Hyperthyroidism Prevalence in China After Universal Salt Iodization.

Background: Universal salt iodization (USI) was implemented in mainland China in 1996. The prevalence of hyperthyroidism and its risk factors now require examination. Methods: Data were acquired from a nationwide Thyroid, Iodine, and Diabetes Epidemiological survey (TIDE 2015-2017) of 78,470 subjects from 31 provinces. Iodine status, and thyroid hormones and antibodies were measured. Results: After two decades of USI, the prevalence of overt hyperthyroidism (OH), Graves' disease (GD), severe subclinical hyperthyroidism (severe SCH), and mild subclinical hyperthyroidism (mild SCH) in mainland China was 0.78%, 0.53%, 0.22%, and 0.22%, respectively. OH and GD prevalence were higher in women than in men (OH: 1.16% vs. 0.64%, P<0.001; GD: 0.65% vs. 0.37%, P<0.001).Prevalence was significantly decreased after 60 years-of-age compared with 30-39 years-of-age (OH:0.61% vs. 0.81%, P<0.001; GD: 0.38% vs. 0.57%, P<0.001).Excessive iodine(EI) and deficient iodine(DI) were both related to increased prevalence of OH (odds ratio [OR] 2.09, 95% confidence interval [CI] 1.68-2.59; OR1.35, 95%CI 1.07-1.72, respectively); however, only deficient iodine was associated with increased prevalence of GD (OR1.67, 95%CI 1.30-2.15). Increased thyroid peroxidase antibody and thyroglobulin antibody levels were significantly associated with prevalence of OH and GD, but not severe SCH and mild SCH. Although hyperthyroidism was more prevalent in women, the association disappeared after adjusting for other factors such as antibody levels. Conclusion: OH and GD prevalences in mainland China are stable after two decades of USI. Iodine deficiency, elevated thyroid antibody levels, and middle age are the main risk factors for OH and GD. The severe SCH population, rather than the mild SCH population, shows similar characteristics to the OH population.

Pembrolizumab-Induced Thyroiditis.

Immune checkpoint inhibitors act to restore T cell-mediated antitumor immunity. By this nature, these cancer immunotherapy drugs are associated with various immune-related adverse events such as thyroid dysfunction. We describe a case of thyrotoxicosis secondary to a programmed cell death 1 (PD-1) immune checkpoint inhibitor, pembrolizumab. A 30-year-old female was started on pembrolizumab immunotherapy for stage III small cell carcinoma of the ovary, hypercalcemic type. Thirteen days after her second cycle of therapy, she presented with symptoms consistent with thyrotoxicosis. A thyroiditis was diagnosed by thyroid function tests and ultrasonography. She was originally treated with prednisone and metoprolol for possible Grave's disease. Pertechnetate thyroid scan was more consistent with thyroiditis secondary to pembrolizumab. She underwent a total thyroidectomy 10 days after initial presentation for refractory thyrotoxicosis despite maximal medical therapy. Her symptoms resolved and thyroid function tests significantly improved. Pathology was consistent with severe thyroiditis. Immune microenvironment may play a role in the expression of programmed cell death protein 1 ligand 1 (PD-L1). Chronic inflammation surrounding tumor upregulates PD-L1 expression on tumor cells by the release of cytokines, which acts to inhibit tumor destruction. We suggest that our patient had an undetected chronic inflammation of the thyroid, specifically Hashimoto's thyroidits, which predisposed her to thyroid destruction when taking pembrolizumab. Understanding that an inflammatory environment impacts thyroid toxicity to PD-1 inhibitor therapy is novel and should be further studied.

Does Immunosuppressive Therapy Improve Outcomes in Graves' Disease? A Systematic Review and Meta-Analysis.

