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Graves' orbitopathy (GO) is an orbital autoimmune disorder and the main extrathyroidal manifestation of Graves' disease, the most common cause of hyperthyroidism. GO affects about 30% of Graves' patients, although fewer than 10% have severe forms requiring immunosuppressive treatments. Management of GO requires a multidisciplinary approach. Medical therapies for active moderate-to-severe forms of GO (traditionally, high-dose glucocorticoids) often provide unsatisfactory results, and subsequently surgeries are often needed to cure residual manifestations. The aim of this review is to provide an updated overview of current concepts regarding the epidemiology, pathogenesis, assessment, and treatment of GO, and to present emerging targeted therapies and therapeutic perspectives. Original articles, clinical trials, systematic reviews, and meta-analyses from 1980 to 2021 were searched using the following terms: Graves' disease, Graves' orbitopathy, thyroid eye disease, glucocorticoids, orbital radiotherapy, rituximab, cyclosporine, azathioprine, teprotumumab, TSH-receptor antibody, smoking, hyperthyroidism, hypothyroidism, thyroidectomy, radioactive iodine, and antithyroid drugs. Recent studies suggest a secular trend toward a milder phenotype of GO. Standardized assessment at a thyroid eye clinic allows for a better general management plan. Treatment of active moderate-to-severe forms of GO still relies in most cases on high-dose systemic-mainly intravenous-glucocorticoids as monotherapy or in combination with other therapies-such as mycophenolate, cyclosporine, azathioprine, or orbital radiotherapy-but novel biological agents-including teprotumumab, rituximab, and tocilizumab-have achieved encouraging results.

To investigate the long-term outcomes and prognosis of thyrotoxicosis in a large number of patients in a single UK county (Leicestershire).Retrospective cohort analysis of 56,741 thyroid function test (TFT) results, treatment modalities and outcomes in a well-established virtual thyrotoxicosis clinic database.One thousand four hundred and eighty-nine patients were included with a median length of follow-up of 10.9 years. The aetiology of thyrotoxicosis was autoimmune (85.9%), nodular (9.1%) and mixed (5.0%). Treatment modalities included antithyroid drugs (ATDs), radioiodine (RAI; 555 MBq fixed dose) and thyroidectomy.We analysed both individual TFTs and groups of sequential TFTs on or after the same thyroid treatment(s), which we describe as 'phase of thyroid care' (POTC). Patients studied entered the virtual clinic between 1 January 1995 and 1 January 2010; we exported data on every TFT sample up to April 2020.ATD had been used in 99.2% (median 2, maximum seven courses) with long-term ATD (gt;2 years) in 48%. RAI and thyroidectomy were used more commonly with nodular and mixed aetiology. Overall, T4 was more often controlled than thyroid-stimulating hormone (TSH), and at the latest follow-up, T4 was normal ingt;96%, TSH ingt;79% and both ingt;76% of different aetiologies. The mean percentage control of T4 was 85% and TSH 50%; in long-term ATD courses, this improved to 89% and 62%, respectively. In the latest POTC, control of T4 and TSH was best in cases off treatment (95%/87%) and on T4 without ablative therapy (94%/72%), but was broadly similar in patients on long-term ATD (90%/68%), after RAI (92%/60%) or after thyroidectomy (91%/58%). After the first course of ATD, remission or hypothyroidism was seen in 47.3% autoimmune, 20.9% nodular and 32.5% mixed, with 90% relapses seen within 4 years. Relapse was more common in patients with ophthalmopathy, but there was no difference between the sexes.Thyrotoxicosis can be well controlled with minimal specialist clinic attendance using a software-supported virtual shared-care scheme. Long-term ATD appears to be a valid patient choice achieving TFT control comparable to that seen after RAI or surgery. In patients with autoimmune disease, relapse is more common in patients with ophthalmopathy, and hypothyroidism is common after RAI. In nodular disease, we found that spontaneous remission may occur.

To evaluate the prevalence and clinical significance of nonuniform technetium (Patients with GD, referred between July 2005 and March 2018, had TcOf the 276 GD patients (mean age, 49.8 years; 84% female), 25 (9.0%) had nonuniform TcNonuniform radio-isotope uptake is seen in 1 in 11 patients with GD which could be misdiagnosed as toxic multinodular goitre if TRAb levels are not measured. Treatment of GD patients with nonuniform radio-isotope uptake with ATD therapy as first-line appears to be equally effective as compared with those with uniform uptake. TRAb testing should be the main diagnostic test for patients with suspected GD with radio-labelled uptake scans being reserved for those who are TRAb negative.

Objective Insulin autoimmune syndrome (IAS) is the third most common cause of spontaneous hypoglycaemia in Japan but very rare in the rest of the world. We aimed to identify factors, which are associated with the occurrence of IAS and which may differ between East Asian and non-East Asian patients. Design A PubMed search using the search terms 'insulin autoimmune syndrome' and 'Hirata disease' revealed a total of 287 reports of IAS cases, including one previously unpublished own case. Results Mean age (±standard deviation) was 52 ± 19 years in East Asian and 54 ± 21 years in non-East Asian patients (p > .05). In both groups, there were more females. Mean body mass index was lower in East Asian than in non-East Asian patients (23.0 ± 4.3 vs. 27.1 ± 5.6 kg/m2 , p .05), except for insulin that was higher in East Asian compared to non-East Asian metabolically healthy patients (p .05). Conclusions Factors associated with IAS markedly differ between East Asian and non-East Asian patients, with autoimmune disorders, particularly Graves' disease, antithyroid medications, and HLA-DRB1*0406 more prevalent in East Asian patients and cardiovascular and plasma cell diseases, ACE inhibitors and HLA-DRB1*0403 more prevalent in non-East Asian patients.

Background Graves' disease (GD) is a clinical autoimmune thyroid disease. During the treatment of GD, antithyroid drug‐induced agranulocytosis (TIA) is a common and even life‐threatening adverse drug reaction. Previous studies suggested that susceptibility to TIA is strongly associated with HLA‐B*27:05, HLA‐B*38:02, and HLA‐DRB1*08:03 genetic variation and six single nucleotide polymorphisms (SNPs) in MICA genes. Aims The purpose of this study is to further study the associations between TIA, HLA‐B and MICA. Materials & Methods We genotyped MICA‐STR and MICA‐129 variants in 41 TIA and 308 control patients with GD and investigated the linkage effect among SNPs and short tandem repeat (STR) of MICA and HLA‐B alleles. Results The results showed that MICA*A5.1 was significantly associated with TIA (p = .007, odd ratio = 1.958, 95% confidence interval, 1.192–3.214). In addition, high linkage among MICA‐129 and six SNPs MICA and HLA‐B was detected, and two haplotypes (AAAACAAAAACGGCCTA and AACAAAAAAAACATTAA (p = 5.14E−07 and p = 3.42E−08, respectively)) were significantly associated with TIA. Furthermore, when we analyzed only MICA‐129 and HLA‐B separately, the haplotypes (AAAACAAAAAA with p = 2.49E−07 and AACAAAAAAAA with p = 2.14E−09) were identified with more significant effects. MICA‐129 was completely linked to six SNPs with haplotypes ACATTACA (p = 2.05E−05) significantly associated with TIA. Conclusion These data indicated that there was a significant linkage effect between MICA‐129 and other alleles, suggesting that they exert interactive effects as risk factors for the development of TIA., Our manuscript indicated that there was a significant linkage effect between MIA*A5.1, MICA‐129, and other loci, suggesting that they exert interactive effects as risk factors for the development of GD‐TIA.

