for existence of liver related autoantibodies from November 2010 to November 2011. The patients' sera were analyzed for the existence of autoantibodies such as anti-nuclear antibody, anti-smooth muscle antibody, and anti-Liver Kidney microsomal antibody, using enzyme linked immunoassay and indirect immunofluorescence methods. A titer of anti-nuclear antibody ≥1/40 was considered positive and titer of < 1/40 was considered negative. Anti-liver kidney microsomal antibody titer of < 3 U/ml was considered negative, 3 - 5 U/ml borderlines, and > 5 U/ml was considered positive.

RESULTS

106 children with T1D have been examined over a one-year period: age ranges between 8 months to 15.5 years, sixty two patients were females. Autoantibody screen revealed a girl with positive anti-liver kidney microsomal antibody (1%) and 8 children had positive anti-nuclear antibody (7.5%), without clinical, biochemical or radiologic evidence of liver disease. None of the patients had positive smooth muscle antibody.

IN CONCLUSION

Anti-liver kidney microsomal antibody is rarely found in sera of children with T1D; the clinical significance of which is unknown.

A Study of Autoimmune Polyglandular Syndrome (APS) in Patients with Type1 Diabetes Mellitus (T1DM) Followed Up at a Teritiary Care Hospital

BACKGROUND

Type1 diabetes mellitus (T1DM) results from auto- immune destruction of insulin-producing β cells and is characterized by the presence of insulitis and β-cell autoantibodies. Up to one third of patients develop an autoimmune polyglandular syndrome (APS). Presence of other autoimmune disorders in patients with T1DM has been associated with increased morbidity and mortality. Hypoglycemia resulting from concurrent hypothyroidism or adrenal crisis can be dangerous; starting replacement therapy for hypothyroidism may result in adrenal crisis if background hypocortisolism is not recognized. Early detection of antibodies and latent organ-specific dysfunction is advocated to alert physicians to take appropriate action in order to prevent full-blown disease.

AIMS

The objectives of this study were to assess the concurrence of various autoimmune disorders in patients with T1DM, to review the concept and detect the overt forms of Autoimmune Thyroid Disease (AITD), Addison's Disease (AD), Vitamin B 12, vitiligo in T1DM and to find their correlation according to age and sex of the patients.

METHODS

It is a retrospective study where medical records between January 2007-June 2010 of all the patients diagnosed with T1DM, followed up at Department of Endocrinology were reviewed to find out the presence of (AD), AITD, vitiligo, Vitamin B12 deficiency and Primary Gonadal Failure, which were diagnosed clinically with available investigational procedures.

RESULTS

A total of 100 cases of T1DM were evaluated during the present study. The age group of patients ranged from 8 to 40 years, with the average being 21.56 years. 64% of the patients were males and the rest were females. 29 % of T1DM subjects had AITD (Hashimoto's or Graves'disease), 5% were diagnosed with Vitamin B12 deficiency, 4% had AD, and 6% showed Vitiligo. 28 % had family history of autoimmune endocrinopathy.

CONCLUSION

The commonest autoimmune disorder associated with T1DM found in our study was AITD. Because genetic/ autoantibodies testing is not a feasible option, it is important to screen them with best available laboratory facilities and clinical assessment in view of high prevalence of associated autoimmune conditions.

Thyroid autoimmunity in Type 1 diabetes: systematic review and meta-analysis

AIMS

To review the incidence and evidence for screening for thyroid autoimmunity and thyroid dysfunction in Type 1 diabetes.

METHODS

Systematic review and meta-analysis. Inclusion criteria were prospective cohort studies screening for thyroid autoimmunity and/or dysfunction (defined as an abnormal thyroid-stimulating hormone level) in Type 1 diabetes. Exclusion criteria included pregnancy and thyroid dysfunction before diabetes onset. Outcomes examined were: incidence of thyroid autoimmunity and/or dysfunction; association between thyroid autoimmunity and dysfunction; and cost-effectiveness. Data sources were MEDLINE, EMBASE, the Cochrane Library, manual searching and contact with authors, with limitations to English language and human studies. Meta-analysis was performed using random effects models.

RESULTS

We identified 14 eligible studies, involving 2972 young people and 789 adults with Type 1 diabetes. Follow-up ranged from 1-18 years. None of the studies were of good methodological quality (Newcastle Ottowa Scale score > 7). The incidence of thyroid dysfunction (11 studies) ranged from 27 (95% CI 15-45) to 246 (95% CI 118-453) per 10 000 patient-years and thyroid autoimmunity (four studies) from 13 (95% CI 0.3-71) to 326 (95% CI 194-510). The risk of thyroid dysfunction was higher in those with thyroid autoimmunity: summary risk ratio 25 (95% CI 9-71) and was higher in children (49, 95% CI 16-150) compared with adults (7, 95% CI 3-13). No studies examined cost-effectiveness of screening.

CONCLUSIONS

There is a markedly increased risk of thyroid dysfunction in people with Type 1 diabetes and thyroid autoimmunity. The optimal method or frequency of screening could not be determined from available data. Future studies should examine whether screening improves clinical outcomes in this population.

