TSH Receptor Antibodies: Relevance & Utility

Objective: Antibodies (Abs) to the thyrotropin (TSH) receptor (TSH-R) play an important role in the pathogenesis of autoimmune thyroid disease (AITD). We define the complex terminology that has arisen to describe TSH-R-Abs, review the mechanisms of action of the various types of TSH-R-Abs, and discuss significant advances that have been made in the development of clinically useful TSH-RAb assays.Methods: Literature review and discussion.Results: TSH-R-Abs may mimic or block the action of TSH or be functionally neutral. Stimulating TSH-R-Abs are specific biomarkers for Graves disease (GD) and responsible for many of its clinical manifestations. TSH-R-Abs may also be found in patients with Hashimoto thyroiditis in whom they may contribute to the hypothyroidism of the disease. Measurement of TSH-R-Abs in general, and functional Abs in particular, is recommended for the rapid diagnosis of GD, differential diagnosis and management of patients with AITD, especially during pregnancy, and in AITD patients with extrathyroidal manifestations such as orbitopathy. Measurement of TSH-R-Abs can be done with either immunoassays that detect specific binding of Abs to the TSH-R or cell-based bioassays that also provide information on their functional activity and potency. Application of molecular cloning techniques has led to significant advances in methodology that have enabled the development of clinically useful bioassays. When ordering TSH-R-Ab, clinicians should be aware of the different tests available and how to interpret results based on which assay is performed. The availability of an international standard and continued improvement in bioassays will help promote their routine performance by clinical laboratories and provide the most clinically useful TSH-R-Ab results.Conclusion: Measurement of TSH-R-Abs in general, and functional (especially stimulating) Abs in particular, is recommended for the rapid diagnosis, differential diagnosis, and management of patients with Graves hyperthyroidism, related thyroid eye disease, during pregnancy, as well as in Hashimoto thyroiditis patients with extra-thyroidal manifestations and/or thyroid-binding inhibiting immunoglobulin positivity.Abbreviations: Ab = antibody; AITD = autoimmune thyroid disease; ATD = antithyroid drug; cAMP = cyclic adenosine 3′,5′-monophosphate; ELISA = enzyme-linked immunosorbent assay; GD = Graves disease; GO = Graves orbitopathy; HT = Hashimoto thyroiditis; MAb = monoclonal antibody; TBAb = thyrotropin receptor blocking antibody; TBII = thyroid-binding inhibiting immunoglobulin; TSAb = thyrotropin receptor–stimulating antibody; TSB-Ab or TRBAb = thyrotropin receptor–stimulating blocking antibody; TSH = thyrotropin; TSH-R = thyrotropin receptor     

Gender Influences the Clinical Presentation and Long-Term Outcome of Graves Disease

Objective: The outcome of antithyroid drug (ATD) treatment for Graves disease (GD) is difficult to predict. In this study, we investigated whether male gender, besides other factors usually associated with a poor outcome of ATD treatment, may affect disease presentation and predict the response to medical treatment in subjects with GD.Methods: We studied 294 patients with a first diagnosis of GD. In all patients, ATD treatment was started. Clinical features, thyroid volume, and eye involvement were recorded at baseline. Serum levels of free thyroxine (FT4), free triiodothyronine (FT3), thyroid-stimulating hormone (TSH), and TSH-receptor antibodies (TRAb) were measured at baseline and during the follow-up. Treatment outcome (FT4, FT3, and TSH serum levels and further treatments for GD after ATD withdrawal) was evaluated.Results: When compared to women, men showed a significantly larger thyroid volume and a higher family positivity for autoimmune diseases. During ATD, the mean serum levels of TSH, FT4, FT3, and TRAb did not differ between groups. Within 1 year after ATD discontinuation, relapse of hyperthyroidism was significantly more frequent in men than in women. Within the 5-year follow-up period, the prevalence of men suffering a late relapse was higher compared with that of women. The outcome at the end of the 5-year follow-up period was significantly associated with gender and TRAb levels at disease onset.Conclusion: Male patients with GD have a poorer prognosis when submitted to medical treatment with ATDs. A larger goiter at presentation and a stronger genetic autoimmune background might explain this gender difference in patients with GD.Abbreviations:ATD = antithyroid drugFT3 = free triiodothyronineFT4 = free thyroxineGD = Graves diseaseGO = Graves orbitopathyRAI = radioiodineTRAb = thyroid-stimulating hormone-receptor antibodyTSH = thyroid-stimulating hormone     

Age related changes of soluble Fas, Fas ligand and Bcl-2 in autoimmune thyroid diseases

