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The Quarterly Journal of Nuclear... Jun 2022Nuclear medicine methods were introduced in the 1940s for thyroid disease diagnosis and therapy. They is still a crucial part of thyroid nodules work-up. Thyroid imaging... (Meta-Analysis)
Meta-Analysis
Nuclear medicine methods were introduced in the 1940s for thyroid disease diagnosis and therapy. They is still a crucial part of thyroid nodules work-up. Thyroid imaging with iodine or iodine-analog isotopes is widely employed in patients with thyrotoxicosis and remains the only examination able to prove the presence of autonomously functioning thyroid tissue, which excludes malignancy with a high probability. In addition, technetium-99m-methoxyisobutylisonitrile ([Tc]Tc-MIBI) scintigraphy and positron emission tomography/computed tomography (PET/CT) with F-fluoro-2-deoxy-d-glucose ([F]FDG) are able to avoid unnecessary surgical procedures for cytologically inconclusive thyroid nodules, as confirmed by meta-analysis and cost-effectiveness studies. All considered thyroid molecular imaging allows functional characterization of different thyroid diseases, even before clinical symptoms become manifest, and remains integral to the management of such conditions. This paper summarizes main concepts of thyroid scintigraphy and its clinical use. In addition, it elaborates development of thyroid scintigraphy, as well as thyroid molecular imaging in patients with thyroid nodules and thyrotoxicosis.
Topics: Fluorodeoxyglucose F18; Humans; Iodine; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Thyroid Neoplasms; Thyroid Nodule; Thyrotoxicosis
PubMed: 35166094
DOI: 10.23736/S1824-4785.22.03428-8 -
Endocrine Dec 2017Testis was considered unresponsive to thyroid hormone for a long time. However, like in animals, the presence of thyroid hormone receptors in different testicular cell... (Review)
Review
INTRODUCTION
Testis was considered unresponsive to thyroid hormone for a long time. However, like in animals, the presence of thyroid hormone receptors in different testicular cell types was demonstrated also in humans. Accordingly, thyrotoxicosis and hypothyroidism have remarkable effects on testicular function and more extensively on fertility.
REVIEW
Thyrotoxicosis and hypothyroidism are associated with changes affecting the endocrine, sexual, or reproductive functions. Particularly, compared with controls, hyperthyroid patients have higher serum SHBG and lower free and bioavailable testosterone concentrations, a higher rate of astheno-zoospermia, oligo-zoospermia, and terato-zoospermia, and a higher prevalence of sexual disturbances, such as premature ejaculation. In hypothyroid patients, hormonal changes are in the opposite direction compared with hyperthyroid patients. Thyroid hormone regulates a number of functions in the testis, such as proliferation and differentiations of non-germ cells, steroidogenesis, and sperm motility. Furthermore, thyroid hormone regulates testicular redox status. Consequently, thyroid hormone excess or deficiency can affect testicular function at different levels.
CONCLUSIONS
In view of the high prevalence of thyrotoxicosis and hypothyroidism, a considerable part of infertile patients may harbor overt or subclinical thyroid disease. Identification and management of thyrotoxicosis/hypothyroidism associated infertility needs the collaboration of andrologists, endocrinologists, gynecologists, and general practitioners.
Topics: Humans; Hyperthyroidism; Hypothyroidism; Infertility, Male; Male; Testicular Diseases; Testis; Thyroid Diseases; Thyrotoxicosis
PubMed: 28429281
DOI: 10.1007/s12020-017-1303-8 -
Endocrine Dec 2022This study aims to review all published cases on the association between thyrotoxicosis and Takutsubo Syndrome by describing clinical characteristics, diagnostic... (Review)
Review
PURPOSE
This study aims to review all published cases on the association between thyrotoxicosis and Takutsubo Syndrome by describing clinical characteristics, diagnostic work-up, treatment, and outcome.
METHODS
We searched PubMed and Embase databases from inception to the 17th of February 2022 for case reports or series reporting the above-mentioned association. We extracted data on demographic characteristics, clinical features, diagnostic work-up, treatment, and clinical outcomes. Cases were stratified into groups based on the presumed cause of the thyrotoxicosis (iatrogenic vs non-iatrogenic and Graves' diseases vs non-Graves' disease, respectively).
