Nadczynność tarczycy – Etiologia i przyczyny

Nadczynność tarczycy
Etiologia i przyczyny

Nadczynność tarczycy (hipertyreoza) jest stanem charakteryzującym się nadmierną produkcją hormonów tarczycy (T4 i T3), co prowadzi do przyspieszenia metabolizmu. Najczęstszą przyczyną jest choroba Gravesa-Basedowa, stanowiąca 50-80% przypadków, o podłożu autoimmunologicznym, gdzie przeciwciała stymulujące receptor TSH (TRAb) powodują nadprodukcję hormonów. Wole toksyczne guzkowe odpowiada za 15-20% przypadków, szczególnie u osób powyżej 60. roku życia i w regionach z niedoborem jodu, wynikając z somatycznych mutacji aktywujących receptor TSH. Zapalenia tarczycy (10-12% przypadków), w tym podostre, ciche, poporodowe i indukowane lekami (np. amiodaronem), prowadzą do przejściowej nadczynności przez uwolnienie hormonów z uszkodzonych komórek. Nadmiar jodu, leki, jatrogenne przedawkowanie hormonów oraz rzadkie przyczyny, takie jak gruczolaki przysadki wydzielające TSH czy zespół oporności na hormony tarczycy, również mogą indukować hipertyreozę.

Nadczynność tarczycy – etiologia, przyczyny i czynniki wywołujące

Choroba Gravesa-Basedowa jako główna przyczyna nadczynności tarczycy
Wole guzkowe nadczynne
Zapalenia tarczycy (tyreoiditis)
Nadmierna podaż jodu
Nadmierne przyjmowanie lewotyroksyny
Inne rzadkie przyczyny nadczynności tarczycy
Czynniki ryzyka rozwoju nadczynności tarczycy

Patofizjologia nadczynności tarczycy

Patofizjologia choroby Gravesa-Basedowa
Patofizjologia autonomicznych guzków tarczycy
Mechanizm działania zapalenia tarczycy
Patomechanizm nadczynności indukowanej jodem
Inne mechanizmy nadczynności tarczycy

Epidemiologia nadczynności tarczycy
Związek czynników genetycznych i środowiskowych

Kolejne rozdziały

Nadczynność tarczycy – etiologia, przyczyny i czynniki wywołujące

Nadczynność tarczycy (hipertyreoza) to stan, w którym gruczoł tarczowy produkuje nadmierne ilości hormonów tarczycy (tyroksyny – T4 i trijodotyroniny – T3), co prowadzi do przyspieszenia metabolizmu organizmu. Schorzenie to ma złożoną etiologię, której zrozumienie jest kluczowe dla prawidłowego procesu diagnostycznego i wyboru odpowiedniego postępowania terapeutycznego.¹²

Choroba Gravesa-Basedowa jako główna przyczyna nadczynności tarczycy

Choroba Gravesa-Basedowa stanowi najczęstszą przyczynę nadczynności tarczycy, odpowiadając za około 50-80% wszystkich przypadków w krajach rozwiniętych. Jest to schorzenie o podłożu autoimmunologicznym, w którym układ odpornościowy wytwarza przeciwciała (przeciwciała stymulujące receptor TSH – TRAb), które atakują gruczoł tarczowy i stymulują go do nadmiernej produkcji hormonów.¹²³

W chorobie Gravesa-Basedowa przeciwciała naśladują działanie hormonu tyreotropowego (TSH), wiążąc się z receptorami TSH na komórkach tarczycy i pobudzając je do nadmiernej produkcji hormonów tarczycowych. Choroba występuje częściej u kobiet niż u mężczyzn (w stosunku 5:1), najczęściej między 30. a 60. rokiem życia.¹²

Dokładna przyczyna choroby Gravesa-Basedowa pozostaje nieznana, ale badania wskazują na współdziałanie czynników genetycznych i środowiskowych. Choroba ma silny komponent genetyczny – występuje rodzinnie i zwiększone ryzyko zachorowania mają osoby z dodatnim wywiadem rodzinnym w kierunku chorób autoimmunologicznych. W etiologii udowodniono rolę genów regionu HLA, CTLA4 i PTPN22, związanych z funkcją układu immunologicznego.¹²

Wole guzkowe nadczynne

Drugą najczęstszą przyczyną nadczynności tarczycy jest toksyczne wole guzkowe (wole wieloguzkowe nadczynne, choroba Plummera), które stanowi około 15-20% przypadków hipertyreozy. W tej chorobie w tarczycy powstają guzki, które autonomicznie produkują hormony tarczycowe, niezależnie od regulacji przez TSH.¹²

Wole wieloguzkowe nadczynne występuje częściej u osób starszych, szczególnie powyżej 60. roku życia i jest dominującą przyczyną nadczynności tarczycy w regionach z niedoborem jodu. Mechanizm powstawania guzków autonomicznych wiąże się z somatycznymi mutacjami aktywującymi receptory TSH, co prowadzi do niekontrolowanej produkcji hormonów tarczycy przez zmienioną tkankę.¹²

Pojedynczy nadczynny guzek tarczycy (gruczolak toksyczny, choroba Plummera) to rzadszy wariant tej samej patologii. W tym przypadku pojedynczy guzek staje się autonomiczny i produkuje nadmierne ilości hormonów tarczycowych.¹²

Zapalenia tarczycy (tyreoiditis)

Zapalenie tarczycy (tyreoiditis) jest istotną przyczyną przejściowej nadczynności tarczycy, odpowiadającą za około 10-12% przypadków. W przebiegu zapalenia dochodzi do uszkodzenia komórek pęcherzykowych tarczycy i uwolnienia zgromadzonych w gruczole hormonów tarczycowych do krwiobiegu.¹²

Rozróżniamy kilka typów zapaleń tarczycy prowadzących do nadczynności:¹²

Podostre zapalenie tarczycy (choroba de Quervaina) – najczęściej wywołane przez infekcję wirusową
Ciche (bezbólowe) zapalenie tarczycy – o podłożu autoimmunologicznym
Poporodowe zapalenie tarczycy – występujące w okresie do 12 miesięcy po porodzie
Zapalenie tarczycy indukowane lekami (np. amiodaronem)