BACKGROUND: Whether the addition of immunosuppressive drugs to standard antithyroid drugs reduces the relapse risk in Graves' disease remains uncertain. PURPOSE: The aim of this study was to investigate the effects of immunosuppressive drugs on the relapse rate after a first episode of hyperthyroidism due to Graves' disease. METHODS: Based on a pre-specified protocol, PubMed (1946-July 2015), EMBASE (1947-July 2015), and Cochrane (1992-July 2015) databases were searched. The search was for (randomized) controlled trials comparing immunosuppressive drugs with a control group. PRISMA and SIGN statements were used for assessing data quality. Two reviewers extracted data, with any disagreement being resolved by consensus. Data were pooled using a random-effects model. RESULTS: The primary endpoint was relapse of disease until follow-up. Secondary endpoints included reduction of thyroid volume and decrease in thyrotropin-receptor antibody (TRAb) levels. Seven trials with 862 participants were included. Most trials were small with a moderate to high risk of bias. There were 113 relapses in 481 (23.5%) patients receiving immunosuppressive drugs compared with 225 relapses in 381 (59.1%) control patients (risk ratio for recurrence 0.55; [confidence interval (CI) 0.41-0.75]). Subgroup analyses showed similar effects for randomized trials and controlled trials (I(2) 0%), and for trials using corticosteroid and non-corticosteroid immunosuppressive drugs (I(2) 0%). Use of immunosuppressive drugs also resulted in significant reductions in thyroid volume (-10.72 mL [CI -15.59 to -5.85]) and TRAb levels (-17.01 IU/L [CI -33.31 to -0.72]). Immunosuppressive drug-related adverse effects were not systematically reported, and thus were not included in the quantitative analysis. CONCLUSIONS: Current evidence suggests a possible relevant reduction in relapse risk when immunosuppressive drugs are added to standard treatment of Graves' disease. The small number of trials with high heterogeneity in regard to treatment modalities and the lack of systematic reporting of adverse effects calls for larger, conclusive trials.

Induction of thyroid remission using rituximab in a patient with type 3 autoimmune polyglandular syndrome including Graves' disease and type 1 diabetes mellitus: a case report.

Rituximab (RTX) is a monoclonal antibody that targets the B-cell-specific CD20 antigen. Recent reports indicate that RTX is effective against type 1 diabetes mellitus (T1DM) and hematologic as well as autoimmune diseases. Other studies have indicated that RTX therapy leads to the remission of recurrent or active Graves' disease (GD). However, the efficacy of RTX in Japanese patients with autoimmune polyglandular syndrome (APS) has not been reported to date. Herein, we report the case of a patient with GD and T1DM with sustained endogenous insulin secretion capacity. To protect pancreatic ß cells, we administered RTX at a dose of 500 mg (approximately 300 mg/m2) on 2 occasions 1 week apart. After treatment, no adverse effects were observed, and thyroid stimulating hormone receptor antibody (TRAb) was no longer detectable 4 months after RTX administration. In addition, the reduction in TRAb level improved thyroid function. Notably, the treatment induced remission over a period of 1 year after the diagnosis of GD.

Graves' hyperthyroidism and moderate alcohol consumption: evidence for disease prevention.

BACKGROUND: We recently demonstrated that moderate alcohol consumption is associated with a considerable reduction in the risk of autoimmune hypothyroidism, similar to findings in other autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. We aimed to study a possible association between alcohol intake and autoimmune Graves' hyperthyroidism. DESIGN: This is a population-based, case-control study. METHODS: In a well-defined Danish population (2,027,208 person-years of observation), we prospectively identified patients with new overt thyroid dysfunction and studied 272 patients with Graves' hyperthyroidism. For each patient, we recruited four age-gender-region-matched controls with normal thyroid function (n = 1088). MEASUREMENTS: Participants gave detailed information on current and previous alcohol intake as well as other factors to be used for analyses. The association between alcohol intake and development of hyperthyroidism was analysed in conditional multivariate Cox regression models. RESULTS: Graves' patients had a lower reported alcohol consumption than controls (median units of alcohol (12 g) per week: 2 vs 4, P < 0·001). In a multivariate regression model, alcohol consumption was associated with a dose-dependent reduction in risk for development of overt Graves' hyperthyroidism. Odds ratios (95% confidence interval) compared with the reference group with a recent (last year) consumption of 1-2 units of alcohol per week were as follows: 0 units/week 1·73 (1·17-2·56), 3-10 units/week 0·56 (0·39-0·79), 11-20 units/week 0·37 (0·21-0·65), ≥21 units/week 0·22 (0·08-0·60). Similar results were found for maximum previous alcohol consumption during a calendar year. No interaction was found with the type of alcohol consumed (wine vs beer), smoking habit, age, gender or region of inhabitancy. CONCLUSIONS: Moderate alcohol consumption is associated with a considerable reduction in the risk of Graves' disease with hyperthyroidism--irrespective of age and gender. Autoimmune thyroid disease seems to be much more dependent on environmental factors than hitherto anticipated.