Sequential elevation of autoantibodies to thyroglobulin and glutamic acid decarboxylase in type 1 diabetes

We have previously reported the high levels of glutamic acid decarboxylase 65 autoantibodies (GAD65A) in patients with type 1 diabetes and autoimmune thyroid disease. Here we describe a 32-year-old Japanese female with a thirteen-year history of type 1 diabetes whose levels of GAD65A were elevated just after the emergence of anti-thyroid autoimmunity. At 19 years of age, she developed diabetic ketoacidosis and was diagnosed with type 1 diabetes. She had GAD65A, insulinoma-associated antigen-2 autoantibodies (IA-2A), and zinc transporter-8 autoantibodies (ZnT8A), but was negative for antibodies to thyroid peroxidase (TPOAb) and thyroglobulin (TGAb) at disease onset. ZnT8A and IA-2A turned negative 2-3 years after the onset, whereas GAD65A were persistently positive at lower level (approximately 40 U/mL). However, just after the emergence of TGAb at disease duration of 12.5 years, GAD65A levels were reelevated up to 5717 U/mL in the absence of ZnT8A and IA-2A. Her thyroid function was normal and TPOAb were consistently negative. She has a HLA-DRB1*03:01/*04:01-DQB1*02:01/*03:02 genotype. Persistent positivity for GAD65A might be associated with increased risk to develop anti-thyroid autoimmunity.

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.

Thyroid autoimmunity in relation to islet autoantibodies and HLA-DQ genotype in newly diagnosed type 1 diabetes in children and adolescents

AIMS/HYPOTHESIS

The aim of this work was to investigate, in children newly diagnosed with type 1 diabetes: (1) the prevalence of autoantibodies against thyroid peroxidase (TPOAb) and thyroglobulin (TGAb); and (2) the association between TPOAb, TGAb or both, with either islet autoantibodies or HLA-DQ genes.

METHODS

Blood samples from 2,433 children newly diagnosed with type 1 diabetes were analysed for TPOAb and TGAb in addition to autoantibodies against arginine zinc transporter 8 (ZnT8RA), tryptophan zinc transporter 8 (ZnT8WA), glutamine zinc transporter 8 (ZnT8QA), glutamic acid decarboxylase (GADA), insulin (IAA), insulinoma-associated protein-2 (IA-2A), HLA-DQA-B1 genotypes, thyroid-stimulating hormone (TSH) and free thyroxine (T4).

RESULTS

At type 1 diabetes diagnosis, 12% of the children had thyroid autoantibodies (60% were girls; p < 0.0001). GADA was positively associated with TPOAb (p < 0.001) and with TGAb (p < 0.001). In addition, ZnT8A was associated with both TPOAb (p = 0.039) and TGAb (p = 0.015). DQB1*05:01 in any genotype was negatively associated with TPOAb (OR 0.55, 95% CI 0.37, 0.83, p value corrected for multiple comparisons (p c) = 0.012) and possibly with TGAb (OR 0.55, 95% CI 0.35, 0.87, p c = 0.07). Thyroid autoimmunity in children newly diagnosed with type 1 diabetes was rarely (0.45%) associated with onset of clinical thyroid disease based on TSH and free T4.

CONCLUSIONS/INTERPRETATION

GADA and ZnT8A increased the risk for thyroid autoimmunity at the time of clinical diagnosis of type 1 diabetes, while HLA-DQB1*05:01 reduced the risk. However, the associations between thyroid autoimmunity and HLA-DQ genotype were weak and did not fully explain the co-occurrence of islet and thyroid autoimmunity.

Celiac disease and autoimmune-associated conditions

Celiac disease (CD) is frequently accompanied by a variety of extradigestive manifestations, thus making it a systemic disease rather than a disease limited to the gastrointestinal tract. This is primarily explained by the fact that CD belongs to the group of autoimmune diseases. The only one with a known etiology is related to a permanent intolerance to gluten. Remarkable breakthroughs have been achieved in the last decades, due to a greater interest in the diagnosis of atypical and asymptomatic patients, which are more frequent in adults. The known presence of several associated diseases provides guidance in the search of oligosymptomatic cases as well as studies performed in relatives of patients with CD. The causes for the onset and manifestation of associated diseases are diverse; some share a similar genetic base, like type 1 diabetes mellitus (T1D); others share pathogenic mechanisms, and yet, others are of unknown nature. General practitioners and other specialists must remember that CD may debut with extraintestinal manifestations, and associated illnesses may appear both at the time of diagnosis and throughout the evolution of the disease. The implementation of a gluten-free diet (GFD) improves the overall clinical course and influences the evolution of the associated diseases. In some cases, such as iron deficiency anemia, the GFD contributes to its disappearance. In other disorders, like T1D, this allows a better control of the disease. In several other complications and/or associated diseases, an adequate adherence to a GFD may slow down their evolution, especially if implemented during an early stage.

The next big idea

George S. Eisenbarth will remain in our memories as a brilliant scientist and great collaborator. His quest to discover the cause and prevention of type 1 (autoimmune) diabetes started from building predictive models based on immunogenetic markers. Despite his tremendous contributions to our understanding of the natural history of pre-type 1 diabetes and potential mechanisms, George left us with several big questions to answer before his quest is completed.