INTRODUCTION: Apoptosis plays a pivotal role in the regulation of immune mechanisms in the pathogenesis of autoimmune thyroid diseases (AITD). The prevalence of AITD increases with age. Purpose to compare soluble Fas, FasL and Bcl-2 in Graves disease (GD) and Hashimoto thyroiditis (HT) in relation to the age of the studied patients. MATERIAL AND METHODS: 3 groups of subjects: 1/25 patients with GD in euthyreosis on methimazol 2/27 patients with ChH in euthyreosis on levothyroxine. 3/12 healthy volunteers age and sex-matched to group 1-2. The serum levels of Fas, FasL and Bcl-2 were determined by the ELISA kit. RESULTS: We found positive correlations between sFas and age in GD patients (r = 0.35; p < 0.05). In GD patients we found a negative correlation between sFasL and age in all studied patients with AITD (r = -0.34; p < 0.01). We also found a negative correlation between sBcl-2 and age in HT patients (r = -0.42; p < 0.05). CONCLUSIONS: Fas/FasL and Bcl-2 signaling pathways seem to be age-related and may explain, at least in part, milder course of Graves disease in elderly patients and increased prevalence of Hashimoto disease in this group of subjects.     

Management of Thyrotoxicosis: Preconception,Pregnancy, and the Postpartum Period

Objective: To review the diagnosis and management of thyrotoxicosis in women who are preconception, pregnant, and in the postpartum period.Methods: Literature review of English-language papers published between 1980 and 2018.Results: Overt thyrotoxicosis occurs in 0.2% of pregnancies and subclinical thyrotoxicosis in 2.5%. Hyperthyroidism in women of childbearing age most frequently is caused by Graves disease (GD). Gestational thyrotoxicosis, transient human chorionic gonadotropin (hCG)-mediated hyperthyroidism, may develop in the first trimester. In the first year following delivery, postpartum thyroiditis, which frequently includes a thyrotoxic phase, occurs in 5% of women. Hyperthyroidism from nodular autonomy is uncommon in women of childbearing age. It is essential to understand the underlying etiology for thyrotoxicosis in order to recommend appropriate treatment. Gestational thyrotoxicosis requires supportive care, without antithyroid drug therapy. GD may be treated with antithyroid drugs, radioactive iodine, or thyroidectomy. Pregnancy, plans for pregnancy, and lactation have important implications for the choice of GD treatment. When thyrotoxicosis presents following delivery, postpartum thyroiditis must be differentiated from GD.Conclusion: The diagnosis and management of thyrotoxicosis in the peripregnancy period present specific challenges. In making management decisions, it is essential to weigh the risks and benefits of treatments not just for the mother but also for the fetus and for breastfed infants. A team approach to management is critical, with close collaboration among endocrinologists, maternal-fetal medicine specialists, and neonatologists.Abbreviations: GD = Graves disease; hCG = human chorionic gonadotropin; MMI = methimazole; PPT = postpartum thyroiditis; PTU = propylthiouracil; T3 = triiodothyronine; T4 = thyroxine; TBG = thyroxine-binding globulin; TRAb = TSH receptor antibody; TSH = thyroid-stimulating hormone     

The Association Between Body Mass Index and Subclinical Thyroid Dysfunction in Different Sexes of Chinese

Objective: To study subclinical thyroid dysfunction (SCTD)—subclinical hyperthyroidism and subclinical hypothyroidism—in Chinese patients in relation to body mass index (BMI) and to determine whether a difference between sexes exists.Methods: This cross-sectional study recruited 13,503 healthy participants (8,345 male, 5,158 female) who participated in a health examination. Clinical data, including anthropometric measurements and serum parameters, were collected. The association between SCTD and the BMI of each sex was analyzed separately by stratifying the data by SCTD type and regarding BMI as a categorical or as a continuous variable in different models. The odds ratio of SCTD was calculated from binary logistic regression models.Results: The prevalence of both subclinical hyperthyroidism and subclinical hypothyroidism was significantly lower in males compared to females. For subclinical hypothyroidism, we found no significant association with BMI in females. In males, there was a significant negative relationship between BMI and subclinical hypothyroidism. For subclinical hyperthyroidism, we did not find any significant relationship with BMI in either sex after stratifying the data and treating BMI as a categorical or as a continuous variable.Conclusion: For subclinical hyperthyroidism, no significant effect was found in either sex. For subclinical hypothyroidism, high BMI was associated with lower rates of subclinical hypothyroidism in males, and no significant correlation was found in females. The mechanism of this sex-specific association between BMI and SCTD needs more verification.Abbreviations: ALT = alanine aminotransferase; AST = aspartate aminotransferase; BMI = body mass index; BUN = blood urea nitrogen; CI = confidence interval; Cr = creatinine; DBP = diastolic blood pressure; FG = fasting glucose; FT3 = free triiodothyronine; FT4 = free thyroxine; HDL = high-density lipoprotein; LDL = low-density lipoprotein; OR = odds ratio; SBP = systolic blood pressure; SCTD = subclinical thyroid dysfunction; TBIL = total bilirubin; TC = total cholesterol; TG = triglyceride; TSH = thyroid-stimulating hormone; UA = uric acid; WBC = white blood cell; WC = waist circumference     

