185 results match your criteria Euthyroid Hyperthyroxinemia

Decreased sensitivity of thyrotropin-thyroid hormone feedback control in hypothyroid and athyreotic patients treated with levothyroxine. Is serum triiodothyronine involved?

Ann Endocrinol (Paris) 2018 Apr 9;79(2):62-66. Epub 2018 Mar 9.

Department of endocrinology, Sisters of Mercy university hospital center, medical school, university of Zagreb, Zagreb, Croatia. Electronic address:

Objectives: The search for optimal therapy for hypothyroidism is challenging and complex and is still going on. We investigated TSH-thyroid hormone feedback control in hypothyroid and athyreotic patients properly treated with levothyroxine (LT4), based on normal TSH values.

Material And Methods: We randomly selected 150 hypothyroid, 110 athyreotic and 210 euthyroid subjects, determined their serum T4, T3 and TSH values and calculated T4/TSH and T3/T4 ratios. Read More

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Clinical, Genetic, and Protein Structural Aspects of Familial Dysalbuminemic Hyperthyroxinemia and Hypertriiodothyroninemia.

Front Endocrinol (Lausanne) 2017 1;8:297. Epub 2017 Nov 1.

Department of Molecular Medicine, University of Pavia, Pavia, Italy.

Familial dysalbuminemic hyperthyroxinemia (FDH-T4) and hypertriiodothyroninemia (FDH-T3) are dominantly inherited syndromes characterized by a high concentration of thyroid hormone in the blood stream. The syndromes do not cause disease, because the concentration of free hormone is normal, but affected individuals are at risk of erroneous treatment. FDH-T4 is the most common cause of euthyroid hyperthyroxinemia in Caucasian populations in which its prevalence is about 1 in 10,000 individuals, but the prevalence can be much higher in some ethnic groups. Read More

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November 2017
2 Reads


Endocr Pract 2017 Nov 17;23(11):1325-1332. Epub 2017 Aug 17.

Objective: Familial dysalbuminemic hyperthyroxinemia (FDH) is caused by abnormal human serum albumin (HSA) with an increased thyroxine (T4) affinity leading to euthyroid hyperthyroxinemia. One- and 2-step immunoassays of serum samples from FDH patients (e.g. Read More

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November 2017
5 Reads

Fetal Exposure to High Maternal Thyroid Hormone Levels Causes Central Resistance to Thyroid Hormone in Adult Humans and Mice.

J Clin Endocrinol Metab 2017 09;102(9):3234-3240

Department of Medicine, The University of Chicago, Chicago, Illinois 60637.

Context: Fetuses exposed to the high thyroid hormone (TH) levels of mothers with resistance to thyroid hormone beta (RTH-β), due to mutations in the THRB gene, have low birth weight and suppressed TSH.

Objective: Determine if such exposure to high TH levels in embryonic life has a long-term effect into adulthood.

Design: Observations in humans with a parallel design on animals to obtain a preliminary information regarding mechanism. Read More

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September 2017
5 Reads

Directional thyroid hormone distribution via the blood stream to target sites.

Mol Cell Endocrinol 2017 Dec 28;458:16-21. Epub 2017 Feb 28.

Department of Internal Medicine, Endokrinologikum Hamburg, Hamburg, Germany. Electronic address:

Thyroid hormones are bound to three major serum transport proteins, thyroxin-binding globulin (TBG), transthyretin (TTR) and human serum albumin (HSA). TBG has the strongest affinity for thyroid hormones, TTR is also found in the cerebrospinal fluid and HSA is the most abundant protein in plasma. Combination defects of either a high affinity TTR or HSA variant do not compensate TBG deficiency, underscoring the dominant role of TBG among the thyroid hormone transport proteins. Read More

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December 2017
1 Read

Diagnostic Dilemma in Discordant Thyroid Function Tests Due to Thyroid Hormone Autoantibodies.

AACE Clin Case Rep 2017 ;3(1):e22-e25

Department of Medicine, The University of Chicago, Chicago, Illinois; Department of Pediatrics and the Committee on Genetics, The University of Chicago, Chicago, Illinois.

Objective: Assay interference could be the cause of abnormal thyroid function tests. Early recognition prevents inappropriate patient management. The objective of this report is to present a case with discordant thyroid function tests in different thyroid assay platforms due to thyroid autoantibodies. Read More

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January 2017
1 Read

A case of familial dysalbuminemic hyperthyroxinemia (FDH) in Japan: FDH as a possible differential diagnosis of syndrome of inappropriate secretion of thyroid-stimulating hormone (SITSH).

