Thyroid-related autoantibodies and celiac disease: a role for a gluten-free diet?

Seroprevalence of Celiac Disease in Mexican Mestizo Patients With Autoimmune Thyroid Disease

GOALS

This study aimed to assess the seroprevalence of celiac disease in Mexican patients with autoimmune thyroid diseases, hypothesizing that prevalence would align with rates observed in other populations.

BACKGROUND

The association between celiac disease and autoimmune thyroid diseases has been documented globally, with varying seroprevalence rates. Historically, Mexican Mestizos were considered at low risk for celiac disease, yet recent findings suggest similar prevalence to other regions. However, data regarding Hispanic patients with autoimmune thyroid diseases are limited.

STUDY

This observational, descriptive, cross-sectional study involved 170 Mexican Mestizo patients diagnosed with autoimmune thyroid diseases, specifically Hashimoto thyroiditis or Graves' disease. Data on demographics, disease history, and symptoms were collected. Celiac disease seroprevalence was assessed using immunoglobulin A anti-tissue transglutaminase, immunoglobulin A deamidated gliadin peptide, and immunoglobulin G deamidated gliadin peptide antibodies, with values above a specified threshold considered positive.

RESULTS

Among the participants, 92.4% were female, with a mean age of 45.4 years. Hashimoto thyroiditis was present in 80.6% of cases, whereas Graves disease accounted for 19.4%. The overall celiac disease seroprevalence was 8.8% (95% CI; 5.4-14.1). All individuals with positive serology had Hashimoto thyroiditis, and although no gastrointestinal symptoms were linked to seropositivity, anemia was more common in celiac-positive subjects.

CONCLUSIONS

Celiac disease seroprevalence among Mexican Mestizo patients with autoimmune thyroid diseases aligns with other populations. Serological screening for celiac disease is recommended, even in the absence of gastrointestinal symptoms. Further biopsy-confirmed studies are necessary.

Thyroid, Diet, and Alternative Approaches

BACKGROUND

Increasingly, patients are asking their physicians about the benefits of dietary and alternative approaches to manage their diseases, including thyroid disease. We seek to review the evidence behind several of the vitamins, minerals, complementary medicines, and elimination diets that patients are most commonly using for the treatment of thyroid disorders.

SUMMARY

Several trace elements are essential to normal thyroid function, and their supplementation has been studied in various capacities. Iodine supplementation has been implemented on national scales through universal salt iodization with great success in preventing severe thyroid disease, but can conversely cause thyroid disorders when given in excess. Selenium and zinc supplementation has been found to be beneficial in specific populations with otherwise limited generalizability. Other minerals, such as vitamin B12, low-dose naltrexone, and ashwagandha root extract, have little to no evidence of any impact on thyroid disorders. Avoidance of gluten and dairy has positive impacts only in patients with concomitant sensitivities to those substances, likely by improving absorption of levothyroxine. Avoidance of cruciferous vegetables and soy has little proven benefit in patients with thyroid disorders.

CONCLUSION

While many patients are seeking to avoid conventional therapy and instead turn to alternative and dietary approaches to thyroid disease management, many of the most popular approaches have no proven benefit or have not been well studied. It is our responsibility to educate our patients about the evidence for or against benefit, potential harms, or dearth of knowledge behind these strategies.

Gluten-free diet attenuates the impact of exogenous vitamin D on thyroid autoimmunity in young women with autoimmune thyroiditis: a pilot study

Although both exogenous vitamin D and a gluten-free diet were found to reduce thyroid antibody titers, no study investigated interactions between gluten intake and vitamin D status in patients with autoimmune thyroid disorders. The aim of the present study was to assess whether the gluten-free diet determines the effect of vitamin D treatment on thyroid autoimmunity and thyroid function in young women with autoimmune (Hashimoto's) thyroiditis. The study compared two groups of euthyroid premenopausal women with this disorder, matched for thyroid antibody titers: 31 women with non-celiac gluten sensitivity complying for at least 12 months with the gluten-free diet and 31 unaffected sisters of women with non-celiac gluten sensitivity remaining without any dietary intervention. Plasma titers of thyroid peroxidase and thyroglobulin antibodies, as well as plasma concentrations of thyrotropin, free thyroid hormones, prolactin, 25-hydroxyvitamin D and high-sensitive C-reactive protein were measured at entry and after a six-month follow-up. Moreover, at both time points, the structure parameters of thyroid homeostasis were assessed. Although exogenous vitamin D decreased titers of thyroid peroxidase and thyroglobulin antibodies and increased 25-hydroxyvitamin D levels in each treatment group, this effect was less pronounced in patients on the gluten-free diet than in patients not following any dietary recommendations. Only in the latter group of patients, vitamin D increased SPINA-GT. Treatment-induced changes in thyroid peroxidase and thyroglobulin antibodies correlated with the impact of treatment on 25-hydroxyvitamin D levels. The obtained results suggest that gluten-free diet may impair beneficial effects of exogenous vitamin D in individuals with Hashimoto's thyroiditis.

Celiac Disease and Autoimmune Thyroid Disease: The Two Peas in a Pod

Celiac disease (CD) is a small intestinal inflammatory disease commonly seen in the Western population. It has been observed that patients with monoglandular and polyglandular autoimmunity have a higher prevalence of celiac disease. Hashimoto's thyroiditis (HT) and Graves' disease (GD), which mainly constitute the autoimmune thyroid diseases (AITD), characterized by lymphocytic infiltration of the thyroid parenchyma, are noted to be frequently associated with celiac disease. The fundamental mechanism of this frequent coexistence is thought to be a shared genetic background. Due to the subclinical nature of the celiac disease, the diagnosis is often missed or made coincidentally during screening. The rising prevalence of the celiac disease among AITD patients has urged researchers to investigate the link between the two. We reviewed the most recent and relevant literature on the intriguing relationship between celiac disease and thyroid autoimmunity. The objectives of this article were to study the shared genetic background, the incidence of CD in AITD, the effect of a gluten-free diet on AITD, and the need for routine screening of CD in AITD patients.