Baseline TSH Level is Associated with Risk of Anti–PD-1–Induced Thyroid Dysfunction

Objective: To characterize anti–programmed cell death 1 (PD-1)–induced thyroid immune-related adverse events (irAEs) in metastatic melanoma patients treated at our institution and to identify risk factors associated with their development.Methods: We reviewed the files of 154 patients with metastatic melanoma treated with PD-1 inhibitors at a single institution from November 1, 2011, to February 28, 2017. The association of thyroid irAEs within 120 days posttreatment initiation with age, gender, melanoma characteristics, treatment protocol, and baseline thyroid-stimulating hormone (TSH) was examined.Results: Overall, 42.4% developed thyroid dysfunction following treatment, including 20.2% (20/99) subclinical thyroid dysfunction, 13.1% (13/99) overt hypothyroidism, and 9.1% (9/99) overt hyperthyroidism. Of those that developed overt hyperthyroidism, 8 progressed to overt hypothyroidism, consistent with thyroiditis. Age, gender, melanoma characteristics, or treatment protocol did not modify the risk of developing thyroid irAEs. Higher baseline TSH was observed in patients who developed overt hypothyroidism versus hyperthyroidism versus those who remained euthyroid (P = .05). A pretreatment TSH >2.19 mIU/mL was associated with an increased risk of overt thyroid dysfunction (odds ratio, 3.46; 95% confidence interval, 1.2 to 9.8).Conclusion: Thyroid dysfunction following treatment with PD-1 inhibitors is common, and patients with a higher baseline TSH appear to be at increased risk. Such patients may benefit from closer monitoring of their thyroid function following initiation of anti PD-1 agents.Abbreviations: CTLA-4 = cytotoxic T-lymphocyte antigen 4; FT3 = free triiodothyronine; FT4 = free thyroxine; irAE = immune-related adverse event; PD-1 = programmed cell death 1; TFT = thyroid function test; TPO = thyroid peroxidase; TSH = thyroid-stimulating hormone     

Long-Term Outcomes of Radioiodine Therapy for Juvenile Graves Disease with Emphasis on Subsequently Detected Thyroid Nodules: A Single Institution Experience from Japan

Objective: To investigate the long-term outcomes of radioiodine therapy (RIT) for juvenile Graves disease (GD) and the ultrasonographic changes of the thyroid gland.Methods: All of 117 juvenile patients (25 males and 92 females, aged 10 to 18 &lsqb;median 16] years) who had undergone RIT for GD at our clinic between 1999 and 2018 were retrospectively reviewed. Each RIT session was delivered on an outpatient basis. The maximum ¹³¹I dose per treatment was 13.0 mCi, and the total ¹³¹I dose per patient was 3.6 to 29.8 mCi (median, 13.0 mCi). ¹³¹I administration was performed once in 89 patients, twice in 26, and three times in 2 patients. Ultrasonography of the thyroid gland was regularly performed after RIT. The duration of follow-up after the initial RIT ranged from 4 to 226 (median 95) months.Results: At the latest follow-up more than 12 months after RIT (n = 111), the patients' thyroid functions were overt hypothyroidism (91%), subclinical hypothyroidism (2%), normal (5%), or subclinical hyperthyroidism (2%). New thyroid nodules were detected in 9 patients, 4 to 17 years after initial RIT. Patients with newly detected thyroid nodules underwent RIT with lower doses of ¹³¹I and had larger residual thyroid volumes than those without nodules. None of the patients were diagnosed with thyroid cancer or other malignancies during the follow-up period.Conclusion: Over a median follow-up period of 95 months (range, 4 to 226 months), RIT was found to be effective and safe in juvenile GD. However, cumulative evidence from further studies is required to confirm the long-term safety of RIT for juvenile GD.Abbreviations: ATD = antithyroid drug; GD = Graves disease; KI = potassium iodide; LT4 = levothyroxine; MMI = methimazole; PTU = propylthiouracil; RAIU = radio-active iodine uptake; RIT = radioiodine therapy; ^99mTc = technetium-99m; TSH = thyrotropin     

Alterations and Mechanism of Gut Microbiota in Graves’ Disease and Hashimoto’s Thyroiditis

