Thyrotoxicosis - investigation and management

Effects of Trace Elements on Endocrine Function and Pathogenesis of Thyroid Diseases-A Literature Review

The thyroid gland is an endocrine organ whose hormones enable the proper functioning of the organism. The normal function of this organ is influenced by internal and external factors. One of the external factors is trace elements. Trace elements in appropriate concentrations are necessary for the proper functioning of the thyroid. Fe, Cu, Mn, I, Zn, and Se are part of the enzymes involved in oxidative stress reduction, while Cd, Hg, and Pb can increase ROS production. Cu and Fe are necessary for the correct TPO synthesis. An imbalance in the concentration of trace elements such as Fe, Cu, Co, I, Mn, Zn, Ag, Cd, Hg, Pb, and Se in thyroid cells can lead to thyroid diseases such as Graves' disease, Hashimoto's thyroiditis, hypothyroidism, autoimmune thyroiditis, thyroid nodules, thyroid cancer, and postpartum thyroiditis. Lack of adequate Fe levels may lead to hypothyroidism and cancer development. The thyroid gland's ability to absorb I is reversibly reduced by Co. Adequate levels of I are required for correct thyroid function; both deficiency and excess can predispose to the development of thyroid disorders. High concentrations of Mn may lead to hypothyroidism. Furthermore, Mn may cause cancer development and progression. Insufficient Zn supplementation causes hypothyroidism and thyroid nodule development. Cd affecting molecular mechanisms may also lead to thyroid disorders. Hg accumulating in the thyroid may interfere with hormone secretion and stimulate cancer cell proliferation. A higher risk of thyroid nodules, cancer, autoimmune thyroiditis, and hypothyroidism were linked to elevated Pb levels. Se deficiency disrupts thyroid cell function and may lead to several thyroid disorders. On the other hand, some of the trace elements may be useful in the treatment of thyroid diseases. Therefore, the effects of trace elements on the thyroid require further research.

Thyrotoxicosis With Medullary Thyroid Carcinoma: A Rare Endocrine Diagnostic Challenge

The incidence of a hyper-functioning thyroid gland presenting alongside an underlying malignancy rarely occurs. Herein, we present a rare case of a 56-year-old female patient presenting with features of hyperthyroidism only to be later diagnosed with an underlying malignancy, medullary thyroid carcinoma (MTC). Ultrasonography (USG) of the neck revealed a suspicious nodule with microcalcifications in the right lobe of the thyroid. Subsequent CT imaging of the neck indicated possible cervical and mediastinal lymph node involvement. Fine-needle aspiration cytology (FNAC) confirmed the presence of high-grade thyroid carcinoma. The patient underwent total thyroidectomy with neck node dissection after which her symptoms subsided. She was well at her last follow-up.

Patient outcomes following thyroid surgery for thyrotoxicosis

OBJECTIVE

Total thyroidectomy can be used as a definitive treatment modality for thyrotoxicosis. This study assessed the outcomes of patients treated with surgery at a single secondary care site.

METHOD

A retrospective cohort study was conducted analysing consecutive patients who underwent thyroid surgery for thyrotoxicosis between 24 November 2000 and 26 April 2019 (n = 595).

RESULTS

Total thyroidectomy was performed in 95.4 per cent of patients. Two-thirds of patients had Graves' disease histology. Of patients, 22.8 per cent became transiently hypothyroid whilst on levothyroxine (thyroid hormone replacement therapy). Transient and persistent hypocalcaemia was present in 23.3 per cent and 2.8 per cent of patients respectively. Recurrent laryngeal nerve palsy was transient and persistent in 3.6 per cent and 0.3 per cent respectively. Of patients, 2.5 per cent developed post-operative haematomas that required surgical evacuation in the operating theatre.

CONCLUSION

The overall complication rate for thyroid surgery is higher in thyrotoxic than in euthyroid patients. Compared to other treatment modalities, total thyroidectomy appears to be the most effective, definitive means of managing Graves' disease.

