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Frontiers in Endocrinology 2023Published data on the relationship between polycystic ovary syndrome (PCOS) and thyroid dysfunction are sparse and confusing. (Review)
Review
BACKGROUND
Published data on the relationship between polycystic ovary syndrome (PCOS) and thyroid dysfunction are sparse and confusing.
OBJECTIVE
To comprehensively review data available in the literature regarding the relationship between PCOS and the thyroid function, and its abnormalities.
METHODS
Nine main areas of interest were identified and analyzed according to the available evidence: 1) Evaluation of thyroid function for PCOS diagnosis; 2) Epidemiology data on thyroid function/disorders in patients with PCOS, and vice versa; 3) Experimental data supporting the relationship between thyroid function/disorders and PCOS; 4) Effects of thyroid function/disorders on PCOS features, and vice versa; 5) Effect of thyroid alterations on the cardiometabolic risk in women with PCOS; 6) Effect of thyroid abnormalities on reproductive outcomes in women with PCOS; 7) Relationship between thyroid function/abnormalities in patients with PCOS who are undergoing fertility treatment; 8) Effect of treatments for thyroid diseases on PCOS; and 9) Effect of treatments for PCOS on thyroid function. An extensive literature search for specific keywords was performed for articles published from 1970 to March 2023 using PubMed and Web of Science. Data were reported in a narrative fashion.
RESULTS
PCOS is a diagnosis of exclusion for which diagnosis is possible only after excluding disorders that mimic the PCOS phenotype, including thyroid dysfunctions. However, the tests and the cutoff values used for this are not specified. Many experimental and clinical data suggest a relationship between perturbations of the thyroid function and PCOS. Direct and unequivocal evidence on the effects of thyroid function/disorders on PCOS features are lacking. High thyroid-stimulating hormone levels and subclinical hypothyroidism may be associated with significant worsening of several intermediate endpoints of cardiometabolic risk in women with PCOS. Thyroid abnormalities may worsen reproductive outcomes, especially in patients undergoing fertility treatment. To date, there are no data demonstrating the efficacy of thyroid medications on fertility and cardiometabolic risk in women with PCOS. Lifestyle modification changes, metformin, and vitamin D seem to improve thyroid function in the general population.
CONCLUSION
PCOS and thyroid disorders are closely related, and their coexistence may identify patients with a higher reproductive and metabolic risk. Regular screening for thyroid function and thyroid-specific autoantibodies in women with PCOS, particularly before and during pregnancy, is highly recommended.
Topics: Female; Humans; Pregnancy; Polycystic Ovary Syndrome; Thyroid Diseases; Hypothyroidism; Thyroid Dysgenesis; Antibodies; Cardiovascular Diseases
PubMed: 37635968
DOI: 10.3389/fendo.2023.1251866 -
Clinical Imaging Oct 2020The purpose of this study was to estimate the incidence and clinical significance of thyroid isthmus agenesis based on multi-detector CT imaging in a large-scale study.
OBJECTIVE
The purpose of this study was to estimate the incidence and clinical significance of thyroid isthmus agenesis based on multi-detector CT imaging in a large-scale study.
METHODS
Data from 1601 patients who underwent neck multi-detector CT at our institution from January 2015 to March 2016 were included in this retrospective study. The morphology of each patient's thyroid gland was evaluated. We classified thyroid isthmus agenesis into two subgroups according to the thickness of the medial margin: clear-cut type (>4 mm) or tapering-edge type (≤4 mm). Associated thyroid pathologies were also evaluated.
RESULTS
Thyroid isthmus agenesis was present in 69 patients (41 males, 28 females), and its incidence was 4.77%. Eleven patients (0.76%) had the clear-cut type and 58 patients (4.01%) had the tapering-edge type. Papillary thyroid carcinoma was diagnosed in 4 patients (5.7% of isthmus agenesis patients). A total of 7 patients underwent thyroid function testing during the course of this study; 1 of these patients presented with borderline hyperthyroidism, and the remaining 6 were in a euthyroid state. The clear-cut type showed a statistically significant narrow gap and a high incidence of pyramidal lobes compared to the tapering-edge type.
CONCLUSION
Thyroid isthmus agenesis is not a rare developmental anomaly of the thyroid gland on multi-detector CT. Based on the metastatic pathophysiology of differentiated thyroid cancer, more extended indications for lobectomy are expected in differentiated thyroid cancer patients with thyroid isthmus agenesis.