The Relationship between Type 2 Diabetes Mellitus and Related Thyroid Diseases

Type 2 diabetes mellitus (T2DM) has an intersecting underlying pathology with thyroid dysfunction. The literature is punctuated with evidence indicating a contribution of abnormalities of thyroid hormones to type 2 DM. The most probable mechanism leading to T2DM in thyroid dysfunction could be attributed to perturbed genetic expression of a constellation of genes along with physiological aberrations leading to impaired glucose utilization and disposal in muscles, overproduction of hepatic glucose output, and enhanced absorption of splanchnic glucose. These factors contribute to insulin resistance. Insulin resistance is also associated with thyroid dysfunction. Hyper- and hypothyroidism have been associated with insulin resistance which has been reported to be the major cause of impaired glucose metabolism in T2DM. The state-of-art evidence suggests a pivotal role of insulin resistance in underlining the relation between T2DM and thyroid dysfunction. A plethora of preclinical, molecular, and clinical studies have evidenced an undeniable role of thyroid malfunctioning as a comorbid disorder of T2DM. It has been investigated that specifically designed thyroid hormone analogues can be looked upon as the potential therapeutic strategies to alleviate diabetes, obesity, and atherosclerosis. These molecules are in final stages of preclinical and clinical evaluation and may pave the way to unveil a distinct class of drugs to treat metabolic disorders.

Type 1 diabetes in pre-school children--long-term metabolic control, associated autoimmunity and complications

AIMS

To identify clinical characteristics and co-morbidity rates of children diagnosed with Type 1 diabetes mellitus at younger than 6 years of age.

METHODS

Data were obtained from a retrospective chart review of 103 patients diagnosed with Type 1 diabetes at younger than 6 years (study group) and 220 patients at older than 6 years (comparison group). Measures of glycaemic control and occurrence of co-morbidities (coeliac disease, autoimmune thyroid disease, hypertension, nephropathy and retinopathy) were compared.

RESULTS

The mean follow-up period was more than 8 years. For the study group, mean HbA(1c) levels ranged from 64 mmol/mol to 66 mmol/mol (8.0-8.2%) until age 10 years, and then rose to 73 mmol/mol (8.8%). The HbA(1c) levels were higher in the study than in the comparison group for comparable ages (P = 0.003). After adjustment for duration of diabetes this difference was not significant. The overall rate of severe hypoglycaemic events was greater in the study group than in the comparison group (P = 0.03). Kaplan-Meier diagnosis rates of celiac disease, 10 years after Type 1 diabetes diagnosis, were 14.4% and 4.2% in the study and comparison groups, respectively (P log-rank = 0.03). There were no differences in rates of autoimmune thyroid disease, hypertension, nephropathy or retinopathy.

CONCLUSIONS

Children diagnosed with Type 1 diabetes before the age of 6 years were in greater risk of developing celiac disease, compared with children diagnosed after the age of 6 years. For children diagnosed with Type 1 diabetes aged under 6 years, good metabolic control was achievable until age 10 years, after which it deteriorated. Higher HbA(1c) levels observed in children diagnosed before the age of 6 years were associated with longer duration of disease.

Extrapancreatic autoantibody profiles in type I diabetes

Type I diabetes (T1D) is an autoimmune disease characterized by destruction of insulin-producing β-cells in the pancreas. Although several islet cell autoantigens are known, the breadth and spectrum of autoantibody targets has not been fully explored. Here the luciferase immunoprecipitation systems (LIPS) antibody profiling technology was used to study islet and other organ-specific autoantibody responses in parallel. Examination of an initial cohort of 93 controls and 50 T1D subjects revealed that 16% of the diabetic subjects showed anti-gastric ATPase autoantibodies which did not correlate with autoantibodies against GAD65, IA2, or IA2-β. A more detailed study of a second cohort with 18 potential autoantibody targets revealed marked heterogeneity in autoantibody responses against islet cell autoantigens including two polymorphic variants of ZnT8. A subset of T1D subjects exhibited autoantibodies against several organ-specific targets including gastric ATPase (11%), thyroid peroxidase (14%), and anti-IgA autoantibodies against tissue transglutaminase (12%). Although a few T1D subjects showed autoantibodies against a lung-associated protein KCNRG (6%) and S100-β (8%), no statistically significant autoantibodies were detected against several cytokines. Analysis of the overall autoantibody profiles using a heatmap revealed two major subgroups of approximately similar numbers, consisting of T1D subjects with and without organ-specific autoantibodies. Within the organ-specific subgroup, there was minimal overlap among anti-gastric ATPase, anti-thyroid peroxidase, and anti-transglutaminase seropositivity, and these autoantibodies did not correlate with islet cell autoantibodies. Examination of a third cohort, comprising prospectively collected longitudinal samples from high-risk individuals, revealed that anti-gastric ATPase autoantibodies were present in several individuals prior to detection of islet autoantibodies and before clinical onset of T1D. Taken together, these results suggest that autoantibody portraits derived from islet and organ-specific targets will likely be useful for enhancing the clinical management of T1D.

Immunological comorbity in coeliac disease: associations, risk factors and clinical implications

PURPOSE

Coeliac disease is frequently associated with other immunomediated diseases. Our aim was to identify immunological comorbidities and possible risk factors for their development in coeliac patients.

METHODS

We recruited a cohort of 1,015 coeliac patients followed from 0 to 46 years in a single tertiary referral centre. Data were collected from the yearly scheduled clinical and serological evaluations. Possible risk factors such as demographic parameters, type of symptomatic presentation, gluten exposure, gluten-free diet compliance and family history were all evaluated. Subjects (848,606) from the regional health registry were investigated as controls.