What about TSH and Anti-Thyroid Antibodies in Patients with Autoimmune Thyroiditis and Celiac Disease Using a Gluten-Free Diet? A Systematic Review

The prevalence of celiac disease (CD) in patients with chronic autoimmune thyroiditis (CAIT) is estimated to be between 2 and 7.8%. A gluten-free diet (GFD) in patients with CD is suggested to have a beneficial effect on CAIT. Thus, the present systematic review was undertaken to achieve more robust evidence about the change in thyroid stimulating hormone (TSH) and thyroid-specific antibodies (T-Ab) levels obtained in CD patients following a GFD. A specific search strategy was planned. The last search was performed on March 2022. The following data were mainly searched for in order to be extracted: sample size, mean and/or median with standard deviation (SD), and error (SE), individually, of thyroid hormones and T-Ab at baseline and after GFD, and the duration of the study. The initial search retrieved 297 records and 6 articles met the inclusion criteria. In total, 50 patients with both CD and CAIT and 45 controls were reported. The effects of a GFD on the thyroid hormonal and immunological profile could be extracted only in a part of the studies. Two studies were case reports. A low risk of bias was observed. These findings advise further studies, ideally randomized, in order to better investigate the potential relationship between GFD and thyroid homeostasis. The level of evidence is not still sufficient to recommend GFD to patients with CAIT.

Complex Inheritance of Rare Missense Variants in PAK2, TAP2, and PLCL1 Genes in a Consanguineous Arab Family With Multiple Autoimmune Diseases Including Celiac Disease

BACKGROUND

Autoimmune diseases (AIDs) share a common molecular etiology and often present overlapping clinical presentations. Thus, this study aims to explore the complex molecular basis of AID by whole exome sequencing and computational biology analysis.

METHODS

Molecular screening of the consanguineous AID family and the computational biology characterization of the potential variants were performed. The potential variants were searched against the exome data of 100 healthy individuals and 30 celiac disease patients.

RESULT

A complex inheritance pattern of PAK2 (V43A), TAP2 (F468Y), and PLCL1 (V473I) genetic variants was observed in the three probands of the AID family. The PAK2 variant (V43A) is a novel one, but TAP2 (F468Y) and PLCL1 (V473I) variants are extremely rare in local Arab (SGHP and GME) and global (gnomAD) databases. All these variants were localized in functional domains, except for the PAK2 variant (V43A) and were predicted to alter the structural (secondary structure elements, folding, active site confirmation, stability, and solvent accessibility) and functional (gene expression) features. Therefore, it is reasonable to postulate that the dysregulation of PAK2, TAP2, and PLCL1 genes is likely to elicit autoimmune reactions by altering antigen processing and presentation, T cell receptor signaling, and immunodeficiency pathways.

CONCLUSION

Our findings highlight the importance of exploring the alternate inheritance patterns in families presenting complex autoimmune diseases, where classical genetic models often fail to explain their molecular basis. These findings may have potential implications for developing personalized therapies for complex disease patients.

Gluten-free diet can ameliorate the symptoms of non-celiac autoimmune diseases

CONTEXT

A gluten-free diet (GFD) is the recommended treatment for gluten-dependent disease. In addition, gluten withdrawal is popular and occasionally is suggested as a treatment for other autoimmune diseases (ADs).

OBJECTIVE

The current systematic review summarizes those entities and discusses the logic behind using a GFD in classical non-gluten-dependentADs.

DATA SOURCES

A search for medical articles in PubMed/MEDLINE, Web of Sciences, LILACS, and Scielo published between 1960 and 2020 was conducted, using the key words for various ADs and GFDs.

DATA EXXTRACTION

Eight-three articles were included in the systematic review (using PRISMA guidelines).

DATA ANALYSIS

Reduction in symptoms of ADs after observance of a GFD was observed in 911 out of 1408 patients (64.7%) and in 66 out of the 83 selected studies (79.5%). The age of the patients ranged from 9 months to 69 years. The duration of the GFD varied from 1 month to 9 years. A GFD can suppress several harmful intraluminal intestinal events. Potential mechanisms and pathways for the action of GFD in the gut - remote organs' axis have been suggested.

CONCLUSION

A GFD might represent a novel nutritional therapeutic strategy for classical non-gluten-dependent autoimmune conditions.

Whether a Gluten-Free Diet Should Be Recommended in Chronic Autoimmune Thyroiditis or Not?-A 12-Month Follow-Up

Elimination diets have recently become extremely popular among people with autoimmune diseases. A gluten-free diet is indicated in celiac disease (CD), but some studies show its effectiveness in cases of autoimmunity. The aim of this study was to assess whether the use of a gluten-free diet is also effective in patients with chronic autoimmune thyroid disease (cAITD), which is the most common thyroid autoimmune pathology associated with chronic inflammation, over-reactivity of the immune system, auto-destruction of thyrocytes and hypothyroidism. The final analysis of the study included 62 Caucasian women randomized into a control group (CG: n = 31) and an experimental group on a gluten-free diet (GFDG: n = 31), were subject to a 12-month follow-up, during which the concentrations of thyrotropin (TSH), free triiodothyronine (fT3), free thyroxine (fT4), anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-TG) antibodies were assessed at baseline and after 3, 6 and 12 months. During the 12-month follow-up between the CG and the GFDG, no differences were found in anti-TPO and anti-TG antibodies, fT3 or fT4 levels, except a significant reduction in TSH levels in the GFDG. Additionally, performed analysis between individual appointments presented no significant differences in changes in the median concentrations of anti-TPO, anti-TG or fT3, but confirmed a significant decrease in TSH and showed accessory an increase in fT4 after 12 months in GFDG. Statistical analyses performed separately for both groups indicated a constant reduction of anti-TG concentrations in the GFDG. In conclusion, a GFD may be administered in cAITD after ruling out celiac disease, but it is necessary to perform more studies to assess if cAITD patients achieve the benefits of following a GFD. Patients with cAITD should be offered proper nutrition education combined with a healthy lifestyle promotion.