Topics: Adult; Female; Humans; Male; Middle Aged; Multidetector Computed Tomography; Retrospective Studies; Thyroid Cancer, Papillary; Thyroid Dysgenesis; Thyroid Neoplasms
PubMed: 32470707
DOI: 10.1016/j.clinimag.2020.04.038 -
Hormones (Athens, Greece) Jun 2021Congenital primary hypothyroidism (CH) is a state of inadequate thyroid hormone production detected at birth, caused either by absent, underdeveloped or ectopic thyroid... (Review)
Review
PURPOSE
Congenital primary hypothyroidism (CH) is a state of inadequate thyroid hormone production detected at birth, caused either by absent, underdeveloped or ectopic thyroid gland (dysgenesis), or by defected thyroid hormone biosynthesis (dyshormonogenesis). A genetic component has been identified in many cases of CH. This review summarizes the clinical and biochemical features of the genetic causes of primary CH.
METHODS
A literature review was conducted of gene defects causing congenital hypothyroidism.
RESULTS
Mutations in five genes have predominantly been implicated in thyroid dysgenesis (TSHR, FOXE1, NKX2-1, PAX8, and NKX2-5), the primary cause of CH (85%), and mutations in seven genes in thyroid dyshormonogenesis (SLC5A5, TPO, DUOX2, DUOXA2, SLC6A4, Tg, and DEHAL1). These genes encode for proteins that regulate genes expressed during the differentiation of the thyroid, such as TPO and Tg genes, or genes that regulate iodide organification, thyroglobulin synthesis, iodide transport, and iodotyrosine deiodination. Besides thyroid dysgenesis and dyshormonogenesis, additional causes of congenital hypothyroidism, such as iodothyronine transporter defects and resistance to thyroid hormones, have also been associated with genetic mutations.
CONCLUSION
The identification of the underlying genetic defects of CH is important for genetic counseling of families with an affected member, for identifying additional clinical characteristics or the risk for thyroid neoplasia and for diagnostic and management purposes.
Topics: Congenital Hypothyroidism; Dual Oxidases; Forkhead Transcription Factors; Humans; Infant, Newborn; Iodides; Mutation; Serotonin Plasma Membrane Transport Proteins; Thyroid Dysgenesis; Thyroid Hormones
PubMed: 33400193
DOI: 10.1007/s42000-020-00267-x -
Clinics in Perinatology Mar 2018Congenital hypothyroidism is common and can cause severe neurodevelopmental morbidity. Prompt diagnosis and treatment are critical to optimizing long-term outcomes.... (Review)
Review
Congenital hypothyroidism is common and can cause severe neurodevelopmental morbidity. Prompt diagnosis and treatment are critical to optimizing long-term outcomes. Universal newborn screening is an important tool for detecting congenital hypothyroidism, but awareness of its limitations, repeated screening in high-risk infants, and a high index of clinical suspicion are needed to ensure that all affected infants are appropriately identified and treated. Careful evaluation will usually reveal the etiology of congenital hypothyroidism, which may inform treatment and prognosis. Early and adequate treatment with levothyroxine results in excellent neurodevelopmental outcomes for most patients with congenital hypothyroidism.
Topics: Congenital Hypothyroidism; Deficiency Diseases; Disease; Early Diagnosis; Early Medical Intervention; Hormone Replacement Therapy; Humans; Infant, Newborn; Iodine; Neonatal Screening; Prognosis; Thyroid Dysgenesis; Thyroid Gland; Thyroxine
PubMed: 29405999
DOI: 10.1016/j.clp.2017.10.004 -
QJM : Monthly Journal of the... Jul 2023
Topics: Humans; Thyroid Dysgenesis; Ultrasonography
PubMed: 37021964
DOI: 10.1093/qjmed/hcad054 -
Frontiers in Endocrinology 2022Preterm newborns are forced to adapt to harsh extrauterine conditions and endure numerous adversities despite their incomplete growth and maturity. The inadequate... (Review)
Review
Preterm newborns are forced to adapt to harsh extrauterine conditions and endure numerous adversities despite their incomplete growth and maturity. The inadequate thyroid hormones secretion as well as the impaired regulation of hypothalamus-pituitary-thyroid axis may lead to hypothyroxinemia. Two first weeks after birth are pivotal for brain neurons development, synaptogenesis and gliogenesis. The decreased level of thyroxine regardless of cause may lead to delayed mental development. Congenital hypothyroidism (CH) is a disorder highly prevalent in premature neonates and it originates from maternal factors, perinatal and labor complications, genetic abnormalities, thyroid malformations as well as side effects of medications and therapeutic actions. Because of that, the prevention is not fully attainable. CH manifests clinically in a few distinctive forms: primary, permanent or transient, and secondary. Their etiologies and implications bear little resemblance. Therefore, the exact diagnosis