¹²

W zapaleniach tarczycy faza nadczynności jest zwykle przejściowa i może być następnie zastąpiona przez fazę niedoczynności, zanim dojdzie do pełnego wyleczenia lub rozwoju trwałej niedoczynności.¹

Nadmierna podaż jodu

Nadmierne spożycie jodu może spowodować nadczynność tarczycy, szczególnie u osób z istniejącymi już chorobami tarczycy, takimi jak utajona choroba Gravesa-Basedowa czy wole guzkowe. Jod jest niezbędnym składnikiem do produkcji hormonów tarczycowych, jednak jego nadmiar może zaburzyć mechanizmy regulacyjne gruczołu.¹²

Nadczynność tarczycy indukowana jodem może wystąpić po ekspozycji na:¹²

Leki zawierające duże ilości jodu (np. amiodaron stosowany w zaburzeniach rytmu serca)
Środki kontrastowe zawierające jod używane w badaniach radiologicznych
Suplementy diety bogate w jod (np. preparaty z wodorostów, kelp)
Produkty spożywcze o wysokiej zawartości jodu (owoce morza, wodorosty)

¹²

Nadczynność tarczycy indukowana amiodaronem jest szczególnie trudna do leczenia, ponieważ lek ten ma długi okres półtrwania i może powodować zarówno nadczynność, jak i niedoczynność tarczycy.¹

Nadmierne przyjmowanie lewotyroksyny

Jatrogenna nadczynność tarczycy może być spowodowana przyjmowaniem zbyt dużych dawek hormonów tarczycy (lewotyroksyny) w leczeniu niedoczynności tarczycy. Sytuacja ta może wynikać z:¹²

Zbyt wysokiego dawkowania przepisanego przez lekarza
Samowolnego zwiększania dawki przez pacjenta
Zmian w metabolizmie lewotyroksyny
Interakcji z innymi lekami

¹²

W niektórych przypadkach nadczynność tarczycy może być wywołana celowym przyjmowaniem nadmiernych ilości hormonów tarczycy (tyreotoksykoza factitia).¹

Inne rzadkie przyczyny nadczynności tarczycy

Istnieją również rzadkie przyczyny nadczynności tarczycy, które obejmują:¹²

Gruczolaki przysadki wydzielające TSH – nowotwory łagodne przysadki mózgowej produkujące nadmierne ilości hormonu tyreotropowego (TSH), co stymuluje tarczycę do zwiększonej produkcji hormonów
Zespół oporności na hormony tarczycy – rzadka choroba genetyczna, w której tkanki docelowe wykazują zmniejszoną wrażliwość na hormony tarczycy
Wysokie stężenie ludzkiej gonadotropiny kosmówkowej (hCG) – może wystąpić we wczesnej ciąży, ciąży mnogiej lub ciąży zaśniadowej; hCG ma podobną strukturę do TSH i może stymulować receptory TSH
Rak tarczycy – rzadko rak pęcherzykowy tarczycy może produkować nadmierne ilości hormonów tarczycowych
Przerzutowy funkcjonalny rak tarczycy – bardzo rzadka przyczyna nadczynności
Struma ovarii – rzadki guz jajnika zawierający tkankę tarczycową, która może produkować hormony tarczycy

¹²

Czynniki ryzyka rozwoju nadczynności tarczycy

Istnieje kilka czynników, które zwiększają ryzyko rozwoju nadczynności tarczycy:¹²

Płeć żeńska – kobiety chorują od 5 do 10 razy częściej niż mężczyźni
Wiek – szczyt zachorowań na chorobę Gravesa-Basedowa przypada na 30-60 rok życia, natomiast wole guzkowe nadczynne częściej występuje u osób starszych
Obciążenie genetyczne – dodatni wywiad rodzinny w kierunku chorób tarczycy i innych chorób autoimmunologicznych zwiększa ryzyko
Palenie tytoniu – u palaczy choroba Gravesa-Basedowa występuje dwukrotnie częściej niż u osób niepalących
Ciąża i okres poporodowy – zwiększają ryzyko tyreoiditis
Przebyte infekcje wirusowe – mogą prowadzić do zapalenia tarczycy
Stres – zarówno fizyczny, jak i emocjonalny, może wpływać na reaktywność układu immunologicznego i przyczyniać się do rozwoju schorzeń autoimmunologicznych, w tym choroby Gravesa-Basedowa
Ekspozycja na promieniowanie – wcześniejsza ekspozycja regionu szyi na promieniowanie jonizujące

¹²

Patofizjologia nadczynności tarczycy

Patofizjologia nadczynności tarczycy różni się w zależności od przyczyny leżącej u jej podłoża.¹

Patofizjologia choroby Gravesa-Basedowa

W chorobie Gravesa-Basedowa układ immunologiczny wytwarza przeciwciała (immunoglobuliny stymulujące tarczycę – TSI), które wiążą się z receptorami dla TSH na komórkach tarczycy. Przeciwciała te naśladują działanie TSH, co prowadzi do:¹²

Nadmiernej stymulacji receptorów TSH
Zwiększonej syntezy i uwalniania hormonów tarczycy
Rozrostu i przerostu komórek pęcherzykowych tarczycy (wole)
Zwiększonego przepływu krwi przez tarczycę

Choroba Gravesa-Basedowa może również powodować zmiany pozatarczycowe, takie jak orbitopatia (wytrzeszcz oczu) i objawy skórne (obrzęk przedgoleniowy), które są związane z reakcją autoimmunologiczną przeciwko antygenom wspólnym dla tarczycy i tkanek oczodołu oraz skóry.¹

Patofizjologia autonomicznych guzków tarczycy

W toksycznym wolu guzkowym nadczynnym (TMNG) i gruczolaku toksycznym dochodzi do mutacji somatycznych w genach kodujących receptor TSH lub białka przekazujące sygnał wewnątrzkomórkowy. Prowadzi to do:¹²

Konstytutywnej aktywacji receptora TSH bez wiązania hormonu
Autonomicznej produkcji hormonów tarczycy niezależnie od stężenia TSH
Stopniowego wzrostu guzków i zwiększania ich aktywności hormonalnej

Wraz z wiekiem, wskutek częstych replikacji komórek klonogennych, dochodzi do somatycznych mutacji aktywujących receptory TSH, co prowadzi do powstawania guzków autonomicznych.¹