To explore the role of gut microbiota in Graves’ disease (GD) and Hashimoto’s thyroiditis (HT). Seventy fecal samples were collected, including 27 patients with GD, 27 with HT, and 16 samples from healthy volunteers. Chemiluminescence was used to detect thyroid function and autoantibodies (FT3, FT4, TSH, TRAb, TGAb, and TPOAb); thyroid ultrasound and 16S sequencing were used to analyze the bacteria in fecal samples; KEGG (Kyoto Encyclopedia of Genes and Genomes) and COG (Clusters of Orthologous Groups) were used to analyze the functional prediction and pathogenesis. The overall structure of gut microbiota in the GD and HT groups was significantly different from the healthy control group. Proteobacteria and Actinobacteria contents were the highest in the HT group. Compared to the control group, the GD and HT groups had a higher abundance of Erysipelotrichia, Cyanobacteria, and Ruminococcus_2 and lower levels of Bacillaceae and Megamonas. Further analysis of KEGG found that the “ABC transporter” metabolic pathway was highly correlated with the occurrence of GD and HT. COG analysis showed that the GD and HT groups were enriched in carbohydrate transport and metabolism compared to the healthy control group but not in amino acid transport and metabolism. Our data suggested that Bacillus, Blautia, and Ornithinimicrobium could be used as potential markers to distinguish GD and HT from the healthy population and that “ABC transporter” metabolic pathway may be involved in the pathogenesis of GD and HT.     

Hashimoto Thyroiditis not Associated with Vitamin D Deficiency

Objective: Vitamin D deficiency is associated with several autoimmune diseases. This study assessed whether vitamin D deficiency is associated with Hashimoto thyroiditis (HT).Methods: Two groups of patients were selected for which serum 25-hydroxyvitamin D (25(OH)D) levels had been measured: (1) a study group of patients diagnosed with HT as indicated by thyroid antibodies, and (2) a healthy control group. Each group was separated by sex and then controlled for age and body mass index (BMI). Groups' mean 25(OH)D levels were compared by analysis of variance (ANOVA), and percent frequencies of vitamin D sufficiency, insufficiency, and deficiency were compared with a Z-test. The correlations between 25(OH)D levels and thyroid antibodies and thyroid-stimulating hormone (TSH) levels were also tested.Results: The mean 25(OH)D levels for the HT and control groups were significantly different in females (30.75 vs. 27.56 ng/mL, respectively) but not in males (14.24 vs. 13.26 ng/mL). HT females had a higher rate of vitamin D sufficiency (51.7% vs. 31.1%) and a lower rate of insufficiency (48.3% vs. 68.9%) relative to control females. No such differences were found in the male groups. None of the females were vitamin D deficient, but almost all males were. A significant (P = .016) positive correlation (r_s = 0.436) between 25(OH)D and TPOAb was observed in males.Conclusion: HT is not associated with higher rates of vitamin D deficiency relative to a control group.Abbreviations:BMI = body mass indexHT = Hashimoto thyroiditis25(OH)D = 25-hydroxyvitamin DTgAb = thyroglobulin antibodyTSH = thyroid-stimulating hormoneTPOAb = thyroid-peroxidase antibodyVDR = Vitamin D receptor     

Killer Cell Immunoglobulin-Like Receptor Genes and their HLA-C Ligands in Hashimoto Thyroiditis in a Chinese Population

Objective: Natural killer (NK) cells serve as primary immune surveillance and are partially regulated by combinations of killer immunoglobulin-like receptors (KIR) and their human leukocyte antigen-C (HLA-C) ligands. Alterations in NK cell activity have been associated with Hashimoto thyroiditis (HT). The aim of this study was to determine whether certain KIR/HLA-C genotype combinations play a role in HT pathogenesis.Methods: The present study enrolled 107 unrelated HT patients and 108 random healthy individuals in a case-control study. Blood was collected for DNA extraction; typing of KIR genes and HLA-C alleles was performed by polymerase chain reaction with sequence specific primers (PCR-SSP), followed by electrophoresis on agarose gels.Results: Among a panel of KIR2D/HLA-C genotype combinations, the frequency of KIR2DS2/HLA-C1 was significantly increased in HT patients compared to controls (33.64% vs. 12.96%, P<.001). To further analyze the precise genotype, we investigated inhibitory or activating KIR/HLA-C gene pairs when their corresponding activating or inhibitory KIR genes were absent in the 2 groups. Only the frequency of KIR2DS2(-)2DL2/3(+)HLA-C1(+) was significantly decreased in HT patients compared to controls (48.60% vs. 70.37%, P = .001).Conclusion: Our data suggest that KIR2DS2/HLA-C1 may correlate with HT pathogenesis. On the contrary, the predominance of KIR2DL2/3/HLA-C1 in the absence of KIR2DS2 suggests a potential inhibitory role in HT pathogenesis. In conclusion, our findings may further elucidate the mechanisms underlying the pathogenesis of HT and other autoimmune diseases.Abbreviations:HLA-C = human leukocyte antigen-CHT = Hashimoto thyroiditisKIR = killer immunoglobulin-like receptorNK = natural killerPCR = polymerase chain reaction     