and differentiation between the subtypes of CH are crucial in order to plan an effective treatment. Hypothyroxinemia of prematurity indicates dynamic changes in thyroid hormone levels dependent on neonatal postmenstrual age, which directly affects patient's maintenance and wellbeing. The basis of a successful treatment relies on an early and accurate diagnosis. Neonatal screening is a recommended method of detecting CH in preterm newborns. The preferred approach involves testing serum TSH and fT4 concentrations and assessing their levels according to the cut-off values. The possible benefits also include the evaluation of CH subtype. Nevertheless, the reference range of thyroid hormones varies all around the world and impedes the introduction of universal testing recommendations. Unification of the methodology in neonatal screening would be advantageous for prevention and management of CH. Current guidelines recommend levothyroxine treatment of CH in preterm infants only when the diagnose is confirmed. Moreover, they underline the importance of the re-evaluation among preterm born infants due to the frequency of transient forms of hypothyroidism. However, results from multiple clinical trials are mixed and depend on the newborn's gestational age at birth. Some benefits of treatment are seen especially in the preterm infants born <29 weeks' gestation. The discrepancies among trials and guidelines create an urgent need to conduct more large sample size studies that could provide further analyses and consensus. This review summarizes the current state of knowledge on congenital hypothyroidism in preterm infants. We discuss screening and treatment options and demonstrate present challenges and controversies.
Topics: Congenital Hypothyroidism; Female; Humans; Infant; Infant, Newborn; Infant, Premature; Neonatal Screening; Pregnancy; Thyroid Dysgenesis; Thyroxine
PubMed: 35370986
DOI: 10.3389/fendo.2022.860862 -
Best Practice & Research. Clinical... Mar 2017Developmental anomalies of the thyroid gland, defined as thyroid dysgenesis, underlie the majority of cases of congenital hypothyroidism. Thyroid dysgenesis is... (Review)
Review
Developmental anomalies of the thyroid gland, defined as thyroid dysgenesis, underlie the majority of cases of congenital hypothyroidism. Thyroid dysgenesis is predominantly a sporadic disorder although a reported familial enrichment, variation of incidence by ethnicity and the monogenic defects associated mainly with athyreosis or orthotopic thyroid hypoplasia, suggest a genetic contribution. Of note, the most common developmental anomaly, thyroid ectopy, remains unexplained. Ectopy may result from multiple genetic or epigenetic variants in the germline and/or at the somatic level. This review provides a brief overview of the monogenic defects in candidate genes that have been identified so far and of the syndromes which are known to be associated with thyroid dysgenesis.
Topics: Animals; Congenital Hypothyroidism; Female; Genetic Association Studies; Humans; Hypothyroidism; Incidence; Male; Morphogenesis; Thyroid Diseases; Thyroid Dysgenesis; Thyroid Gland
PubMed: 28648504
DOI: 10.1016/j.beem.2017.04.008 -
Frontiers in Endocrinology 2020Thyroid dysgenesis (TD), which is caused by gland developmental abnormalities, is the most common cause of congenital hypothyroidism (CH). In addition, advances in...
Thyroid dysgenesis (TD), which is caused by gland developmental abnormalities, is the most common cause of congenital hypothyroidism (CH). In addition, advances in diagnostic techniques have facilitated the identification of mild CH patients with a gland- (GIS) with normal thyroid morphology. Therefore, TD and GIS account for the vast majority of CH cases. Sixteen known genes to be related to CH were sequenced and screened for variations by next-generation sequencing (NGS) in a cohort of 377 CH cases, including 288 TD cases and 89 GIS cases. In our CH cohort, we found that (21.22%) was the most commonly variant pathogenic gene, while was prominent in TD (18.75%) and was prominent in GIS (34.83%). Both biallelic and triple variants of were found to be most common in children with TD and children with GIS. The most frequent combination was with among the 61 patients who carried digenic variants. We also found for the first time that biallelic , and variants participate in the pathogenesis of TD. In addition, the variant p.Y246X in was the most common variant hotspot, with 58 novel variants identified in our study. We meticulously described the types and characteristics of variants from sixteen known gene in children with TD and GIS in the Chinese population, suggesting that and variants may confer susceptibility to TD and GIS via polygenic inheritance and multiple factors, which further expands the genotype-phenotype spectrum of CH in China.
