Optimization of 131I ablation in patients with differentiated thyroid carcinoma: comparison of early outcomes of treatment with 100 mCi versus 60 mCi

INTRODUCTION: The aim of this study was to compare the early outcomes between two groups of patients with differentiated thyroid carcinoma (DTC) who received 60 or 100 mCi of (131)I for remnant ablation. MATERIAL AND METHODS: 224 DTC patients with primary tumor > 1 cm of diameter or multifocal were randomised into prospective clinical trial. Patients with extrathyroideal extension of primary tumor and nodal metastases or M1 were not enrolled. 99 patients received 60 mCi, and 125--100 mCi of radioiodine as the first ablative dose. RESULTS: The effectiveness of thyroid ablation was evaluated after one year, during endogenous TSH (thyroid stimulating hormone) stimulation, and after two years during Lthyroxine therapy. Whole body scintigraphy (WBS) was performed under thyroxine withdrawal and thyroglobulin serum level was assessed. Distant micrometastases were detected in 9.8% of patients by post-therapy WBS, 11 patients in group A treated with 60 mCi and 11 in group B treated with 100 mCi. In other patients no symptoms of persistent disease were detected. At one year follow up full remission was diagnosed in 176 patients: 76 in group A and 100 in group B. The remaining ones, 13.3% and 11.2% respectively, received the second course of (131)I for remnant ablation. There were no statistically significant differences in Tg (thyroglobulin) serum level either 12 or 24 months after 131I treatment. CONCLUSIONS: Our evaluation of early efficacy of adjuvant radioiodine treatment in low risk DTC patients shows no differences between two radioiodine activities - 60 and 100 mCi in relation to thyroid ablation. Thus, the activity of 60 mCi is recommended.     

Recombinant human TSH stimulation in radioiodine treatment of disseminated differentiated thyroid cancer--update of current and our own experiences

Traditionally, for diagnostic and therapeutic application of radioiodine in patients with differentiated thyroid cancer (DTC), a 4 to 6 week withdrawal of thyroid hormone was applied. Recombinant human TSH (rhTSH) was developed to provide TSH stimulation without withdrawal of thyroid hormone and associated morbidity. The results of rhTSH administration and endogenous TSH stimulation are equivalent in detecting recurrent DTC. At the present time rhTSH is approved as an adjunct for diagnostic procedures and thyroid ablation in patients with DTC. In addition, rhTSH has potential for use in facilitating the treatment of metastases in patients with DTC. In this review we have summarized our own experiences with rhTSH aided radioiodine therapy in patients with disseminated thyroid cancer. Generally, rhTSH was very well tolerated and treatment results were comparable to those achieved with thyroid hormone withdrawal.     

Delayed 131-I First Treatment After Surgery has No Impact on the Median Term Outcome of Patients with Intermediate Risk Differentiated Thyroid Cancer

Objective: In intermediate risk (IR) differentiated thyroid cancer (DTC) patients, selective use of radioiodine (131-I) for remnant ablation and/or as adjuvant therapy (RRA) is advocated. The recently suggested postoperative evaluation could delay the use of RRA. The aim of this study was to evaluate if a delayed RRA can worsen the clinical outcome of IR-DTC patients.Methods: Four hundred and fourteen consecutive IR-DTC patients were divided according to the time elapsed from surgery to RRA, <6 months (group A, 186/414 &lsqb;44.9%]), or ≥6 months (group B, 228/414 &lsqb;55.1%]). Clinical and biochemical data were collected, and clinical outcome was analyzed at the first evaluation (EV) after RRA (first-EV) and after a median of 6 years of follow-up (last-EV).Results: No difference in the clinical outcome of group A and B was found. Since a different activity of 131-I could have an impact on the outcome, we separately analyzed the groups according to the 131-I activity (low-activity group: 1,110 MBq/30 mCi &lsqb;n = 320], and high-activity group: 3,700 MBq/100 mCi &lsqb;n = 94]), further subdivided according to the time elapsed from surgery to RRA. No major differences were found in both the low- and high-activity groups when comparing the features of their subgroups A and B, as far as in their clinical outcome.Conclusion: The time elapsed between surgery and the first 131-I treatment does not influence the clinical outcome of IR-DTC patients. This finding allows a more relaxed attitude in the decision making process whether to perform the RRA in IR-DTC cases in which a selective use of 131-I is recommended.Abbreviations: ATA = American Thyroid Association; DTC = differentiated thyroid cancer; EV = evaluation; HR = high risk; 131-I = radioiodine; IR = intermediate risk; LR = low risk; rhTSH = recombinant human thyroid-stimulating hormone; RRA = radioiodine for remnant ablation; Tg = thyroglobulin; TgAb = thyroglobulin autoantibody; US = ultrasound     