Mechanizm działania zapalenia tarczycy

W zapaleniu tarczycy dochodzi do przejściowego wzrostu stężenia hormonów tarczycowych na skutek uszkodzenia komórek pęcherzykowych i uwolnienia uprzednio zsyntetyzowanych hormonów do krwiobiegu. Zapalenie może być wywołane przez:¹²

Mechanizmy autoimmunologiczne
Infekcje wirusowe
Leki (np. amiodaron, interferon alfa)
Promieniowanie jonizujące

W przeciwieństwie do choroby Gravesa-Basedowa czy wola guzkowego nadczynnego, w zapaleniu tarczycy nie dochodzi do zwiększonej syntezy hormonów, a jedynie do ich uwolnienia z uszkodzonych komórek.¹

Patomechanizm nadczynności indukowanej jodem

Nadmiar jodu może prowadzić do nadczynności tarczycy poprzez kilka mechanizmów:¹²

Zjawisko Jod-Basedow – zwiększone stężenie jodu u osób z utajoną chorobą Gravesa-Basedowa lub autonomicznymi guzkami tarczycy prowadzi do zwiększonej produkcji hormonów
Indukcja autoimmunizacji – nadmiar jodu może prowadzić do zwiększonej produkcji autoprzeciwciał przeciwtarczycowych
Bezpośrednie uszkodzenie komórek tarczycy przez jod (np. w przypadku amiodaronu)

Nadczynność tarczycy rozwija się zwykle 2-12 tygodni po ekspozycji na nadmierną ilość jodu.¹

Inne mechanizmy nadczynności tarczycy

Inne, rzadsze mechanizmy prowadzące do nadczynności tarczycy obejmują:¹²

Nadmierna produkcja TSH – zazwyczaj spowodowana przez gruczolak przysadki wydzielający TSH
Nadmierna stymulacja przez hCG – hCG ma podobieństwo strukturalne do TSH i może aktywować receptory TSH w wysokich stężeniach
Ektopowa produkcja hormonów tarczycy – rzadko występująca w przerzutach zróżnicowanego raka tarczycy lub w struma ovarii

Epidemiologia nadczynności tarczycy

Nadczynność tarczycy jest stosunkowo częstym schorzeniem endokrynologicznym, występującym z różną częstością w różnych populacjach:¹²

Globalna częstość występowania nadczynności tarczycy wynosi 0,2-1,4% populacji
W Stanach Zjednoczonych około 1,3% populacji cierpi na nadczynność tarczycy
Częstość wzrasta do 4-5% u starszych kobiet
Nadczynność tarczycy występuje około 5-10 razy częściej u kobiet niż u mężczyzn

¹²

Choroba Gravesa-Basedowa, najczęstsza przyczyna nadczynności tarczycy, występuje głównie u młodszych kobiet i w regionach o wystarczającej podaży jodu. Z kolei toksyczne wole guzkowe jest częstsze u osób starszych i w regionach o łagodnym lub umiarkowanym niedoborze jodu.¹²

Związek czynników genetycznych i środowiskowych

Nadczynność tarczycy, szczególnie w chorobie Gravesa-Basedowa, ma złożone uwarunkowania genetyczne i środowiskowe:¹²

Czynniki genetyczne – odpowiadają za około 79% ryzyka rozwoju choroby Gravesa-Basedowa; zidentyfikowano kilka genów związanych z podatnością na chorobę, w tym geny regionu HLA, CTLA4 i PTPN22
Czynniki środowiskowe – stanowią około 21% ryzyka i obejmują palenie tytoniu, stres, infekcje, ciążę oraz ekspozycję na substancje zaburzające funkcję tarczycy

¹²

Interakcja między predyspozycją genetyczną a czynnikami środowiskowymi prowadzi do utraty tolerancji immunologicznej i rozwoju nadmiernej odpowiedzi immunologicznej, co może skutkować chorobą autoimmunologiczną tarczycy.¹

Zrozumienie złożonej etiologii nadczynności tarczycy jest kluczowe dla prawidłowej diagnostyki i leczenia tej choroby. Różne przyczyny nadczynności tarczycy wymagają odmiennych podejść terapeutycznych, dlatego precyzyjne określenie etiologii ma fundamentalne znaczenie dla wyboru optymalnej strategii leczenia.¹