Topics: Child; China; Cohort Studies; Congenital Hypothyroidism; Dual Oxidases; Genetic Predisposition to Disease; High-Throughput Nucleotide Sequencing; Humans; Membrane Proteins; Mutation; Phenotype; Prognosis; Thyroid Dysgenesis
PubMed: 32425884
DOI: 10.3389/fendo.2020.00237 -
Medicina (Kaunas, Lithuania) Oct 2023Congenital hypothyroidism (CH) may have major detrimental effects on growth and neurological development, but early intervention leads to excellent outcomes. CH is...
Congenital hypothyroidism (CH) may have major detrimental effects on growth and neurological development, but early intervention leads to excellent outcomes. CH is classified as transient or permanent, primary or secondary, with primary CH being the most common neonatal endocrine disorder. Most patients with CH do not present any typical signs and symptoms of hypothyroidism shortly after birth, partly due to transplacental maternal thyroid hormone transfer and residual neonatal thyroid function. This paper reports on two CH cases. During the initial Neonatal Intensive Care Unit (NICU) admission phase, CH was not suspected due to nonspecific signs. The distinct characteristics of our cases are as follows: both infants were admitted to the NICU for respiratory distress syndrome, requiring invasive mechanical ventilation, and both were born to diabetic mothers. Following extubation, they both showed similar neurological issues, including reduced muscle tone and feeding difficulties. Initially, those symptoms were attributed to delayed clearance of analgesic and sedative medication. However, symptoms progressively worsened over time. Subsequent tests revealed both meeting CH diagnostic criteria: an unusual ultrasound indicating thyroid agenesis and abnormal hormone levels. Guided by the pediatric endocrinology team, prompt hormonal treatment was started with improvements in neurocognitive function and feeding. Usually, CH screening involves blood samples from healthy newborns at 2-3 days of life. Abnormal results require confirmation, prompting treatment within two weeks. Certain NICU-admitted infants face higher diagnosis delays, as seen in those two cases where CH screening was postponed. Thus, for all neonates with persistent pathologies unresponsive to standard etiological treatment, conducting a comprehensive anamnestic evaluation of the medical history, along with maternal preconceptional and prenatal nutrition, is recommended.
Topics: Infant; Pregnancy; Female; Humans; Infant, Newborn; Child; Congenital Hypothyroidism; Neonatal Screening; Thyroid Dysgenesis; Thyrotropin; Thyroxine
PubMed: 37893606
DOI: 10.3390/medicina59101887 -
Journal of the College of Physicians... Jan 2019The thyroid is an endocrine gland composed of two lateral lobes connected by a strip of thyroid tissue called an isthmus. The thyroid gland is usually associated with...
The thyroid is an endocrine gland composed of two lateral lobes connected by a strip of thyroid tissue called an isthmus. The thyroid gland is usually associated with extensive morphological variations and developmental anomalies. During the 4th intrauterine week, the thyroid gland begins to develop mainly from the invagination of the endodermal cells of the ventral floor of the primitive pharynx. One of the anomalies of the thyroid gland is the agenesis of the isthmus of the thyroid. It is a rare condition and very few cases have been reported in the literature. Another rare developmental abnormality is the presence of ectopic thyroid tissues, which are characterised by the presence of thyroid tissue in locations other than the anterolateral region of the second and fourth tracheal cartilages. Ectopic thyroid tissues are most commonly found in the lingual region but are also found in the other head/neck localisations as well. In this present case report, a 54-year-old female patient with the agenesis of the isthmus of the thyroid gland with accompanying tissues of multifocal and multicentric papillary thyroid carcinoma will be discussed. When an agenesis of the isthmus of the thyroid is detected, the agenesis of the thyroid lobes or the presence of an ectopic thyroid tissue must be considered. Especially in the patients who will undergo a thyroid surgery, it should not be forgotten that the identification of an agenesis of the isthmus as well as the other thyroid anomalies during the preoperative examination, will make a remarkable contribution in deciding the strategy of the surgery and will help in preventing the development of surgical complications. However, it is not always possible to detect the presence of these anomalies, during the preoperative examinations of the patients who will undergo thyroid surgeries; therefore, one must be careful with regard to these type of anomalies in the perioperative examinations. To the best of authors' information, the present case is considered to be the first in the literature in English, presenting with an agenesis of the isthmus of the thyroid gland in the presence of ectopic thyroid tissues associated with papillary carcinoma.
Topics: Carcinoma, Papillary; Female; Humans; Middle Aged; Thyroid Cancer, Papillary; Thyroid Dysgenesis; Thyroid Gland; Thyroid Neoplasms; Thyroidectomy; Treatment Outcome; Ultrasonography
PubMed: 30630576
DOI: 10.29271/jcpsp.2019.01.75