OBJECTIVE A suboptimal quality of life (QoL) has been reported in patients with Graves' disease treated in adult life, but long-term QoL in those treated in childhood and adolescence is unclear. We wanted to understand how Graves' disease and its management impact on the physical, psychological and social well-being of young people and their longer-term QoL. DESIGN, PATIENTS AND MEASUREMENTS Two questionnaires were used to assess QoL and patient experience of Graves' disease; PedsQL™ Generic Core Scales and a Graves' disease questionnaire devised for this project. The anonymized questionnaires were sent to young people (

Objective Thyroid disorders including hyperthyroidism are common during pregnancy. Untreated hyperthyroidism can result in adverse outcomes for pregnancy. Methods Iodine, propylthiouracil (PTU), carbimazole (CMZ), and methimazole (MMI) are common medications for hyperthyroidism treatment. The literature regarding antithyroid medication use in pregnancy and breastfeeding is reviewed. Results Animal studies for PTU have suggested congenital anomalies while animal studies for MMI have only indicated adverse outcomes at higher doses than used in humans. Epidemiological studies have noted an increased risk of congenital anomalies for PTU less often than CMZ or MMI but the epidemiological evidence remains mixed. A pattern of anomalies has been described for CMZ and MMI, from both case and epidemiological studies, including choanal atresia, aplasia cutis congenita, and other facial, heart, gastrointestinal, and skin anomalies. Closer examination of cases indicates that a few cases of the anomalies have occurred without exposure to CMZ or MMI and outside of the proposed critical period. PTU has a small risk of hepatotoxicity which rarely results in liver transplantation and death. Some authors have suggested that PTU be prescribed in early pregnancy and switched to MMI in late pregnancy. Untreated hyperthyroidism, from either a lack of medications or switching medications during the first trimester, may also increase the chance of congenital anomalies. Multiple case studies and larger epidemiological studies have failed to provide clear, consistent outcomes for the use of PTU, CMZ, and MMI in pregnancy. MMI and PTU both enter the breastmilk in small amounts. Conclusion Additional research is needed to assist in the medical management and exposure counseling of pregnant and breastfeeding women with hyperthyroidism.

Graves' disease is uncommon in children. The remission rate after antithyroid drugs (ATD) therapy is lower than in adults. We evaluated the clinical course of ATD therapy in children with Graves' disease in southern Taiwan to determine whether their biochemical markers could be used to predict remission in these patients. We retrospectively reviewed the clinical data of 53 children diagnosed with Graves' disease between 2009 and 2019. Clinical and biochemical parameters were analyzed for predictors of remission. About three‐fourths of the patients were female. Their median age at diagnosis was 13 years. No sex differences were found in most clinical characteristics. There was no correlation between thyroid‐stimulating hormone receptor antibody (TRAb) levels at diagnosis and thyroid function or adverse reactions to ATD. Relapse occurred in 62% of patients after discontinuation of first‐course ATD therapy. Three variables—good initial response to ATD, a decrease in TRAb levels during the first year after diagnosis, and a decrease in TRAb levels during the second year after diagnosis—were significant predictors of remission for more than 18 months. In conclusion, children with Graves' disease who had early ATD‐controlled Graves' disease and decreased TRAb levels during the first 2 years are likely to enter remission for more than 18 months.

Background The remission rate in children with Graves' disease (GD) after 2-6 years of antithyroid drug (ATD) treatment is 40-50%. It has been reported that it is difficult to predict the GD prognosis based on the TSH receptor antibody (TRAb) level at the cessation of ATD treatment. We studied whether the persistence of negative TRAb at ATD treatment cessation increased the remission rate in pediatric patients with GD. Methods We included 22 patients diagnosed with GD who discontinued ATD treatment after confirmation of negative TRAb on two or more consecutive tests. Remission was defined as the maintenance of normal thyroid function, including serum TSH level, with negative TRAb more than 2 years after ATD discontinuation. Results Of the 22 patients, 12 achieved remission (remission rate 54.5%), with no significant between-group difference in the median duration of ATD treatment in the remission and relapse groups (4.4 vs 3.9 years). Of the 10 patients who relapsed, 4 (40.0%) relapsed within 2 years after ATD discontinuation, and 4 (40.0%) relapsed more than 5 years after ATD discontinuation. Conclusions The persistence of negative TRAb at ATD treatment cessation might indicate prolonged duration of remission but does not increase the final remission rate in patients with childhood-onset GD.

Introduction The treatment strategies for a 42‐year‐old female index patient with moderate Graves’ disease (GD) vary according to several international surveys. The important question whether surveys of treatment preferences in theoretical patient cases also match how real patients are treated has not yet been addressed. Materials and Methods From a Swedish cohort of 1186 GD patients (TT‐12 cohort), 27 women were identified using the same criteria as from the index patient surveys from the European and American Thyroid Associations. This ‘index patient cohort’ was age 40–45, otherwise healthy female, with two children and uncomplicated GD. The applied first‐line treatment of the patients in the index cohort, together with its variations, was compared with the treatment preferences according to international surveys. A comparison with the TT‐12 cohort was also performed. Results In the ‘Index cohort’, 77.8% were treated with antithyroid drugs (ATD), and 22.2% were treated with radioiodine (131I). This preference for ATD is in line with most countries/regions, with the exception of USA and the Middle East/North Africa, where 131I was preferred. The distribution of treatment in the TT‐12 cohort did not significantly differ from the index cohort. ATD was the preferred treatment in male and young (age 19–22) patients, as was RAI in old (age 69–73) patients. The age‐related, but not the gender‐related, cases differed significantly from the entire TT‐12 cohort. Conclusion The treatment choice in an index patient in Sweden seems in line with European practice, where ATD is the preferred first choice. This differs compared to US and North African survey intentions, where 131I is more often used. Age more than gender influences the treatment choice of GD patients. This is, to our best knowledge, the first time an index patient from ‘real life’ has been presented and compared to treatment preferences of international thyroid association surveys., According to several international surveys, the treatment strategies for a 42‐year‐old female index patient with moderate Graves’ disease vary considerably. In this study, the correlation of treatment strategies between patients from the Swedish thyrotoxicosis 2012 study cohort, who met the criteria for the index patient and its variations, and the theoretical index patient in international surveys is examined and compared. This is in order to allow a reasonable comparison with and, if possible, to validate the international surveys.

Summary Background Population studies on the prevalence of thyroid dysfunctions are costly. The pharmacy dispensing (PDR) and diagnosis (DR) registers allow us to study the epidemiology of these pathologies in a simpler way. Our aims: 1/Estimate the prevalence of thyroid dysfunction in Catalonia based on data from the PDR and the DR, 2/to evaluate the concordance of the results obtained by both strategies. Methods The population studied was the one registered with the public health system in Catalonia(Catsalut). In the PDR analysis, the information obtained through the Pharmaceutical Provision file (during 2012, 2013, 2014) was used regarding the number of patients under treatment (NPT) (levothyroxine and antithyroid medication). The DR analysis (2014) was performed by ICD‐9 codes (hyperthyroidism 242 and hypothyroidism 243, 244). Results According to the NPT in the PDR analysis, the prevalence of treated hypothyroidism increased over 3 years: 2.81%(2012), 2.92%(2013) and 3.07%(2014) (P, To Estimate the prevalence of thyroid dysfunction in Catalonia based on data from the pharmacy dispensing (PDR) and diagnosis registers (DR). The PDR analysis estimated a higher hypothyroidism prevalence compared to that estimated by the DR and vice versa in the case of hyperthyroidism. Although both PDR and DR prevalence estimations of thyroid dysfunction show some degree of discordance, both approaches are valid and complementary for estimating the prevalence of thyroid dysfunction.