The treatment of multinodular large non-toxic goiter using repeated doses of radioiodine (preliminary report)

INTRODUCTION: The aim of study was to establish the effectiveness of radioiodine therapy using 131I in the group of patients with multinodular large non-toxic goiter. MATERIAL AND METHODS: Therapy was undertaken in female patients disqualified from surgery due to high risk and these patients who didn't agree to surgery. Studies were performed in 7 women (age range: 62-82 yrs) with large goiters (2nd degree according to WHO classification and goiter volume assessed by USG over 100 cm(3)). Serum TSH, fT4, fT3, antithyroid antibodies (TPOAb, TgAb, TRAb) levels, urinary iodine concentration (UIE) were estimated in all patients parallel with radioiodine uptake test (after 5 and 24 hours), 131I thyroid scintigraphy and fine needle biopsy to exclude neoplasmatic transformation. These studies and therapy with 22 mCi 131I were repeated every 3 months. RESULTS: Before therapy median thyroid volume was approximately 145 cm(3) and during therapy gradually decreased to 76 cm(3) after 6 months and to 65 cm(3) after 12 months. Increase of TRAb can be a inhibiting factor of thyroid volume reduction. Other antithyroid antibodies showed marked tendency to rise but without significant correlation with radioiodine uptake and goiter reduction. After 12 months we found 2 patients with clinical and laboratory hypothyroidism. CONCLUSIONS: In some cases of multinodular large non-toxic goiter, the radioiodine therapy can be the best alternative way for L-thyroxine treatment or surgery therapy. The fractionated radioiodine therapy of multinodular large non-toxic goiter is safe and effective method but continuation of nodules observation is necessary.     

Application of 13-cis-retinoic acid in patients with 131I scintigraphically-negative metastases of differentiated thyroid carcinoma

INTRODUCTION: The loss of iodine uptake by differentiated thyroid carcinoma (DTC) cells is a major therapeutic problem especially in patients with nonsurgical metastatic foci or local recurrence. Using 13-cis-retinoic acid, it was attempted to retain iodine uptake as a result of redifferentiation (influence by retinoic acid receptors present in DTC cells). MATERIAL AND METHODS: Between 1999 and 2005, 13-cis-retinoic acid was used in 11 patients with disseminated PTC and high serum level of thyroglobulin (Tg) before (131)I treatment (2 patients were treated twice - 13 treatment cycles in total). Side effects in skin and mucous membranes were observed in all the patients, however, their intensity did not require termination of the therapy. RESULTS: Increase of iodine uptake was observed in 5 patients (45%). Decreased Tg concentration was observed in 9 patients. In that group, increased (131)I uptake was observed in 4 patients with distant metastases. All determinations of Tg concentrations were carried out under TSH stimulation. CONCLUSIONS: 13-cis-retinoic acid causes an increase of radioiodine uptake in around half of treated patients, however, the follow-up of these patients indicates that this increase does not result in either full remission or even stabilisation of neoplastic disease. The possibility should be considered to use cis-retinoic acid as an independent therapeutic approach in patients with radioiodine non-avid foci of thyroid carcinoma especially those showing high expression of RARb and RXRg receptors.     