Endocr J 2017 Feb 30;64(2):207-212. Epub 2016 Nov 30.

Department of Internal Medicine, Keio University School of Medicine, Tokyo 160-8582, Japan.

Familial dysalbuminemic hyperthyroxinemia (FDH) is an autosomal dominant condition and is the most commonly inherited euthyroid hyperthyroxinemia in Caucasians. However, it is extremely rare in Asian populations. A 30-year-old Japanese woman, who was incidentally found to have apparent thyroid dysfunction, was admitted to our hospital in 2004. Read More

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February 2017
8 Reads

Resistance to Thyroid Hormone Complicated with Type 2 Diabetes and Cardiomyopathy in a Patient with a TRβ Mutation.

Intern Med 2016;55(22):3295-3299. Epub 2016 Nov 15.

Department of Endocrinology and Diabetology, Hidaka General Hospital, Japan.

Resistance to thyroid hormone (RTH) is a genetic disorder characterized by reduced tissue responsiveness to thyroid hormone. We herein describe a 60-year old man who presented with the clinical features of cardiomyopathy, diabetes mellitus and elevated thyroid hormones with unsuppressed thyroid stimulating hormone. A genetic analysis of thyroid hormone receptor (TR) revealed a missense mutation (A268D) in the TRβ gene. Read More

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January 2017
1 Read

DUOX2 Gene Mutation Manifesting as Resistance to Thyrotropin Phenotype.

Thyroid 2017 01 7;27(1):129-131. Epub 2016 Dec 7.

1 Department of Medicine, The University of Chicago , Chicago, Illinois.

Resistance to thyrotropin (TSH) (RTSH; defined by elevated TSH and a normal or hypoplastic thyroid gland) can be caused by mutations in genes encoding the TSH receptor and PAX8, and it has been linked to a locus on chromosome 15. In two nonconsanguineous families with nongoitrous euthyroid hyperthyrotropinemia, typical of the RTSH phenotype, exome analysis identified five rare DUOX2 gene variants (p.A649E, p. Read More

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January 2017

Ten-year estimated risk of bone fracture in women with differentiated thyroid cancer under TSH-suppressive levothyroxine therapy.

Endokrynol Pol 2016 8;67(4):350-8. Epub 2016 Jul 8.

Endocrine Unit, Department of Internal Medicine, University of Genoa.

Introduction: After thyroidectomy and radioiodine therapy, patients with differentiated thyroid cancer (DTC) are indefinitely treated with levothyroxine (L-T4). Osteoporosis is a debated consequence of hypothyroxinaemia. The aim of this study was to evaluate bone mineral density (BMD) and fracture risk assessed by FRAX in a cohort of DTC women. Read More

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April 2017
4 Reads

Familial Dysalbuminemic Hyperthyroxinemia in a Japanese Man Caused by a Point Albumin Gene Mutation (R218P).

Jpn Clin Med 2016 4;7:9-13. Epub 2016 Apr 4.

Department of Endocrinology and Metabolism, Suifu Hospital, Mito, Japan; Division of Health Care Center, Mito Clinical Education and Training Center, Mito Kyodo General Hospital, Mito, Japan.

Familial dysalbuminemic hyperthyroxinemia (FDH) is a familial autosomal dominant disease caused by mutation in the albumin gene that produces a condition of euthyroid hyperthyroxinemia. In patients with FDH, serum-free thyroxine (FT4) and free triiodothyronine (FT3) concentrations as measured by several commercial methods are often falsely increased with normal thyrotropin (TSH). Therefore, several diagnostic steps are needed to differentiate TSH-secreting tumor or generalized resistance to thyroid hormone from FDH. Read More

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April 2016
2 Reads

Inherited defects of thyroxine-binding proteins.

Best Pract Res Clin Endocrinol Metab 2015 Oct 30;29(5):735-47. Epub 2015 Sep 30.

The University of Chicago, MC3090, 5841 South Maryland Avenue, Chicago, IL 60637, USA. Electronic address:

Thyroid hormones (TH) are bound to three major serum transport proteins, thyroxine-binding globulin (TBG), transthyretin (TTR) and human serum albumin (HSA). TBG has the strongest affinity for TH, whereas HSA is the most abundant protein in plasma. Individuals harboring genetic variations in TH transport proteins present with altered thyroid function tests, but are clinically euthyroid and do not require treatment. Read More

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October 2015
2 Reads

Familial dysalbuminaemic hyperthyroxinaemia: a rapid and novel mass spectrometry approach to diagnosis.

Ann Clin Biochem 2016 Jul 13;53(Pt 4):504-7. Epub 2015 Jul 13.

