The Brazilian consensus for the diagnosis and treatment of hyperthyroidism: recommendations by the Thyroid Department of the Brazilian Society of Endocrinology and Metabolism

Low-iodine diet: what to eat and avoid before iodine-131 procedures?

OBJECTIVE

The aim of this study was to compile a list of low-iodine foods for use in the Low-Iodine Diet (LID) to optimize the uptake of Iodine-131 by cells, which is used in the diagnosis and treatment of thyroid gland disorders.

METHODS

A bibliographic research was conducted focusing on the most commonly consumed foods in Brazil. Iodine quantification was derived from both national and international food composition tables, with an emphasis on sources indicating the highest concentrations of this microelement. The foods were organized into categories, and their iodine levels were presented in micrograms per 100 grams of food.

RESULTS

The compiled list includes foods classified into categories such as cereals, legumes, vegetables, fruits, flours, oils, fats, meats, dairy products, and beverages. Foods with more than 50 μg of iodine per 100 g were identified and classified separately. Based on the findings, marine-derived foods should be avoided, while dairy products and eggs can be consumed, provided substitutions are made.

CONCLUSION

Identifying and quantifying low-iodine foods is essential for guiding the LID, making it more effective and better suited to the population's needs. Legumes, vegetables, and most fruits can be consumed in larger quantities, forming the core of the diet.

A systematic review of guidelines on screening for celiac disease in children with thyroid disease and vice versa

Introduction

Autoimmune thyroid diseases (ATD) are the most prevalent autoimmune disorders associated with celiac disease (CD). Both conditions can often be detected through serological screening in asymptomatic patients over several years. Various guidelines for screening thyroid disease (TD) are available in children with CD and vice versa.

Methods

We conducted a systematic review to identify the most recent and relevant guidelines, comparing their recommendations to analyze key differences and suggesting a practical clinical approach.

Results

Out of 1,294 articles reviewed, we identified 20 guidelines published between January 2013 and January 2024. These guidelines, primarily from gastroenterological organizations in Europe and North America, recommend different timings and methods for screening the co-occurrence of these diseases, both at diagnosis and during follow up. Some guidelines recommend only clinical follow-up without routine serological screening. There is limited consensus on screening for TD [using thyroid-stimulating hormone test (TSH)] in asymptomatic children newly diagnosed with CD, and even less agreement on screening for CD [using anti-transglutaminase antibodies (tTG) immunoglobulin A (IgA) test and total IgA] in children newly diagnosed with TD. No standardized procedures exist for managing patients with isolated low tTG and human leukocyte antigen (HLA) genotyping is rarely recommended as a first- line screening method.

Discussion

Over the past decade, there has been a growing recognition of the importance of identifying children with co-occurrence of CD and TD who could benefit from early treatment, even in the absence of symptoms. However, international guidelines still show a lack of consensus regarding screening for these frequently associated autoimmune diseases, with notable differences in the use of HLA testing and follow-up protocols.

Treatment of Graves' disease in Brazil: results of a survey among endocrinologists

Objective

The objective of the study was to determine how physicians in Brazil manage Graves' disease in different scenarios including extrathyroidal manifestations.

Materials and methods

This study was conducted via a digital survey. The respondents (n = 573) answered multiple-choice questions based on a clinical case and variations of the case regarding laboratory and imaging evaluation, treatment choice, and follow-up.

Results

The preferred initial treatment chosen by 95% of the respondents was ATD with a preferred treatment duration of 18-24 months. For 5% of the respondents, RAI was the initial treatment of choice. None of the respondents chose thyroidectomy. When presented with a patient with a desire for pregnancy in the near future, most respondents (69%) opted for ATD as the initial treatment. For a patient with signs of mild to moderate Graves' orbitopathy, ATD remained the initial therapy for 93.9% of the respondents. For patients initially treated with ATD with disease recurrence after ATD interruption, most respondents (60%) chose definitive treatment with RAI. A similar survey published in 2011 by Burch and cols. had results comparable to those of the present survey but with a higher proportion of respondents choosing RAI (45% in the 2011 survey versus 5% in the present survey).