Transcriptomics technologies have been used for risk assessment of chemicals, mainly to predict the modes of action (MOAs) of chemicals or identify biomarkers. Transcriptomics data may also be helpful to understand MOAs of chemicals at the molecular level in more detail. As an example of the known MOAs, there are two MOAs of thyroid toxicity: inhibition of thyroid hormone synthesis ("direct" effect) and hypermetabolism of thyroid hormone by enzyme induction in liver ("indirect" effect). In the present study, global profiles of gene expression were analyzed in rats treated with chemicals acting directly on the thyroid (thyroid peroxidase inhibitors such as propylthiouracil and methimazole) and chemicals acting indirectly on the thyroid (hepatic enzyme inducers such as phenobarbital and pregnenolone-16α-carbonitrile) using microarrays. Using a subtraction method between these two types of chemicals, we identified characteristic gene expression changes on the thyroid hormone synthesis pathway by direct-acting chemicals. Based on the functions of these genes, alterations of their expression seem to indicate the results of thyroid peroxidase inhibition, and might be helpful in more accurate evaluation of MOAs for thyroid toxicity.

Background Thyrotoxicosis, most often caused by Graves' disease (GD), when treated inadequately may result in premature mortality. There is little consensus as to which of the 3 treatment options available - antithyroid drugs (ATD), radioactive iodine (RAI) and surgery, is better. Aims (i) To assess factors involved in treatment choice and treatment satisfaction in patients treated for Graves' disease; (ii) To assess quality of life (QoL) following treatment of Graves' disease. Method Participants were selected from a prospective study cohort assessing thyrotoxicosis incidence and severity. Of the 172 eligible patients with Graves' disease, 123 treated patients participated (64% had received ATD only, 11% RAI and 25% total thyroidectomy, the latter 2 usually after a period of ATD), along with 18 untreated patients with newly diagnosed Graves' disease (overall participation rate, 73%). Consented patients completed a questionnaire detailing factors involved in treatment choice, QoL and satisfaction with treatment. Results Participants reported that the most important factors in choosing a treatment were the following: the effects on activities of daily living, concern about use of radioiodine, possibility of depression or anxiety, and doctor's recommendations. Satisfaction levels were high across all 3 treatment types. QoL 1-year following treatment was higher than in untreated patients, and comparable with other international studies. Conclusions Patient satisfaction with therapy and QoL does not differ by treatment type. Therefore, clinical and social factors, in combination with patient choice and resource availability, should determine which treatment modality patients with Graves' disease should receive.

Aims To determine the impact of hypothyroidism on the bladder and urethral functions as well as in the activation of the pubococcygeous (Pcm) and bulbospongiosus (Bsm) during micturition. Methods Age-matched control and methimazole-induced hypothyroid female rabbits were used to simultaneously record cystometrograms, urethral pressure, and the reflex activation of Pcm and Bsm during the induced micturition. Urodynamic and urethral variables were measured. Activation or no activation of the Pcm and Bsm during the storage and voiding phases of micturition were categorized as 1 or 0. Significant differences (P ≤ 0.05) between control and hypothyroid groups were determined with unpaired Student-t or Mann-Whitney tests. Results One-month induced hypothyroidism increased the residual volume and threshold pressure while the opposite was true for the voided volume, maximal pressure, and voiding efficiency. Urethral pressure was also affected as supported by a notorious augmentation of the urethral resistance, among other changes in the rest of measured variables. Hypothyroidism also affected the reflex activation of the Pcm in the voiding phase of micturition. Conclusions Our findings demonstrate hypothyroidism impairs the bladder and, urethral functions, and reflex activation of Pcm and Bsm affecting the micturition in female rabbits.

Antithyroid drugs (ATDs) are widely used for the treatment of Graves' disease (GD) in the general population. Over the past decade, there has been an increasing awareness that several disturbances of thyroid function may occur in mothers after delivery which may be more prevalent than previously appreciated. Exacerbation of immune reactions occurs 3-12 month following delivery. Management of hyperthyroidism during lactation requires special considerations and should be implemented to prevent any adverse outcomes in mother and neonate. Continuation of breastfeeding is safe and should be encouraged in hyperthyroid mothers taking ATDs, whether these are ATDs being continued after gestation or indeed ATD treatment initiated in the postpartum period. Given PTU hepatotoxicity concerns, experts currently recommend using low-to-moderate MMI doses as a first-line therapy in lactating mothers. PTU should be reserved only as a second-line agent for cases of severe hyperthyroidism (thyroid storm) and allergic reactions to previous MMI treatment. ATD should be administered in divided doses immediately following each feeding. Evaluation of thyroid function tests is advisable at least 3-4 weeks after the initiation of breastfeeding.

Background and objectives Management options are limited for the treatment of Graves' disease, and there is controversy regarding optimal treatment. We describe the demographic and biochemical characteristics of children with Graves' disease and the outcomes of its management. Methods This is a retrospective study reviewing medical records from 2001 to 2011 at a tertiary-care paediatric hospital. Diagnostic criteria included elevated free T4 and total T3, suppressed TSH, and either positive thyroid-stimulating immunoglobulin or thyroid receptor antibodies or clinical signs suggestive of Graves' disease, for example exophthalmos. Patients were treated with antithyroid drugs (ATD), radioactive iodine, or thyroidectomy. The main outcome measures were remission after medical therapy for at least 6 months and subsequent relapse. Results A total of 291 children met diagnostic criteria. A total of 62 were male (21%); 117 (40%) were Hispanic, 90 (31%) Caucasian, and 59 (20%) African American. Mean age (±standard deviation) at diagnosis was 12·3 ± 3·8 (range 3-18·5) years. At diagnosis, 268 patients were started on an antithyroid drug and 23 underwent thyroid ablation or thyroidectomy. Fifty-seven (21%) children achieved remission and 16 (28%) of these patients relapsed, almost all within 16 months. Gender and ethnicity did not affect rates of remission or relapse. Of 251 patients treated with methimazole, 53 (21%) had an adverse reaction, including rash, arthralgias, elevated transaminases, or neutropenia. Conclusions Most children with Graves' disease treated with ATD do not experience remission, but most remissions do not end in relapse. Adverse reactions to methimazole are common but generally mild.

© 2015, The American Society for Clinical Pharmacology and Therapeutics.Thioamides antithyroid-drugs (ATDs) are important in hyperthyroid disease management. Identification of the susceptibility locus of ATD-induced agranulocytosis is important for clinical management. We performed a genome-wide association study (GWAS) involving 20 patients with ATD-induced agranulocytosis and 775 healthy controls. The top finding was further replicated. A single-nucleotide polymorphism (SNP), rs185386680, showed the strongest association with ATD-induced agranulocytosis in GWAS (odds ratio (OR) = 36.4; 95% confidence interval (CI) = 12.8-103.7; P = 1.3 × 10 -24) and replication (OR = 37; 95% CI = 3.7-367.4; P = 9.6 × 10 -7). HLA-B∗38:02:01 was in complete linkage disequilibrium with rs185386680. High-resolution HLA typing confirmed that HLA-B∗38:02:01 was associated with carbimazole (CMZ)/methimazole (MMI)-induced agranulocytosis (OR = 265.5; 95% CI = 27.9-2528.0; P = 2.5 × 10 -14), but not associated with propylthiouracil (PTU). The positive and negative predictive values of HLA-B∗38:02:01 in predicting CMZ/MMI-induced agranulocytosis were 0.07 and 0.999. Approximately 211 cases need to be screened to prevent one case. Screening for the risk allele will be useful in preventing agranulocytosis in populations in which the frequency of the risk allele is high.