Biochemistry Department, Canterbury Health Laboratories, Christchurch, New Zealand.

Background: Familial dysalbuminaemic hyperthyroxinaemia is an important cause of discordant thyroid function test results (due to an inherited albumin variant); however, the diagnosis can be challenging. A 51-year-old man had persistently elevated free thyroxine (T4), with discordant normal thyroid-stimulating hormone and normal free triiodothyronine. He was clinically euthyroid and had a daughter with similar thyroid function test results. Read More

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July 2016
1 Read

Characteristics of patients with late manifestation of resistance thyroid hormone syndrome: a single-center experience.

Endocrine 2015 Dec 4;50(3):689-97. Epub 2015 Jun 4.

Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, 200025, People's Republic of China.

Resistance to thyroid hormone (RTH) is a rare genetic disease caused by reduced tissue sensitivity to thyroid hormone. The hallmark of RTH is elevated serum levels of thyroid hormone with unsuppressed thyrotropin (TSH). However, the most common form of RTH results from minor defects in the ligand-binding domain or hinge domain of the TRβ gene, resulting in impaired T3-induced transcriptional activity, often showing mild presentation. Read More

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December 2015
4 Reads

A case of thyroid hormone resistance: a rare mutation.

Arq Bras Endocrinol Metabol 2014 Dec;58(9):962-6

Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Portugal.

Reduced sensitivity to thyroid hormones (RSTH) is a rare disease that affects about 3,000 individuals, belonging to about 1,000 families. It results from reduced intracellular action of thyroid hormones (TH) genetically determined and manifests as persistent hyperthyroxinemia with non-suppressed thyroid-stimulating hormone (TSH). We describe a 67-years old, Caucasian woman, with past history of subtotal thyroidectomy due to diffuse goiter, who presents with a recurrence of goiter. Read More

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December 2014
3 Reads

Maternal thyroid dysfunction during gestation, preterm delivery, and birthweight. The Infancia y Medio Ambiente Cohort, Spain.

Paediatr Perinat Epidemiol 2015 Mar 7;29(2):113-22. Epub 2015 Jan 7.

Pharmacy, University Cardenal Herrera-CEU, Valencia, Spain.

Background: Maternal clinical thyroid disorders can cause reproductive complications. However, the effects of mild thyroid dysfunctions are not yet well established. The aim was to evaluate the association of maternal thyroid function during the first half of pregnancy with birthweight and preterm delivery. Read More

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March 2015
21 Reads

A family of RTHβ with p.R316C mutation presenting occasional syndrome of inappropriate secretion of TSH.

Endocr J 2015 12;62(3):251-60. Epub 2014 Dec 12.

Department of Endocrinology and Metabolism, National Hospital Organization Kyoto Medical Center, Kyoto 612-8555, Japan.

The syndrome of inappropriate secretion of thyrotropin (SITSH) is a hallmark of resistance to thyroid hormone (RTH) due to mutations in the β isoform of the thyroid hormone receptor (TRβ). Here, we report on a family of RTH due to a TRβ mutation (RTHβ) and presenting occasional SITSH. The proband was a 16 year-old girl with a goiter, detected at a school physical examination. Read More

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December 2015
1 Read

Anesthetic experience in a clinically euthyroid patient with hyperthyroxinemia and suspected impairment of T4 to T3 conversion: a case report.

Korean J Anesthesiol 2014 Aug 26;67(2):144-7. Epub 2014 Aug 26.

Department of Anesthesiology and Pain Medicine, Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwasung, Korea.

We report an anesthetic experience in a clinically euthyroid patient with hyperthyroxinemia (elevated free thyroxine, fT4 and normal 3, 5, 3'-L-triiodothyronine, T3) and suspected impairment of conversion from T4 to T3. Despite marked hyperthyroxinemia, this patient's perioperative hemodynamic profile was suspected to be the result of hypothyroidism, in reference to the presence of T4 to T3 conversion disorder. We suspected that pretreatment with antithyroid medication before surgery, surgical stress and anesthesia may have contributed to the decreased T3 level after surgery. Read More

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August 2014
4 Reads

Lithium-induced transient euthyroid hyperthyroxinemia: a case report.

Prim Care Companion CNS Disord 2014 ;16(2)

Department of Psychiatry, University of Arkansas for Medical Sciences, Little Rock.

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August 2014
1 Read

[Thyroid disease caused by receptor abnormality].