RESULTS
We identified 25 cases from 24 articles. The mean age was 61.7 years (+/- SD 14.5). Most patients were women (88%). Graves' disease (52%) was the leading cause of thyrotoxicosis. Previous cancer was significantly more common in patients with iatrogenic thyrotoxicosis (P = 0.03). The most common symptoms were respiratory symptoms (68%), chest pain (56%), and palpitations (40%). The most common ECG characteristics were T-wave abnormalities (48%) and ST-elevations (36%). Elevated troponin levels were found in 92% of the cases. Patients with Graves's disease and Takutsubo Syndrome had higher plasma levels of serum thyroxine (P = 0.03) and were more often treated with beta-blockers (P = 0.01) compared to patients with thyrotoxicosis of other origins. Notably, 40% of cases experienced in-hospital complications. No deaths were reported. All patients had improved cardiac function within a median follow-up of 42 days.
CONCLUSION
Evidence-based on current case reports suggests an increased risk of Takutsubo Syndrome and subsequently increased risk of in-hospital complications in patients with thyrotoxicosis.
Topics: Humans; Female; Middle Aged; Male; Takotsubo Cardiomyopathy; Thyrotoxicosis; Graves Disease
PubMed: 36018537
DOI: 10.1007/s12020-022-03174-w -
The Journal of Applied Laboratory... Sep 2023Free triiodothyronine (fT3) testing is most useful when thyroid stimulating hormone (TSH) is suppressed, and free thyroxine (fT4) is normal or decreased. These...
BACKGROUND
Free triiodothyronine (fT3) testing is most useful when thyroid stimulating hormone (TSH) is suppressed, and free thyroxine (fT4) is normal or decreased. These laboratory values in a symptomatic patient are referred to as T3 thyrotoxicosis. Standards for fT3 reflex testing have not been established. Herein, we examined the clinical utility of fT3 with the goal of identifying a TSH cutoff in the context of normal/decreased fT4 that maximizes the utility of measuring fT3.
METHODS
TSH, fT4, and fT3 results between January 2016 and October 2021 were extracted from the laboratory information system and grouped if resulted on the same day for the same patient. Frequency of biochemical T3 thyrotoxicosis was evaluated at different TSH cutoffs and in outpatient vs inpatient settings.
RESULTS
Of the 4366 TSH-fT4-fT3 results, 70 (1.6%) were consistent with biochemical T3 thyrotoxicosis. The common reasons were previously diagnosed hyperthyroidism on antithyroid medication (n = 28) or hypothyroidism on thyroid medication (n = 18) and newly diagnosed hyperthyroidism (n = 20, 0.5%). The likelihood of detecting T3 thyrotoxicosis increased with lower TSH cutoff (<0.3 μIU/mL, 10.3% vs <0.0 1μIU/mL, 27.6%). All patients with newly diagnosed hyperthyroidism had TSH <0.01 μIU/mL. Higher frequency of T3 thyrotoxicosis was observed in the outpatient setting (34%) relative to the inpatient setting (14%, P < 0.001) when TSH < 0.01 μIU/mL.
CONCLUSIONS
T3 thyrotoxicosis is a relatively rare diagnosis and fT3 measurement has limited utility in the vast majority of patients. A fT3 reflex for patients with TSH <0.01 μIU/mL and normal/low fT4 may improve clinical utility and reduce unnecessary testing, especially in the outpatient setting.