The value of plasma TSH estimation and TRH stimulation test in the course of treatment of differentiated thyroid cancers.

Plasma TSH levels were measured on 114 occasions in 96 patients treated for differentiated thyroid cancer. Prior to thyroid surgery, plasma TSH levels were within the range of normal. Plasma TSH levels increased slightly following partial thyroid resection and definitely after total thyroid ablation. In patients where the removal of normal thyroid induced hormonogenesis in thyroid tumours, plasma TSH levels were dependent on the hormonal secretion of the tumour as shown by inverse relationship between TSH and both PBI and 131I uptake. The increase of radioiodide uptake following stimulation by exogenous bovine TSH was inversely related to the plasma thyrotropin levels. The suppressibility of enhanced thyrotropin levels was complete with individually adjusted doses of synthetic thyroid hormones. With the exception of patients on suppressive treatment, TRH administration induced increase in plasma TSH levels. The findings are discussed with regard to the role played by TSH in the induction of hormonogenesis in thyroid tumours. The practical values of TSH estimation and TRH stimulation seem to be low; the measurements of thyrotropin levels may be important for the estimation of the suppressive effect in the course of and following withdrawal of treatment with thyroid hormones.     

Utilisation de la thyreostimuline humaine recombinante dans la préparation au traitement par iode-131 des pathologies thyroïdiennes

The introduction of recombinant human TSH (rhTSH) as a method of preparation for radioiodine therapy of follicular-derivated thyroid tumors (benign and malignant) is a significant medical advance. RhTSH has been approved for use in remnants ablation after total thyroidectomy for carcinoma. There are other potential uses for rhTSH that have not yet been licensed. The use of rhTSH allows to reduce administrated doses in goiters through an increase of iodine uptake and a more homogeneous distribution of radioiodine in the gland. RhTSH also improves thyroid cancer patients’quality of life by avoiding hypothyroidism.     

Potassium iodide (KI) to block the thyroid from exposure to I-131: current questions and answers to be discussed

Thyroid cancer in children and adolescents has to be considered as the most severe health consequence of a nuclear reactor emergency with release of radioiodine into the atmosphere. High doses of potassium iodide are effective to block radioiodine thyroid uptake and to prevent development of thyroid cancer years later. However, there are controversies concerning thyroid cancer risk induced by radioiodine exposure in adults. Further, the interaction of nutritional supply of potassium iodide and radioiodine uptake as well as the interaction of radioiodine with certain drugs has not been addressed properly in existing guidelines and recommendations. How to proceed in case of repeated release of radioiodine is an open, very important question which came up again recently during the Fukushima accident. Lastly, the side effects of iodine thyroid blocking and alternatives of this procedure have not been addressed systematically up to now in guidelines and recommendations. These questions can be answered as follows: in adults, the risk to develop thyroid cancer is negligible. In countries, where nutritional iodine deficiency is still an issue, the risk to develop thyroid cancer after a nuclear reactor emergency has to be considered higher because the thyroid takes up more radioiodine as in the replete condition. Similarly, in patients suffering from thyrotoxicosis, hypothyroidism or endemic goitre not being adequately treated radioiodine uptake is higher than in healthy people. In case of repeated or continued radioiodine release, more than one dose of potassium iodide may be necessary and be taken up to 1 week. Repeated iodine thyroid blocking obviously is not harmful. Side effects of iodine thyroid blocking should not be overestimated; there is little evidence for adverse effects in adults. Newborns and babies, however, may be more sensitive to side effects. In the rare case of iodine hypersensitivity, potassium perchlorate may be applied as an alternative to iodine for thyroid blocking.     