A Comparative Study of the Oxidative Profile in Graves’ Disease, Hashimoto’s Thyroiditis, and Papillary Thyroid Cancer

The aim of this study was to evaluate and compare the oxidative profiles of three thyroid disorders: Graves’ disease (GD), Hashimoto thyroiditis (HT), and papillary thyroid cancer (PTC). Malondialdehyde levels (MDA), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) activities were examined in the plasma of 52 patients (29 untreated HT, 16 untreated GD, and 7 PTC who underwent surgical therapy). Results were compared with those of 30 healthy controls and among the three groups of patients. The GD, HT, and PTC patients exhibited increased plasma MDA levels and SOD activities compared with the controls (p?<?0.05, p?<?0.05, and p?<?0.001, respectively). CAT activities significantly increased only for the PTC and HT patients (p?<?0.001 and p?<?0.05, respectively), whereas GPx activities significantly decreased only in the GD and PTC (p?<?0.05 and p?<?0.01, respectively). The comparison among the three groups of patients has shown increased MDA level and SOD activity for the PTC patients as compared to the GD patients (p?<?0.01 and p?<?0.001, respectively). Compared with HT, PTC patients exhibited significant higher MDA level, SOD, and CAT activities and a significant lower GPx activity (p?<?0.01, p?<?0.001, p?<?0.05, and p?<?0.05, respectively). No significant discrepancies were noted between the GD and HT patients. Our results have clearly shown an oxidative profile that is highly disturbed for the PTC patients as compared to those of autoimmune disorders. Future studies are needed to determine whether or not the oxidative stress has a prognostic value in this pathology.     

No Longterm Severe Thyroid Dysfunction Seen In Patients With Preexisting Reduced Serum Tt3 Concentrations After A Single Large Dose Of Iodinated Contrast

Objective: After an intravenous bolus injection of 100 mL of iodinated contrast agent (370 mgI/mL), the amount of iodine atoms entering the blood is tens of thousands of times the daily dose of iodine recommended by the World Health Organization. However, the effect of iodinated contrast in patients with nonthyroidal illness, manifested as reduced serum total triiodothyronine (TT3) concentrations, is unclear. We studied the effect of iodinated contrast on thyroid function and auto-antibodies in patients with reduced TT3 after diagnosis and treatment of coronary heart disease.Methods: This was a prospective cohort study. One hundred and fifty-four stable angina pectoris patients with reduced TT3 and normal thyroid-stimulating hormone (TSH), free thyroxine (FT4), and reverse triiodothyronine (rT3) were enrolled from January, 2017, to June, 2018. All subjects had no history of thyroid dysfunction and had no recent infections, tumors, trauma, or other critical illnesses. Fourty-one patients underwent coronary angiography and 113 patients underwent coronary intervention.Results: There were 6 patients (3.9%) with hypothyroidism and 30 patients (19.5%) developed subclinical hypothyroidism (SCHypo) on the first day after surgery. There were 6 patients (3.9%) with hypothyroidism, 6 patients (3.9%) with SCHypo, and 18 patients (11.7%) with subclinical hyperthyroidism (SCHyper) at the first month postsurgery. There were 23 patients (14.9%) with SCHyper and 6 patients (3.9%) with SCHypo at the sixth month after surgery. No patient with longterm severe thyroid dysfunction occurred during follow-up. The levels of free triiodothyronine, FT4, TT3, total thyroxine, and TSH showed statistically significant changes at 1 day, and 1, 3, and 6 months postoperative (P<.005). The level of rT3 showed no statistically significant change at 1, 3, and 6 months postoperative (P>.05). The levels of thyroglobulin antibody and thyroid peroxidase antibody decreased at 6 months postoperative (P<.001).Conclusion: The risk of subclinical thyroid dysfunction and transient hypothyroidism occurred with a single large dose of iodinated contrast in the diagnosis and treatment of coronary heart disease, but no longterm severe thyroid dysfunction occurred. Patients with preoperative thyroid antibody elevation were more likely to have subclinical thyroid dysfunction after surgery.Abbreviations: FT3 = free triiodothyronine; FT4 = free thyroxine; PCI = percutaneous coronary intervention; rT3 = reverse triiodothyronine; SCHyper = subclinical hyperthyroidism; SCHypo = subclinical hypothyroidism; TGAB = thyroglobulin antibody; TPOAB = thyroid peroxidase antibody; TT3 = total triiodothyronine; TT4 = total thyroxine; TSH = thyroid-stimulating hormone; WHO = World Health Organization     