Rinsho Byori 2014 Jan;62(1):60-6

Hormone receptor abnormality is a syndrome of an abnormal mechanism caused by defective receptor function in hormone action. Resistance to thyroid hormone is a syndrome in which the responsiveness of the target organ to thyroid hormone is reduced. Resistance to thyroid hormone exhibits unsuppressed thyrotropin(TSH) despite elevated free thyroxin (FT4) and free 3,5,3'-triiodothyronine (FT3), termed the syndrome of the inappropriate secretion of TSH (SITSH). Read More

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January 2014
1 Read

A novel albumin gene mutation (R222I) in familial dysalbuminemic hyperthyroxinemia.

J Clin Endocrinol Metab 2014 Jul 19;99(7):E1381-6. Epub 2014 Mar 19.

University of Cambridge Metabolic Research Laboratories (N.S., C.M., M.A., O.R., G.L., M.G., K.C.), Wellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom; Institute of Endocrine Sciences (I.C., P.B.-P.), University of Milan, 20132 Milan, Italy; Department of Biochemistry (J.S.), University of Leicester, Leicester LE1 7RH, United Kingdom; Departments of Paediatrics (T.B.) and Clinical Chemistry (M.B.), Birmingham Childrens Hospital, Birmingham B15 2TT, United Kingdom; Departments of Endocrinology (M.D.), St Bartholomew's Hospital, London E1 4NS, United Kingdom; Department of Clinical Biochemistry (F.G.), Ealing Hospital, London UB1 3EU, United Kingdom; Department of Clinical Biochemistry (A.O., P.C.), Selly Oak Hospital, Birmingham B29 6JD, United Kingdom; and Department of Clinical Biochemistry (O.B., S.B., D.H.), Addenbrooke's Hospital, Cambridge CB2 2OO, United Kingdom.

Context: Familial dysalbuminemic hyperthyroxinemia, characterized by abnormal circulating albumin with increased T4 affinity, causes artefactual elevation of free T4 concentrations in euthyroid individuals.

Objective: Four unrelated index cases with discordant thyroid function tests in different assay platforms were investigated.

Design And Results: Laboratory biochemical assessment, radiolabeled T4 binding studies, and ALB sequencing were undertaken. Read More

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July 2014
2 Reads

Spuriously elevated free thyroxine associated with autoantibodies, a result of laboratory methodology: case report and literature review.

Endocr Pract 2014 Aug;20(8):e134-9

Department of Medicine, National University Hospital, Singapore.

Objective: We describe a case of spurious hyperthyroxinemia secondary to thyroid hormone autoantibodies (THAAbs) in a clinically euthyroid patient with Turner mosaic syndrome.

Methods: Several commonly available laboratory-based approaches were used, which indicated a disproportionate elevation of free thyroxine (T4) and ultimately led to the diagnosis of THAAbs. A literature review was undertaken to examine the clinical and laboratory associations of THAAbs. Read More

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August 2014
2 Reads

Effects of potassium iodide in concentrations of TSH, tT3 and tT4 in serum of subjects with sporotrichosis.

Mycoses 2014 Aug 18;57(8):460-5. Epub 2014 Mar 18.

Pathology Department, Regional Hospital Guillermo Diaz de la Vega of Apurimac, Peru; Clinical Pathology Service, Santa Teresa Clinic, Abancay, Peru.

The saturated potassium iodide solution (SSKI) as treatment for sporotrichosis may cause hypothyroidism by suppressing the synthesis of thyroid hormones (tT3 and tT4 ) and the iodine excess could lead to thyrotoxicosis. Evaluating the changes in serum levels of TSH, tT3 and tT4 in euthyroid patients with sporotrichosis treated with SSKI. For the selection of euthyroid patients, TSH, tT3 and tT4 concentrations were measured for those adults and children diagnosed with sporotrichosis. Read More

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August 2014
2 Reads

A novel mutation in the Albumin gene (R218S) causing familial dysalbuminemic hyperthyroxinemia in a family of Bangladeshi extraction.

Thyroid 2014 Jun 21;24(6):945-50. Epub 2014 Mar 21.

1 Department of Medicine, The University of Chicago , Chicago, llinois.

Background: Familial dysalbuminemic hyperthyroxinemia (FDH) is a common cause of euthyroid hyperthyroxinemia. Clinical recognition of FDH is crucial for preventing unnecessary therapy in clinically euthyroid patients with abnormal thyroid function tests. Our goal was to identify the cause of abnormal serum tests of thyroid function in a Canadian family of Bangladeshi extraction. Read More

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June 2014
3 Reads

Novel mutation p.A64D in the Serpina7 gene as a cause of partial thyroxine-binding globulin deficiency associated with increases affinity in transthyretin by a known p.A109T mutation in the TTR gene.