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Materiały źródłowe

#1 Hyperthyroidism – Wikipedia
https://en.wikipedia.org/wiki/Hyperthyroidism
Hyperthyroidism is a endocrine disease in which the thyroid gland produces excessive amounts of thyroid hormones. […] Graves’ disease is the cause of about 50% to 80% of the cases of hyperthyroidism in the United States. […] Other causes include multinodular goiter, toxic adenoma, inflammation of the thyroid, eating too much iodine, and too much synthetic thyroid hormone. […] The major causes in humans are: Graves’ disease. An autoimmune disease (usually, the most common cause with 50-80% worldwide, although this varies substantially with location- i.e., 47% in Switzerland to 90% in the USA). […] Toxic thyroid adenoma (the most common cause in Switzerland, 53%, thought to be atypical due to a low level of dietary iodine in this country). […] Toxic multinodular goiter. […] Inflammation of the thyroid is called thyroiditis.
#1 Hyperthyroidism Causes and Risk Factors
https://www.everydayhealth.com/hyperthyroidism/causes-risk-factors/
Hyperthyroidism refers to an overactive thyroid gland. […] A common cause of hyperthyroidism is an autoimmune condition called Graves disease. […] I most often see hyperthyroidism due to Graves disease, says Gregory Dodell, MD, assistant clinical professor of medicine, endocrinology, diabetes, and bone disease at the Icahn School of Medicine at Mount Sinai in New York City. This is an autoimmune process, meaning that antibodies are overstimulating the thyroid gland. […] The primary antibody to blame is called the thyrotropin receptor antibody (TRAb). TRAb acts similarly to the brains pituitary gland, which naturally regulates the release of thyroid hormones. But when TRAb becomes active, too, your thyroid hormone levels skyrocket. This, in essence, is how Graves disease causes hyperthyroidism.
#1 Understanding Hyperthyroidism ( Overactive Thyroid Gland ): Causes, Symptoms, and Treatment Options | The American Journal of Patient Health Info
https://ajphi.org/ajphi/article/view/38?articlesBySimilarityPage=1
Hyperthyroidism occurs when you have an excess amount of thyroid hormone produced by your thyroid gland. […] The most common cause of hyperthyroidism is Graves disease. It is an autoimmune condition where the body produces antibodies that stimulate the thyroid. […] Graves disease (GD) is the most common cause of hyperthyroidism in developed countries. It is more commonly seen between people of 30 and 60 years, with 5-10 times increased frequency in women. About 79% of the people are genetically predisposed, and about 21% of them have some environmental factors as a risk factor. […] Graves’ Disease: This is known as the most common cause of hyperthyroidism. It is an autoimmune disorder where the body produces antibodies called thyroid-stimulating immunoglobulins (TSI) that stimulate the thyroid gland to produce excess hormones, leading to hyperthyroidism symptoms.
#1 Hyperthyroidism (overactive thyroid) | Doctor
https://patient.info/doctor/hyperthyroidism
Hyperthyroidism is overactivity of the thyroid gland, which results in a number of symptoms and signs. It can be primary or secondary: […] Causes of hyperthyroidism (aetiology)6 […] Graves’ disease is the most common cause of thyrotoxicosis. […] Thyrotoxicosis due to toxic nodular goitre is more common in people aged over 60 years. […] Thyroiditis, in which destruction of thyroid cells causes release of thyroid hormones into the circulation, is implicated in about 10% of thyrotoxicosis cases. […] Other causes include exogenous thyroid hormone excess, drug-induced hyperthyroidism, TSH-secreting pituitary adenomas and pituitary resistance to thyroid hormones. […] Three gene regions consistently linked to Graves’ hyperthyroidism are the human leukocyte antigen region, CTLA4 and PTPN22, all of which encode proteins that are involved in immune function and linked to the cause of other autoimmune disorders.
#1 Hyperthyroidism | Endocrine Conditions
https://www.yourhormones.info/endocrine-conditions/hyperthyroidism/
Hyperthyroidism is a common condition where the thyroid gland becomes overactive and produces too much thyroid hormone. […] What causes hyperthyroidism? […] There are a number of different causes of hyperthyroidism, including: Autoimmune thyroid disease or Graves’ disease the most common cause of hyperthyroidism (80% of all cases). This affects women more commonly than men and is due to the production of special proteins (called antibodies) that attack the thyroid gland. The antibodies fool the thyroid gland into thinking that more thyroid hormone production is needed, which results in hyperthyroidism. […] Toxic thyroid nodule or nodules the second most common cause of hyperthyroidism (15% of cases). One or several thyroid nodule(s) (lumps) work independently from the rest of the thyroid gland and produce too much thyroid hormone.
#1 Hyperthyroidism – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK537053/
Hyperthyroidism is a common thyroid disorder with multiple underlying etiologies. This disease is characterized by excess thyroid hormone production. […] Hyperthyroidism has multiple etiologies, clinical manifestations, and treatment modalities. […] The 3 most common etiologies of hyperthyroidism include: Graves disease, Toxic multinodular goiter (TMNG), Toxic adenoma. […] Other less common etiologies of hyperthyroidism include: Iodine-induced hyperthyroidism, TSH-secreting pituitary adenomas, Conditions associated with high human chorionic gonadotrophin levels, Ectopic thyroid in struma ovarii, Extensive metastasis from functionally differentiated thyroid carcinoma, Drug-induced thyroiditis, Other thyroiditis, Factitious thyroiditis. […] Graves disease is the most common cause of hyperthyroidism in the United States and most Western countries. […] As Graves disease is autoimmune in etiology, this form of hyperthyroidism tends to manifest itself in younger populations. In older adults and people living in regions of iodine deficiency, toxic multinodular goiter is the most common cause of hyperthyroidism.
#1 Hyperthyroidism (Overactive Thyroid) – NIDDK
https://www.niddk.nih.gov/health-information/endocrine-diseases/hyperthyroidism
Hyperthyroidism has several causes, including […] Graves disease, overactive thyroid nodules, inflammation of the thyroid gland, called thyroiditis, too much iodine, too much thyroid hormone medicine, a noncancerous tumor of the pituitary gland. […] Graves disease, the most common cause of hyperthyroidism, is an autoimmune disorder. With this disease, your immune system attacks the thyroid and causes it to make too much thyroid hormone. […] Overactive thyroid nodules, or lumps in your thyroid, are common and usually not cancerous. However, one or more nodules may become overactive and produce too much thyroid hormone. […] Thyroiditis is inflammation of your thyroid gland. Some types of thyroiditis can cause thyroid hormone to leak out of your thyroid gland into your bloodstream. […] Your thyroid uses iodine to make thyroid hormone. How much iodine you consume affects how much thyroid hormone your thyroid makes. In some people, consuming large amounts of iodine may cause the thyroid to make too much thyroid hormone. […] In some rare cases, a noncancerous tumor of the pituitary gland, located at the base of the brain, can cause hyperthyroidism.