Conclusion

Brazilian endocrinologists choose ATD as the initial management of Graves' disease, and most choose RAI as a definitive treatment for a patient with relapse after ATD therapy.

Perioperative management of the thyrotoxic patients: A systematic review

Background

Thyrotoxicosis is a clinical syndrome produced by a multitude of disorders. Thyrotoxicosis is a serious medical condition that, if left untreated, can lead to a fatal illness. This review of recent evidences give additional input for perioperative management of thyrotoxic patients.

Methods

The literatures were found with Boolean operators in the form of thyrotoxicosis AND anesthesia, antithyroid medications AND perioperative optimization AND beta blockers OR calcium channel blockers in electronic data base sources such as the Cochrane library, PubMed, and Google scholar. This review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement.

Conclusions

and recommendations: Before surgery and anesthesia, manifestation of thyrotoxicosis including palpitation, irritability etc should be ruled out.

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Thyrotoxicosis is a clinical syndrome produced by a multitude of disorders.

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Hyperthyroidism is a prevalent clinical condition that raises the risk of complications.

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Surgery and anesthesia should be postponed in elective thyrotoxicosis patients.

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Patients with thyrotoxicosis symptoms and elevated thyroid function tests should be optimized for 12–18 months.

Amiodarone-Induced Thyrotoxicosis - Literature Review & Clinical Update

Amiodarone is widely used in treating atrial and ventricular arrhythmias; however, due to its high iodine concentration, the chronic use of the drug can induce thyroid disorders. Amiodarone-induced thyrotoxicosis (AIT) can decompensate and exacerbate underlying cardiac abnormalities, leading to increased morbidity and mortality, especially in patients with left ventricular ejection fraction <30%. AIT cases are classified into two subtypes that guide therapeutic management. The risks and benefits of maintaining the amiodarone must be evaluated individually, and the therapeutic decision should be taken jointly by cardiologists and endocrinologists. Type 1 AIT treatment is similar to that of spontaneous hyperthyroidism, using antithyroid drugs (methimazole and propylthiouracil) at high doses. Type 1 AIT is more complicated since it has proportionally higher recurrences or even non-remission, and definitive treatment is recommended (total thyroidectomy or radioiodine). Type 2 AIT is generally self-limited, yet due to the high mortality associated with thyrotoxicosis in cardiac patients, the treatment should be implemented for faster achievement of euthyroidism. Furthermore, in well-defined cases of type 2 AIT, the treatment with corticosteroids is more effective than treatment with antithyroid drugs. In severe cases, regardless of subtype, immediate restoration of euthyroidism through total thyroidectomy should be considered before the patient progresses to excessive clinical deterioration, as delayed surgery indication is associated with increased mortality.

Management of thyroid disorders during the COVID-19 outbreak: a position statement from the Thyroid Department of the Brazilian Society of Endocrinology and Metabolism (SBEM)

This position statement was prepared to guide endocrinologists on the best approach to managing thyroid disorders during the coronavirus disease (COVID-19) pandemic. The most frequent thyroid hormonal findings in patients with COVID-19, particularly in individuals with severe disease, are similar to those present in the non-thyroidal illness syndrome and require no intervention. Subacute thyroiditis has also been reported during COVID-19 infection. Diagnosis and treatment of hypothyroidism during the COVID-19 pandemic may follow usual practice; however, should avoid frequent laboratory tests in patients with previous controlled disease. Well-controlled hypo and hyperthyroidism are not associated with an increased risk of COVID-19 infection or severity. Newly diagnosed hyperthyroidism during the pandemic should be preferably treated with antithyroid drugs (ATDs), bearing in mind the possibility of rare side effects with these medications, particularly agranulocytosis, which requires immediate intervention. Definitive treatment of hyperthyroidism (radioiodine therapy or surgery) may be considered in those cases that protective protocols can be followed to avoid COVID-19 contamination or once the pandemic is over. In patients with moderate Graves' ophthalmopathy (GO) not at risk of visual loss, glucocorticoids at immunosuppressive doses should be avoided, while in those with severe GO without COVID-19 and at risk of vision loss, intravenous glucocorticoid is the therapeutic choice. Considering that most of the thyroid cancer cases are low risk and associated with an excellent prognosis, surgical procedures could and should be postponed safely during the pandemic period. Additionally, when indicated, radioiodine therapy could also be safely postponed as long as it is possible.