Graves Hyperthyroidism and Pregnancy: A Clinical Update

ObjectiveTo provide a clinical update on Graves’ hyperthyroidism and pregnancy with a focus on treatment with antithyroid drugs.MethodsWe searched the English-language literature for studies published between 1929 and 2009 related to management of hyperthyroidism in pregnancy. In this review, we discuss differential diagnosis of hyperthyroidism, management, importance of early diagnosis, and importance of achieving proper control to avoid maternal and fetal complications.ResultsDiagnosing hyperthyroidism during pregnancy can be challenging because many of the signs and symptoms are similar to normal physiologic changes that occur in pregnancy. Patients with Graves disease require prompt treatment with antithyroid drugs and should undergo frequent monitoring for signs of fetal and maternal hyperthyroidism and hypothyroidism. Rates of maternal and perinatal complications are directly related to control of hyperthyroidism in the mother. Thyroid receptor antibodies should be assessed in all women with hyperthyroidism to help predict and reduce the risk of fetal or neonatal hyperthyroidism or hypothyroidism. The maternal thyroxine level should be kept in the upper third of the reference range or just above normal, using the lowest possible antithyroid drug dosage. Hyperthyroidism may recurin the postpartum period as Graves disease or postpartum thyroiditis; thus, it is prudent to evaluate thyroid function 6 weeks after delivery. Preconception counseling, a multidisciplinary approach to care, and patient education regarding potential maternal and fetal complications that can occur with different types of treatment are important.ConclusionPreconception counseling and a multifaceted approach to care by the endocrinologist and the obstetric team are imperative for a successful pregnancy in women with Graves hyperthyroidism. (Endocr Pract. 2010;16:118-129)     

A novel compound heterozygous variant Of SLC12A3 Gene in A Pedigree with Gitelman Syndrome Co-Existent with Thyroid Dysfunction

Objective: Gitelman syndrome (GS) is an autosomal recessive disorder characterized by salt wasting and hypokalemia resulting from mutations in the SLC12A3 (solute carrier family 12 member 3) gene, which encodes the thiazide-sensitive sodium-chloride cotransporter. To date, more than 488 mutations of the SLC12A3 gene have been discovered in patients with GS. In this study, we reported a GS pedigree complicated by thyroid diseases or thyroid dysfunction.Methods: Sanger sequencing and next-generation sequencing analysis were performed to determine the SLC12A3 gene mutations in a GS pedigree including the 16-year old male patient with GS and his family members within 3 generations. Chemiluminescence immunoassays were used to detect thyroid hormone and antibody concentrations.Results: Genetic analysis of the SLC12A3 gene identified 2 mutations in the 16-year old male patient with GS concomitant with Graves disease (GD) and his younger sister accompanied by abnormal thyroid function. Additionally, one mutation site (c.1456G>A) in SLC12A3 gene was found in his father, paternal uncle and elder female cousin, who were complicated by subclinical hypothyroidism or autoantibody against thyroid. The other mutation site (c.2102_2107 delACAAGA) in SLC12A3 gene, a novel mutated variant of SLC12A3 gene, was carried by his mother and maternal grandfather.Conclusion: Two mutation sites were documented in the pedigree with GS, and one has not been reported before. Moreover, we found a mutation at nucleotide c.1456 G>A in the SLC12A3 gene that may affect thyroid function. However, further studies are needed to explore the underlying molecular mechanisms.Abbreviations: FT3 = free triiodothyronine; FT4 = free tetraiodothyronine; GD = Graves disease; GS = Gitelman syndrome; SLC12A3 = solute carrier family 12 member 3; TGAb = thyroglobulin antibody; TPOAb = thyroid peroxidase antibody; TSH = thyroid-stimulating hormone; TT3 = total triiodothyronine; TT4 = total tetraiodothyronine     

Platelet-Lymphocyte Ratio as a Novel Surrogate Marker to Differentiate Thyrotoxic Patients with Graves Disease from Subacute Thyroiditis: a Cross-Sectional Study from South India