Radioiodine Remnant Ablation: Current Indications and Dosing Regimens

ObjectiveTo review and comment on current indica tions for radioiodine remnant ablation (RRA) in patients with differentiated thyroid cancer.MethodsThe stratification of patients as potential candidates for RRA, the benefits and risks of RRA, and the optimal preparation and administered doses of iodine 131 for RRA are discussed.ResultsWhen RRA for patients with low and inter mediate-risk differentiated thyroid cancer is being consid ered, the benefits—including survival, influence on mor bidity and recurrence, and ease of monitoring—should be weighed against the potential risks. RRA should have limited use in many low-risk patients, particularly those with stage I disease who are young and have small pri mary tumors, no lymph node involvement, and no extrano dal invasion. Measurement of serum thyroglobulin 6 to 8 weeks after thyroidectomy during levothyroxine suppres sion can be used for further stratification of risk in these patients. RRA should be used only selectively in low to intermediate-risk patients and reserved primarily for older patients with large tumors, extensive lymph node involve ment, and high-risk (tall cell, insular) subtypes of differ entiated thyroid cancer. Most low-risk to intermediate-risk patients who do warrant RRA can be prepared with recom binant human thyroid-stimulating hormone and given the smallest dose possible (30 to 50 mCi of iodine 131) for successful remnant ablation. Single-photon emission com puted tomography-computed tomographic imaging and dosimetry are new tools that can help in the management of many patients with thyroid cancer.ConclusionAlthough a large database study has shown a trend of increased use of RRA after thyroidectomy between 1990 and 2008 in the United States, recent studies and guidelines suggest a more limited use in patients with low-risk disease, which may change this trend. (Endocr Pract. 2012;18:604-610)     

Influence of the endogene TSH stimulation of thyroid volume increase in the patients after total thyroidectomy due to differentiated thyroid cancer

INTRODUCTION: The treatment-of-choice for differentiated thyroid carcinoma (DTC) is a total thyroidectomy with subsequent radioiodine therapy. In order to increase an iodine uptake in thyroid tissue remnants, the L-thyroxine withdrawal is required. It is recommended to achieve TSH levels higher than 25 mU/ml. As TSH is a known key factor in thyroid cell proliferation regulation, prolonged stimulation of the cells during L-thyroxine withdrawal can be a causative factor for a re-growth. Our aim was to assess the degree of thyroid re-growth in the patients after total thyroidectomy due to DTC and its possible clinical implications. MATERIAL AND METHODS: 23 patients operated due to papillary and follicular thyroid cancer were included into the study. Biochemical determinations and ultrasound thyroid imaging were performed (TSH, Tg) during suppressive L-thyroxine therapy as well as 4-5 weeks after the withdrawal. RESULTS: The mean volume of thyroid tissue remnants increased after withdrawal for substantial 30.1%. The difference was extremely significant. CONCLUSIONS: L-Thyroxine withdrawal in the patients after total thyroidectomy due to DTC can cause re-growth of the tissue remnants. The phenomenon may be of a clinical significance in the selected cases influencing therapeutic decisions.     

甲状腺结节的现代诊疗进展

绝大多数甲状腺结节都是经影像学检查无意间发现的,即使是良性甲状腺结节,也有必要进行治疗。临床医生需要综合患者的病史、体格检查及实验室、影像学或细胞学穿刺活检等检查结果尽可能明确诊断结节的良恶性。非手术微创治疗方法对于多数的良性结节行药物或放射性碘治疗如无水酒精注射(PEI)、激光光凝(ILP)、放射性碘消融(RFI)和微波消融(MWA)效果较好;而恶性或高度怀疑恶性及部分较大良性结节需行外科手术切除,根据结节的具体类型并结合各高危因素选择适当的切除范围,某些恶性结节术后还需进一步辅助碘131放射治疗并跟踪随访。本文综述了有关甲状腺结节的最新诊断和治疗进展,重点阐述了美国甲状腺协会关于甲状腺结节和分化型甲状腺癌的诊治指南的相关主张。     