Prevalence of latent and overt polyautoimmunity in autoimmune thyroid disease: A systematic review and meta-analysis

BACKGROUND

Thyroid autoimmunity is the most frequent condition involved in polyautoimmunity (PolyA). However, the frequency of latent and overt PolyA in patients with autoimmune thyroid disease (AITD) as the index condition is unknown. Therefore, the purpose of this study was to determine the prevalence of these types of PolyA in patients with AITD as the index condition.

METHODS

This study adhered to the relevant sections of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. Searches through MEDLINE, Embase and LILACS were done to find articles in Spanish and English. Relevant vocabulary terms and key terms related to AITD and other autoimmune diseases were used. Two investigators independently screened the eligible studies, extracted data and assessed the quality and risk of bias. Fixed and random effect models were used accordingly. Cluster analysis was used to determine similarities among diseases in the articles included (based on Jaccard index).

RESULTS

A total of 56 articles fulfilled the inclusion criteria. Of these, 25 were case-controls, 17 were cohorts, and 14 were cross-sectional studies. These studies included a total of 47 509 patients. Female was the predominant gender and included 38 950 patients (81.23%, 95% CI: 80.85-81.60). Graves' disease (GD) was the most common type of thyroid autoimmunity (69.16%, 95% CI: 68.23-70.07). Globally, overt PolyA was found in 13.46% of the patients with AITD. This type of PolyA was represented mainly by type 1 diabetes and autoimmune gastritis. Latent PolyA was presented in 17.45% of the patients, and anti-proinsulin, anti-parietal cells and dsDNA antibodies were the most common. HT had the highest frequency of overt PolyA in Europe (15.60%, 95% CI: 14.72-16.53), whereas latent PolyA was most common in patients with GD in Asia (21.03%, 95% CI: 17.76-24.71). Overt and latent PolyA were associated with gastrointestinal and endocrinological ADs in most of cases and clustered with rheumatological, dermatological and neurological ADs.

CONCLUSIONS

Latent and overt PolyA are common in patients with AITD. These results provide insightful information for early diagnosis and management of concurrent ADs in patients with AITD. Aggregation of ADs in different clusters may help to define different phenotypes associated with thyroid autoimmunity that are critically relevant in clinical settings.

Current Evidence on the Efficacy of Gluten-Free Diets in Multiple Sclerosis, Psoriasis, Type 1 Diabetes and Autoimmune Thyroid Diseases

In this review, we summarize the clinical data addressing a potential role for gluten in multiple sclerosis (MS), psoriasis, type 1 diabetes (T1D) and autoimmune thyroid diseases (ATDs). Furthermore, data on the prevalence of celiac disease (CD) and gluten-related antibodies in the above patient groups are presented. Adequately powered and properly controlled intervention trials investigating the effects of a gluten-free diet (GFD) in non-celiac patients with MS, psoriasis, T1D or ATDs are lacking. Only one clinical trial has studied the effects of a GFD among patients with MS. The trial found significant results, but it is subject to major methodological limitations. A few publications have found beneficial effects of a GFD in a subgroup of patients with psoriasis that were seropositive for anti-gliadin or deamidated gliadin antibodies, but no effects were seen among seronegative patients. Studies on the role of gluten in T1D are contradictive, however, it seems likely that a GFD may contribute to normalizing metabolic control without affecting levels of islet autoantibodies. Lastly, the effects of a GFD in non-celiac patients with ATDs have not been studied yet, but some publications report that thyroid-related antibodies respond to a GFD in patients with concomitant CD and ATDs. Overall, there is currently not enough evidence to recommend a GFD to non-celiac patients with MS, psoriasis, ATDs or T1D.

Toward New Paradigms in the Follow Up of Adult Patients With Celiac Disease on a Gluten-Free Diet

Gluten free diet is the only available treatment for celiac disease (CeD). Patients with CeD who do not adhere to a strict gluten-free diet (GFD) have been found to have complications involving nutritional deficiencies, increased risk of bone fractures, increased risk of mortality, and certain types of cancers. Complete removal of gluten from the diet in a patient with CeD often results in symptomatic, serologic, and histologic remission. However, strict compliance with the diet is challenging. Long-term follow-up care is needed to assure treatment compliance and positive health outcomes. Monitoring celiac specific serology, nutrient deficiencies, bone mineral density, and assessment of GFD compliance have been recommended in clinical practice. However, there is no consensus on which specific tests and how often they should be performed during the follow up. Here, we have performed a review of the literature on current strategies to follow up patients with CeD. There are new tools for monitoring adherence to the GFD which could change some paradigms in following up treated patients.

Prevalence of celiac disease in patients with Down syndrome: a meta-analysis

Background

The association between Down syndrome and celiac disease has been reported by many studies. However, the prevalence of celiac disease (CD) in Down syndrome (DS) varies considerably across studies (from 0 % to 19 %). The aim of this study was to use meta-analysis to exam the prevalence of CD in patients with DS.

Methods

A systematic search of English articles from Pubmed, Web of Science and CNKI without year limitation. Data were extracted by two independent observers and pooled using a random effects model by the Comprehensive Meta-Analysis Version 2 software.

Results

A pooled analysis, based on 31 studies included 4383 individuals, revealed prevalence of biopsy-confirmed CD of 5.8 % (95 % CI = 4.7-7.2 %) in patients with DS. Sub-group analysis showed a slightly higher prevalence of CD in children with DS (6.6 %; 17 studies), than in age mixed samples with both children and adults (5.1 %; 13 studies). In addition, most of the studies included in this meta-analysis were from Europe and America, with the prevalence of celiac disease of 6 % (21 studies) and 5.7 % (6 studies) in DS patients, respectively. Furthermore, meta-regression analysis suggested that proportion of antibody-positive individuals that underwent small intestine biopsy had moderating effect on the outcome of the meta-analysis.