Uncorrected thyroid dysfunction in pregnancy has well-recognized deleterious effects on foetal and maternal health. The early gestation period is one of the critical foetal vulnerability during which maternal thyroid dysfunction may have lasting repercussions. Accordingly, a pragmatic preconception strategy is key for ensuring optimal thyroid disease outcomes in pregnancy. Preconception planning in women with hypothyroidism should pre-empt and mirror the adaptive changes in the thyroid gland by careful levothyroxine dose adjustments to ensure adequate foetal thyroid hormone delivery in pregnancy. In hyperthyroidism, the goal of preconception therapy is to control hyperthyroidism while curtailing the unwanted side effects of foetal and maternal exposure to antithyroid drugs. Thus, pregnancy should be deferred until a stable euthyroid state is achieved, and definitive therapy with radioiodine or surgery should be considered in women with Graves' disease planning future pregnancy. Women with active disease who are imminently trying to conceive should be switched to propylthiouracil either preconception or at conception in order to minimize the risk of birth defects from carbimazole or methimazole exposure. Optimal strategies for women with borderline states of thyroid dysfunction namely subclinical hypothyroidism, isolated hypothyroxinaemia and thyroid autoimmunity remain uncertain due to the dearth of controlled interventional trials. Future trial designs should aspire to recruit and initiate therapy before conception or as early as possible in pregnancy.

SummaryObjective Thyroid storm (TS) is a life-threatening endocrine emergency. This study aimed to achieve a better understanding of the management of TS by analyzing therapeutic modalities and prognoses reported by nationwide surveys performed in Japan. Design, patients and measurements Retrospective analyses were performed on clinical parameters, outcomes, and treatments in 356 TS patients. Results Patient disease severities assessed via Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores significantly correlated with mortality. Free triiodothyronine (FT3) and the FT3/free thyroxine (FT4) ratio inversely correlated with disease severity. Methimazole (MMI) was used in the majority of patients (78·1%), and there were no significant differences in mortality or disease severity between those treated with MMI and those receiving propylthiouracil (PTU). Patients who received inorganic iodide (KI) demonstrated higher disease severity but no change in mortality compared to those who did not. Patients treated with corticosteroids (CSs) demonstrated significantly higher disease severity and mortality than those who were not. Disease severity in patients treated with intravenous administration of beta-adrenergic antagonists (AAs) was significantly higher than those treated with oral preparations, although no significant difference in mortality was observed between these groups. In addition, mortality was significantly higher in patients treated with non-selective beta-AAs as compared with other types of beta-AAs. Conclusion In Japan, MMI was preferentially used in TS and showed no disadvantages compared to PTU. In severe TS, multimodal treatment, including administration of antithyroid drugs, KI, CSs and selective beta1-AAs may be preferable to improve outcomes.

The treatment options in the young patient with Graves' disease are the same as in adults, namely antithyroid drug (ATD), surgery (partial or total thyroidectomy) and radioiodine. However, the emphasis and expectation is different in the young person, reflecting a range of considerations including age, pubertal status, disease natural history, likely impact of ATD on disease course and the implications of radiation exposure. New therapeutic strategies that could increase the likelihood of long-term remission are being explored.

SummaryObjective Management of Graves' disease (GD) in Europe was published in 1987. Aim of this survey was to provide an update on clinical practice in Europe, and to compare it with a 2011 American survey. Design Members of the European Thyroid Association (ETA) were asked to participate in a survey on management of GD, using the same questionnaire of a recent American survey. Results A total of 147 ETA members participated. In addition to serum TSH and free T4 assays, most respondents would request TSH-receptor autoantibody (TRAb) measurement (85·6%) and thyroid ultrasound (70·6%) to confirm aetiology, while isotopic studies were selected by 37·7%. Antithyroid drug (ATD) therapy was the preferred first-line treatment (83·8%). Compared to the previous European survey, Europeans currently more frequently use TRAb measurement and thyroid ultrasound for diagnosis and evaluation, but first-line treatment remains ATDs in a similar percentage of respondents. Current clinical practice patterns differ from those in North America, where isotopic studies are more frequently used, and radioiodine (RAI) still is first-line treatment. When RAI treatment is selected in the presence of mild Graves' orbitopathy and/or associated risk factors for its occurrence/exacerbation, steroid prophylaxis is frequently used. The preferred ATD in pregnancy is propylthiouracil in the first trimester and methimazole in the second and third trimesters, similar to North America. Conclusions Significant changes in clinical practice patterns in Europe were noted compared to the previous European survey, as well as persisting differences in diagnosis and therapy between Europe and North America.

Feline hyperthyroidism is a common endocrine disorder in older cats for which homeopathic treatment has been advocated. A double-blinded, placebo-controlled randomised trial was performed to look for evidence of efficacy for the use of individualised homeopathy in the treatment of this disease. Using a case definition of a concentration of the thyroid hormone T4 >66 nmol/l, cats were randomised into two treatment arms. Either a placebo or a homeopathic treatment was given to each cat blindly. After 21 days, the T4 levels, weight (Wt) and heart rate (HR) were compared with pretreatment values. There were no statistically significant differences in the changes seen between the two treatment arms following placebo or homeopathic treatment (T4 P=0.96, Wt P=0.16, HR P=0.36) or between the means of each parameter for either treatment arm before and after placebo or homeopathic treatment (all P values >0.13). In a second phase of the study, patients in both treatment arms were given methimazole treatment for 21 days and T4, Wt and HR determined again. Again there were no statistically significant differences between the groups, but there were statistically significant reductions in T4 (P

Pha rmacological management of feline hyperthyroidism offers a practical treatment option for many hyperthyroid cats. Two drugs have been licensed for cats in the last decade: methimazole and its pro-drug carbimazole. On the basis o f current evidence and available tablet sizes, starting doses of 2·5 mg methimazole twice a day and 10 to 1 5 mg once a day for the sustained release formulation of carbimazole are recommended. These doses should then be titrated to effect in order to obtain circulating total thyroxine (TT4) concentrations in the lower half of the reference interval. Treated cases should be monitored for side-effects, especially during the first months of treatment. Some side-effects may require discontinuation of treatment. At eac h monitoring visit, clinical condition and quality of life should also be evaluated, with special attention to possible development of azotaemia, hypertension and iatrogenic hypothyroidism. When euthyroidism has been achieved, monitoring visits are recommended after 1 month, 3 months and biannually thereafter. Cats with pre-existing azotaemia have shorter survi val times. However, development of mild azotaemia during the initial course of treatment, unless associated with hypothyroidism, does not appear to decrease survival time. The long-term effects of chronic medic al management require further study.

Feline hyperthyroidism can be treated medically, surgically or with radioactive iodine. Carbimazole inhibits both triiodothyronine and thyroxine synthesis in the thyroid gland and reported side effects include mild eosinophilia, leucopenia and lymphocytosis, thrombocytopenia, elevated liver enzyme activities, gastrointestinal signs and skin abnormalities. This case report describes a cat with carbimazole-associated apparent hypersensitivity vasculitis causing digital and tail necrosis, with multiple renal infarcts. Withdrawal of carbimazole resulted in stable disease.