A systematic review and meta-analysis of the etiology and treatment patterns of thyrotoxicosis in Africa

INTRODUCTION

Thyrotoxicosis is one of the most common endocrine disorders seen in clinical practice. This study aims to determine the etiologies and treatment modalities of thyrotoxicosis in Africa.

AREAS COVERED

The study design is a systematic review with a meta-analysis. Medical databases and the gray literature were systematically searched following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies done in Africa on the etiology and treatment of thyrotoxicosis were selected.

EXPERT OPINION

In Africa, it is still believed that autoimmune diseases, generally, are not as common as what is seen in the western world. The frequency of Graves' disease is reportedly lower in Africa. The treatment of thyrotoxicosis depends on the cause. Therefore, it is of substantial importance to establish the etiology following the diagnosis of the clinical syndrome.

Intravenous Iodinated Contrast Induced Thyrotoxic Periodic Paralysis: A Case Report

Thyrotoxic periodic paralysis (TPP) is an entity that has been described in the literature as a transient, symmetrical, flaccid paralysis, mainly affecting the lower limbs of patients with a current or previous history of hyperthyroidism. In most cases, Graves' disease is the cause of hyperthyroidism. Contrast and iodine-induced TPP have been described in the literature, but only one case of intravenous contrast induced TPP has been reported. We report a case of TPP following administration of intravenous contrast for a computed tomography scan of the neck prior to lymph node excision. A 35-year-old Kuwaiti male with known Graves' disease in remission until two months of his presentation, reported to the emergency room one early morning in December 2020. He sustained a fall from the stairs due to bilateral lower limb weakness, mostly proximal. The upper limbs were spared, and the patient did not experience any numbness or headache. His potassium was found to be 2.1 mmol/L and an electrocardiogram showed U waves and ST segment changes. He was initiated on 20 mEq of intravenous potassium chloride in 500 mL sodium chloride over one hour, following which his potassium approached normal and his weakness resolved. He was last known to be euthyroid in November 2019 but noted in October 2020 to be in the hyperthyroid state when thyroid function testing showed a thyroid-stimulating hormone of <0.005 (0.27-4.2 uIu/mL) and free thyroxine (T4) of 27.6 (7.8- pmol/L). In patients with known hyperthyroidism, more caution is required when iodine-containing substances are administered without proper evaluation of thyroid function.

Perioperative management of the thyrotoxic patients: A systematic review

Background

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

Methods

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

Conclusions

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

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

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

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Surgery and anesthesia should be postponed in elective thyrotoxicosis patients.

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

Clinical, sonographical and cytological comparison of toxic and non-toxic thyroid nodules

Aim: To compare patients with toxic and non-toxic nodular/multinodular goiter in terms of clinical, sonographical and cytological features. Material and Method: The medical data of 326 patients were reviewed retrospectively. Clinical and sonographic features were examined. Four hundred and eighty-one nodules were compared sonographically and cytologically. One hundred twenty-four patients had toxic nodular goiter and 202 of them had non-toxic nodular goiter. Results: The toxic nodular goiter group was older, they had more male sex, more multi-nodularity, larger thyroid glands and nodules with more sonographically suspicious features (p 40 mm in 13.9% of the nodules in the toxic group and 5.4% of those in the non-toxic group (p= 0.003). Central vascularization (p

Cardiovascular Involvement in Thyrotoxicosis Resulting in Heart Failure: The Risk Factors and Hemodynamic Implications

Thyrotoxicosis is a clinical syndrome with persistently elevated concentrations of free triiodothyronine, free thyroxine, or both, which correlates with an increased thyroid metabolic function. This article has discussed the direct effect of increased thyroid hormone on the heart, as the thyroid hormone physiologically exhibits a close harmony with hormones of the cardiovascular system. This action can lead to disturbances in hemodynamic stability, exacerbating the possibility of developing complications such as heart failure and life-threatening arrhythmias. This article has also explored the multifaceted pathogenesis of thyrotoxicosis and various pharmacological treatment options, including beta-blockers and anti-thyroid drugs. This article has reviewed numerous studies that have concluded that the main goal of therapy should always aim to normalize thyroid hormone levels based on the etiology of the thyrotoxicosis, although cardiovascular conditions are associated with a higher rate of mortality.