Horm Metab Res 2014 Feb 19;46(2):100-8. Epub 2013 Dec 19.

Laboratorio de Genética y Biología Molecular, Instituto de Inmunología, Genética y Metabolismo (INIGEM, CONICET-UBA), Hospital de Clínicas "José de San -Martín", C1120AAR Buenos Aires, Argentina.

Partial thyroxine-binding globulin deficiency (TBG-PD) is an endocrine defect with a prevalence of 1:4 000 in newborns. Due to the presence of a single TBG gene on the X chromosome, most familial TBG defects follow an X-linked inheritance pattern. Abnormal T4 binding to T4-binding prealbumin (TTR) is a rare cause of euthyroid hyperthyroxinemia, which is transmitted by autosomal dominant inheritance. Read More

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February 2014
1 Read

The first case of association between postpartum thyroiditis and thyroid hormone resistance in an Italian patient showing a novel p.V283A THRB mutation.

Thyroid 2013 Apr 18;23(4):506-10. Epub 2013 Mar 18.

Department of Endocrinology, Catholic University, Rome, Italy.

Background: Postpartum thyroiditis (PPT) is characterized by the development of postpartum thyroid dysfunction, which may occur up to 12 months after delivery. The syndrome usually presents with transient thyrotoxicosis, followed by transient hypothyroidism. The association of this condition with resistance to thyroid hormones (RTH) has never been described. Read More

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April 2013
3 Reads

Differentiated thyroid cancer in two patients with resistance to thyroid hormone.

Thyroid 2011 Jul 7;21(7):793-7. Epub 2011 Jun 7.

Department of Endocrinology, Catholic University School of Medicine, Rome, Italy.

Background: Resistance to thyroid hormone (RTH) is a genetic disease characterized by a reduced responsiveness of the pituitary and peripheral target tissues to TH. We describe two patients with RTH in whom differentiated thyroid cancer was diagnosed.

Patient Findings: In both patients, RTH was unequivocally diagnosed and both underwent thyroidectomy for multinodular goiter. Read More

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July 2011
1 Read

Syndromes of resistance to TSH.

Ann Endocrinol (Paris) 2011 Apr 21;72(2):60-3. Epub 2011 Apr 21.

Department of scienze Mediche, università degli Studi di Milano, Via Festa del Perdono 7, 20122 Milan, Italy.

The resistance to TSH action is a genetic disease characterized by molecular defects hampering the adequate transmission of TSH stimulatory signal into thyroid cells. In principle the defect may affect every step along the cascade of events following the binding of TSH to its receptor (TSHR) on thyroid cell membranes. The phenotypic expressivity of TSH resistance is highly variable going from severe congenital hypothyroidism (CH) with thyroid hypoplasia to mild hyperthyrotropinemia (hyperTSH) associated with an apparent euthyroid state. Read More

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April 2011
3 Reads

Three siblings with self-resolving congenital hyperthyrotropinaemia secondary to thyrotropin receptor blocking antibodies.

J Paediatr Child Health 2010 Jul 16;46(7-8):439-41. Epub 2010 Feb 16.

Paediatric Registrar, Royal Children's Hospital, Melbourne, Victoria, Australia.

Thyrotropin receptor blocking antibodies are a rare cause of hyperthyrotropinaemia and more rarely of congenital hypothyroidism. We report a case of hyperthyrotropinaemia but normal thyroid hormone in the newborn of a mother with hypothyroidism treated with thyroxine. Two older siblings had similar high thyrotropin and normal thyroid function in the newborn period which did not require hormone treatment and resolved spontaneously. Read More

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July 2010
5 Reads

Resistance to thyroid hormone in a patient with coexisting Graves' disease.

Thyroid 2010 Feb;20(2):213-6

Section of Endocrinology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756, USA.

Background: Resistance to thyroid hormone (RTH) is a rare disorder in which an abnormality in the binding domain of the thyroid hormone receptor results in end-organ insensitivity to the actions of thyroid hormones. This disorder is sometimes misdiagnosed as Graves' disease due to the presence of a goiter with high Iodine-123 thyroid uptake and high levels of total and free thyroid hormones. Additionally, some patients with RTH may experience palpitations or tachycardia. Read More

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February 2010
5 Reads

Impact of resistance to thyroid hormone on the cardiovascular system in adults.

J Clin Endocrinol Metab 2009 Aug 12;94(8):2812-6. Epub 2009 May 12.

Department of Clinical and Molecular Endocrinology and Oncology, University Federico II of Naples, Via S. Pansini 5, Naples, Italy.

Background: The clinical manifestations of resistance to thyroid hormone (RTH) are highly variable, and the impact of RTH on the cardiovascular system has been poorly investigated.