Conclusions

These results demonstrated that patients (children) with Down syndrome had high prevalence of CD (more than one in twenty). The prevalence is high enough to motivate screening CD in DS children.

Increased Incidence of Thyroid Disease in Patients with Celiac Disease: A Systematic Review and Meta-Analysis

The prevalence of thyroid disease is likely increased among individuals with celiac disease (CD). In addition, exposure to gluten-free treatment may be associated with a risk of thyroid disease, but this association remains controversial. A systematic review was performed to evaluate the association between thyroid disease and CD. The articles were obtained from the PubMed, Web of Science, Embase, and Chinese WanFang bibliographical databases for the period up to May 2016. The results were analysed in a meta-analysis with odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs). There were 13 articles in this meta-analysis, including 15629 CD cases and 79342 controls. Overall, the prevalence of thyroid disease in patients with CD was significantly increased compared with that in the control groups (OR 3.08, 95% CI 2.67-3.56, P<0.001). Moreover, there was no significant difference in the OR between the gluten-treated and untreated groups (OR 1.08, 95% CI 0.61-1.92, P = 0.786). The results of our meta-analysis support the hypothesis that the prevalence of thyroid disease in patients with CD is increased compared with that in controls, which suggests that CD patients should be screened for thyroid disease. The effect of gluten-free treatment on thyroid disease needs further investigation.

Prevalence of Celiac Disease in Patients with Autoimmune Thyroid Disease: A Meta-Analysis

BACKGROUND

Several screening studies have indicated an increased prevalence of celiac disease (CD) among individuals with autoimmune thyroid disease (ATD), but estimates have varied substantially.

OBJECTIVE

The aim of this study was to examine the prevalence of CD in patients with ATD.

METHOD

A systematic review was conducted of articles published in PubMed Medline or EMBASE until September 2015. Non-English papers with English-language abstracts were also included, as were research abstracts without full text available when relevant data were included in the abstract. Search terms included "celiac disease" combined with "hypothyroidism" or "hyperthyroidism" or "thyroid disease." Fixed-effects inverse variance-weighted models were used. Meta-regression was used to examine heterogeneity in subgroups.

RESULTS

A pooled analysis, based on 6024 ATD patients, found a prevalence of biopsy-confirmed CD of 1.6% [confidence interval (CI) 1.3-1.9%]. Heterogeneity was large (I(2) = 70.7%). The prevalence was higher in children with ATD (6.2% [CI 4.0-8.4%]) than it was in adults (2.7%) or in studies examining both adults and children (1.0%). CD was also more prevalent in hyperthyroidism (2.6% [CI 0.7-4.4%]) than it was in hypothyroidism (1.4% [CI 1.0-1.9%]).

CONCLUSIONS

About 1/62 patients with ATD have biopsy-verified CD. It is argued that patients with ATD should be screened for CD, given this increased prevalence.

Assessment of coeliac disease prevalence in patients with Down syndrome in Poland - a multi-centre study

Introduction

The results of studies assessing whether patients with Down syndrome have increased risk of coeliac disease are contradictory. The prevalence of coeliac disease in patients with Down syndrome is estimated at a wide range between 1% to as much as 18.6%.

Aim

To assess coeliac disease prevalence in patients with Down syndrome in Poland.

Material and methods

The study enrolled 301 patients with Down syndrome from six centres in Poland (Wroclaw, Sandomierz, Rzeszow, Grudziadz, Katowice, and Bydgoszcz). We measured the concentration of anti-tissue transglutaminase IgA antibodies and anti-deamidated gliadin peptide IgG antibodies in all patients. Patients with abnormal positive (> 10 U/ml) or inconclusive (7–10 U/ml) result of the serological test were offered endoscopic biopsy of the small intestine in the main centre.

Results

In 31 (10.3%) patients increased concentrations of the investigated antibodies were found, including 19 (6.3%) patients with increased tTg-IgA concentration, 27 (8.97%) patients with increased concentration of DGP-IgG, and 15 (4.98%) patients with increased concentration of both types of antibodies. Endoscopic biopsy of the small intestine was planned for all 31 patients with abnormal results of at least one antibody test and for 2 patients with inconclusive results. One of them suffered from previously diagnosed and histologically confirmed coeliac disease. Biopsy was not conducted in 9 patients due to contraindications, lack of their consent, or introduction of a gluten-free diet by the parents before the examination. In a group of 23 patients who underwent endoscopic biopsy of the small intestine, in 15 patients the histopathological picture of the small intestinal mucosa was typical for coeliac disease, 2 patients were diagnosed with lesions of grade 1 according to the classification by Marsh-Oberhuber, 1 patient was diagnosed with focal shortening of villi and hypertrophy of the crypts with no intraepithelial lymphocytosis (remains under gastrological observation), 2 patients were diagnosed with mucosal inflammation of the duodenum, and 3 patients were found to have a normal histopathological picture of the small intestine. Analysis of the data included in the questionnaires of all patients showed no statistically significant differences in the body height, body mass index, prevalence of abdominal pain, diarrhoea, constipations, recurrent stomatitis, enamel hypoplasia, thyroid diseases, or hypertransaminasaemia between the groups of patients with normal and abnormal serological test results. Significantly higher prevalence of abdominal flatulence (p < 0.05) and epilepsy (p < 0.05) was found in the group of patients whose serological test results were negative.

Conclusions

Patients with Down syndrome are a high-risk group for coeliac disease in the Polish population, with an estimated prevalence of at least 5.4%. Serological tools based on tTG-IgA and DGP-IgG tests are useful for the diagnosis of coeliac disease in Down syndrome patients. tTG-IgA test may be superior to DGP-IgG test in patients with normal total IgA level. Tests for coeliac disease should be carried out in all Polish patients with Down syndrome, regardless of the clinical picture.