Although thyroid-stimulating hormone (TSH) is known to be a major regulator of thyroid hormone biosynthesis and thyroid growth, insulin-like growth factor 1 (IGF-1) is required for mediating thyrocyte growth in concert with TSH in vitro. We generated mice with thyrocyte-selective ablation of IGF-1 receptor (TIGF1RKO) to explore the role of IGF-1 receptor signaling on thyroid function and growth. In 5-wk-old TIGF1RKO mice, serum thyroxine (T4) concentrations were decreased by 30% in concert with a 43% down-regulation of the monocarboxylate transporter 8 (MCT8), which is involved in T4 secretion. Despite a 3.5-fold increase in circulating concentrations of TSH, thyroid architecture and size were normal. Furthermore, thyrocyte area was increased by 40% in WT thyroids after 10 d TSH injection, but this effect was absent in TSH-injected TIGF1RKO mice. WT mice treated with methimazole and sodium perchlorate for 2 or 6 wk exhibited pronounced goiter development (2.0 and 5.4-fold, respectively), but in TIGF1RKO mice, goiter development was completely abrogated. These data reveal an essential role for IGF-1 receptor signaling in the regulation of thyroid function and TSH-stimulated goitrogenesis.

BACKGROUND: Transdermal methimazole is an acceptable alternative to oral treatment for hyperthyroid cats. There are, however, no studies evaluating the duration of T4 suppression after transdermal methimazole application. Such information would be valuable for therapeutic monitoring. OBJECTIVE: To assess variation in serum T4 concentration in hyperthyroid cats after once- and twice-daily transdermal methimazole administration. ANIMALS: Twenty client-owned cats with newly diagnosed hyperthyroidism. METHODS: Methimazole was formulated in a pluronic lecithin organogel-based vehicle and applied to the pinna of the inner ear at a starting dose of 2.5 mg/cat q12h (BID group, 10 cats) and 5 mg/cat q24h (SID group, 10 cats). One and 3 weeks after starting treatment, T4 concentrations were measured immediately before and every 2 hours after gel application over a period of up to 10 hours. RESULTS: Significantly decreased T4 concentrations were observed in week 1 and 3 compared with pretreatment concentrations in both groups. All cats showed sustained suppression of T4 concentration during the 10-hour period, and T4 concentrations immediately before the next methimazole treatment were not significantly different compared with any time point after application, either in the BID or SID groups. CONCLUSIONS: Because transdermal methimazole application led to prolonged T4 suppression in both the BID and SID groups, timing of blood sampling does not seem to be critical when assessing treatment response.

Clinical hyperthyroidism has been associated with an increased risk of maternal, fetal, and neonatal complications. The available antithyroid drugs are methimazole/carbimazole and propylthiouracil. Several case reports and some epidemiologic studies suggest that methimazole/carbimazole exposure during the first trimester of pregnancy is associated with an increased risk of congenital malformations, including ectodermal anomalies, choanal atresia, esophageal atresia, and omphalocele. However, the absolute risk appears to be very small, and it remains unclear whether the association is driven by the maternal disease, the medication, or the combination of both factors. Propylthiouracil exposure has not been associated with an increased risk of congenital malformations and is the recommended drug during the first trimester of pregnancy. Since propylthiouracil-induced hepatotoxicity has been reported in approximately 0.1% of exposed adults and the number of case-reports of severe liver injury is increasing, treatment with low dose methimazole during the second and third trimesters should be considered. Until now, there has been no evidence that children prenatally exposed to methimazole/carbimazole or propylthiouracil have an increased risk of neurodevelopmental delay.

Thyroid hormones modulate the physiology of the hippocampus in humans, where glutamate plays an important role as neurotransmitter. The aim of this work was to study the effect of hypothyroidism on hippocampal glutamate extracellular levels, release, uptake, and synthesis. The effects of PDC (a glutamate transporter inhibitor) and ouabain (a Na(+) /K(+) -ATPase inhibitor) infusion on microdialysate glutamate and aspartate levels of CA3 hippocampal region were evaluated. Animals were assigned to one of the following groups: hypothyroid group (Hyp), receiving methimazole (anantithyroid drug); replacement group (Hyp + T(4) ), receiving antithyroid treatment plus thyroxine; and euthyroid control group (Eut). Dialysate fractions were collected every 15 min to determine basal glutamate levels for 1 hr. Then, PDC (10 mM) or ouabain (100 μM) was infused for 30 min. Results showed lower glutamate and aspartate basal levels in Hyp than in Eut groups. PDC infusion increased amino acids levels in all groups, whereas ouabain infusion increased glutamate and aspartate levels only in the Eut group. The infusion of tetrodotoxin (TTX; a voltage-gated sodium channel inhibitor) prevented the glutamate increase in euthyroid rats. The Hyp + T(4) group showed glutamate levels similar to those found in the Eut group. Additionally, glutaminase activity in hippocampus was lower in the Hyp group than in the Eut or Hyp + T(4) group. Results suggest that high-affinity glutamate transporters are not altered by hypothyroidism; however, decreased hypotyroidism reduced vesicular glutamate release in the CA3-hippocampal region as a consequence of diminished glutamate synthesis.

Background Previous studies on transdermal methimazole have used pluronic lecithin organogel as the vehicle. This might not be the most suitable vehicle for a lipophilic drug, such as methimazole. Hypothesis/Objectives Once daily transdermal administration of a novel lipophilic formulation of methimazole is as safe and effective as oral carbimazole in treating hyperthyroidism in cats. Animals Forty-five client-owned cats diagnosed with hyperthyroidism. Methods Prospective study. Cats with newly diagnosed, untreated hyperthyroidism were treated with carbimazole (5 mg PO, q12h) or methimazole (10 mg) applied to the inner pinnae q24h. Cats were examined after 0, 1, 4, 8, and 12 weeks of treatment. Clinical signs, body weight, systolic blood pressure, hematologic, serum biochemical and urine parameters, total serum thyroxine concentrations (TT4), and serum methimazole concentrations were recorded. Results No significant differences between groups were detected at day 0. Both formulations were effective in treating hyperthyroidism. No significant differences were detected in thyroxine concentrations, body weight, blood pressure, heart rate, alkaline phosphatase, alanine aminotransferase, creatinine, urea, and urine specific gravity (USG) between groups. The serum methimazole concentrations correlated poorly with TT4-concentrations in both groups. Conclusions and Clinical Importance In this 12-week trial, once daily application of a novel formulation of transdermal methimazole applied to the pinnae was as effective and safe as twice daily oral carbimazole in the treatment of cats with hyperthyroidism. This novel formulation and transdermal application could have practical advantages to some pet owners.

We investigated age-related changes in the mode of regeneration in the mouse peripheral olfactory system after olfactotoxic drug-induced damage. Mice at postnatal ages of 10 days, 3 months, and 16 months were given an intraperitoneal injection of methimazole to produce damage in the olfactory neuroepithelium. The olfactory neuroepithelia were harvested and analyzed immunohistochemically at various postlesion timepoints, from 1 day through to 94 days, to investigate neuroepithelial cell proliferation, the time course of neuronal differentiation, the reconstitution of neuroepithelium, and the innervation of the olfactory bulb. Functional recovery was assessed using the vanillin avoidance behavioral test. The chronological pattern in the expression of Ki67, beta III tubulin, and olfactory marker protein, molecular markers for neuronal cell proliferation and differentiation, changed similarly among the different age groups. In contrast, the extent of neuroepithelial cell proliferation after injury decreased with age, and the final histological recovery of the olfactory neuroepithelium and the innervation of the olfactory bulb were significantly smaller in the 16-month-old group compared to the younger age groups. These results suggest that the age-related decline in the capacity of olfactory neuroepithelium to reconstitute neuroepithelium is associated with its age-related decrease in proliferative activity after the neuroepithelial injury rather than changes in the process of neuronal differentiation. In spite of these incomplete anatomical recoveries, 16-month-old mice regained the ability to avoid vanillin solution by 1 month postlesion, suggesting that the extent of anatomical epithelial damage is not necessarily proportional to the threshold of olfactory perception.