Aim: The objective of the study was to evaluate the cardiovascular characteristics of 16 untreated and asymptomatic patients with RTH compared with 16 euthyroid healthy controls to define the cardiovascular involvement in RTH syndrome.

Patients And Methods: Sixteen untreated and asymptomatic RTH patients (eight males; aged 33 +/- 12 yr, range 21-45 yr) and 16 controls (nine males; aged 33 +/- 5 yr, range 24-42 yr) were enrolled. Read More

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August 2009
2 Reads

Augmentation index in resistance to thyroid hormone (RTH).

Clin Endocrinol (Oxf) 2009 Apr 17;70(4):650-4. Epub 2008 Sep 17.

Centre for Endocrine and Diabetes Sciences, University Hospital of Wales, Cardiff, UK.

Objective: Resistance to thyroid hormone (RTH) is associated with a varied clinical presentation. The cardiac effects of RTH have been described but vascular function has yet to be fully evaluated in this condition. We have measured the arterial function of those with RTH to assess any vascular changes. Read More

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April 2009
1 Read

Clinical features and genetic analysis of four Brazilian kindreds with resistance to thyroid hormone.

Clin Endocrinol (Oxf) 2007 Nov 4;67(5):748-53. Epub 2007 Jul 4.

Division of Endocrinology, Department of Internal Medicine, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.

Objective: Resistance to thyroid hormone (RTH) is a dominantly inherited syndrome of reduced tissue responsiveness to thyroid hormone usually due to mutations located in the ligand-binding domain and adjacent hinge region of the thyroid hormone receptor beta (TRbeta). In the present report we describe the clinical and laboratory characteristics and the genetic analysis of patients with this rare disorder from a Brazilian population.

Patients: Four unrelated Brazilian families with diagnosis of RTH were studied. Read More

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November 2007
1 Read

Thyroid hormone resistance without mutations in thyroid hormone receptor beta.

Med Sci Monit 2007 Jun;13(6):CS67-70

Division of Endocrinology and Nephrology, University of Leipzig, Leipzig, Germany.

Background: Resistance to thyroid hormone (RTH) is a rare autosomal dominant disorder that leads to elevated free thyroid hormone levels in the presence of normal or increased serum thyroid-stimulating hormone (TSH) concentrations if it is generalized because both the pituitary and peripheral tissues are then partially resistant. In approximately 85% of patients with RTH, mutations in the thyroid hormone receptor beta (TR beta) gene can be identified.

Case Report: A 68-year-old German man presented for surgical hernia repair. Read More

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June 2007
4 Reads

On commonness and rarity of thyroid hormone resistance: a discussion based on mechanisms of reduced sensitivity in peripheral tissues.

Med Hypotheses 2007 26;69(4):913-21. Epub 2007 Mar 26.

Lillehammer University College, 2626 Lillehammer, Norway.

Reduced sensitivity to thyroid hormone (TH) in peripheral tissues can occur as defects in TH transport into the cell, intracellular TH metabolism, cytosolic mechanisms, TH entry into the nucleus, thyroxin receptors (TRs) and receptor binding, transcription and post-transcriptional mechanisms. Current literature reveals an extensive list of mutations, drugs, toxins, metabolites and autoimmune antibodies that may impair TH action in the cell, but such impairment may not be picked up by assays of TH and TSH in blood plasma. Substances may induce tissue specific resistance to thyroid hormone (RTH), e. Read More

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October 2007
1 Read

[Euthyroid hyperthyroxinemia].

Nihon Rinsho 2006 May;Suppl 1:533-5

Department of Teratology and Genetics, Division of Molecular and Cellular Adaptation, Research Institute of Environmental Medicine, Nagoya University.

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May 2006
2 Reads

Difficulties in diagnosing and managing coexisting primary hypothyroidism and resistance to thyroid hormone.

Huy A Tran

Endocr Pract 2006 May-Jun;12(3):288-93

Department of Clinical Chemistry, Hunter Area Pathology Service, John Hunter Hospital, New South Wales, Australia.

Objective: To report a case of resistance to thyroid hormone compounded by autoimmune primary hypothyroidism and to discuss the unusual pattern of results of thyroid function tests.

Methods: A clinical case history is presented and illustrated with laboratory findings. The difficulty of monitoring the patient's response to levothyroxine supplement is also discussed, and relevant issues are addressed, including reviews of the literature. Read More

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August 2006
3 Reads

Transgenic mice expressing a human mutant beta1 thyroid receptor are hyperactive, impulsive, and inattentive.