Celiac disease detection in hypothyroid patients requiring elevated thyroid supplementation: A prospective cohort study

BACKGROUND

Celiac disease (CD) is associated with hypothyroidism, but the disease prevalence is not thought to be great enough to warrant testing all hypothyroid patients. We hypothesized that hypothyroid patients with concomitant CD would require elevated doses of levothyroxine, and there is a threshold daily dose, above which, hypothyroid patients should be tested for CD.

METHODS

Hypothyroid patients presenting to the endoscopy or endocrinology clinics at the University of Vermont Medical Center were included. Patients were categorized by whether or not they required ≥125mcg/day of levothyroxine. A serum tissue transglutaminase (tTG) was performed on enrolled patients. Patients with an elevated serum tTG underwent endoscopy with duodenal biopsies. Symptoms were assessed by the Gastrointestinal Symptom Rating Scale.

RESULTS

Overall, 500 patients were enrolled and 29% (144 patients) required ≥125mcg/day of levothyroxine. CD was detected in 9 patients. The prevalence of CD ranged from 1.8% in our entire cohort to 12.5% in patients requiring ≥200mcg/day of levothyroxine. Eight patients with CD (89%) required ≥125mcg/day of levothyroxine. Patients who required ≥125mcg/day of levothyroxine had a significantly increased risk of CD (p<0.001). CD was detected in 5.6% of patients requiring ≥125mcg/day of levothyroxine.

CONCLUSIONS

Hypothyroid patients requiring elevated daily doses of levothyroxine are more likely to have CD. Hypothyroid patients requiring ≥125mcg/day of levothyroxine should undergo serologic testing for CD.

Thyroid-associated orbitopathy is linked to gastrointestinal autoimmunity

Common autoimmune disorders tend to co-exist in the same subjects and cluster in families. The objective of this study was to determine the prevalence of autoimmune co-morbidity in patients with autoimmune thyroid disease (AITD) with and without thyroid-associated orbitopathy (TAO). This was a cross-sectional study conducted at an academic tertiary referral centre. Of 1310 patients with AITD [n = 777 or 59% with Graves' disease (GD) and n = 533, 41% with Hashimoto's thyroiditis (HT)] followed at a specialized joint thyroid-eye out-patient clinic, 176 (13·4%) had an adult type of the autoimmune polyglandular syndrome, 129 (9·8%) type 1 diabetes, 111 (8·5%) coeliac disease, 60 (4·6%) type A autoimmune gastritis, 57 (4·4%) vitiligo and 25 (1·9%) Addison's disease. Coeliac disease and autoimmune gastritis were associated positively with GD [odds ratio (OR) = 2·18; P = 0·002 and OR = 6·52; P < 0·001], whereas type 1 diabetes, Addison's disease, autoimmune primary hypogonadism, alopecia areata, rheumatoid arthritis and Sjögren's syndrome were 'protective' for GD and thus linked to HT, OR = 0·49 (P < 0·001), 0·06 (P < 0·001), 0·25 (P < 0·001), 0·50 (P = 0·090) and 0·32 (P = 0·003), respectively. Of 610 (46·6%) AITD patients with TAO, 584 (95·7%) and 26 (4·3%) had GD and HT, respectively (P < 0·001). TAO was most prevalent in GD patients with coeliac disease (94%, OR = 1·87, P < 0·001). Multivariate analysis showed high OR for coeliac disease and autoimmune gastritis (3·4 and 4·03, both P < 0·001) pertaining to the association with TAO while type 1 diabetes, Addison's disease and alopecia areata were protective for TAO. In patients with TAO, coeliac disease is the most prevalent co-morbid autoimmune condition and rates are increased compared to GD patients without TAO.

Prevalence and clinical features of celiac disease in patients with autoimmune thyroiditis: cross-sectional study

CONTEXT AND OBJECTIVE

Celiac disease is an autoimmune disorder with an average prevalence of 1% in Europe and the United States. Because of strong European ancestry in southern Brazil, this study aimed to evaluate the seroprevalence of celiac disease among autoimmune thyroiditis patients.

DESIGN AND SETTING

Cross-sectional study in a public university hospital.

METHODS

This cross-sectional prevalence study included autoimmune thyroiditis patients who were tested for anti-endomysial and anti-transglutaminase antibodies between August 2010 and July 2011.

RESULTS

Fifty-three patients with autoimmune thyroiditis were included; 92.5% were women, with mean age of 49.0 ± 13.5 years. Five patients (9.3%) were serologically positive for celiac disease: three of them (5.6%) were reactive for anti-endomysial antibodies and two (3.7%) for anti-transglutaminase. None of them exhibited anemia and one presented diarrhea. Endoscopy was performed on two patients: one with normal histology and the other with lymphocytic infiltrate and villous atrophy.

CONCLUSION

The prevalence of celiac disease among patients with autoimmune thyroid disease was 9.3%; one patient complained of diarrhea and none presented anemia. Among at-risk populations, like autoimmune thyroiditis patients, the presence of diarrhea or anemia should not be used as a criterion for indicating celiac disease investigation. This must be done for all autoimmune thyroiditis patients because of its high prevalence.

Clinical utility of celiac disease-associated HLA testing

BACKGROUND

Negative predictive value (NPV) of celiac disease (CD)-related human leukocyte antigens (HLA) DQ2 and DQ8 approaches 100 % in individual patients. However, studies evaluating its exclusionary utility in patient groups are lacking.

AIM

We aim to assess the performance of HLA testing when applied to patient groups with varying characteristics and propose evidence-based recommendations for its clinical use.

METHODS

Demographic and clinical information was recorded in patients undergoing HLA testing. Using predetermined criteria, patients were classified as CD, non-CD, or indeterminate. Diagnostic yield of HLA testing was defined as the percentage of patients in whom CD could be excluded based on negative HLA test.