Objective: Graves disease (GD) and the toxic phase of subacute thyroiditis (SAT) have similar clinical and biochemical presentations, and differentiating them requires sophisticated investigations. Since thyroid hormones have been noted to affect all hematologic cell lines, we have used the platelet lymphocyte ratio (PLR)—an index usually utilized in inflammatory or malignant disorders—to compare patients with and without thyrotoxicosis and to analyze its use in distinguishing between patients with GD and SAT prior to therapy.Methods: This was a cross-sectional study conducted in the Department of Endocrinology, Christian Medical College, Vellore, India. During the study period, 800 patients with features of thyrotoxicosis visited the outpatient clinic. Those who had thyroid radioiodine (¹³¹I) uptake (RAIU) study and complete blood count (CBC) at diagnosis were included (N = 500). Based on the RAIU values, these were divided as GD (n = 354) and SAT (n = 146). Baseline characteristics, thyroid function tests, and components of the CBC and PLR were obtained. The data were compared with a group of 250 matched euthyroid controls. Analyses were performed using SPSS version 21.0 software.Results: PLR showed significant reductions in both GD and SAT patients when compared to euthyroid controls (P = .01), with greater reductions seen in GD than SAT (74.5 ± 19 vs. 84.4 ± 26; P = .01). Using receiver operating characteristic analysis of PLR, an optimal PLR cut-off of 70.4 was found to differentiate GD from SAT with a sensitivity of 86% and specificity of 74%.Conclusion: PLR can be used as a novel surrogate marker to differentiate between patients with GD and SAT prior to therapy, especially in resource-limited settings.     

Positive Thyrotropin Receptor Antibodies in Patients with Transient Thyrotoxicosis

Objective: Thyrotropin (TSH) receptor antibody (TRAb) testing is considered accurate for the diagnosis of Graves disease (GD) and has been identified rarely in thyrotoxic patients without GD. We describe 4 patients with transient thyrotoxicosis and positive TRAb to highlight this clinical possibility.Methods: Patient demographics, symptoms, laboratory findings, and time to resolution of thyrotoxicosis are summarized. TRAb testing was performed by either a third-generation thyrotropin-binding inhibitory immunoglobulin (TBII) competitive-binding assay or a thyroid-stimulating immunoglobulin (TSI) bioassay from either Mayo Clinic Laboratory or Quest Diagnostics.Results: Four patients with transient thyrotoxicosis and positive TRAb testing were identified. Of these, three were female, and the median age was 44 years (range, 25 to 49 years). Median symptom duration at evaluation was 6.5 weeks (range, 3 to 12 weeks). No patient had any clinical manifestations unique to GD or exposure to biotin, thyroid hormone, supplements, iodine, or relevant medications. The TSH was <0.1 mIU/L in all patients. Three patients had a positive TSI, which was elevated less than twice the upper limit of the reference range in all cases, and 1 patient had a strongly positive TBII. None of the patients were treated with thionamides or radioactive iodine. Spontaneous resolution occurred in all patients at a median of 5.5 weeks (range, 2 to 14.4 weeks).Conclusion: These cases demonstrate that TSI or TBII may be present in thyrotoxic patients with transient thyrotoxicosis. For clinically stable patients presenting without pathognomonic evidence of GD, mildly elevated TRAb results may require cautious interpretation, and alterative diagnostic testing or close monitoring should be considered.Abbreviations: cAMP = cyclic adenosine monophosphate; FT4 = free thyroxine; GD = Graves disease; TBII = thyrotropin-binding inhibitory immunoglobulin (also known as TBI); TRAb = thyrotropin receptor antibody; TSH = thyrotropin; TSHR = thyrotropin receptor; TSI = thyroid-stimulating immunoglobulin; TT3 = total triiodothyronine; TT4 = total thyroxine     

Prognosis of Differentiated Thyroid Carcinoma in Patients with Graves Disease: A Systematic Review and Meta-Analysis

Objective: It is still controversial whether differentiated thyroid carcinoma (DTC) in patients with Graves disease (GD) can be more aggressive than non-Graves DTC. We conducted a systematic review and meta-analysis to examine the association between GD and prognosis in patients with DTC.Methods: We comprehensively searched the databases of MEDLINE and EMBASE from inception to March 2019. We included published studies that compared the risk of mortality and prognosis between DTC patients with GD and those with non-GD. Data from each study were combined using the random-effects model.Results: Twenty-five studies from February 1988 to May 2018 were included (987 DTC patients with GD and 2,064 non-Graves DTC patients). The DTC patients with GD had a significantly higher risk of associated multifocality/multicentricity (odds ratio, 1.45; 95% confidence interval, 1.04 to 2.02; I², 6.5%; P =.381) and distant metastasis at the time of cancer diagnosis (odds ratio, 2.19; 95% confidence interval, 1.08 to 4.47; I², 0.0%; P =.497), but this was not associated with DTC-related mortality and recurrence/persistence during follow-up.Conclusion: Our meta-analysis demonstrates a statistically significant increased risk of multifocality/multicentricity and distant metastasis at the time of cancer diagnosis in DTC patients with GD than those without GD.Abbreviations: CI = confidence interval; DTC = differentiated thyroid carcinoma; GD = Graves disease; LN = lymph node; OR = odds ratio; PTC = papillary thyroid carcinoma; TC = thyroid carcinoma; TSAb = thyroid-stimulating antibody; TSH = thyroid-stimulating hormone     