Genes Brain Behav 2006 Apr;5(3):282-97

Program in Neuroscience, Vanderbilt University, Nashville, TN 37232-0325, USA.

Attention deficit hyperactivity disorder (ADHD) is the most commonly diagnosed childhood psychiatric disorder. We have found that a transgenic mouse bearing a human mutant thyroid receptor (TRbeta1) expresses all of the defining symptoms of ADHD--inattention, hyperactivity, and impulsivity--as well as a 'paradoxical' response to methylphenidate (MPH). As with ADHD, the behavioral phenotypes expressed by the TRbeta transgenic mice are dynamic and sensitive to changes in environmental conditions, stress, and reinforcement. Read More

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April 2006
1 Read

Resistance to thyroid hormone in a patient with thyroid dysgenesis.

Thyroid 2005 Jul;15(7):730-3

Department of Medicine, University of Chicago, Chicago, Illinois, USA.

We report a patient with the unusual coincidence of two rare congenital disorders, lingual ectopy of the thyroid gland and resistance to thyroid hormone (RTH), resulting in impaired thyroid hormone production and action, respectively. The proposita had a positive thyrotropin (TSH) newborn screening test (350 mU/L, confirmed) with normal thyroxine (T4) and no clinical signs of hypothyroidism. A scintiscan revealed lingual but no orthotopic thyroid tissue. Read More

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Autosomal dominant resistance to thyrotropin as a distinct entity in five multigenerational kindreds: clinical characterization and exclusion of candidate loci.

J Clin Endocrinol Metab 2005 Jul 3;90(7):4025-34. Epub 2005 May 3.

Department of Medicine, The University of Chicago, MC3090, 5841 South Maryland Avenue, Chicago, Illinois 60637, USA.

Context: Resistance to TSH (RTSH) is an inherited disorder of variable hyposensitivity to TSH. The metabolic consequences can range from euthyroid hyperthyrotropinemia to severe congenital hypothyroidism with thyroid hypoplasia. Although subclinical and mild hypothyroidism fitting the RTSH phenotype is common in the population, the role of genetic factors is far from being understood. Read More

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July 2005
15 Reads

Dysprealbuminemic hyperthyroxinemia in a patient with hyperthyroid graves disease.

Clin Chem 2005 Jun 15;51(6):1065-9. Epub 2005 Apr 15.

Clinical Chemistry Division, Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, MD 21287-0003, USA.

Rare mutant forms of circulating albumin and prealbumin [transthyretin (TTR)] have increased binding affinity for thyroxine (T4). Patients with these variant plasma proteins, as a result of inherited mutations or as a paraneoplastic phenomenon, typically present with increased serum total T4 and, by some assay methodologies, an increased free T4 as well. Although these individuals are, in fact, euthyroid, nonspecific symptoms may lead to inappropriate treatment for hyperthyroidism. Read More

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June 2005
1 Read

[The specific features of thyrotoxicosis and euthyroid hyperthyroxinemia developed due to the use of cordarone].

Klin Med (Mosk) 2004 ;82(12):35-9

Thyrotoxicosis (TT) is one of the thyroid (T) dysfunctions occurring with the use of cordarone. The clinical features of TT were studied in cordarone-treated patients living in Moscow and its regions (mild and moderate iodine deficiency regions). The patients were examined by using currently available procedures for measuring thyroid-stimulating hormone, free thyroxine, free triiodothyronine, antibodies to TH, TPO, interleukin-6 (IL-6), and C-reactive protein (CRP), and by employing T ultrasound study, Holter ECG monitoring. Read More

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March 2005
1 Read

[Thyroid dysfunction in long-term amiodarone administration. Correlation of the antiarrhythmic activity of amiodarone with its effect on thyroid function].

Kardiologiia 2005 ;45(1):22-7

Relationship between amiodarone-associated thyroid dysfunction and antiarrhythmic activity of amiodarone was studied in 27 patients (13 with hypothyroidism, 8 with hyperthyroidism, 6 with euthyroid hyperthyroxinemia). Amiodarone-associated hypothyroidism and euthyroid hyperthyroxinemia were not associated with loss of antiarrhythmic efficacy of amiodarone. Hypothyroidism did not require amiodarone withdrawal and therapy with L-thyroxin was conducted at the background of continued amiodarone intake. Read More

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April 2006
2 Reads

[Thyroid hormone resistance syndrome].

Arq Bras Endocrinol Metabol 2004 Feb 1;48(1):83-92. Epub 2004 Jun 1.

Serviço de Endocrinologia e Metabologia, Universidade Federal do Paraná, Curitiba, PR.