Polymorphisms of the genes CTLA4, PTPN22, CD40, and PPARG and their roles in Graves' disease: susceptibility and clinical features

PURPOSE

CTLA4, PTPN22, and CD40 are immune-regulatory genes strongly associated with GD, as well as PPARG, but their clinical significance in different populations is still uncertain.

METHODS

We genotyped 282 Brazilian GD patients (234 women and 48 men, 39.80 ± 11.69 years old), including 144 patients with GO, and 308 healthy control individuals (246 women and 62 men, 36.86 ± 12.95 years old).

RESULTS

A multivariate analysis demonstrated that the inheritance of the GG genotype rs3087243 of CTLA4 (OR = 2.593; 95% CI = 1.630-4.123; p < 0.0001) and the CC genotype of rs3789607 of PTPN22 (OR = 2.668; 95% CI = 1.399-5.086; p = 0.0029) consisted in factors independent of the susceptibility to GD. The inheritance of polymorphic genotypes of rs5742909 of CTLA4 was associated with older age at the time of diagnosis (42.90 ± 10.83 versus 38.84 ± 11.81 years old; p = 0.0105), with higher TRAb levels (148.17 ± 188.90 U/L versus 112.14 ± 208.54 U/L; p = 0.0229) and the need for higher therapeutic doses of radioiodine (64.23 ± 17.16 versus 50.22 ± 16.86; p = 0.0237). The inheritance of the CC genotype of rs1883832 CD40 gene was more frequent among women (69.65%) than men (52.00%; p = 0.0186). The polymorphic genotype of PPARG gene (rs1801282) was associated with TPOAb positivity (p = 0.0391), and the GG genotype of rs2476601 of PTPN22 gene was associated with positivity for both TgAb (p = 0.0360) and TPOAb (p < 0.0001). Both polymorphic genotypes rs2476601 and rs3789607 of the PTPN22 gene were more frequent among nonsmoking patients (p = 0.0102 and p = 0.0124, respectively).

CONCLUSIONS

Our data confirm the important role of CTLA4 polymorphisms in GD susceptibility; demonstrate the role of PTPN22 polymorphisms in patients' clinical features; and suggest these genes may influence the severity of the disease.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Increased cytokines production and oxidative stress are related with purinergic signaling and cell survival in post-thyroidectomy hypothyroidism

Thyroid hormones have essential roles in regulation of cellular functions, including the immune system. The purinergic signaling, activated through extracellular nucleotides and nucleosides has also strong implications in immune response regulation. Hypothyroidism may involve effects on the immune and purinergic systems. In view of that, we evaluated cytokines levels, their relation with the expression of purinergic enzymes and the effects of this condition on immune system cells from patients with post-thyroidectomy hypothyroidism. Increased IL6, IL10, IL17 and TNF-α levels as well as an increase in CD73 expression in lymphocytes were observed in patients' blood. Moreover, augmented myeloperoxidase activity, lipid peroxidation and thiolgroup production were observed in post-thyroidectomy hypothyroidism. In addition, proliferation and cell death of lymphocytes were enhanced when exposed to patients' serum. This study demonstrates that hypothyroidism is related to changes in the purinergic system, increased cytokines production and oxidative stress, which interfere in the cell life and signaling.