#1
https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/causes/
An increased level of iodine in your body can cause your thyroid to produce excess thyroid hormones. […] Other possible causes of an overactive thyroid include: high levels of a substance called human chorionic gonadotrophin in your body this can happen in early pregnancy, a multiple pregnancy or a molar pregnancy (where a lump of abnormal cells grows in the womb instead of a healthy foetus), a pituitary adenoma a non-cancerous (benign) tumour in the pituitary gland (a gland at the base of the brain that can affect the level of hormones produced by your thyroid), thyroiditis swelling (inflammation) of your thyroid, which can cause extra thyroid hormones to be produced, thyroid cancer rarely, a cancerous thyroid tumour can affect the production of thyroid hormones.
#1 Hyperthyroidism: Diagnosis and Treatment | AAFP
https://www.aafp.org/pubs/afp/issues/2016/0301/p363.html
Toxic multinodular goiter is the second most common cause of hyperthyroidism in the United States and the most common cause in older persons living in iodine-deficient areas. Over time, nodules arise from the frequent replication of clonogenic cells that leads to a somatic activating mutation of TSH receptors. A single nodule is called a toxic adenoma (Plummer disease). […] In contrast with these three disorders, painless or transient (silent) thyroiditis causes a destruction of thyroid follicles via an autoimmune mechanism and a release of preformed thyroid hormones into the circulation. […] Gestational hyperthyroidism develops in the first trimester of pregnancy as a result of the stimulatory action of placental beta human chorionic gonadotropin (-hCG), which shares structural features with TSH, on the thyroid gland. Other rare causes of hyperthyroidism are TSH-secreting pituitary adenoma, metastatic follicular thyroid cancer, and struma ovarii.
#1 Diagnosing Hyperthyroidism | NYU Langone Health
https://nyulangone.org/conditions/hyperthyroidism/diagnosis
Hyperthyroidism can also occur during an episode of thyroiditis, which is when an inflammatory problem in the thyroid gland triggers the release of stored thyroid hormone. Typically, this release can cause a person to develop acute thyrotoxicosis, which is when an excessive amount of thyroid hormones are present in the body. This is sometimes followed by hypothyroidism.
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https://healthmatch.io/hyperthyroidism/what-causes-hyperthyroidism
Hyperthyroidism is a condition in which your thyroid gland produces more hormones than your body needs. […] 80% of diagnosed hyperthyroidism is due to Graves disease, making it the most common cause of overactive thyroid. Graves’ disease is an autoimmune disorder in which the immune system attacks the thyroid gland causing it to overproduce hormones. […] Another common cause of hyperthyroidism is thyroiditis, an inflammation of the thyroid gland that causes thyroid hormones to leak into your bloodstream. It raises your amount of thyroid hormones above normal levels. […] Certain foods are high in iodine, such as seafood, seaweed, and dairy. Your body doesn’t make iodine, so some amount in your diet is necessary. However, if you consume too much, your thyroid will produce excess thyroid hormones leading to hyperthyroidism.
#1 Overactive thyroid | NHS inform
https://www.nhsinform.scot/illnesses-and-conditions/glands/overactive-thyroid/
In Graves disease, it attacks the thyroid gland, which leads to an overproduction of the thyroid hormones. […] It is not known what triggers the immune system to do this. Like many autoimmune conditions, it is thought that a combination of both genetic and environmental factors could be involved. […] Toxic thyroid nodules account for about 1 in 20 cases of hyperthyroidism. […] Iodine contained in the food you eat is used by your thyroid gland to produce the thyroid hormones thyroxine and triiodothyronine. However, taking additional iodine in supplements can cause your thyroid gland to produce too much thyroxine or triiodothyronine. […] Amiodarone can cause a type of hyperthyroidism usually more severe and difficult to treat through a harmful effect on thyroid tissue. This type of hyperthyroidism is called amiodarone-induced hyperthyroidism. […] In rare cases, you may develop an overactive thyroid as a result of thyroid cancer that starts in your thyroid follicles. This can occur if cancer cells in your thyroid gland begin to produce thyroxine or triiodothyronine.
#1 Patient education: Hyperthyroidism (overactive thyroid) (Beyond the Basics) – UpToDate
https://www.uptodate.com/contents/hyperthyroidism-overactive-thyroid-beyond-the-basics
Hyperthyroidism is the medical term for an overactive thyroid (the prefix „hyper” means excessive). In people with hyperthyroidism, the thyroid gland produces too much thyroid hormone. When this occurs, the body’s metabolism is increased, which can cause a variety of symptoms. […] Graves’ disease is the most common cause of hyperthyroidism. It is not clear why Graves’ disease develops in most people, although it is more common in certain families. […] In people with Graves’ disease, the immune system produces an antibody that behaves like TSH in that it stimulates the thyroid gland to produce too much thyroid hormone. […] One or more thyroid nodules (small growths or lumps in the thyroid gland) can produce too much thyroid hormone. […] Painless („silent or lymphocytic”) thyroiditis and postpartum thyroiditis are disorders in which the thyroid becomes temporarily inflamed and releases thyroid hormone stores into the bloodstream, causing hyperthyroidism. […] Subacute (granulomatous) thyroiditis is thought to be caused by a virus. […] Taking too much thyroid hormone medication for hypothyroidism increases blood levels into the range seen in people with hyperthyroidism.
#1 Hyperthyroidism – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK537053/
Factitious thyroiditis is thyrotoxicosis associated with inappropriate or excessive use of pharmaceutical thyroid hormone. […] Hyperthyroidism develops about 2-12 weeks after exposure to excessive iodine. […] The pathophysiology of hyperthyroidism depends on the particular variant of hyperthyroidism. […] The antibodies stimulate the TSH receptor (TSHR), leading to increased production and release of thyroid hormones. […] Thyroiditis results in the transient increase in circulating thyroid hormone resulting from inflammation or destruction of the thyroid follicular cells. […] Various etiologies of thyroiditis have this common pathophysiology but vary in their clinical presentations.
#1 Hyperthyroidism – Wikipedia
https://en.wikipedia.org/wiki/Hyperthyroidism
Thyrotoxicosis can also occur after taking too much thyroid hormone in the form of supplements, such as levothyroxine. […] Hypersecretion of thyroid stimulating hormone (TSH), which in turn is almost always caused by a pituitary adenoma, accounts for much less than 1 percent of hyperthyroidism cases.