RESULTS

Two hundred and fifty-six patients underwent testing for CD-related HLA DQ2 and DQ8. 102 (100 non-CD, 2 CD) patients tested HLA negative for a 98 % NPV and 39 % diagnostic yield. Diagnostic yield was highest (60 %) in patients with intraepithelial lymphocytosis plus normal IgA tissue transglutaminase antibody (IgA-tTG) and lowest in patients with positive IgA-tTG plus villous atrophy (0 %). CD was diagnosed in two HLA-negative patients, who carried half of DQ2.5 trans genotype.

CONCLUSIONS

Diagnostic yield of CD-related HLA testing varies widely depending on clinical indication. HLA testing is a practical and valuable test for most patients in whom initial evaluation for CD is inconclusive. A negative HLA result usually obviates the need for further celiac testing including endoscopy and gluten challenge. Rarely, in patients reported as HLA negative, half of HLA DQ2.5 (cis or trans) is sufficient for development of CD.

Risk of thyroid cancer in a nationwide cohort of patients with biopsy-verified celiac disease

BACKGROUND

In earlier studies based on selected populations, the relative risk for thyroid cancer in celiac disease has varied between 0.6 and 22.5. We aimed to test this relationship in a population-based setting.

METHODS

We collected small intestinal biopsy report data performed in 1969-2008 from all 28 Swedish pathology departments. 29,074 individuals with celiac disease (villous atrophy; Marsh histopathology stage III) were matched for sex, age, calendar year, and county to 144,440 reference individuals from the Swedish general population. Through Cox regression, we then estimated hazard ratios (HRs) and confidence intervals (CIs) for any thyroid cancer and papillary thyroid cancer (defined according to relevant pathology codes in the Swedish Cancer Register) in patients with celiac disease.

RESULTS

During follow-up, any thyroid cancer developed in seven patients with celiac disease (expected=12) and papillary thyroid cancer developed in five patients (expected=7). Celiac disease was not associated with an increased risk of any thyroid cancer (HR 0.6 [CI 0.3-1.3]) or of papillary thyroid cancer (HR 0.7 [CI 0.3-1.8]). All cases of thyroid cancer in celiac disease occurred in female patients. Risk estimates were similar before and after the year 2000 and independent of age at celiac diagnosis (≤24 years vs. ≥25 years).

CONCLUSIONS

We conclude that, in the Swedish population, there is no increased risk of thyroid cancer in patients with celiac disease. This differs from what has been reported in smaller studies in Italy and the United States.

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.

Frequency of celiac disease in patients with hypothyroidism

Background. Celiac disease (CD) is closely associated with other autoimmune endocrine disorders, particularly autoimmune thyroid disease. The aim of this study was to find the frequency of celiac disease in patients with hypothyroidism in Guilan province, north of Iran. Methods. A total of 454 consecutive patients with hypothyroidism underwent celiac serological tests antiGliadin antibodies (AGA), antitissue transglutaminase antibodies (IgA-tTG) and antiendomysial antibodies (EMA-IgA). Small intestinal biopsy was performed when any of celiac serological tests was positive. Results. Eleven (2.4%) patients were positive for celiac serology, and two patients with documented villous atrophy were diagnosed with classic CD (0.4%; 95%). Two patients with classic CD had Hashimoto's thyroiditis (HT) (0.6%; 95%). Six (54.5%) of 11 were suffering from overt hypothyroidism and 45.5% from subclinical hypothyroidism. Six (54.5%) had HT, and 45.5% had nonautoimmune hypothyroidism. Conclusions. In this study, prevalence of CD was lower than other studies. Most of the patients with CD were suffering from HT, but there was no significant statistical relation between CD and HT.

Celiac disease and hypothyroidism

BACKGROUND

Celiac disease is more common in patients with hypothyroidism. Malabsorption of levothyroxine has not been studied in this population. We sought to determine if levothyroxine dosing was influenced by the presence and treatment of celiac disease.

METHODS

This retrospective study was conducted at an academic medical center. Cases had hypothyroidism and celiac disease. Controls had hypothyroidism alone and were selected randomly through the endocrinology clinic records. Celiac disease was defined as representative pathology with positive serology. Age, sex, height, weight, body mass index, creatinine, and medical comorbidity were assessed for cases and controls. The levothyroxine dose and weight-based levothyroxine dose necessary to maintain a euthyroid state was evaluated for controls, and before and after celiac disease therapy for cases.

RESULTS

Celiac disease was identified in 152 patients, and 22 patients had concomitant hypothyroidism (14.5%). Seven cases met inclusion criteria. Overall, 200 control patients were identified. The mean celiac disease pretreatment levothyroxine dose and weight-based levothyroxine dose needed to maintain a euthyroid state were higher in cases than in controls (154 μg vs 106 μg, P=.007, and 2.6 μg/kg vs 1.3 μg/kg, P <.001). Doses decreased significantly after treatment of celiac disease (154 μg vs 111 μg, P=.03; and 2.64 μg/kg vs 1.89 μg/kg, P=.04). All cases required at least 125 μg of levothyroxine initially to maintain a euthyroid state.

CONCLUSIONS

Levothyroxine malabsorption likely occurs with hypothyroidism and untreated celiac disease. Absorption may improve after celiac disease treatment. Screening for celiac disease in patients with hypothyroidism requiring elevated levothyroxine doses warrants further investigation.

Tissue transglutaminase antibodies in individuals with celiac disease bind to thyroid follicles and extracellular matrix and may contribute to thyroid dysfunction

BACKGROUND

Individuals with active celiac disease (CD+) have an increased incidence of thyroid dysfunction, which improves on a gluten-free diet (CD-). We investigated whether tissue transglutaminase-2 IgA antibodies (anti-TGase II) present in sera of patients with celiac disease react with thyroid tissue and possibly contribute to thyroid disease.