RESULTS

The prevalence of immunomediated diseases was higher in patients with coeliac disease compared to the registry population (23 % vs 0.4 %, p < 0.001). Diagnosis during paediatric age represented a risk factor for the presence of at least an immunomediated disease (hazard ratio = 1.62, 95 % confidence interval 1.15-2.29, p = 0.0061). Type of presentation and dietetic compliance did not represent risk factors. Long-standing gluten exposure reduced the risk of developing immunomediated diseases in coeliac subjects (hazard ratio for 1 year longer exposure 0.23, 95 % confidence interval 0.16-0.33, p < 0.0001). A familiar background characterized by the presence of immunological disorders was not a risk factor, although 419 (13 %) first degree relatives of coeliac patients out of 3,195 had an immunomediated disease.

CONCLUSIONS

Our study suggests the need to investigate coeliac patients for other associated immunomediated diseases, independently of sex, gluten exposure and compliance to therapy; also subjects diagnosed in paediatric age should be carefully screened during follow up.

Clinical profile of coexisting conditions in type 1 diabetes mellitus patients

AIMS

Type 1 diabetes mellitus (T1DM) is associated with various genetic and autoimmune diseases implicated in its etiopathogenesis. We hereby profile the clinical association of such diseases among patients from our center.

METHODS

Consecutive patients of T1DM presenting to department of Endocrinology from May 1997 to December 2011 were retrospectively analyzed in context of associated clinical profile.

RESULTS

Among 260 patients diagnosed as T1DM, 21 (8%) had hypothyroidism, 4 (1.5%) had hyperthyroidism and 2 (0.7%) had primary adrenal insufficiency. Eighteen patients (7%) had celiac disease, 9 (3.5%) had Turner's syndrome, 5 patients (1.9%) had Klinefelter's syndrome, whereas Down's syndrome and Noonan's syndrome was present in 2 and 1 patients (0.7%) respectively. One patient had Wolframs' syndrome and 1 patients had myasthenia gravis. Systemic lupus erythematosus and rheumatoid arthritis were present in 3 and 1 patients respectively. Total of 5 patients with cerebral palsy, 4 cases with deaf mutism, 4 cases with acute psychosis and 16 patients with depression were noted. Mean age of study patients was 20.8±9.8 years (range, 3-23 years).

CONCLUSION

Various conditions including genetic (Down, Turner, Noonan, and Klinefelter's), autoimmune (thyroid and adrenal disorders, myasthenia gravis, SLE, rheumatoid arthritis) and central nervous system diseases were the associated diseases encountered in our patients. Routine screening is required for early diagnosis and treatment of associated co morbidities.

Thyroid-related autoantibodies in Tunisian patients with type 1 diabetes

AIM

To evaluate, retrospectively, the frequency of antithyroid antibodies (ATA) in patients with type 1 diabetes (T1D).

MATERIALS AND METHODS

Antithyroperoxidase antibodies (TPO-Ab), antithyroglobulin antibodies (TG-Ab), and antithyroid-stimulating hormone receptor antibodies (TSHR-Ab) were determined by enzyme-linked immunosorbent assay. Sera of 312 patients (166 children and 146 adults) with T1D were analyzed. Sera of 276 healthy subjects (87 children and 189 blood donors) served as controls.

RESULTS

Out of 312 patients with T1D, 44 (14%) had ATA (TPO-Ab or TG-Ab or TSHR-Ab). The frequency of ATA in patients with T1D was significantly higher than in the control group (14% vs. 2.8%; p<10(-5)). ATA were significantly more frequent in adult patients with T1D than in the blood donor group (20% vs. 1.6%; p<10(-8)). The frequency of ATA in adult patients was significantly higher than in pediatric patients (20% vs. 9%; p=0.006). The frequency of TPO-Ab and TG-Ab was significantly higher in patients with T1D than in the control group (13.5% vs. 2%; p<10(-8) and 7% vs. 2.2%, p=0.008), respectively. Out of 312 patients with T1D, only one had TSHR-Ab. The simultaneous presence of three autoantibodies was found in one patient with T1D.

CONCLUSION

ATA were frequent in patients with T1D. Serological screening of autoimmune thyroid disease is suggested in patients with T1D.

Origin and plasticity of MHC I-associated self peptides

Endogenous peptides presented by MHC I molecules represent the essence of self for CD8 T lymphocytes. These MHC I peptides (MIPs) regulate all key events that occur during the lifetime of CD8 T cells. CD8 T cells are selected on self-MIPs, sustained by self-MIPs, and activated in the presence of self-MIPs. Recently, large-scale mass spectrometry studies have revealed that the self-MIP repertoire is more complex and plastic than previously anticipated. The composition of the self-MIP repertoire varies from one cell type to another and can be perturbed by cell-intrinsic and -extrinsic factors including dysregulation of cellular metabolism and infection. The complexity and plasticity of the self-MIP repertoire represent a major challenge for the maintenance of self tolerance and can have pervasive effects on the global functioning of the immune system.

Prevention of type 1 diabetes

Prevention of loss of b cells in type 1 diabetes is a major goal of current research. Knowledge of the genetic susceptibility, increasing ability to predict who may be at risk, recognition of the potential clinical impact of residual insulin secretion after diagnosis, and development of new immunomodulatory agents have supported an increasing number of clinical trials to prevent b-cell loss. Interventions can be targeted at 3 stages: before the development of autoimmunity (primary prevention), after autoimmunity is recognized (secondary prevention), or after diagnosis when significant numbers of b cells remain (tertiary prevention). Thus far, several agents show promise when given shortly after diagnosis, but no interventions before diagnosis have shown benefit. Knowledge in this area has grown quickly in recent years and will continue to grow rapidly with several international collaborative efforts underway.