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https://www2.hse.ie/conditions/overactive-thyroid-hyperthyroidism/causes/
Other possible causes of an overactive thyroid include: high levels of a hormone called human chorionic gonadotropin – this can happen in early pregnancy, a multiple pregnancy or a molar pregnancy, a pituitary adenoma – a non-cancerous tumour of the pituitary gland, thyroiditis – inflammation of the thyroid, thyroid cancer (rarely).
#1 Hyperthyroidism (Overactive Thyroid): Symptoms & Treatment
https://my.clevelandclinic.org/health/diseases/14129-hyperthyroidism
Hyperthyroidism, also called overactive thyroid, is a condition where your thyroid makes and releases high levels of thyroid hormone. It has multiple possible causes. […] Medical conditions and situations that can cause hyperthyroidism include: […] Graves disease: This is an autoimmune condition that makes your thyroid overactive. Graves disease is the most common cause of hyperthyroidism. […] Thyroid nodules: These are lumps or growths of cells in your thyroid gland. They can sometimes produce excess thyroid hormone. […] Thyroiditis: Thyroiditis is inflammation of your thyroid gland. It can cause hyperthyroidism temporarily. […] Consuming excess iodine: Consuming too much iodine (through foods or medications) can cause your thyroid to produce more thyroid hormone. […] TSH-releasing pituitary adenoma (thyrotropinoma): This is a growth in your pituitary gland that releases excess thyroid-stimulating hormone (TSH). […] Factors that increase your risk of developing hyperthyroidism include: […] Biological family history of thyroid disease and/or autoimmune conditions. […] Hyperthyroidism is a treatable condition. Most people do well with treatment.
#1 Hyperthyroidism Causes and Risk Factors
https://www.everydayhealth.com/hyperthyroidism/causes-risk-factors/
Like Graves disease, thyroiditis may be the result of antibodies that attack and inflame your thyroid gland. […] Certain drugs can also destroy thyroid cells, leading to this condition. […] Excess iodine can also lead to an overactive thyroid. […] A family history of autoimmune diseases can also increase your risk for Graves disease. […] If you have a genetic disposition for Graves disease, high amounts of stress and smoking cigarettes can increase your risk of developing hyperthyroidism at some point in the future.
#1 Hyperthyroidism and Thyrotoxicosis: Practice Essentials, Background, Pathophysiology
https://emedicine.medscape.com/article/121865-overview
Hyperthyroidism is a set of disorders that involve excess synthesis and secretion of thyroid hormones by the thyroid gland, which leads to the hypermetabolic condition of thyrotoxicosis. […] The most common forms of hyperthyroidism include diffuse toxic goiter (Graves disease), toxic multinodular goiter, and toxic adenoma. […] The most common cause of thyrotoxicosis is Graves disease (50-60% of cases). […] Genetic factors appear to influence the incidence of thyrotoxicosis. Autoimmune thyroid disease, including Hashimoto hypothyroidism and Graves disease, often occurs in multiple members of a family. […] Several genetic syndromes have been associated with hyperthyroidism, especially autoimmune thyroid disease. […] A number of disorders of thyroid function have been found to be caused by mutations in the TSHR gene, which encodes the TSH receptor protein. […] Iodine intake also appears to influence the occurrence of thyrotoxicosis. […] The most reliable screening measure of thyroid function in the healthy ambulatory adult population is the TSH level.
#1 Hyperthyroidism: Symptoms, treatment, causes, and diet
https://www.medicalnewstoday.com/articles/9153
Hyperthyroidism, or overactive thyroid, occurs when the thyroid gland produces too much of certain hormones. […] There are various possible causes of hyperthyroidism, including the below. […] Graves disease is an autoimmune condition and the most common cause of hyperthyroidism, accounting for over 70% of cases. […] The condition can affect the eyes, causing protracted eyelids, bulging eyes, double vision, and swelling around the eyes. […] Thyroid nodules are lumps that develop in the thyroid gland. It is unclear why they occur. […] These lumps may contain abnormal thyroid tissue, but they are usually benign or noncancerous. They affect the regular function of the thyroid, causing overactive thyroid. […] Taking additional iodine in supplements can cause the thyroid gland to produce too many of the hormones.
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#1 Hyperthyroidism | American Thyroid Association
https://www.thyroid.org/hyperthyroidism/
Hyperthyroidism can be caused by an autoimmune condition (Graves disease), inflammation of the thyroid (thyroiditis), or due to thyroid nodules making too much thyroid hormone (hot nodule or toxic multinodular goiter). […] Graves disease is the most common cause of hyperthyroidism. It is an autoimmune thyroid condition caused by antibodies that stimulate all the cells in the thyroid gland to make too much thyroid hormone. […] A toxic nodule means that there is one area of your thyroid (a nodule) making too much thyroid hormone (also called a hot nodule). A toxic multi-nodular goiter means that there are several nodules making too much thyroid hormone. […] Thyroiditis is due to inflammation of your thyroid gland. This can cause the thyroid hormones inside the thyroid gland to leak out into the blood stream, resulting in too much thyroid hormone in the body.
#1 Hyperthyroidism – Thyroid UK
https://thyroiduk.org/if-you-are-hyperthyroid/about-hyperthyroidism/overview-of-hyperthyroidism/
Research has shown that the body itself makes antibodies to the thyroid tissue which initially may cause overproduction of thyroid hormone, but, in time, this effect may burn itself out and then the receptors become insensitive and the thyroid production starts to become affected the other way; resulting eventually in underproduction of thyroid hormone. […] For reasons which may not be clear, but again are sometimes the result of major traumatic life events, the thyroid producing cells simply overproduce. […] The overactive thyroid is usually enlarged and clearly visible, a condition most often seen in young women. […] Hyperthyroidism was first described as far back as 1835, by an Irish physician, Robert Graves; and a German physician, Karl von Basedow, hastened to write a paper about it in 1840. […] In general, it is diagnosed without difficulty. Its treatment, however, is often not at all satisfactory.
#1 Hyperthyroidism – Thyroid UK
https://thyroiduk.org/if-you-are-hyperthyroid/about-hyperthyroidism/overview-of-hyperthyroidism/
pituitary problems: rarely, the pituitary produces too much TSH, which over-stimulates the thyroid. […] very rarely, cancer. […] There are two groups of problems which can turn the thyroid into an overactive state. Firstly, there may be a control problem. This can originate right at the top of the chain of command. […] The hypothalamus may produce more of the Thyrotrophin Release Hormone (TRH), thus causing overactivity in TSH production, and hence overactivity of the thyroid itself. […] More commonly, the pituitary itself may start producing more TSH. This can occur as a result of a pituitary adenoma, the growth-producing the hormone in an uncontrolled fashion. […] Most causes of overproduction of thyroid hormone, however, occur in the gland itself. The receptors which respond to TSH may over-respond and react by overproduction of the thyroid hormones.