Follicular thyroglobulin (TG) reflects the storage of both iodine and thyroid hormone. This is because it is a macromolecular precursor of thyroid hormone and organic iodinated compound in follicular lumen. Thus, it may have an important feedback role in thyroid function. In this study, monolayer cells were cultured and follicles were reconstituted with primary pig thyroid cells in vitro. Reconstituted follicles were treated with iodine and methimazole (MMI), a drug that blocks iodine organification and reduces the degree of TG iodination in follicular lumen. The high degree of iodinated TG in follicular lumen was observed to inhibit thyroid-restricted gene expression. To confirm this finding, monolayer thyroid cells were treated with a different degree of TG iodination at the same concentration. These iodinated TG were extracted from reconstituted follicles of different groups. In this manner, this study provides firsthand evidence suggesting that follicular TG inhibits the expressions of thyroid-restricted genes NIS, TPO, TG, and TSHr.

The effects of ATP, ADP, and adenosine in the processes of platelet aggregation, vasodilatation, and coronary flow have been known for many years. The sequential hydrolysis of ATP to adenosine by soluble nucleotidases constitutes the main system for rapid inactivation of circulating adenine nucleotides. Thyroid disorders affect a number of biological factors including adenosine levels in different fractions. Then, we intend to investigate if the soluble nucleotidases responsible for the ATP, ADP, and AMP hydrolysis are affected by variations in the thyroid hormone levels in blood serum from adult rats. Hyperthyroidism was induced by daily intraperitoneal injections of L-thyroxine (T4) (2.5 and 10.0 μg/100 g body weight, respectively) for 7 or 14 days. Hypothyroidism was induced by thyroidectomy and methimazole (0.05%) added to their drinking water during 7 or 14 days. The treatments efficacy was confirmed by determination of hemodynamic parameters and cardiac hypertrophy evaluation. T4 treatment predominantly inhibited, and hypothyroidism (14 days after thyroidectomy) predominantly increased the ATP, ADP, and AMP hydrolysis in rat blood serum. These results suggest that both excess and deficiency of thyroid hormones can modulate the ATP diphosphohydrolase and 5'-nucleotidase activities in rat blood serum and consequently modulate the effects mediated by these enzymes and their products in vascular system.

More than any other neuron, olfactory sensory neurons are exposed to environmental insults. Surprisingly, their only documented response to damaging stress is apoptosis and subsequent replacement by new neurons. However, they expressed unfolded protein response genes, a transcriptionally regulated defense mechanism activated by many types of insults. The unfolded protein response transcripts Xbp1, spliced Xbp1, Chop (Ddit3), and BiP (Hspa5) were decreased when external access of stressors was reduced by blocking a nostril (naris occlusion). These transcripts and Nrf2 (Nfe2l2) were increased by systemic application of tunicamycin or the selective olfactotoxic chemical methimazole. Methimazole's effects overcame naris occlusion, and the unfolded protein response was independent of odor-evoked neuronal activity. Chemical stress is therefore a major and chronic activator of the unfolded protein response in olfactory sensory neurons. Stress-dependent repression of the antiapoptotic gene Bcl2 was absent, however, suggesting a mechanism for disconnecting the UPR from apoptosis and tolerating a chronic unfolded protein response. Environmental stressors also affect both the sustentacular cells that support the neurons and the respiratory epithelia, because naris occlusion decreased expression of the xenobiotic chemical transformation enzyme Cyp2a5 in sustentacular cells, and both naris occlusion and methimazole altered the abundance of the antibacterial lectin Reg3g in respiratory epithelia.

The role of thyroid hormones in testis structure and function has been fairly well studied in laboratory rodents. However, there are no comprehensive data in the literature for mice regarding the effects of transiently induced neonatal hypo- and hyperthyroidism on testis and spermatogonial cell development from birth to adulthood. Our goals were to evaluate the effects of propylthiouracil (PTU) and triidothyronine (T3) on Sertoli cell proliferation/differentiation and to correlate these events with the evolution of the spermatogenic process, tubular lumen formation, blood vessel volume density, and size and number of different spermatogonial types. Although Sertoli cell maturation was accelerated or delayed, respectively, in T3- and PTU-treated mice, the pace of the germ cell maturation was only slightly altered before puberty and the period of Sertoli cell proliferation was apparently not affected by the treatments. However, compared with controls, the total number of Sertoli cells per testis from 10 days of age to adulthood was significantly increased and decreased in PTU- and T3-treated mice, respectively. In comparison to all other spermatogonia, type A(2) was the largest cell in all ages and groups investigated. The PTU-treated mice had a significantly increased total number of undifferentiated spermatogonia as well as volume and percentage of vessels/capillaries, probably due to the higher number of Sertoli cells, particularly at 10 days of age. Taken together, our results suggest that neonatal hypothyroidism may be a valuable tool for studying spermatogonial biology as well as a means for providing more spermatogonial stem cells that could potentially be used for spermatogonial transplantation, thereby optimizing the efficiency of this technique when young mice are used as donors.

The U.S. Environmental Protection Agency (U.S. EPA) has included an amphibian metamorphosis assay (AMA) to detect thyroid active chemicals in Tier 1 testing of their endocrine screening program. To understand the variability, specificity, and reliability of the key endpoints of this assay, two exposure studies with Xenopus laevis tadpoles were conducted with two known thyroid-active compounds, namely, methimazole or L-thyroxine, for a total of 21 d. In addition, various increased-flow-rate treatments were included in the exposures to evaluate the effects of physical stress on metamorphic development. The endpoints examined in the exposures were wet weight, snout-vent length, hind-limb length, developmental stage, and thyroid and gonadal histopathology. As expected, the results indicated that both methimazole and L-thyroxine were thyroid active in the AMA, hind-limb length and thyroid histopathology being the most sensitive endpoints of thyroid activity. Tadpoles that were exposed to the various physical stressors in these experiments showed no signs of altered metamorphic development, and exposure to the thyroid-active compounds had no effect on the developing gonad of X. laevis. Taken together, these results support the use of the AMA as a Tier 1 endocrine screen for detection of potential thyroid pathway activity; however, the lack of a true negative response (no-effect) during the validation process prevents a full evaluation of this assay's specificity at this time.

Thyroid hormone is essential for normal brain development, although the degree to which the developing brain is sensitive to small perturbations in serum thyroxin is not clear. An important concept related to this is that the developing brain possesses potent mechanisms to compensate for low serum thyroid hormone, and this concept is routinely employed in discussions concerning clinical treatments or public health. However, experimental studies have not directly tested whether (or the degree to which) putative compensatory mechanisms can ameliorate the consequences of small reductions in serum thyroxin (T(4)). To formally test this concept, we employed a model of graded T(4) reductions using doses of propylthiouracil (PTU) that were 200- to 67-fold lower than the dose traditionally used to produce hypothyroidism in rats. PTU produced a stepwise decrease in serum total T(4), and a stepwise increase in serum thyroid-stimulating hormone (TSH), in type 2 deiodinase mRNA expression and enzyme activity in the brain, and in the expression of the mRNA encoding the tri-iodothyronine (T(3)) transporter MCT8 in the postnatal day (P) 15 cortex. However, the mRNA encoding RC3/neurogranin, a direct target of T(3) action, exhibited a strong negative linear correlation with serum total T(4) despite these adaptive responses. In addition, single-cell analysis of RC3 mRNA levels in cortical neurones demonstrated that the co-expression of MCT8 did not alter the relationship between RC3 mRNA and serum T(4). These findings do not support the currently envisioned concept of the developing brain being capable of compensating for low T(4).