Clinical and immunological features of celiac disease in patients with Type 1 diabetes mellitus

Celiac disease (CD) is one of the most frequent autoimmune disorders occurring in Type 1 diabetes mellitus (T1DM). The prevalence of CD in T1DM varies from 3 to 16%, with a mean prevalence of 8%. The clinical presentation of CD in T1DM is classified as symptomless in approximately half of cases, but a more accurate analysis often discloses a wide array of symptoms suggestive of CD. Both T1DM and CD show the same genetic background and an abnormal small intestinal immune response with inflammation and a variable grade of enteropathy. Serological screening for CD should be performed in all T1DM patients by means of antibodies to tissue transglutaminase at T1DM onset. T1DM patients found to be celiacs must be treated by a gluten-free diet. Potential CD cases (especially when asymptomatic) should be kept on a gluten-containing diet with a careful clinical and antibody follow-up, since many of them will not develop villous atrophy.

Autoimmune thyroid disease in Libyan children and young adults with type 1 diabetes mellitus

Diabetes mellitus is a common autoimmune endocrine disorder associated with organ-specific autoantibodies which are frequently detected at the time of diagnosis. Some of these antibodies are specific to the pancreas (GAD, IA2, ICA) while others are related to different autoimmune diseases.

AIM OF THE STUDY

To define the prevalence of thyroid autoimmune disease in Libyan patients with type 1 diabetes mellitus (T1DM) since no similar studies have been performed in Libya.

MATERIALS AND METHODS

Blood samples were collected from 218 patients with T1DM who are followed by the Pediatric Department, Tripoli Medical Center, Libya. All sera were analyzed in Italy (Laboratory of Immunopathology and Allergy, Udine). The patients were composed of 123 females (56.4%) and 95 males (43.6%), mean age 12.2 ± 4.6 years (range 2.1-24.5 years), mean duration of diabetes 4.7 ± 4.0 years (range 0.1-17.5 years). Sera were tested for anti-thyroperoxidase (TPO) and anti-thyroglobulin antibodies (TG). TSH and FT4 concentrations were measured in all subjects. GAD, IA-2 was also measured.

RESULTS

Of the diabetic children, 23.4% were positive for anti-microsomal peroxidase antibodies (TPO-Ab) and 7.8% for antithyroglobulin antibodies (TG-Ab); whereas 6.9% of the patients were positive for both TPO-Ab and TG-Ab. Of the T1DM patients who were positive for TPO-Ab, 66.6% were females. The majority (57%) of the patients who were positive for TPO had diabetes for longer than 5 years. Five patients (2.3%) had evidence of subclinical hypothyroidism whereas two patients (0.9%) had overt hypothyroidism. Two patients had subclinical hyperthyroidism and two (0.9%) had overt hyperthyroidism. Interestingly, 16.2% of patients were positive for both thyroid and pancreatic antibodies.

CONCLUSIONS

The prevalence of autoimmune thyroid disease in type 1 diabetic patients is higher than in the general population. A routine screening strategy should be implemented with the determination of anti-thyroid antibodies and TSH in type 1 diabetic patients, particularly in girls, and in patients with diabetes of more than 5 years duration. Patients who have positive TPO antibodies may need the assessment of thyroid function at shorter intervals.

The interface between thyroid and diabetes mellitus

Thyroid disease and type 1 but also type 2 diabetes mellitus (DM) are strongly associated, and this has important clinical implications for insulin sensitivity and treatment requirements. The pathophysiological basis of this association has only recently been better elucidated. It rests on a complex interaction of common signalling pathways and, in the case of type 1 diabetes and autoimmune thyroid disease, on a linked genetic susceptibility. The pathophysiological mechanisms underlying this linked regulation are increasingly being unravelled. They are exemplified in the regulation of 5' adenosine monophosphate-activated protein kinase (AMPK), a central target not only for the modulation of insulin sensitivity but also for the feedback of thyroid hormones on appetite and energy expenditure. The present review will discuss these concepts and their consequences for the clinical care of patients with DM and thyroid disorders. Moreover, it makes reference to the added effect of metformin in suppressing TSH.

Predictors of associated autoimmune diseases in families with type 1 diabetes: results from the Type 1 Diabetes Genetics Consortium

BACKGROUND

Type 1 diabetes (T1D) is a clinically heterogeneous disease. The presence of associated autoimmune diseases (AAIDs) may represent a distinct form of autoimmune diabetes, with involvement of specific mechanisms. The aim of this study was to find predictors of AAIDs in the Type 1 Diabetes Genetics Consortium data set.

METHODS

Three thousand two hundred and sixty-three families with at least two siblings with T1D were included. Clinical information was obtained using questionnaires, anti-GAD (glutamic acid decarboxylase) and anti-protein tyrosine phosphatase (IA-2) were measured and human leukocyte antigen (HLA) genotyping was performed. Siblings with T1D with and without AAIDs were compared and a multivariate regression analysis was performed to find predictors of AAIDs. T1D-associated HLA haplotypes were defined as the four most susceptible and protective, respectively.