Genetically driven target tissue overexpression of CD40: a novel mechanism in autoimmune disease.

The CD40 gene, an important immune regulatory gene, is also expressed and functional on nonmyeloid-derived cells, many of which are targets for tissue-specific autoimmune diseases, including ß cells in type 1 diabetes, intestinal epithelial cells in Crohn's disease, and thyroid follicular cells in Graves' disease (GD). Whether target tissue CD40 expression plays a role in autoimmune disease etiology has yet to be determined. In this study, we show that target tissue overexpression of CD40 plays a key role in the etiology of autoimmunity. Using a murine model of GD, we demonstrated that thyroidal CD40 overexpression augmented the production of thyroid-specific Abs, resulting in more severe experimental autoimmune GD (EAGD), whereas deletion of thyroidal CD40 suppressed disease. Using transcriptome and immune-pathway analyses, we showed that in both EAGD mouse thyroids and human primary thyrocytes, CD40 mediates this effect by activating downstream cytokines and chemokines, most notably IL-6. To translate these findings into therapy, we blocked IL-6 during EAGD induction in the setting of thyroidal CD40 overexpression and showed decreased levels of thyroid stimulating hormone receptor-stimulating Abs and frequency of disease. We conclude that target tissue overexpression of CD40 plays a key role in the etiology of organ-specific autoimmune disease.

Thyroid disorders during pregnancy.

Thyroid physiology is altered during pregnancy as a result of an increase in thyroid-binding globulin, the stimulatory effect of hCG on TSH receptors, and increased peripheral thyroid hormone requirements. In addition, hyper and hypothyroid disorders are prevalent among women of reproductive age, and most of them have a significant impact on the gravida, fetus and neonate. Aberrant thyroid function can be readily recognized and treated during pregnancy, avoiding such complications. Here, we will review the thyroid function changes occurring during pregnancy, the different disorders, their maternal and fetal implications, and the ways to screen, prevent and treat these conditions.

[The etiology of Graves' disease--current state of knowledge]. / Etiologia choroby Gravesa--aktualny stan wiedzy.

Graves' disease (GD) is an autoimmune thyroid disease of unknown etiology. Recently, it is assumed that the occurrence of GD co-existence with endogenous factors (genetic and interthyroid) and exogenous (environmental). Autoantibodies against the TSHR are a key element leading to the occurrence of autoimmune thyroid disease. TSHR stimulating antibodies dominate and lead to the development of hyperthyroidism. Among the environmental factors which directly affecting the defect-suppressor T cells can be calculated: infections, smoking, stress, excessive iodine intake, certain medications, therapy with radioiodine. Scientific reports in recent years allow more and better understand the mechanisms leading to the development CD at the molecular level. Linked to this is the hope of creating new treatments and prevention strategies.

Induction of murine neonatal tolerance against Graves' disease using recombinant adenovirus expressing the TSH receptor A-subunit.

Graves' disease is a common organ-specific autoimmune disease. The identity of its autoantigen, the TSH receptor (TSHR), was established and used to induce a typical animal model. A-subunit, the shed portion of TSHR, either initiates or amplifies the autoimmune response of the thyroid gland, thereby causing Graves' disease in humans. In the present study, we investigate the effect of the TSHR A-subunit on the induction of murine neonatal tolerance for the development of Graves' disease. Female BALB/c mice were pretreated with different doses of adenovirus expressing the A-subunit of TSHR (Ad-TSHR289) by either ip or im injection within the first 24 h after their birth. Graves' disease was induced after the animals reached adulthood. Nearly all mice pretreated with the high dose of Ad-TSHR289 failed to develop TSHR antibodies, detected by the TSH-binding inhibition assay, hyperthyroidism, and thyroid follicular hyperplasia. The mice preimmunized im with the lower doses of Ad-TSHR289 developed a relatively low level of TSH-binding inhibition and the low incidence of hyperthyroidism. Accordingly, the percentages of splenic CD4+CD25+/CD4+ and CD25+Foxp3+/CD4+ Treg cells were increased in mice pretreated with the high dose of Ad-TSHR289. Taken together, our data strongly indicate that the immunotolerance against Graves' disease could be induced in neonatal mice using a specific TSHR antigen in a high dose either by ip or im injection, preventing the development of Graves' disease.