Comparative Efficacy of Haizao Yuhu Decoction Composed of Different Varieties of Glycyrrhiza in Goiter Rats

In traditional Chinese medicine, Glycyrrhiza and Sargassum are one pair of the “18 incompatible medicaments,” which in theory cannot be used together. However, since ancient times, many reports have described using compounds containing both Glycyrrhiza and Sargassum to treat diseases. Haizao Yuhu Decoction (HYD), which contains both ingredients, is mainly used to treat goiter. Chinese Pharmacopoeia officially recorded three varieties of Glycyrrhiza: Glycyrrhiza uralensis, Glycyrrhiza inflata, and Glycyrrhiza glabra. These three varieties have certain differences in chemical composition and pharmacological effects. The purpose of the present study was to investigate whether the HYD containing different varieties of Glycyrrhiza and Sargassum had different therapeutic effects in rats with goiter and to elucidate the underlying mechanism of any difference. In this study, propylthiouracil (PTU) was used to replicate the goiter model, then HYDs containing different varieties of Glycyrrhiza were used for treatment for four weeks, and then the relevant indicators were tested. The results demonstrated that HYD had antigoiter effects, alleviated the pathological changes in the thyroid tissue, and restored the abnormal serum levels of hormones related to thyroid function induced by PTU. HYD containing Glycyrrhiza uralensis had the best therapeutic effect in rats with PTU-induced goiter. The antigoiter effect of HYD may function through the hypothalamic-pituitary-thyroid (HPT) axis, inhibit the expression of the Tg and NIS genes, and regulate the synthesis of thyroid hormones, thereby reducing the excessive stimulation of TSH in thyroid cells. In addition, HYD also prevented goiter by promoting thyroid cell apoptosis and inhibiting the ERK/RSK1 pathway of cell proliferation. In conclusion, three types of HYD had different therapeutic effects in rats with goiter, which might be caused by the compatibility of different varieties of Glycyrrhiza and Sargassum.

Thyrotoxicosis with concomitant thyroid cancer

Thyrotoxicosis with concomitant thyroid cancer is rare and poorly recognized, which may result in delayed diagnosis, inappropriate treatment and even poor prognosis. To provide a comprehensive guidance for clinicians, the etiology, pathogenesis, diagnosis and treatment of this challenging setting were systematically reviewed. According to literatures available, the etiologies of thyrotoxicosis with concomitant thyroid cancer were categorized into Graves' disease with concurrent differentiated thyroid cancer (DTC) or medullary thyroid cancer, Marine-Lenhart Syndrome with coexisting DTC, Plummer's disease with concomitant DTC, amiodarone-induced thyrotoxicosis with concomitant DTC, central hyperthyroidism with coexisting DTC, hyperfunctioning metastases of DTC and others. The underlying causal mechanisms linking thyrotoxicosis and thyroid cancer were elucidated. Medical history, biochemical assessments, radioiodine uptake, anatomic and metabolic imaging and ultrasonography-guided fine-needle aspiration combined with pathological examinations were found to be critical for precise diagnosis. Surgery remains a mainstay in both tumor elimination and control of thyrotoxicosis, while anti-thyroid drugs, beta-blockers, 131I, glucocorticoids, plasmapheresis, somatostatin analogs, dopamine agonists, radiation therapy, chemotherapy and tyrosine kinase inhibitors should also be appropriately utilized as needed.

Severe cholestatic hyperbilirubinaemia secondary to thyrotoxicosis complicated with bile cast nephropathy treated with plasma exchange and haemodialysis

Thyrotoxicosis rarely presents as cholestatic hyperbilirubinaemia, and severe bilirubin elevation may lead to bile cast nephropathy. We present a case of a young woman with newly diagnosed Graves' disease with thyrotoxicosis who developed severe hyperbilirubinaemia and bile cast nephropathy. Serial plasma exchange and temporary haemodialysis led to full renal recovery. After treatment of her thyrotoxicosis with antithyroid medication and radioactive iodine ablation, her bilirubin normalised.