METHODS

Serum from 40 active celiac patients taken before a gluten-free diet (CD+), 46 patients on a gluten-free diet (CD-), 40 normal controls (NC), and 25 with Crohn's disease (CROHN) was used. All sera were screened for antithyroperoxidase antibodies (TPO-AB) and thyroglobulin antibodies (TG-AB), and indirect immunofluorescence (IIF) was performed on primate thyroid tissue sections using TPO-AB- and TG-AB-negative sera.

RESULTS

IIF with thyroid seronegative, anti-TGase II-positive CD+ sera (n = 23) demonstrated staining of thyroid follicular cells and extracellular matrix, in an identical pattern with monoclonal anti-human TGase II antibody. Evidence of TGase II as the antigen in thyroid tissue was supported by elimination of the IIF pattern when sera were depleted of anti-TGase II by pretreatment with human recombinant TGase II. No staining of thyroid tissue was observed when sera from CD+ patients that were negative for TGase II antibodies, or sera from NC subjects were used. Thyroid antibodies were found in 43% of CD+ patients, significantly higher than NC and CROHN patients (p < 0.0001). In addition, a positive correlation was observed between anti-TGase II and TPO-AB titers (p = 0.0001; r = 0.63).

CONCLUSIONS

Anti-TGase II antibodies bind to TGase II in thyroid tissue, and titers correlate with TPO antibody titers. These findings suggest that anti-TGase II antibodies could contribute to the development of thyroid disease in celiac disease.

Thyroid-related autoantibodies in Tunisian patients with coeliac disease

BACKGROUND

The aim of our study was to evaluate, retrospectively, the frequency of anti-thyroid antibodies (ATA) in coeliac disease (CD) patients.

METHODS

ELISA was used to determine the frequency of anti-thyroid stimulating hormone receptor antibodies, thyroperoxidase antibodies and thyroglobulin antibodies in sera of 104 adult patients with CD. Patients were divided into three groups: group I, 56 untreated patients; group II, 21 patients on a strict gluten-free diet (GFD); and group III, 27 patients who did not comply with a GFD. Sera of 189 healthy blood donors served as controls.

RESULTS

Out of 104 patients with CD, five (4.8%) had ATA. The frequency of ATA found in the control group (1.6%) was not significantly different from that found in all CD patients. However, the frequency of ATA in CD patients on a GFD was significantly higher than that found in the control group (8.3% vs. 1.6%, p=0.03). The frequency of ATA in groups I, II and III was 1.8%, 9.5% and 7.4%, respectively.

CONCLUSIONS

ATA were found in CD patients even on a GFD.

Celiac disease and autoimmune thyroid disease

Celiac disease (CD) or gluten sensitive enteropathy is relatively common in western populations with prevalence around 1%. With the recent availability of sensitive and specific serological testing, many patients who are either asymptomatic or have subtle symptoms can be shown to have CD. Patients with CD have modest increases in risks of malignancy and mortality compared to controls. The mortality among CD patients who comply poorly with a gluten-free diet is greater than in compliant patients. The pattern of presentation of CD has altered over the past three decades. Many cases are now detected in adulthood during investigation of problems as diverse as anemia, osteoporosis, autoimmune disorders, unexplained neurological syndromes, infertility and chronic hypertransaminasemia of uncertain cause. Among autoimmune disorders, increased prevalence of CD has been found in patients with autoimmune thyroid disease, type 1 diabetes mellitus, autoimmune liver diseases and inflammatory bowel disease. Prevalence of CD was noted to be 1% to 19% in patients with type 1 diabetes mellitus, 2% to 5% in autoimmune thyroid disorders and 3% to 7% in primary biliary cirrhosis in prospective studies. Conversely, there is also an increased prevalence of immune based disorders among patients with CD. The pathogenesis of co-existent autoimmune thyroid disease and CD is not known, but these conditions share similar HLA haplotypes and are associated with the gene encoding cytotoxic T-lymphocyte-associated antigen-4. Screening high risk patients for CD, such as those with autoimmune diseases, is a reasonable strategy given the increased prevalence. Treatment of CD with a gluten-free diet should reduce the recognized complications of this disease and provide benefits in both general health and perhaps life expectancy. It also improves glycemic control in patients with type 1 diabetes mellitus and enhances the absorption of medications for associated hypothyroidism and osteoporosis. It probably does not change the natural history of associated autoimmune disorders.

Systemic autoimmune disorders in celiac disease

PURPOSE OF REVIEW

Celiac disease is an immune-mediated disorder clinically characterized by a multitude of symptoms and complications. The comorbidity between celiac disease and other autoimmune disorders has been clearly established.

RECENT FINDINGS

Two main theories have been postulated to explain this comorbidity: (1) linkage disequilibrium between the genes responsible for celiac disease and those responsible for the coexpressed autoimmune diseases or (2) untreated celiac disease leading to the onset of other autoimmune diseases. This article reviews the current literature supporting either theory and places the current knowledge in the field within the context of the most recent data on the pathogenesis of celiac disease.

SUMMARY

The current literature did not clearly establish which of the two theories explain the comorbidity between celiac disease and other autoimmune disorders. There is, however, growing evidence that the loss of the intestinal barrier function typical of celiac disease could be responsible of the onset of other autoimmune disease. This concept implies that the autoimmune response can be theoretically stopped and perhaps reversed if the interplay between autoimmune predisposing genes and trigger(s) is prevented or eliminated by a prompt diagnosis and treatment.

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.

Thyroid disorders in Brazilian patients with celiac disease

INTRODUCTION/AIM

Patients with celiac disease (CD) can develop a gluten related autoimmune disorder that affects not only the small intestine but other tissues as well. An increased prevalence of autoimmune diseases has been reported, particularly autoimmune thyroiditis. The aim of this study was to characterize thyroid disorders in patients with CD.