In this paper, the effect of some commonly used antithyroid drugs and their analogues on peroxynitrite-mediated nitration of proteins is described. The nitration of tyrosine residues in bovine serum albumin (BSA) and cytochromec was studied by Western blot analysis. These studies reveal that the antithyroid drugs methimazole (MMI), 6-n-propyl-2-thiouracil (PTU), and 6-methyl-2-thiouracil (MTU), which contain thione moieties, significantly reduce the tyrosine nitration of both BSA and cytochrome c. While MMI exhibits good peroxynitrite (PN) scavenging activity, the thiouracil compounds PTU and MTU are slightly less effective than MMI. The S- and Se-methylated compounds show a weak inhibitory effect in the nitration of tyrosine, indicating that the presence of a thione or selone moiety is important for an efficient inhibition. Similarly, the replacement of N-H moiety in MMI by N-methyl or N-m-methoxybenzyl substituents dramatically reduces the antioxidant activity of the parent compound. Theoretical studies indicate that the substitution of N-H moiety by N-Me significantly increases the energy required for the oxidation of sulfur center by PN. However, such substitution in the selenium analogue of MMI increases the activity of parent compound. This is due to the facile oxidation of the selone moiety to the corresponding selenenic and seleninic acids. Unlike N,N'-disubstituted thiones, the corresponding selones efficiently scavenge PN, as they predominantly exist in their zwitterionic forms in which the selenium atom carries a large negative charge.

A simple, rapid, reproducible and sensitive method based on CE with electrochemical detector was developed for the simultaneous determination of five thyreostatics including 2-thiouracil (TU), 6-methyl-2-thiouracil (MTU), 6-propyl-2-thiouracil (PTU), 6-phenyl-2-thiouracil (PhTU) and methimazole (TAP) in animal feeds. A home-made wall-jet electrochemical detector with a 300 microm diameter platinum-disk-working electrode was equipped at the end of separation capillary and used to detect oxidation currents of these thyreostatics. Under the optimum experimental conditions, TU, MTU, PTU, PhTU and TAP could be well separated within 15 min at the separation voltage of 16 kV in 20 mmol/L sodium borate buffer (pH 9.2). The detection limits (S/N=3) of the five thyreostatics in animal feeds were found to be 7.6 microg/kg for TAP, 25 microg/kg for PTU, 15 microg/kg for PhTU, 18 microg/kg for TU and 20 microg/kg for MTU by the developed CE with electrochemical detector method coupled with solid-phase extraction sample pretreatment technique.

Methimazole suppresses thyroid hormone synthesis and is commonly used to treat feline hyperthyroidism. The degree of variation in thyroid hormone concentrations 24 hours after administration of methimazole and optimal time for blood sampling to monitor therapeutic efficacy have not been determined.To assess thyroid hormone concentration variation in serum of normal and hyperthyroid cats after administration of methimazole.Four healthy cats and 889 retrospectively acquired feline thyroid hormone profiles.Crossover and retrospective studies. In the crossover study, healthy cats were treated with increasing doses of oral methimazole until steady state of thyroid suppression was achieved. Thyroid hormones and thyroid stimulating hormone (TSH) were serially and randomly monitored after methimazole. Paired t-tests and a 3-factor analysis of variance were used to determine differences between thyroid hormone concentrations in treated and untreated cats in the crossover study. Thyroid profiles from methimazole-treated hyperthyroid cats were retrieved from the Diagnostic Center for Population and Animal Health database and reviewed. Linear regression analysis evaluated relationships of dosage (mg/kg), dosing interval (q24h versus q12h), and time after methimazole to all thyroid hormone concentrations.All serum concentrations of thyroid hormones were significantly suppressed and TSH was significantly increased for 24 hours after administration of oral methimazole in healthy cats (P.005). In hyperthyroid cats, there were no significant relationships between thyroid hormone concentrations and time postpill or dosing interval.Timing of blood sampling after oral methimazole administration does not appear to be a significant factor when assessing response to methimazole treatment.

Summary Background Thyroid disorders are frequent in patients with Down syndrome (DS). It is well-known that the prevalence of hypo- thyroidism is high but data on hyperthyroidism are scarce. Objectives To assess the prevalence, aetiology, clinical characteristics, evolution and treatment of hyperthyroidism in a population with DS attending a specialized medical centre. Methods Data were gathered by systematic review of 1832 medical records from the Catalan DS Foundation, in Spain, registered between January 1991 and February 2006. Patients with the diagnosis of hyperthyroidism were identified and data on clinical features, physical examination, laboratory and imaging tests, treatment and evolution were collected. Results Twelve patients with hyperthyroidism were recorded (6·5 cases/1000 patients with DS). There were 5 males and 7 females, with a mean age at diagnosis of 16·8 years. The most common presenting symptoms were decreased heat tolerance, sweating, increased irritability and weight loss. All patients had diffuse goitre at physical examination and two patients presented with exophthalmia. Clinical diagnosis was confirmed biochemically. Thyroid-stimulating immunoglobulin levels were raised (mean 128·1 U/l) and imaging tests confirmed the diagnosis of Graves' disease in all cases. Patients started treatment with carbimazole at diagnosis and after a mean period of 40 months without clinical remission, they required definitive therapy with radioactive iodine. Subjects developed hypothyroidism after radio-iodine therapy and replacement therapy with levothyroxine was necessary. Conclusions Hyperthyroidism is more prevalent in patients with DS than in the general population and has no gender predominance. It is caused mainly by Graves' disease. Anti-thyroid drugs were not effective in achieving remission and radioactive iodine as a definitive treatment was required in all cases.

Twenty-seven patients with Graves' disease and progressive ophthalmopathy in an advanced stage underwent a transtemporal orbital decompression. The short-term results, i.e. within 2 months, of 48 operations are reported. Prior to the decompression, oral prednisolone, 20–60 mg daily, was given for 2 to 9 months to 15 patients. A minority of patients experienced temporary improvement during steroid administration. Cushing's syndrome was initiated in all patients. Prednisolone little altered the course of the progressive ophthalmopathy. Orbital decompression was followed by increasing visual acuity in 8/22 eyes with disturbed vision, a temporary decrease in 6 eyes, and unaltered visual acuity in the remaining 8 eyes. The decompression removed oedema of the optic disc in all eyes, cured glaucoma in 3 out of 5 patients, caused retraction of the eye bulbs by 5–6 mm in almost all operated cases, and increased compressibility of the orbital content from low (2–5 mm) to normal (6–10 mm) values. Surgery also relieved photophobia and lacrimation, but the effect on diplopia was uncertain. Generally, the decompression was followed by a rapid improvement of the orbital congestion and the patients recovered satisfactorily from the surgery.

The ocular manifestations in 125 thyrotoxic patients observed for 6-20 years are presented. The incidence and development of ophthalmopathy in three different treatment group medical- (eta = 72), radionuclear (eta = 36) and surgical (eta = 17) are showed. The degree of ophthalmopathy is similar in all groups, and no statistically significant difference is found in the development of ophthalmopathy.

The records of 133 patients, discharged with a diagnosis of "agranulocytosis" (i.e. blood neutrophil levels less than 1.0 x 109/1) during the years 1973-75 in the Stockholm county region, were reviewed. In 45 cases the neutropenia was probably caused by drugs other than cytostatics, giving an annual incidence of drug-induced neutropenia of 0.01%. The most common drugs were thenalidine, sulfonamides and thyreostatics. Only one of the 45 patients died during the neutropenic phase. It is concluded that the pattern of drugs causing neutropenia has changed in Sweden compared with studies from the latter half of the 1960's, and only about 40% of the cases have been reported to the authorities.