碘131与他巴唑治疗甲状腺功能亢进症的临床疗效比较

目的:观察和比较碘131与他巴唑治疗甲状腺功能亢进症的临床疗效及安全性。方法:选取2012年1月至2016年1月于我院确诊并治疗的甲状腺功能亢进患者282例,根据随机数字表法分为碘131治疗组和药物治疗组,碘131治疗组采用131I进行治疗,药物治疗组采用他巴唑口服治疗。比较两组患者的临床疗效,治疗前后血清TSH(thyroid stimulating hormone,促甲状腺激素)、FT(free triiodothyronine,游离三碘甲状腺原氨酸)、FT4(free thyroxine concentration assay,血清游离甲状腺素)水平及TRAb(TRAB thyrotropin receptor antibodies,促甲状腺激素受体抗体)阳性率的变化及治疗期间不良反应的发生情况(心功能、肝功能、肾功能、甲状腺功能下降、白细胞减少),并对患者进行6个月的随访,记录和比较患者甲亢复发情况。结果:治疗后,碘131治疗组的总有效率为92.9%,显著高于药物治疗组(64.5%,P0.05);两组患者血清TSH水平较治疗前显著升高,而血清FT3、FT4水平及TRAb阳性率均较治疗前显著降低(P0.05),且碘131治疗组血清TSH水平明显高于碘131治疗组,而血清FT3、FT4水平及TRAb阳性率明显低于碘131治疗组(P0.05);碘131治疗组复发率及总不良反应发生率均明显低于药物治疗组(P0.05)。结论:碘131对甲状腺功能亢进症的疗效优于他巴唑口服治疗,可明显增加血清TSH水平,降低血清FT3、FT4水平及TRAb阳性率,且患者复发率及不良反应发生率均较低。     

Recombinant Human Thyroid-Stimulating Hormone To Stimulate 131-1 Uptake For Remnant Ablation And Adjuvant Therapy

ObjectiveTo review the current literature with regard to the use of recombinant human thyroid stimulating hormone (rhTSH) as an adjunct to radioactive iodine (RAI) remnant ablation and adjuvant therapy.MethodsLiterature review of clinical studies examining rhTSH and/or thyroid hormone withdrawal preparations for RAI remnant ablation. The primary endpoints evaluated were (1) effectiveness at ablating the thyroid bed as demonstrated by the lack of significant uptake in the thyroid bed on follow-up diagnostic imaging and (2) effectiveness in facilitating the adjuvant therapy function of RAI ablation as manifested by follow-up thyroid stimulating hormone (TSH)-stimulated serum thyroglobulin levels and clinical outcomes (recurrence rates, likelihood of having no evidence of disease at final follow-up).ResultsRAI remnant ablation can be successfully achieved using either traditional thyroid hormone withdrawal or recombinant human TSH preparation. While initial studies included primarily thyroid cancer patients at low risk of recurrence, more recent studies suggest that rhTSH can also be effectively used as preparation for RAI ablation in patients with an intermediate or high risk of recurrence. Furthermore, while early studies focused primarily on the endpoint of thyroid bed remnant ablation, more recent retrospective studies suggest that final clinical outcomes (recurrence rates, likelihood of achieving no evidence of disease status at final follow-up) over 5-10 years of follow-up are very similar with either method of preparation.ConclusionrhTSH is an effective alternative to thyroid hormone withdrawal in preparation for RAI remnant ablation in patients without evidence of distant metastases who are at low, intermediate, or high risk of recurrence.     

Highly sensitive immunoradiometric assay for TSH and thyroid radioiodine uptake as predictors of thyroid suppression test

Suppression of TSH and thyroid radioiodine uptake by doses of either T4 or T3 were compared in 33 patients in whom Graves' thyrotoxicosis had been treated with thioamide drugs and the medication was discontinued for at least 4 months. Thyroidal radiodine uptake was suppressed in 19 patients and was not suppressed in the remaining 14 patients. Basal TSH levels before suppression were 2.07 microU/ml in the former, significantly exceeding those of the latter (0.91 microU/ml). A TSH level of at least 1.2 microU/ml before suppression is a good predictor of positive thyroid radioiodine suppression with a predictive value of 76%. A level lower than 0.7 microU/ml before suppression is a good predictor of negative thyroid radioiodine uptake suppression with a predictive value of 89%. The determination of TSH levels before the thyroid suppression test was helpful in predicting the result, but there were limitations. In the thyroid suppression test positive group, circulating T4 was depressed by doses of T3. In them, the magnitude of T4 depression correlated with the levels of thyroid radioiodine uptake before suppression. The levels of TSH correlated neither to changes in T4 nor to those in thyroid radioiodine uptake. This indicates that the thyroid glands which show high radioiodine uptake are sensitive to TSH and are also sensitive to suppression. The elevated sensitivity to TSH probably warrants the disappearance of abnormal thyroid stimulation more precisely.     