Contribuições da vitamina D no tratamento de sintomas depressivos e fatores de risco cardiovascular: protocolo de estudo para um ensaio clínico randomizado, duplo-cego e controlado por placebo

ABSTRATO

FUNDO: A depressão é uma das principais causas de incapacidade crônica em todo o mundo e um importante fator de risco cardiovascular, aumentando o risco relativo de doença arterial coronariana, bem como as taxas de morbimortalidade cardiovascular. Concomitantemente à alta prevalência de depressão, houve uma redução na exposição à luz solar com o aumento da urbanização e do uso de protetores solares, o que levou a uma redução nos níveis séricos de 25-hidroxivitamina D. Portanto, este artigo descreve uma protocolo para um ensaio clínico com o objetivo de avaliar os efeitos da suplementação de vitamina D na depressão e fatores de risco cardiovascular para contribuir com evidências sobre a influência potencial da suplementação na regulação do humor. MéTODOS: Este estudo de protocolo foi orientado pelos itens de protocolo padrão: recomendações para ensaios intervencionistas. Um ensaio clínico randomizado, controlado por placebo, duplo-cego será realizado envolvendo 224 adultos (faixa etária de 18 a 60 anos) com depressão que estão tomando antidepressivos e não têm histórico de suplementação de vitamina D, comorbidades psiquiátricas, doença renal crônica, hipercalcemia, ou neoplasia. Os participantes serão recrutados nos ambulatórios psiquiátricos de duas universidades do nordeste do Brasil. Os participantes elegíveis que fornecerem consentimento por escrito serão designados aleatoriamente para o grupo de intervenção (n = 112; suplementação de vitamina D 50.000 UI por semana durante 6 meses) ou para o grupo controle (n = 112; placebo tomado semanalmente por 6 meses). Medidas para monitorar sintomas depressivos, exames clínicos e exames laboratoriais para avaliar fatores de risco cardiovascular e níveis séricos de vitamina D serão realizadas antes e após o período de intervenção. DISCUSSãO: Até onde sabemos, este será o primeiro ensaio clínico com o objetivo de testar a eficácia da suplementação de vitamina D na redução do risco cardiovascular e como um adjuvante à terapia da depressão por um período prolongado (6 meses). Os resultados contribuirão para a compreensão dos efeitos terapêuticos da suplementação de vitamina D no tratamento da depressão e podem ajudar a orientar políticas públicas direcionadas à suplementação de vitamina para a redução do risco cardiovascular.

REGISTRO DE TESTE

Registro Brasileiro de Ensaios Clínicos, RBR-6yj8sj/ Número Universal de Ensaios (UTN) U1111-1217-9237 . Registrado em 23 de julho de 2018.

How do paediatricians use and monitor antithyroid drugs in the UK? A clinician survey

OBJECTIVE

We aimed to document current practice in the medical management of paediatric hyperthyroidism in the UK and compare to international recommendations.

DESIGN

A 27-question online survey distributed via an electronic newsletter in August 2018.

PARTICIPANTS

Responses from 48 members (11%) of the British Society for Paediatric Endocrinology and Diabetes.

MEASUREMENTS

Information about antithyroid drug (ATD) preference, treatment duration, monitoring of full blood count (FBC), management of neutropaenia, agranulocytosis screening and patient education.

RESULTS

Carbimazole is favoured by 98% of respondents and a "dose titration" regimen preferred over "block and replace" (65% vs 29%). TRAbs (thyroid-stimulating hormone receptor antibodies) are used for diagnostic purposes by 85% and by 33% to look for evidence of disease remission. The majority (81%) treat for a minimum of 2 years before considering a trial off ATD. All respondents reported that they "always/usually" warn their patients about the risk of agranulocytosis before starting ATD, but written information is "rarely/never" provided by 63%. Sore throat (98%) and fever (92%) are the most commonly cited symptoms used to alert a patient to possible agranulocytosis. FBC is measured prior to treatment by 65% and measured periodically during treatment by 70%.

CONCLUSIONS

The management of paediatric hyperthyroidism with ATDs in the UK is not consistent with all international recommendations because a block and replace ATD regimen remains widely used. TRAbs are utilized at presentation, but underused for detecting disease remission. National consensus guidelines and written patient information may refine the management of paediatric patients on ATDs.

Value of Infrared Thermography Camera Attached to a Smartphone for Evaluation and Follow-up of Patients with Graves' Ophthalmopathy

PURPOSE

Graves' ophthalmopathy (GO) is the most common extra-thyroid manifestation of Graves' disease (GD). The Clinical Activity Score (CAS) has been widely used to evaluate GO inflammation severity and response to treatment; however, it is quite subjective. Infrared thermography (IRT) is a portable and low-cost device to evaluate local temperature and assess inflammation. The aim was to evaluate ocular temperature by IRT as an instrument for measuring inflammatory activity in GO and its correlation with CAS.