RESULTS

One or more AAIDs were present in 14.4% of the T1D affected siblings. Age of diabetes onset, current age and time since diagnosis were higher, there was a female predominance and more family history of AAIDs in the group with AAIDs, as well as more frequent anti-GAD and less frequent anti-IA-2 antibodies. Risk and protective HLA haplotype distributions were similar, though DRB1*0301-DQA1*0501-DQB1*0201 was more frequent in the group with AAIDs. In the multivariate analysis, female gender, age of onset, family history of AAID, time since diagnosis and anti-GAD positivity were significantly associated with AAIDs.

CONCLUSIONS

In patients with T1D, the presence of AAIDs is associated with female predominance, more frequent family history of AAIDs, later onset of T1D and more anti-GAD antibodies, despite longer duration of the disease. The predominance of certain HLA haplotypes suggests that specific mechanisms of disease may be involved.

Additional autoimmune disease found in 33% of patients at type 1 diabetes onset

OBJECTIVE

We sought to define the prevalence of nonislet, organ-specific autoantibodies at diagnosis of type 1 diabetes and to determine the prevalence of comorbid autoimmune diseases.

RESEARCH DESIGN AND METHODS

Children (n = 491) diagnosed with type 1 diabetes at the Barbara Davis Center for Childhood Diabetes were screened for autoimmune thyroid disease (thyroid peroxidase autoantibodies [TPOAb]), celiac disease (tissue transglutaminase autoantibodies [TTGAb]), and Addison disease (21-hydroxylase autoantibodies [21OHAb]).

RESULTS

Of the 491 children, 161 had at least one nonislet autoantibody, and of these, 122 (24.8%) were positive for TPOAb, and 15 of the 122 (12.3%) had autoimmune thyroid disease. There were 57 (11.6%) who were positive for TTGAb, of whom 14 (24.6%) had celiac disease. Five (1.0%) were positive for 21OHAb, of whom one had Addison disease.

CONCLUSIONS

Many autoantibody-positive subjects present with additional autoimmune disorders. Detection of these autoantibodies at type 1 diabetes onset may prevent complications associated with delayed diagnosis of these disorders.

High titre of antiglutamic acid decarboxylase autoantibody is a strong predictor of the development of thyroid autoimmunity in patients with type 1 diabetes and latent autoimmune diabetes in adults

OBJECTIVE

Type 1 diabetes mellitus (T1DM) is frequently associated with autoimmune thyroid diseases (AITD), but little is known about the risk of AITD in latent autoimmune diabetes in adults (LADA). We evaluated the genetic and immunological factors involved in the development of thyroid autoimmunity in patients with LADA and T1DM.

PATIENTS AND MEASUREMENTS

One hundred and ninety T1DM and 135 LADA patients were recruited in the study. Thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb), glutamic acid decarboxylase antibody (GADA) and thyroid function were measured. The cytotoxic-lymphocyte-associated antigen-4 (CTLA-4) +49A/G and CT60 polymorphisms and the human leucocyte antigen (HLA)-DQA1-DQB1 genotype were determined.

RESULTS

The prevalence of thyroid antibodies (TGAb and/or TPOAb) and thyroid dysfunction was 27·4% and 9·5% in patients with T1DM, and 21·5% and 11·1% in patients with LADA. Thyroid-antibody-positive T1DM patients had higher frequencies of GADA and HLA-DQA1*03-DQB1*0401 haplotypes than thyroid-antibody negatives (P < 0·05). Thyroid-antibody-positive LADA patients had higher GADA titre, lower C-peptide levels and higher frequencies of HLA-DQA1*03-DQB1*0401 haplotypes (P < 0·05). The CTLA-4 +49A/G and CT60 polymorphism was associated with T1DM complicated with thyroid autoimmunity (OR = 2·33 and 2·54). Logistic regression revealed that only high-titre GADA was associated with development of thyroid autoimmunity in patients with T1DM and LADA (OR = 3·50 and 3·10, respectively), and the presence of thyroid antibody predicted high risk for thyroid dysfunction in patients with T1DM and LADA (OR = 9·25 and 10·70, respectively).

CONCLUSION

Regular screening of thyroid antibody and function are recommended, especially in patients with T1DM and LADA with high GADA titre.

Clinical implication of false-positive celiac serology in patients with ileal pouch

BACKGROUND

In patients with symptoms of pouchitis retractable to antibiotic therapy, serology is often ordered to exclude concurrent celiac disease. The clinical utility of celiac serology in patients with ileal pouches is unknown. The aim of this study was to investigate the clinical implications of false-positive celiac serology in patients with ileal pouches.

METHODS

All patients with pouches who had underlying ulcerative colitis and available celiac serology were included from the subspecialty Pouchitis Clinic at the Cleveland Clinic between 2002 and 2007. Chronic antibiotic-refractory pouchitis was diagnosed based on persistent symptomatic pouchitis after a 4-week single- or dual-antibiotic therapy.

RESULTS

A total of 126 patients were studied, and a false-positive celiac serology was observed in 19 patients. Chronic antibiotic-refractory pouchitis was diagnosed in 47% (9/19) of patients with false-positive celiac serology compared with 14% (15/107) of patients with a negative celiac serology (P = .003). In multivariate analysis, the association between false-positive celiac serology and chronic antibiotic-refractory pouchitis remained significant (odds ratio, 5.4; 95% confidence interval, 1.7-16.7; P = .004) after adjusting for sex (P = .03), pouch duration (P = .83), the presence of autoimmune disorders (P = .46), and extraintestinal manifestations (P = .63).