In hyperthyroidism thyroid antibodies (thyroglobulin antibody and/or microsomal antibody) have been found in 30% of 44 patients examined before treatment was started, in 22% of 41 patients treated with antithyroid drugs, and in 21% of 34 patients who had previously undergone partial thyroidectomy. In a few patients there was a rather abrupt fall in the concentration of thyroglobulin antibody during treatment with antithyroid drugs. As this might possibly have been due to a neutralization of the antibody in vivo, a number of sera which did not contain thyroglobulin antibody were investigated for circulating thyroglobulin. This investigation revealed thyroglobulin activity in the sera of 11 out of 18 patients who were receiving antithyroid drug therapy and in five out of 11 patients from whom antithyroid therapy had been withdrawn, but only in two out of 18 patients who had previously undergone partial thyroidectomy. Isolation experiments would suggest that the substance demonstrated might be genuine thyroglobulin, but—at least in some cases—with a lower iodine content than normal thyroglobulin. It is discussed whether the presence of this iodine-poor thyroglobulin-like protein and its breakdown products might not provide an explanation of the low PBI concentrations which are occasionally seen in patients during treatment with antithyroid drugs, once they have reached the euthyroid state.

BACKGROUND: Until now, it remains elusive which strategy - antithyroid drug withdrawal or increased radioiodine target doses - should be preferred to avoid the detrimental effect of antithyroid drugs in high- and low-dose radioiodine therapy, respectively. METHODS: We explored the effects of carbimazole on the 1-year post-radioiodine success and hypothyroidism rates by continuous dose-effect models, whereas success was defined as elimination of hyperthyroidism. Euthyroidism rates with and without carbimazole were calculated by numerical integration of the area between success and hypothyroidism curves. Target dose amplification factors for equal chance of success with and without carbimazole were calculated using logistic regression. RESULTS: Two hundred and twenty-eight patients were included in this study. Radioiodine target doses between 33 and 839 Gy were applied. Overall, the euthyroidism rates were 16.5% and 64.8%, while the hypothyroidism rates were 37.6% and 14.8% in Graves' disease and toxic nodular goitre, respectively. The success rate with simultaneous carbimazole (median dose 15 mg day(-1); range 2.5-60 mg day(-1)) was reduced over the entire target dose range in Graves' disease and toxic nodular goitre. The areas between curves for euthyroidism without and with simultaneous carbimazole were 127 and 43 Gy in Graves' disease and 178 and 128 Gy in toxic nodular goitre. The estimated radioiodine target dose amplification factor was 5.5 for Graves' disease and 3.0 for toxic nodular goitre. CONCLUSIONS: Simultaneous carbimazole reduces the euthyroidism rate, the aim of low-dose radioiodine therapy, over the entire target dose range in both Graves' disease and toxic nodular goitre. Therefore, antithyroid drug discontinuation should be preferred in low-dose radioiodine therapy. Conversely, escalation of the target dose should be preferred in high-dose radioiodine therapy

Summary Background An association between radioiodine therapy (RAI) for Graves’ disease (GD) and the development or worsening of Graves’ ophthalmopathy (GO) is widely quoted but there has been no systematic review of the evidence. Aims We undertook a systematic review of randomized controlled trials (RCTs) to assess whether RAI for GD is associated with increased risk of ophthalmopathy compared with antithyroid drugs (ATDs) or surgery. We also assessed the efficacy of glucocorticoid prophylaxis in the prevention of occurrence or progression of ophthalmopathy, when used with RAI. Methods We identified RCTs regardless of language or publication status by searching six databases and trial registries. Dual, blinded data abstraction and quality assessment were undertaken. Random effects meta-analyses were used to combine the study data. Ten RCTs involving 1136 patients permitted 13 comparisons. Two RCTs compared RAI with ATD. Two RCTs compared RAI with thyroidectomy. Four RCTs compared the use of adjunctive ATD with RAI vs. RAI. Five RCTs examined the use of glucocorticoid prophylaxis with RAI. Results RAI was associated with an increased risk of ophthalmopathy compared with ATD [relative risk (RR) 4·23; 95% confidence interval (CI): 2·04 ‐8 ·77] but compared with thyroidectomy, there was no statistically significant increased risk (RR 1·59, 95% CI 0·89‐2·81). The risk of severe GO was also increased with RAI compared with ATD (RR 4·35; 95% CI 1·28‐14·73). Prednisolone prophylaxis for RAI was highly effective in preventing the progression of GO in patients with pre-existing GO (RR 0·03; 95% CI 0·00‐0·24). The use of adjunctive ATD with RAI was not associated with any significant benefit on the course of GO. Conclusion RAI for GD is associated with a small but definite increased risk of development or worsening of Graves’ ophthalmopathy compared with ATDs. Steroid prophylaxis is beneficial for patients with pre-existing GO.

Thyroid hormone (TH) deficiency during perinatal life causes a multitude of functional and morphological deficits in the brain. In rats and mice, TH dependency of neural maturation is particularly evident during the first 1-2 weeks of postnatal development. During the same period, synaptic transmission via the inhibitory transmitters glycine and GABA changes from excitatory depolarizing effects to inhibitory hyperpolarizing ones in most neurons [depolarizing-hyperpolarizing (D/H) shift]. The D/H shift is caused by the activation of the K(+)-Cl(-) co-transporter KCC2 which extrudes Cl(-) from the cytosol, thus generating an inward-directed electrochemical Cl(-) gradient. Here we analyzed whether the D/H shift and, consequently, the onset of inhibitory neurotransmission are influenced by TH. Gramicidin perforated-patch recordings from auditory brainstem neurons of experimentally hypothyroid rats revealed depolarizing glycine effects until postnatal day (P)11, i.e. almost 1 week longer than in control rats, in which the D/H shift occurred at approximately P5-6. Likewise, until P12-13 the equilibrium potential E(Gly) in hypothyroids was more positive than the membrane resting potential. Normal E(Gly) could be restored upon TH substitution in P11-12 hypothyroids. These data demonstrate a disturbed Cl(-) homeostasis following TH deficiency and point to a delayed onset of synaptic inhibition. Interestingly, immunohistochemistry demonstrated an unchanged KCC2 distribution in hypothyroids, implying that TH deficiency did not affect KCC2 gene expression but may have impaired the functional status of KCC2. Hippocampal neurons of hypothyroid P16-17 rats also demonstrated an impaired Cl(-) homeostasis, indicating that TH may have promoted the D/H shift and maturation of synaptic inhibition throughout the brain.

Summary Context Management of Graves’ orbitopathy (GO) and dysthyroid optic neuropathy (DON) continues to be challenging. Other surveys have been successful in elucidating trends in GO management. Knowledge of current practice by members of the Latin American Thyroid Society (LATS) who manage patients with GO was targeted by distribution of a questionnaire. We compared our results with a previously reported European Thyroid Association (ETA) survey. Objectives To determine how endocrinologists in Latin America access and treat patients with GO and compare the results with the same European survey. Results One hundred and two responders representing endocrinologists from 10 countries participated in the survey. Most (57%) participate in a multidisciplinary setting for GO management. Access to a surgeon for orbital decompression was available only ‘within months’ according to 48·3% of responders. Despite suspected DON, 32·4% were reluctant to recommend urgent referral to an eyecare physician. Steroids were preferred as the first-option therapy by 88·2% of responders (by intravenous route by 57·8% of these). The presence of diabetes reduced the use of steroids to 64·7% (P