HLA DQ2 Haplotype,Early Onset of Graves Disease,and Positive Family History of Autoimmune Disorders are Risk Factors for Developing Celiac Disease in Patients with Graves Disease

Objective: The diagnosis of celiac disease (CD) in patients with different autoimmune diseases including Graves disease (GD) remains a challenge. The aims of our study were to: (1) assess the prevalence of CD in Polish patients with GD and (2) evaluate the prevalence of CD in the subgroups of patients with GD divided on the basis of clinical and human leukocyte antigen (HLA) typing criteria.Methods: The prospective study was conducted at an academic referral center. The study groups consisted of consecutive, euthyroid patients with GD (n = 232) and healthy volunteers without autoimmune thyroid diseases (n = 122). The diagnosis of CD was based on elevated immunoglobulin A autoantibodies to the enzyme tissue transglutaminase (IgA-TTG) and small intestine biopsy findings.Results: CD was diagnosed in 8 patients with GD (3.4%) and 1 healthy volunteer (0.8%). The development of CD in patients with GD was strongly associated with HLA-DQ2 haplotype (as predicted from linkage disequilibria, 14.6% vs. 1.5%, P = .009; odds ratio [OR] = 11.3; 95% confidence interval [CI] 1.3–252.7): 6 patients with CD carried HLA-DRB1*03, 1 carried an HLA-DRB1*04 allele, and 1 had an HLA-DRB1*07/*11 genotype. Multivariate analysis showed independent associations between CD and early GD onset (P = .014, OR = 9.6), autoimmunity in family (P = .029, OR = 6.3) and gastroenterologic symptoms (P = .031, OR = 8.1).Conclusions: The results of our study suggest that serologic screening for CD may be considered in GD patients (1) with the HLA alleles typical for CD, (2) with an early onset of GD, or (3) a family history of autoimmunity. Moreover, the diagnosis of CD should be explored in euthyroid GD patients with nonspecific gastrointestinal symptoms.Abbreviations: AITD = autoimmune thyroid disease APS = autoimmune polyglandular syndromes CD = celiac disease CI = confidence interval GD = Graves disease GFD = gluten-free diet HLA = human leukocyte antigen IgA-TTG = immunoglobulin A autoantibodies to the enzyme tissue transglutaminase OR = odds ratio T1D = type 1 diabetes mellitus TBII = TSH-binding inhibitory immunoglobulins TSH = thyroid-stimulating hormone     

A 2017 Survey of the Clinical Practice Patterns in the Management of Relapsing Graves Disease

Objective: Previous surveys from different world regions have demonstrated variations in the clinical management of Graves disease (GD). We aimed to investigate the clinical approach to GD relapse among endocrinologists.Methods: Electronic questionnaires were e-mailed to all members of the Israeli Endocrine Society. Questionnaires included demographic data and different scenarios regarding treatment and follow-up of patients with GD relapse.Results: The response rate was 49.4% (98/198). For a young male with GD relapse, 68% would restart antithyroid drug (ATD) (98% methimazole), while 32% would refer to radioactive iodine (RAI) treatment. Endocrinologists who treat >10 thyroid patients a week tended to choose ATDs over RAI (P = .04). In the case of GD relapse with ophthalmopathy, 50% would continue ATDs, whereas 22.4% would recommend RAI treatment and 27.6% surgery. Most endocrinologists (56%) would continue ATDs for 12 to 24 months. Seventy-five percent would monitor complete blood count and liver function (39% for the first month and 36% for 6 months), and 44% would recommend a routine neck ultrasound. In a case of thyrotoxicosis due to a 3-cm hot nodule, most endocrinologists (70%) would refer to RAI ablation, 46.4% without and 23.7% with a previous fine-needle aspiration. No significant differences were found regarding gender, year of board certification, or work environment.Conclusion: Our survey demonstrates diverging patterns in the diagnosis and management of GD relapse that correlate well with previous surveys from other countries on GD-naïve patients and a less than optimal adherence to recently published clinical guidelines.Abbreviations: ATA = American Thyroid Association; ATD = antithyroid drug; CBC = complete blood count; GD = Graves disease; GO = Graves ophthalmopathy; LFT = liver function test; MMI = methimazole; PTU = propylthiouracil; RAI = radioactive iodine; TSI = thyroid-stimulating immunoglobulin