Iodine 131 in the treatment of large goiters

The treatment of large, complicated goiters with iodine 131 constitutes an interesting alternative to surgery. It is minimally invasive, safe, and effective in most cases, and is particularly valuable in elderly, fragile patients with multiple co-morbidities. Also, it does not preclude the possibility of surgery, should it become a necessary alternative, for whatever reason in the future. The precise pre-treatment evaluation includes thyroid scintigraphy, calculation of thyroid volume and tracheal surface measurement. Patients who are most at risk of acute complications (very small cross sectional tracheal area, underlying respiratory pathology, and hyperthyroidism) should be managed during hospitalization for possible respiratory distress, or rhythm disturbances induced by hormone release. The choice of the iodine 131 activity depends on individual routine practice, either standardized or modulated by thyroid mass. Administration may be repeated depending on the effect obtained and the cumulative dose. Efficacy in terms of volume reduction is practically constant at an early stage. Its effectiveness is difficult to predict, often less in the case of large size goiters. It can be improved by increasing iodine fixation, for example, using synthetic antithyroid drugs. Permanent hypothyroidism is the most frequent and minor complication of the treatment. It involves biological monitoring in order to introduce hormone replacement therapy to avoid thyroid growth stimulation and negate the benefits of radioiodine treatment.     

左甲状腺素钠片联合甲状腺片用于甲状腺癌术后TSH抑制治疗的临床效果评价

摘要 目的：探究左甲状腺素钠片联合甲状腺片用于甲状腺癌术后促甲状腺激素（TSH）抑制治疗的临床效果。方法：选择2021年1月-2022年6月本院收治的甲状腺癌手术并进行碘131清甲治疗后行TSH抑制治疗的80例患者为本次研究对象,开展动态分组法,对照组及观察组,n=40。单纯左甲状腺素钠片治疗为对照组,左甲状腺素钠片联合甲状腺片治疗为观察组。比较甲状腺功能、肝肾功能、治疗效果及不良反应。结果：治疗后,游离三碘甲状腺原氨酸（FT3）、游离四碘甲状腺原氨酸（FT4）水平,观察组及对照组均较治疗前提高,但观察组低于对照组;TSH水平,两组均较治疗前降低,且观察组较对照组低（P＜0.05）;治疗前,肌酐（Scr）、谷丙转氨酶（ALT）、谷草转氨酶（AST）水平,观察组及对照组比较无差异（P＞0.05）,治疗后,各指标水平,两组均较治疗前降低,且观察组较对照组低（P＜0.05）;观察组治疗有效率高于对照组（P＜0.05）;观察组及对照组不良反应率比较无差异（P＞0.05）。结论：左甲状腺素钠片联合甲状腺片用于甲状腺癌术后TSH抑制治疗可明显改善患者甲状腺功能,提高免疫功能及治疗效果,效果优于左甲状腺素钠片单独治疗,且安全性较高。     

Thyroid activity of spontaneous hypertensive rats.