CONCLUSION

False-positive celiac serology appeared to be common in patients with ileal pouch-anal anastomosis and it may be associated with chronic antibiotic-refractory pouchitis.

Immunologic endocrine disorders

Autoimmunity affects multiple glands in the endocrine system. Animal models and human studies highlight the importance of alleles in HLA-like molecules determining tissue-specific targeting that, with the loss of tolerance, leads to organ-specific autoimmunity. Disorders such as type 1A diabetes, Graves disease, Hashimoto thyroiditis, Addison disease, and many others result from autoimmune-mediated tissue destruction. Each of these disorders can be divided into stages beginning with genetic susceptibility, environmental triggers, active autoimmunity, and finally metabolic derangements with overt symptoms of disease. With an increased understanding of the immunogenetics and immunopathogenesis of endocrine autoimmune disorders, immunotherapies are becoming prevalent, especially in patients with type 1A diabetes. Immunotherapies are being used more in multiple subspecialty fields to halt disease progression. Although therapies for autoimmune disorders stop the progress of an immune response, immunomodulatory therapies for cancer and chronic infections can also provoke an unwanted immune response. As a result, there are now iatrogenic autoimmune disorders arising from the treatment of chronic viral infections and malignancies.

Prevention of type 1 diabetes

Prevention of loss of beta cells in type 1 diabetes is a major goal of current research. Knowledge of the genetic susceptibility, increasing ability to predict who may be at risk, recognition of the potential clinical impact of residual insulin secretion after diagnosis, and development of new immunomodulatory agents have supported an increasing number of clinical trials to prevent beta-cell loss. Interventions can be targeted at 3 stages: before the development of autoimmunity (primary prevention), after autoimmunity is recognized (secondary prevention), or after diagnosis when significant numbers of beta cells remain (tertiary prevention). Thus far, several agents show promise when given shortly after diagnosis, but no interventions before diagnosis have shown benefit. Knowledge in this area has grown quickly in recent years and will continue to grow rapidly with several international collaborative efforts underway.

[Prevalence of anti-thyroid peroxidase and anti-adrenal 21-hidroxylase in type 1 diabetes patients]

There is still no consensus about the best strategy to screen Addison's disease (AD) in type 1 diabetes mellitus (T1DM) patients.

OBJECTIVE

The aim of this study was to determine the frequency of anti-21-hydroxilase (anti-21OH) in a multiethnic T1DM population and investigate if its presence is associated with any adrenal dysfunction or thyroid autoimmunity.

METHODS

Forty individuals underwent an interview and blood was drawn for anti-thyroperoxidase (anti-TPO), anti-21OH, TSH, free T4 and cortisol measurement.

RESULTS

Anti-21OH was found in 7.5% (n = 3), none with adrenal dysfunction. This antibody was not exclusively seen in patients with anti-TPO (+). Anti-TPO was positive in 25% and associated with higher TSH levels (p = 0.034) and older age (p = 0.009).

CONCLUSIONS

Although the frequency of anti-TPO in this sample was similar to previous studies, a higher prevalence of anti-21-OH was found. However, no coexisting adrenal dysfunction was detected, which does not support universal screening for AD in this group.

Heritability of levels of autoantibodies to thyroid antigens using the method of plotting regression of offspring on midparent (ROMP)

Only a few methods can be applied in a simple manner to estimate the genetic control of autoimmunity in humans. Here we examined the heritability of autoantibodies to two thyroid antigens; thyroglobulin (Tg) and thyroperoxidase (TPO, formerly known as thyroid microsomal antigen), using methods of regression of offspring on mid-parental values (ROMP). With the data sets available, affected and unaffected siblings were compared by this rapid screening method using results determined by hemagglutination (HA). The presence of both types of autoantibodies showed positive heritability in patients with Graves' thyrotoxicosis (TT), but it was not observed in chronic lymphocytic or Hashimoto's thyroiditis (CLT) patients. Since these assays have been extensively used over the years by most diagnostic and research laboratories, they should provide some insight as to which quantifiable parameters may be usefully accumulated to help select groups of patients and their families for further genetic study. ROMP may also be useful to determine the sequential appearance of different types of antibody in predicting disease onset in other family members, and in distinguishing maternal and paternal effects on imprinting. The method may be extended to study epitope spreading and other measures of disease progression.

Celiac disease associated antibodies in persons with latent autoimmune diabetes of adult and type 2 diabetes

BACKGROUND

Celiac Disease (CD) is present in 1-16.4% of patients with type 1 diabetes mellitus. The most important serological markers of CD are anti-endomysial (EMA), anti-tissue transglutaminase (tTGA) and antigliadin antibodies (AGA).

AIM/HYPOTHESIS

The objective of this work is to determine the frequency of tTGA and/or AGA in latent autoimmune diabetes of adult (LADA) and subjects with type 2 diabetes (T2DM), as well as to evaluate their relation with several clinical and biochemical characteristics.

SUBJECTS AND METHODS

Forty three subjects with LADA and 99 with T2DM were studied. The presence of AGA, tTGA was determined in the sera of these patients. The variables: sex, age, duration of diabetes, treatment, body mass index (BMI) and fasting blood glucose concentration were also recorded.