PATIENTS/METHODS

Fifty-two patients with CD (43 female, 9 male; mean age, 41.1 years) were studied. Nine were on a gluten-free diet (GFD). They were divided into four groups: Group 1, without thyroid involvement (n=30); Groups 2A-C, with thyroid involvement (n=22); Group 2A, subclinical hypothyroidism (n=11); Group 2B, clinical hypothyroidism (n=10); and Group 2C, other thyroid disorders (n=1). CD was confirmed by serologic and histologic criteria. Thyroid involvement was detected by measurement of thyroid stimulating hormone (TSH) and anti-thyroperoxidase antibodies (anti-TPO).

RESULTS

Increased levels of TSH and/or anti-TPO levels were detected in Groups 2A (21.1%) and 2B (19.2%). The patients of Group 2B presented clinical symptoms of hypothyroidism before the diagnosis of CD, and 5 of these patients were receiving levothyroxine. One woman (Group 2C; 1.92%) had a medullary carcinoma. There was statistical significance between the age when thyroid disease was diagnosed (current age) and the age of CD diagnosis between Groups 1 and 2B. Patients with thyroid involvement presented associated diseases such as diabetes mellitus (2), Down's syndrome (2), ulcerative colitis (1), and dermatitis herpetiformis (2).

CONCLUSIONS

Our findings demonstrated an increased prevalence of thyroid disorders (hypothyroidism, 19.2%; and subclinical hypothyroidism, 21.2%), and other associated diseases in celiac patients, even on a GFD, increasing with the age of the patients. Screening for associated diseases is recommended for patients with CD, independent of age at diagnosis or treatment duration.

Celiac sprue (the great modern-day imposter)

PURPOSE OF REVIEW

To review the current epidemiological information on celiac disease and the various presentations and associated.

RECENT FINDINGS

Epidemiologic studies reveal celiac disease to be common, occurring in approx. 1% of the population. It is being diagnosed worldwide, even in developing countries. The classic mode of presentation has become less common, with diarrhea or a malabsorption syndrome as the mode of presentation in fewer than 50% of individuals. The other major modes of presentation are iron-deficiency anemia, osteoporosis, screening of family members, or incidentally at endoscopy done for dyspepsia or reflux. Neurological presentations may include peripheral neuropathy or ataxia. Arthritis is commonly found in patients with celiac disease when systematically sought. Patients often have a previous diagnosis of irritable bowel syndrome. Autoimmune diseases occur more frequently (three to ten times more) in those with celiac disease than the general population. However, this increased incidence of autoimmune diseases is not prevented by early diagnosis of celiac disease.

SUMMARY

We will review the various associated diseases/presentations of celiac disease. The heterogeneity of the symptoms can make the diagnosis challenging and certainly the great modern-day imposter.

Prospective screening for coeliac disease in patients with Graves' hyperthyroidism using anti-gliadin and tissue transglutaminase antibodies

INTRODUCTION

Coeliac disease (CD) is associated with autoimmune thyroid disease (AITD) although its prevalence among those with Graves' hyperthyroidism in the UK is unknown. We determined the prevalence and evaluated the role of screening for CD prospectively in a consecutive cohort of patients with Graves' hyperthyroidism using IgA class antibodies to gliadin (AGA) and tissue transglutaminase (anti-tTG).

METHODS

All patients with Graves' hyperthyroidism attending the thyroid clinic over a 9-month period were offered screening for CD using AGA (normal < 3 mg/l) and anti-tTG (normal < 15 micro/ml). Comparison was made with an age- and sex-matched healthy control group from the local population whose sera were tested for anti-tTG. In patients with borderline or raised anti-tTG (> 7 micro/ml) endomysial antibody (EmA) was measured. Serum IgA was also measured to exclude IgA deficiency. Patients with raised AGA, raised or borderline anti-tTG, positive EmA, IgA deficiency or haematinic deficiencies were offered endoscopic duodenal biopsy.

RESULTS

A total of 115 patients (97 female and 18 male) with Graves' hyperthyroidism were offered screening tests and 111 accepted. AGA was raised in 15 patients, anti-tTG was raised in two (both positive for EmA) and equivocal in six (one positive for EmA). IgA deficiency was present in three. Four patients were known to have haematinic deficiencies. Twenty-five patients were invited and 19 agreed to have endoscopic duodenal biopsy. Three new patients were found to have CD while two patients were already known to have CD, thus five of 111 patients with Graves' hyperthyroidism had CD. One of 115 healthy controls had a strong positive anti-tTG (> 200 micro/ml) and EmA indicating probable CD.

CONCLUSIONS

Screening 111 consecutive patients with Graves' hyperthyroidism revealed AGA in 14%, anti-tTG in 2% and IgA deficiency in 3%. Two patients were known to have CD. Screening detected three new cases. The prevalence of CD in patients with Graves' hyperthyroidism was 4.5% as compared with 0.9% in matched healthy controls. Routine screening for CD should be considered.

Narrative review: celiac disease: understanding a complex autoimmune disorder

Celiac disease is a common autoimmune disorder that has genetic, environmental, and immunologic components. It is characterized by an immune response to ingested wheat gluten and related proteins of rye and barley that leads to inflammation, villous atrophy, and crypt hyperplasia in the intestine. The disease is closely associated with genes that code for human leukocyte antigens DQ2 and DQ8. Transglutaminase 2 appears to be an important component of the disease, both as a deamidating enzyme that can enhance the immunostimulatory effect of gluten and as a target autoantigen in the immune response. Sensitive and specific serologic tests, including those for anti-transglutaminase antibody, are facilitating fast and noninvasive screening for celiac disease. Thus, they are contributing to a more accurate estimate of the prevalence of the disease and its association with other disorders. Celiac disease is associated with increased rates of anemia, osteoporosis, cancer, neurologic deficits, and additional autoimmune disorders. A gluten-free diet is the mainstay of safe and effective treatment of celiac disease, although its effect on some of the extraintestinal manifestations of the disease remains to be determined.