Resistance to thyroid hormone (RTH) is a syndrome characterized by elevated serum thyroid hormone (TH) levels and elevated or inappropriately normal thyrotropin levels. In general, patients exhibit TH resistance in the pituitary and peripheral tissues. The phenotype of RTH is variable; the affected individuals are clinically euthyroid or even hypothyroid depending on the severity of the mutation, the variable hyposensitivity to TH among individuals as well as in different tissues. Read More

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February 2004
1 Read

[Familial generalized thyroid hormone resistance. Report of one case].

Rev Med Chil 2004 Sep;132(9):1096-9

Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile.

Thyroid hormone resistance is a rare autosomal dominant disease associated, in more than 90% of cases, to mutations in the beta thyroid hormone receptor. We report a 23 years old male that consulted for a psychiatric condition. Clinically, the patient was euthyroid in spite of high total and free T4 and T3 concentrations, while TSH remained normal. Read More

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September 2004

Fetal loss associated with excess thyroid hormone exposure.

JAMA 2004 Aug;292(6):691-5

Endocrinology Unit, Hospital Divino Espírito Santo, Ponta Delgada, Azores-Portugal.

Context: Maternal hypothyroidism and hyperthyroidism have deleterious effects on the outcome of pregnancy. While the effects of thyroid hormone (TH) deprivation on the fetus, independently from that on the mother, can be studied in infants with congenital hypothyroidism, this is not the case in those with fetal thyrotoxicosis.

Objective: To study the effects of TH excess on fetuses carried by mothers with resistance to TH (RTH) who are euthyroid despite high TH levels but who may carry normal fetuses that are exposed to high maternal hormone levels. Read More

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August 2004
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Severe form of thyroid hormone resistance in a patient with homozygous/hemizygous mutation of T3 receptor gene.

Eur J Endocrinol 2004 Jun;150(6):819-23

Endokrinologisch-humangenetische Gemeinschaftspraxis, Bruckenstr. 21, 69120 Heidelberg, Germany.

Resistance to thyroid hormone syndrome (RTH) is a rare disorder, usually inherited as an autosomal dominant trait. Patients with RTH are usually euthyroid but can occasionally present with signs and symptoms of thyrotoxicosis or rarely with hypothyroidism. Affected individuals are usually heterozygous for mutations in the thyroid hormone receptor beta gene (TR-beta). Read More

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June 2004
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Compensatory role of thyroid hormone receptor (TR) alpha 1 in resistance to thyroid hormone: study in mice with a targeted mutation in the TR beta gene and deficient in TR alpha 1.

Mol Endocrinol 2003 Aug 15;17(8):1647-55. Epub 2003 May 15.

Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4264, USA.

Resistance to thyroid hormone (RTH) is caused by mutations of the thyroid hormone receptor beta (TR beta) gene. Almost all RTH patients are heterozygous with an autosomal dominant pattern of inheritance. That most are clinically euthyroid suggests a compensatory role of the TR alpha1 isoform in maintaining the normal functions of thyroid hormone (T3) in these patients. Read More

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August 2003
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Neonatal thyrotoxicosis and maternal infertility in thyroid hormone resistance due to a mutation in the TRbeta gene (M313T).

Clin Endocrinol (Oxf) 2002 Sep;57(3):405-9

Department of Endocrinology, St Barthoomew's and the Royal London School of Medicine and Dentistry, UK.

We report two unusual cases of resistance to thyroid hormone (RTH) in one family. The first case, a male infant, had clinical features of thyrotoxicosis in the neonatal period. In the fourth week of life weight gain was poor despite a daily intake of standard infant formula almost double the infant's estimated requirements. Read More

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September 2002

Familial dysalbuminemic hyperthyroxinemia: a rare example of albumin polymorphism and its rapid molecular diagnosis.

J Pediatr Endocrinol Metab 2002 Jun;15(6):801-7

Department of Pediatrics, The Brookdale University Hospital and Medical Center, State University of New York at Brooklyn, 11212-3198, USA.

Familial dysalbuminemic hyperthyroxinemia (FDH) is the most common cause of euthyroid hyperthyroxinemia, although a rare example of albumin polymorphism. FDH is inherited in an autosomal dominant manner and is characterized by enhanced binding of thyroxine to a mutant form of albumin, probably at Site 1, subdomain 11A. Previous laboratory tests of FDH have been cumbersome, rarely available, and required demonstration of anti-albumin precipitable T4, isoelectric focusing of serum for albumin in presence of labeled T4 and, occasionally, comparison of the concentrations of metabolites of T4 that have different binding affinities to the abnormal albumin. Read More

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June 2002
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