#1 Disorders that cause hyperthyroidism – UpToDate
https://www.uptodate.com/contents/disorders-that-cause-hyperthyroidism
Several different disorders can cause hyperthyroidism. It is essential that the correct cause be identified because appropriate therapy depends upon the underlying mechanism of the hyperthyroidism. […] Hyperthyroidism with a normal or high radioiodine uptake or thyroidal blood flow on ultrasound indicates de novo synthesis of hormone. […] Hyperthyroidism with a near absent radioiodine uptake or low thyroidal blood flow indicates either inflammation and destruction of thyroid tissue with release of preformed hormone into the circulation (destructive thyroiditis) or an extrathyroidal source of thyroid hormone. […] The global prevalence of hyperthyroidism is 0.2 to 1.4 percent. In the United States, the overall prevalence of hyperthyroidism is approximately 1.3 percent, and it increases to 4 to 5 percent in older women. Hyperthyroidism is more common in women than men (5:1 ratio), and in smokers. Graves’ disease is seen most often in younger women and in regions of iodine sufficiency, while toxic nodular goiter is more common in older women and in regions of mild to moderate iodine deficiency.
#1 What Causes Hyperthyroidism? Common Triggers and Underlying Conditions
https://www.rupahealth.com/post/what-causes-hyperthyroidism-common-triggers-and-underlying-conditions
High iodine levels, whether from diet, supplements, or medications, can trigger hyperthyroidism, particularly in individuals with pre-existing thyroid conditions like nodular goiters or latent Graves’ disease. […] Secondary hyperthyroidism is caused by anterior pituitary dysfunction, leading to excessive TSH production, thyroid gland overstimulation, and overproduction of thyroid hormones. […] Individuals with a family history of thyroid disorders, particularly autoimmune thyroid diseases, are more likely to develop hyperthyroidism. Genetic predisposition accounts for up to 80% of the risk for Graves’ disease. […] Women are up to ten times more likely to develop hyperthyroidism than men. […] Research indicates that smokers are at a higher risk of developing Graves’ disease. […] The immune dysfunction observed in autoimmune disease is believed to result from the interplay between environmental exposures and genetic predisposition, leading to the loss of self-tolerance and upregulation of exaggerated immune responses.
#1 What’s Behind Your Overactive Thyroid? Unveiling the Causes of Hyperthyroidism – Doctronic, Your Trusted AI Doctor
https://www.doctronic.ai/conditions-diseases/what-s-behind-your-overactive-thyroid-unveiling-the-causes-of-hyperthyroidism-eUUPbQ
Hyperthyroidism occurs when your thyroid gland produces too much thyroid hormone. But what triggers this overproduction? Let’s explore the main culprits behind this condition. […] Graves’ disease is the most common cause of hyperthyroidism. It’s an autoimmune disorder where your immune system produces antibodies that stimulate your thyroid to overproduce hormones. […] Sometimes, small lumps called nodules can develop in your thyroid gland. These nodules can become 'toxic’, meaning they produce thyroid hormones on their own, ignoring the body’s normal regulatory signals. […] Thyroiditis refers to inflammation of the thyroid gland. This can cause stored thyroid hormones to leak into your bloodstream, resulting in temporary hyperthyroidism. […] Less common causes of hyperthyroidism include excessive iodine intake, certain medications (like amiodarone), and rarely, thyroid cancer. In some cases, the pituitary gland may malfunction and produce too much thyroid-stimulating hormone (TSH). […] Some forms, like Graves’ disease, have a genetic component. […] Pregnancy can trigger thyroiditis leading to temporary hyperthyroidism. […] Identifying the cause of hyperthyroidism is crucial for determining the most effective treatment approach.
#2 Hyperthyroidism: Symptoms, treatment, causes, and diet
https://www.medicalnewstoday.com/articles/9153
Hyperthyroidism, or overactive thyroid, occurs when the thyroid gland produces too much of certain hormones. […] There are various possible causes of hyperthyroidism, including the below. […] Graves disease is an autoimmune condition and the most common cause of hyperthyroidism, accounting for over 70% of cases. […] The condition can affect the eyes, causing protracted eyelids, bulging eyes, double vision, and swelling around the eyes. […] Thyroid nodules are lumps that develop in the thyroid gland. It is unclear why they occur. […] These lumps may contain abnormal thyroid tissue, but they are usually benign or noncancerous. They affect the regular function of the thyroid, causing overactive thyroid. […] Taking additional iodine in supplements can cause the thyroid gland to produce too many of the hormones.
#2
https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/causes/
If you have an overactive thyroid (hyperthyroidism), your thyroid gland produces too much of the thyroid hormones. […] There are a number of conditions that can cause your thyroid to become overactive. […] About 4 in every 5 people with an overactive thyroid gland have a condition called Graves’ disease. […] Graves’ disease is an autoimmune condition where your immune system produces antibodies that cause the thyroid to produce too much thyroid hormone. […] The cause of Graves’ disease is unknown, but it mostly affects young or middle-aged women and often runs in families. Smoking can also increase your risk of getting it. […] Less commonly, your thyroid can become overactive if lumps (nodules) develop on your thyroid. […] Nodules are usually non-cancerous (benign), but they may contain thyroid tissue, which can result in the production of excess thyroid hormones.
#2 Hyperthyroidism (Overactive Thyroid): Symptoms & Treatment
https://my.clevelandclinic.org/health/diseases/14129-hyperthyroidism
Hyperthyroidism, also called overactive thyroid, is a condition where your thyroid makes and releases high levels of thyroid hormone. It has multiple possible causes. […] Medical conditions and situations that can cause hyperthyroidism include: […] Graves disease: This is an autoimmune condition that makes your thyroid overactive. Graves disease is the most common cause of hyperthyroidism. […] Thyroid nodules: These are lumps or growths of cells in your thyroid gland. They can sometimes produce excess thyroid hormone. […] Thyroiditis: Thyroiditis is inflammation of your thyroid gland. It can cause hyperthyroidism temporarily. […] Consuming excess iodine: Consuming too much iodine (through foods or medications) can cause your thyroid to produce more thyroid hormone. […] TSH-releasing pituitary adenoma (thyrotropinoma): This is a growth in your pituitary gland that releases excess thyroid-stimulating hormone (TSH). […] Factors that increase your risk of developing hyperthyroidism include: […] Biological family history of thyroid disease and/or autoimmune conditions. […] Hyperthyroidism is a treatable condition. Most people do well with treatment.