Topics: Humans; Triiodothyronine; Thyroxine; Hyperthyroidism; Thyrotropin; Thyrotoxicosis
PubMed: 37473430
DOI: 10.1093/jalm/jfad032 -
Journal of Intensive Care Medicine May 2015Amiodarone is an effective medication for the treatment of cardiac arrhythmias. Originally developed for the treatment of angina, it is now the most frequently... (Review)
Review
Amiodarone is an effective medication for the treatment of cardiac arrhythmias. Originally developed for the treatment of angina, it is now the most frequently prescribed antiarrhythmia drug despite the fact that its use is limited because of potential serious side effects including adverse effects on the thyroid gland and thyroid hormones. Although the mechanisms of action of amiodarone on the thyroid gland and thyroid hormone metabolism are poorly understood, the structural similarity of amiodarone to thyroid hormones, including the presence of iodine moieties on the inner benzene ring, may play a role in causing thyroid dysfunction. Amiodarone-induced thyroid dysfunction includes amiodarone-induced thyrotoxicosis (AIT) and amiodarone-induced hypothyroidism (AIH). The AIT develops more commonly in iodine-deficient areas and AIH in iodine-sufficient areas. The AIT type 1 usually occurs in patients with known or previously undiagnosed thyroid dysfunction or goiter. The AIT type 2 usually occurs in normal thyroid glands and results in destruction of thyroid tissue caused by thyroiditis. This is the result of an intrinsic drug effect from the amiodarone itself. Mixed types are not uncommon. Patients with cardiac disease receiving amiodarone treatment should be monitored for signs of thyroid dysfunction, which often manifest as a reappearance of the underlying cardiac disease state. When monitoring patients, initial tests should include the full battery of thyroid function tests, thyroid-stimulating hormone, thyroxine, triiodothyronine, and antithyroid antibodies. Mixed types of AIT can be challenging both to diagnose and treat and therapy differs depending on the type of AIT. Treatment can include thionamides and/or glucocorticoids. The AIH responds favorably to thyroid hormone replacement therapy. Amiodarone is lipophilic and has a long half-life in the body. Therefore, stopping the amiodarone therapy usually has little short-term benefit.
Topics: Amiodarone; Anti-Arrhythmia Agents; Female; Humans; Hypothyroidism; Male; Middle Aged; Thyroid Function Tests; Thyroid Gland; Thyrotoxicosis
PubMed: 24067547
DOI: 10.1177/0885066613503278 -
BMC Endocrine Disorders Jun 2021Thyrotoxicosis is the state of thyroid hormone excess. But, in sub-Saharan Africa (SSA), specifically Northern Ethiopia, scientific evidence about thyrotoxicosis and its...
BACKGROUND
Thyrotoxicosis is the state of thyroid hormone excess. But, in sub-Saharan Africa (SSA), specifically Northern Ethiopia, scientific evidence about thyrotoxicosis and its cardiac complications like dilated cardiomyopathy is limited. Therefore, this study aimed to explore the thyrotoxicosis presentation and management and identify factors associated with dilated cardiomyopathy in a tertiary hospital in Northern Ethiopia.
METHODS
An institution-based cross-sectional study was conducted in Ayder Comprehensive Specialized Hospital from 2017 to 2018. Data from 200 thyrotoxicosis cases were collected using a structured questionnaire. After describing variables, logistic regression was conducted to identify independent predictors of dilated cardiomyopathy. Statistical significance was declared at p < 0.05.
RESULTS
Mean age at presentation of thyrotoxicosis was 45 years and females accounted for 89 % of the cases. The most frequent etiology was multinodular toxic goiter (51.5 %). As well, the most common symptoms and signs were palpitation and goiter respectively. Thyroid storm occurred in 6 % of the cases. Out of 89 patients subjected to echocardiography, 35 (39.3 %) of them had dilated cardiomyopathy. And, the odds of dilated cardiomyopathy were higher in patients who had atrial fibrillation (AOR = 15.95, 95 % CI:5.89-38.16, p = 0.001) and tachycardia (AOR = 2.73, 95 % CI:1.04-7.15, p = 0.040). All patients took propylthiouracil and 13.0 % of them experienced its side effects. Concerning β-blockers, propranolol was the most commonly (78.5 % of the cases) used drug followed by atenolol (15.0 %). Six patients underwent surgery.
CONCLUSIONS
In developing countries like Ethiopia, patients with thyrotoxicosis have no access to methimazole which is the first-line anti-thyroid drug. Besides, they greatly suffer from dilated cardiomyopathy (due to late presentation) and side effects of propylthiouracil. Therefore, we recommend that patients should get adequate health information about thyrotoxicosis and anti-thyroid drugs including their side effects. Additionally, hospitals and other concerned bodies should also avail of TSH tests and methimazole at an affordable cost. Furthermore, community awareness about iodized salt and iodine-rich foods should be enhanced.