METHODS

This is a cross-sectional study involving 136 consecutive GD patients (12 with CAS ≥ 3/7, 62 with CAS < 3 and 62 without apparent GO) with 62 healthy controls. Patients with active ophthalmopathy were prospectively evaluated. Exophthalmometry, CAS, and thermal images from caruncles and upper eyelids were acquired from all subjects.

RESULTS

All eye areas of thermal evaluation had higher temperatures in GD patients with active ophthalmopathy (caruncles, p<0.0001; upper eyelids, p<0.0001), and it was positively correlated with CAS (r=0.60 and p<0.0001 at caruncles; r=0.58 and p<0.0001 at upper eyelids). No difference in temperature was found between other groups. Patients with active ophthalmopathy were prospectively evaluated after 6 or 12 months of the treatment and a significant difference was found in ophthalmometry (p=0.0188), CAS (p=0.0205), temperature of caruncles (p=0.0120), and upper eyelids (p=0.0066).

CONCLUSIONS

IRT was an objective and simple tool for evaluation and follow-up of inflammation in GO, allowed evidencing patients with significant inflammatory activity, and had a good correlation with the CAS score.

Antithyroid drug therapy in pregnancy: a review of guideline recommendations

The antithyroid drugs, Carbimazole, Methimazole, and Propylthiouracil remain the mainstay of Graves' disease management in pregnancy. A series of Clinical Practice Guidelines aimed at optimising fetal and maternal outcomes in women with Graves' disease have been published in recent years. Areas covered: This review examines existing guideline recommendations on antithyroid drug management of Graves' disease in pregnancy. Expert commentary: Recent guidelines have been shaped by expanding knowledge of the adverse effect profiles of antithyroid drugs on the developing fetus. A core management strategy is to limit fetal exposure to excess thyroid hormones and to curtail adverse drug effects through effective preconception and peri-conception management. Propylthiouracil is the recommended treatment in the first trimester of pregnancy but there is uncertainty regarding antithyroid drug choices in women who continue to require treatment in later pregnancy. Further studies are needed to fully evaluate the risks of congenital anomalies following intrauterine thionamide exposure.

Guidelines for the treatment of childhood-onset Graves' disease in Japan, 2016

Purpose behind developing these guidelines: Over one decade ago, the “Guidelines for the Treatment of Graves’ Disease with Antithyroid Drug, 2006” (Japan Thyroid Association (JTA)) were published as the standard drug therapy protocol for Graves’ disease. The “Guidelines for the Treatment of Childhood-Onset Graves’ Disease with Antithyroid Drug in Japan, 2008” were published to provide guidance on the treatment of pediatric patients. Based on new evidence, a revised version of the “Guidelines for the Treatment of Graves’ Disease with Antithyroid Drug, 2006” (JTA) was published in 2011, combined with the “Handbook of Radioiodine Therapy for Graves’ Disease 2007” (JTA). Subsequently, newer findings on pediatric Graves’ disease have been reported. Propylthiouracil (PTU)-induced serious hepatopathy is an important problem in pediatric patients. The American Thyroid Association’s guidelines suggest that, in principle, physicians must not administer PTU to children. On the other hand, the “Guidelines for the Treatment of Graves’ Disease with Antithyroid Drug, 2011” (JTA) state that radioiodine therapy is no longer considered a “fundamental contraindication” in children. Therefore, the “Guidelines for the Treatment of Childhood-Onset Graves’ Disease with Antithyroid Drug in Japan, 2008” required revision.