Thyroid activity of both male and female spontaneous hypertensive (SH) rats was studied by measurements of uptake and rate of release of 131-I, urinary excretion of 131-I, and thyroxine secretion rate (TSR). In addition, thyroid glands were removed at death and weighed. Radioactivity of the thyroid gland of male rats measured at intervals after administration of 131-I revealed a significantly reduced maximal uptake at 21.5 hr after injection and a reduced rate of release. The mean biological half-life of 131-I for the control group was 37.8 plus or minus 3.1 (SE) hr compared to 54.8 plus or minus 7.2 hr for hypertensives (P less than 0.05). Similar results were observed for females in that biological half-life of 131-I was 32.2 plus or minus 1.2 hr compared with 84.1 plus or minus 4.1 hr for hypertensives (P less than 0.01). Urinary excretion of 131-I by hypertensive rats at 24, 48, and 72hr after injection of 131-I did not differ from control in either experiment. Thyroid weight at autopsy was increased significantly above that of normotensive controls. TSR was measured indirectly in a third group of male spontaneously hypertensive and normotensive rats. TSR of control rats was estimated to be 0.97 mug T4/100 g body wt/day and 1.35 mug T4/100 g body wt/day for SH RATS. The results are consistent with the suggestion that the method for measurement of TSR in hypertensive rats gives an artifactually high value because TSH secretion is elevated.     

Thyroid Function in Patients Treated with Radioactive Iodine for Thyrotoxicosis

A series of 105 patients treated at least two years earlier with radioactive iodine for thyrotoxicosis have been surveyed. Eighty-five patients (81%) were euthyroid clinically and on the basis of routine thyroid function tests. Of the euthyroid patients 46 (54%) had normal thyroid-stimulating hormone (TSH) levels and 39 (46%) had raised TSH levels. There was no difference in serum triiodothyronine levels between these two groups but the serum protein bound iodine and serum thyroxine, though still well within the normal range, were significantly lower in the group with raised TSH levels. The serum cholesterol was also significantly higher in this latter group.Most of the euthyroid patients were seen again a year later. None had become hypothyroid and neither those with normal nor those with raised TSH levels showed any evidence of a decline in the level of serum thyroxine.It is concluded that raised serum TSH levels in patients treated with iodine-131 are not necessarily indicative of hypothyroidism. There is no indication that patients who have this abnormality become overtly hypothyroid over a 12-month follow up.     

Long-term carbimazole treatment of neonatal nonautoimmune hyperthyroidism due to a new activating TSH receptor gene mutation (Ala428Val)

BACKGROUND: Hereditary nonautoimmune hyperthyroidism is caused by activating germline mutations in the thyrotropin receptor gene. Antithyroid treatment failed to control hyperthyroidism in most cases, so that primary thyroid ablation or 131I therapy is advocated as the preferred treatment of choice. PATIENT/METHODS: We describe a case of neonatal nonautoimmune hyperthyroidism treated with carbimazole. Molecular analysis revealed a new heterozygous point mutation (A428V) in the TSH receptor (TSHR) gene. RESULT: Antithyroid treatment was successful in controlling hyperthyroidism for the first 5.9 years of age. CONCLUSION: We conclude that carbimazole therapy is effective in treating nonautoimmune hyperthyroidism. It may be an alternative to thyroidectomy or radioiodine treatment.     

The use of radioactive iodine in the treatment of Graves disease

Fifty patients with uncomplicated Graves' disease were treated with radioactive iodine (I(131)). Twenty-six patients who were followed for one year or longer are the basis of this report. Twenty-five are now euthyroid; only one is not completely well. The total dose of radioiodine administered varied from 0.5 to 10 millicuries. The average length of time necessary for return to a euthyroid state was from three to four months. Hypometabolism developed in three patients, and in one the signs and symptoms of myxedema developed. No other complications ensued. One patient who apparently relapsed had complete return to normal after further iodine administration. The determination of the uptake of radioactive iodine by the thyroid gland is a useful diagnostic procedure in differentiating conditions simulating hyperthyroidism.Following treatment with radioactive iodine, the thyroid gland becomes smaller, the uptake of iodine by the gland is reduced, and the level of organic iodine in the plasma becomes normal. In acute thyroiditis, in spite of a high basal metabolic rate, high content of organic iodine in the plasma and other evidences of "hyperthyroidism," the uptake of I(131) has been very low.