B cell-targeted therapy with anti-CD20 monoclonal antibody in a mouse model of Graves' hyperthyroidism.

Graves' disease is a B cell-mediated and T cell-dependent autoimmune disease of the thyroid which is characterized by overproduction of thyroid hormones and thyroid enlargement by agonistic anti-thyrotrophin receptor (TSHR) autoantibody. In addition to antibody secretion, B cells have recently been recognized to function as antigen-presenting/immune-modulatory cells. The present study was designed to evaluate the efficacy of B cell depletion by anti-mouse (m) CD20 monoclonal antibody (mAb) on Graves' hyperthyroidism in a mouse model involving repeated injection of adenovirus expressing TSHR A-subunit (Ad-TSHR289). We observe that a single injection of 250 µg/mouse anti-mCD20 mAb eliminated B cells efficiently from the periphery and spleen and to a lesser extent from the peritoneum for more than 3 weeks. B cell depletion before immunization suppressed an increase in serum immunoglobulin (Ig)G levels, TSHR-specific splenocyte secretion of interferon (IFN)-γ, anti-TSHR antibody production and development of hyperthyroidism. B cell depletion 2 weeks after the first immunization, a time-point at which T cells were primed but antibody production was not observed, was still effective at inhibiting antibody production and disease development without inhibiting splenocyte secretion of IFN-γ. By contrast, B cell depletion in hyperthyroid mice was therapeutically ineffective. Together, these data demonstrate that B cells are critical not only as antibody-producing cells but also as antigen-presenting/immune-modulatory cells in the early phase of the induction of experimental Graves' hyperthyroidism and, although therapeutically less effective, B cell depletion is highly efficient for preventing disease development.

Autoimmune thyroid disease in pregnancy: a review.

The maternal physiological changes that occur in normal pregnancy induce complex endocrine and immune responses. During a normal pregnancy, thyroid gland volume may enlarge, and thyroid hormone production increases. Hence, the interpretation of thyroid function during gestation needs to be adjusted according to pregnancy-specific ranges. The elevated prevalence of gestation-related thyroid disorders (10%-15%) and the important repercussions for both mother and fetus reported in multiple studies throughout the world denote, in our opinion, the necessity for routine thyroid function screening both before and during pregnancy. Once thyroid dysfunction is suspected or confirmed, management of the thyroid disorder necessitates regular monitoring in order to ensure a successful outcome. The aim of treating hyperthyroidism in pregnancy with antithyroid drugs is to maintain serum thyroxine (T(4)) in the upper normal range of the assay used with the lowest possible dose of drug, whereas in hypothyroidism, the goal is to return serum thyroid-stimulating hormone (TSH) to the range between 0.5 and 2.5 mU/L.

Prevention of relapse of Graves' disease by treatment with an intrathyroid injection of dexamethasone.

INTRODUCTION: Antithyroid drugs are widely used in the treatment of Graves' disease (GD), but the relapse rate is very high after therapy withdrawal. We evaluated the reduction effects of intrathyroid injection of dexamethasone (IID) on the relapse rate of hyperthyroidism in patients with newly diagnosed GD. PATIENTS AND METHODS: A total of 191 patients with GD completed the study. After 6 months of treatment with methimazole (MMI), the patients were randomly assigned to receive either MMI (96 patients) alone or MMI combined with IID (MMI+IID; 95 patients) treatment for 3 months, followed by continuing a dose of MMI that would maintain euthyroidism for the next 9 months in all of the patients. After withdrawal of the medical therapy, patients were followed for 24 months, and the relapse rate of hyperthyroidism was evaluated. RESULTS: No statistical difference was observed in the levels of serum FT(4), TSH, or TSH receptor antibodies (TR-Ab), the thyroid volume, or the TR-Ab positive rate between the two groups at month 6. After the next 3 months of treatment with MMI+IID or MMI alone, the levels of TSH increased significantly, and the levels of serum TR-Ab, the TR-Ab positive rate, and thyroid volume decreased significantly in the MMI+IID group compared with the MMI group. Seven patients (7.4%) experienced a relapse of overt hyperthyroidism in the MMI+IID group and 49 patients (51%) in MMI group during the 2-yr follow-up period (P < 0.001). CONCLUSIONS: MMI+IID treatment is helpful to prevent relapse of hyperthyroidism in GD after medical therapy withdrawal.