Hyperthyroidism

Hyperthyroidism is characterised by increased thyroid hormone synthesis and secretion from the thyroid gland, whereas thyrotoxicosis refers to the clinical syndrome of excess circulating thyroid hormones, irrespective of the source. The most common cause of hyperthyroidism is Graves' disease, followed by toxic nodular goitre. Other important causes of thyrotoxicosis include thyroiditis, iodine-induced and drug-induced thyroid dysfunction, and factitious ingestion of excess thyroid hormones. Treatment options for Graves' disease include antithyroid drugs, radioactive iodine therapy, and surgery, whereas antithyroid drugs are not generally used long term in toxic nodular goitre, because of the high relapse rate of thyrotoxicosis after discontinuation. β blockers are used in symptomatic thyrotoxicosis, and might be the only treatment needed for thyrotoxicosis not caused by excessive production and release of the thyroid hormones. Thyroid storm and hyperthyroidism in pregnancy and during the post-partum period are special circumstances that need careful assessment and treatment.

Methimazole discontinuation before radioiodine therapy in patients with Graves' disease

INTRODUCTION

Although radioiodine therapy (RIT) has been used for the treatment of hyperthyroidism for many decades, there is no consensus on the optimal time of methimazole (MMI) discontinuation before RIT. The aim of this clinical trial is to study the effect of three different time points of MMI discontinuation on response to RIT.

METHOD AND PATIENTS

Overall, 151 patients (18-65 years old), with Graves' disease who were taking MMI and referred to I-131 therapy, were consecutively assigned to one of three groups, and MMI was discontinued for 24-48, 48.1-72, and 72.1-168 h in group, 1, 2, and 3, respectively. Radioiodine uptake was measured in all patients and the radioiodine dose was calculated according to the Quimby formula to deliver 7.4 MBq of I-131 per gram of thyroid weight. Response to RIT was assessed at 1, 3, 6, and 12 months after RIT.

RESULTS

A total of 102 women and 49 men were included in the study. The mean administered dose of I-131 was 362.9±188.7 MBq (9.8±5.1 mCi) and the mean time to response for radioiodine was 4.1±3.6 months. There was no significant difference between the three groups in age, thyroid weight, anti-TPO level, radioactive iodine uptake level, and radioiodine dose (P>0.1). Response to RIT at 1, 3, 6, and 12 months after administration was also not different between the three groups (P>0.57).

CONCLUSION

No difference was found in the response to treatment between patients with MMI discontinuation for 24-48, 48.1-72, and 72.1-96 h before RIT. Shorter discontinuation of MMI before RIT may be preferable in most patients. Video Abstract: http://links.lww.com/NMC/A39.

TSHR intronic polymorphisms (rs179247 and rs12885526) and their role in the susceptibility of the Brazilian population to Graves' disease and Graves' ophthalmopathy

PURPOSE

Intronic thyroid-stimulating hormone receptor polymorphisms have been associated with the risk for both Graves' disease and Graves' ophthalmopathy, but results have been inconsistent among different populations. We aimed to investigate the influence of thyroid-stimulating hormone receptor intronic polymorphisms in a large well-characterized population of GD patients.

METHODS

We studied 279 Graves' disease patients (231 females and 48 males, 39.80 ± 11.69 years old), including 144 with Graves' ophthalmopathy, matched to 296 healthy control individuals. Thyroid-stimulating hormone receptor genotypes of rs179247 and rs12885526 were determined by Real Time PCR TaqMan(®) SNP Genotyping.

RESULTS

A multivariate analysis showed that the inheritance of the thyroid-stimulating hormone receptor AA genotype for rs179247 increased the risk for Graves' disease (OR = 2.821; 95 % CI 1.595-4.990; p = 0.0004), whereas the thyroid-stimulating hormone receptor GG genotype for rs12885526 increased the risk for Graves' ophthalmopathy (OR = 2.940; 95 % CI 1.320-6.548; p = 0.0083). Individuals with Graves' ophthalmopathy also presented lower mean thyrotropin receptor antibodies levels (96.3 ± 143.9 U/L) than individuals without Graves' ophthalmopathy (98.3 ± 201.9 U/L). We did not find any association between the investigated polymorphisms and patients clinical features or outcome.

CONCLUSION

We demonstrate that thyroid-stimulating hormone receptor intronic polymorphisms are associated with the susceptibility to Graves' disease and Graves' ophthalmopathy in the Brazilian population, but do not appear to influence the disease course.