RESULTS

No differences were found in the frequency of celiac disease associated antibodies between LADA and T2DM subjects. The presence of celiac disease related antibodies was more frequent in patients with a normal or low BMI.

CONCLUSIONS

Celiac disease does not seem to be related with pancreatic autoimmunity in type 2 diabetes. Celiac disease causes a decrease of body mass index in type 2 diabetes while pancreatic islet autoimmunity in this entity masks this effect.

Regulatory T cells in diabetes and gastritis

Patients with Type 1 diabetes mellitus (T1D) have an increased prevalence of associated organ-specific autoimmune diseases such as pernicious anemia whose histological substrate is a chronic atrophic gastritis (CAG). Latent pernicious anemia precedes clinically-manifest pernicious anemia and may be difficult to detect solely on simple analytical grounds. We recently described an increased prevalence of clinically-latent pernicious anemia in T1D using low concentrations of pepsinogen I, a zymogen of pepsin present in gastric mucosa, as a useful additional diagnostic marker, besides parietal cell antibodies, for screening latent pernicious anemia in T1D. The failure of peripheral tolerance mechanisms such as regulatory T cells (Treg) might be involved in CAG development in T1D patients. Indeed, functional defects in Tregs have been described in T1D patients. To this end, the percentage of Tregs in peripheral blood of T1D-CAG patients was analyzed and compared with those of a group of T1D without associated autoantibodies and a healthy control group. Tregs levels were also analyzed in gastric biopsies of T1D-CAG patients. The results obtained have led to new questions regarding the pathogenic mechanisms implicated in the development of associated autoimmune diseases in T1D.

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.

Factors for thyroid autoimmunity in children and adolescents with type 1 diabetes mellitus

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is associated with an autoimmune reaction to thyroid antigens including thyroid peroxidase (anti-TPO) and thyroglobulin (anti-Tg).

AIMS

We determined in children with T1DM the relationship of positive anti-thyroid antibodies to potential risk factors, including, age, gender, duration of diabetes, and glutamic acid decarboxylase antibodies (anti-GAD).

MATERIALS AND METHODS

We studied 144 children and adolescents with T1DM. Their age was 12.3 +/- 4.6 (mean +/- SD) years, and duration of diabetes was 4.6 +/- 3.8 years. Anti-thyroid antibodies were determined using a luminescence method and anti-GAD using an enzyme-linked immunosorbent assay.

RESULTS

The prevalence rates of anti-thyroid antibodies among the children with T1DM in our study were: anti-TPO (17.4%), anti-Tg (11.1%), and of both anti-thyroid antibodies (10.4%). The presence of serum anti-thyroid antibodies was positively associated with age (16.6 years in those with positive tests versus 12.0 years in those with negative tests, P = 0.027), duration of diabetes (7.4 versus 4.3 years, P = 0.031), and serum TSH (Thyroid-stimulating hormone) levels (4.8 versus 2.3 microIU/mL, P = 0.002). The presence of both anti-thyroid antibodies was associated with female sex (boys: 4/75 (5.3%), girls: 11/69 (15.9%), chi-square = 6.44, P = 0.04). Subclinical autoimmune thyroiditis (SAIT) was present in 55.5% of the patients with thyroid antibody-positivity and was positively associated with age (16.6 versus 12.0 years, P = 0.001) and diabetes duration (7.6 versus 4.2 years, P = 0.001). Multiple logistic regression analysis revealed that the development of anti-thyroid antibodies was predicted by: 1) the presence of anti-GAD (odds ratio (OR) 1.45, 95% confidence interval (CI) 1.09-1.92), 2) the presence of a second anti-thyroid antibody (OR 134.4, 95% CI 7.7-2350.3), and 3) older age (OR 22.9, 95% CI 1.13-463.2).

CONCLUSIONS

Thyroid autoimmunity was associated with female gender, increasing age, long diabetes duration, the persistence of anti-GAD, and with TSH elevation, indicating subclinical hypothyroidism.

Celiac disease and the endocrinologist: a diagnostic opportunity

OBJECTIVE

To review the association of celiac disease and various endocrine disorders and present the related clinical experience of a 3-physician adult endocrinology practice.

METHODS

We provide an overview of the pertinent literature, discuss the clinical manifestations, genetics, and pathogenesis of celiac disease, and describe our clinical experience during a 5-year period.

RESULTS

Celiac disease has been associated with numerous disorders, including several conditions treated by endocrinologists-type 1 diabetes mellitus, autoimmune thyroid disease, Addison disease, osteomalacia, secondary hyperparathyroidism, vitamin D or iron deficiency, fertility problems, hypogonadism in men, and autoimmune hypopituitarism. After our clinical awareness was raised about these potential comorbidities, 18 patients were newly diagnosed with celiac disease in our clinical practice during a 5-year interval. All patients had been referred for endocrine evaluation or were undergoing follow-up for ongoing management of endocrine disorders. When a "celiac-associated" endocrine disorder coexists with other factors associated with celiac disease, we recommend performance of IgA class antibody testing, and either antiendomysial or anti-tissue transglutaminase antibodies provide high specificity and sensitivity for the diagnosis of celiac disease.

CONCLUSION

Endocrinologists have an opportunity to diagnose celiac disease, a relatively common disorder with profound clinical implications that can often be associated with various endocrinopathies.