IFNalpha-induced recurrence of Graves' disease ten years after thyroidectomy in chronic viral hepatitis C. Case report.

In contrast to chronic or subacute thyroiditis, Graves' disease rarely complicates IFN-alpha therapy for chronic viral C hepatitis. We report the case of a 51-year-old man in whom IFN-alpha treatment was followed by recurrence of Graves' disease 10 years after thyroidectomy was performed and the patient was declared cured. Despite severe thyrotoxicosis, combined IFN-alpha and ribavirin therapy was continued and radioiodine treatment was considered for Graves' disease.

Enhancement of experimental Graves' disease by intranasal administration of a T cell epitope of the thyrotropin receptor.

We previously showed that immunization of mice with murine fibroblasts transfected with the thyrotropin receptor (TSHR) and a murine major histocompatibility complex (MHC) class II molecule induces immune thyroid disease with the humoral and histological features of human Graves' disease in about 20% of mice. In this model, based on the proliferative response of T cells from hyperthyroid mice to a panel of overlapping TSHR peptides, we now demonstrate that TSHR 121-140 peptide contains an immunodominant T cell epitope. Supporting this conclusion, spleen cells from mice immunized with TSHR 121-140 peptide showed a strong proliferative response to fibroblasts transfected with the TSHR and a murine I-A(k) molecule, but not either alone. Also, intranasal administration of 100 mug of TSHR 121-140 peptide led to suppressed proliferative response of lymph node cells to the peptide. Interestingly, however, administration of this peptide enhanced, rather than suppressed, the frequency and severity of Graves' disease induced by the immunization of the fibroblasts transfected with the TSHR and a murine I-A(k) molecule. Spleen cells from hyperthyroid mice that were pretreated with intranasal peptide tended to produce lesser amounts of IL-4, IL-10 and IFN-gamma than those from normothyroid control mice. Although precise mechanisms of this enhancement remain to be determined, the results suggest that attempts to treat Graves' disease by intranasal administration of an immunodominant TSHR T cell epitope may aggravate, not prevent, the disease.

Thyroid remnant radioiodine ablation in a case of concurrent thyroid carcinoma, Graves' disease, and thyroid ophthalmopathy.

High-dose I-131 thyroid remnant ablation postthyroidectomy for differentiated thyroid carcinoma is beneficial but the risk of visual complications including loss of vision in patients with coexisting Graves' ophthalmopathy is not well documented. We report the case of a 42-year-old man who presented for radioiodine ablation post total thyroidectomy for metastatic papillary carcinoma, who also had Graves' ophthalmopathy and juvenile onset glaucoma. Concurrent presence of all these conditions in the same patient is rarely encountered and this case demonstrates the challenge faced by the clinicians in balancing the benefits and risks of currently recommended management strategies for these conditions. There is a potential risk of visual complications with I-131 therapy in patients with Graves' disease as it can lead to development of or exacerbation of preexisting ophthalmopathy. The acute exacerbation is usually transient and preventable with prophylactic corticosteroids. However, the use of corticosteroids is associated with various complications including exacerbation of glaucoma as demonstrated in this patient.

[Development of neonatal Graves' disease--prediction, prevention and treatment].

It is well known that neonatal hyperthyroidism or neonatal Graves' disease is caused by trans-placental transfer of TSH receptor antibodies. The antibodies stimulate the thyroid gland in the fetal and neonatal stages, which induces hyperfunction of the thyroid gland and increased thyroid hormone production. In this paper, I would like to focus on four clinically interesting issues related neonatal hyperthyroidism. 1. High risk of mothers whose infants develop neonatal Graves' disease. 2. How to predict for development of neonatal Graves' disease. 3. How to prevent for development of neonatal Graves' disease. 4. How to treat the infants with Graves' disease. I also mention on the neonatal thyrotoxicosis and fetal hyperthyroidism.