Topics: Adolescent; Adult; Antithyroid Agents; Cardiomyopathy, Dilated; Cross-Sectional Studies; Developing Countries; Ethiopia; Female; Goiter, Nodular; Humans; Iodine; Male; Methimazole; Middle Aged; Sodium Chloride, Dietary; Thyrotoxicosis; Young Adult
PubMed: 34182968
DOI: 10.1186/s12902-021-00796-5 -
Internal Medicine (Tokyo, Japan) Aug 2021Although headache attributed to hypothyroidism is coded within The International Classification of Headache Disorders, 3rd edition, an association between headache and...
Although headache attributed to hypothyroidism is coded within The International Classification of Headache Disorders, 3rd edition, an association between headache and thyrotoxicosis (hyperthyroidism) is mentioned only in the appendix. Reports on relevant cases are too scarce to establish a causal relationship. A young man with a history of migraine with aura arrived at our headache clinic with a 10-day history of headache and weight loss. Brain MRI revealed normal findings. Blood tests revealed thyrotoxicosis. A test for thyroid-related antibodies was negative. Thus, the patient was diagnosed with painless thyroiditis. The patient's headache resolved as his thyroid hormone levels decreased. To the best of our knowledge, this is the first reported case of headache exaggerated by painless thyrotoxicosis.
Topics: Headache; Humans; Hyperthyroidism; Hypothyroidism; Male; Thyroiditis; Thyrotoxicosis
PubMed: 33678752
DOI: 10.2169/internalmedicine.6975-20 -
Endocrine-related Cancer Jul 2019Thyrotoxicosis with concomitant thyroid cancer is rare and poorly recognized, which may result in delayed diagnosis, inappropriate treatment and even poor prognosis. To...
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.
Topics: Combined Modality Therapy; Diagnosis, Differential; Disease Management; Humans; Hyperthyroidism; Thyroid Neoplasms; Thyroidectomy; Thyrotoxicosis
PubMed: 31026810
DOI: 10.1530/ERC-19-0129 -
BMJ (Clinical Research Ed.) Aug 2014
Review
Topics: Adrenergic beta-Antagonists; Algorithms; Antibodies; Antithyroid Agents; Breast Feeding; Contraindications; Female; Goiter; Graves Disease; Humans; Iodine Radioisotopes; Pregnancy; Pregnancy Complications; Receptors, Thyrotropin; Referral and Consultation; Risk Factors; Thyroidectomy; Thyroiditis; Thyrotoxicosis
PubMed: 25146390
DOI: 10.1136/bmj.g5128 -
Journal of Endocrinological... Jan 2018Thyroid hormones are essential for skeletal development and are important regulators of bone maintenance in adults. Childhood hypothyroidism causes delayed skeletal... (Review)
Review
Thyroid hormones are essential for skeletal development and are important regulators of bone maintenance in adults. Childhood hypothyroidism causes delayed skeletal development, retarded linear growth and impaired bone mineral accrual. Epiphyseal dysgenesis is evidenced by classic features of stippled epiphyses on X-ray. In severe cases, post-natal growth arrest results in a complex skeletal dysplasia. Thyroid hormone replacement stimulates catch-up growth and bone maturation, but recovery may be incomplete dependent on the duration and severity of hypothyroidism prior to treatment. A severe phenotype characteristic of hypothyroidism occurs in children with resistance to thyroid hormone due to mutations affecting THRA encoding thyroid hormone receptor α (TRα). Discovery of this rare condition recapitulated animal studies demonstrating that TRα mediates thyroid hormone action in the skeleton. In adults, thyrotoxicosis is well known to cause severe osteoporosis and fracture, but cases are rare because of prompt diagnosis and treatment. Recent data, however, indicate that subclinical hyperthyroidism is associated with low bone mineral density (BMD) and an increased risk of fracture. Population studies have also shown that variation in thyroid status within the reference range in post-menopausal women is associated with altered BMD and fracture risk. Thus, thyroid status at the upper end of the euthyroid reference range is associated with low BMD and increased risk of osteoporotic fragility fracture. Overall, extensive data demonstrate that euthyroid status is required for normal post-natal growth and bone mineral accrual, and is fundamental for maintenance of adult bone structure and strength.
Topics: Bone and Bones; Fractures, Bone; Humans; Hypothyroidism; Mutation; Osteoporosis; Receptors, Thyroid Hormone; Thyroid Hormones; Thyrotoxicosis
PubMed: 28853052
DOI: 10.1007/s40618-017-0753-4