#2 What Causes Hyperthyroidism? Common Triggers and Underlying Conditions
https://www.rupahealth.com/post/what-causes-hyperthyroidism-common-triggers-and-underlying-conditions
More than 12% of the United States population will develop a thyroid condition during their lifetime. Hyperthyroidism is one type of thyroid disease characterized by the excess production of thyroid hormones, leading to an overactive metabolism. […] Understanding the causes of hyperthyroidism enhances diagnostic accuracy and treatment efficacy. While autoimmune conditions like Graves’ disease are the most common culprits, other factors that you may not be aware of might be triggering excess hormone production. […] The most common reasons hyperthyroidism occurs are autoimmunity and hyperfunctioning thyroid nodules. […] Graves’ disease is an autoimmune thyroid disease and the leading cause of hyperthyroidism, attributed to nearly 80% of all cases. […] The exact cause of Graves’ disease is not fully understood, but, as with any autoimmune disease, it is believed to be influenced by genetic and environmental factors. Stress, infections, and smoking have been identified as potential triggers for the onset of the disease in genetically predisposed individuals.
#2 Hyperthyroidism: Diagnosis and Treatment | AAFP
https://www.aafp.org/pubs/afp/issues/2016/0301/p363.html
Toxic multinodular goiter is the second most common cause of hyperthyroidism in the United States and the most common cause in older persons living in iodine-deficient areas. Over time, nodules arise from the frequent replication of clonogenic cells that leads to a somatic activating mutation of TSH receptors. A single nodule is called a toxic adenoma (Plummer disease). […] In contrast with these three disorders, painless or transient (silent) thyroiditis causes a destruction of thyroid follicles via an autoimmune mechanism and a release of preformed thyroid hormones into the circulation. […] Gestational hyperthyroidism develops in the first trimester of pregnancy as a result of the stimulatory action of placental beta human chorionic gonadotropin (-hCG), which shares structural features with TSH, on the thyroid gland. Other rare causes of hyperthyroidism are TSH-secreting pituitary adenoma, metastatic follicular thyroid cancer, and struma ovarii.
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#2 Hyperthyroidism | American Thyroid Association
https://www.thyroid.org/hyperthyroidism/
Hyperthyroidism can be caused by an autoimmune condition (Graves disease), inflammation of the thyroid (thyroiditis), or due to thyroid nodules making too much thyroid hormone (hot nodule or toxic multinodular goiter). […] Graves disease is the most common cause of hyperthyroidism. It is an autoimmune thyroid condition caused by antibodies that stimulate all the cells in the thyroid gland to make too much thyroid hormone. […] A toxic nodule means that there is one area of your thyroid (a nodule) making too much thyroid hormone (also called a hot nodule). A toxic multi-nodular goiter means that there are several nodules making too much thyroid hormone. […] Thyroiditis is due to inflammation of your thyroid gland. This can cause the thyroid hormones inside the thyroid gland to leak out into the blood stream, resulting in too much thyroid hormone in the body.
#2 Hyperthyroidism | Endocrine Conditions
https://www.yourhormones.info/endocrine-conditions/hyperthyroidism/
Thyroid inflammation or thyroiditis a rare cause of hyperthyroidism (12% of cases) usually due to a viral illness, which causes inflammation and tissue destruction of the thyroid gland, leading to release of stored thyroid hormones. […] Drugs drugs being used to treat other conditions can cause hyperthyroidism. The most common is amiodarone, a drug used to control an irregular heartbeat. […] There are some other extremely rare causes of hyperthyroidism such as benign tumours of the pituitary gland that produce an excess of thyroid stimulating hormone.
#2 OVERACTIVE THYROID (HYPERTHYROIDISM) – Symptoms, Causes, Risk Groups and Treatment – Ecosh
https://ecosh.com/overactive-thyroid-hyperthyroidism-symptoms-causes-risk-groups-and-treatment/
Hyperthyroidism means that the thyroid gland is overactive. As a result, it makes too much of its hormone and causes your body to use energy too quickly. […] Most common cause of hyperthyroidism is Graves disease (affects about 70 % of people with an overactive thyroid). However, nodules on the thyroid (toxic nodular goiter or multinodular goiter) can also cause the gland to overproduce its hormones. […] Overactive thyroid (hyperthyroidism) may be both caused by other diseases that affect the way the thyroid gland works. […] In this autoimmune disorder, which is the most common cause of hyperthyroidism the entire thyroid gland might be overactive and secrete too much hormone (also called diffuse toxic goiter (enlarged thyroid gland)). […] Excessive iodine (a key ingredient in tetraiodothyronine (T4) and triiodothyronine (T3), which are two primary hormones that control how your cells use energy). If you have too much iodine (this mineral is used to make thyroid hormones) in your body, the thyroid makes more thyroid hormones than it needs. […] In case this disorder or inflammation of the thyroid, the thyroid releases hormones that were stored there, meaning T4 and T3 will leak out of the gland. This condition can be either painful or not felt at all, and can last for a few weeks or months.
#2 Hyperthyroidism and Gravesâ Disease (for Parents) | Nemours KidsHealth
https://kidshealth.org/en/parents/hyperthyroidism.html
If the thyroid is overactive, it releases too much thyroid hormone into the bloodstream, causing hyperthyroidism. […] The three main causes of hyperthyroidism are: Graves’ disease. This is the most common cause of hyperthyroidism in children. It happens when the body produces antibodies that make the thyroid gland overactive. […] Thyroid gland inflammation (thyroiditis). This causes the thyroid gland to leak too much thyroid hormone into the blood. […] Thyroid nodules (growths in the thyroid gland). These can sometimes make large amounts of thyroid hormones, causing symptoms of hyperthyroidism.
#2 What Causes Hyperthyroidism? Common Triggers and Underlying Conditions
https://www.rupahealth.com/post/what-causes-hyperthyroidism-common-triggers-and-underlying-conditions
High iodine levels, whether from diet, supplements, or medications, can trigger hyperthyroidism, particularly in individuals with pre-existing thyroid conditions like nodular goiters or latent Graves’ disease. […] Secondary hyperthyroidism is caused by anterior pituitary dysfunction, leading to excessive TSH production, thyroid gland overstimulation, and overproduction of thyroid hormones. […] Individuals with a family history of thyroid disorders, particularly autoimmune thyroid diseases, are more likely to develop hyperthyroidism. Genetic predisposition accounts for up to 80% of the risk for Graves’ disease. […] Women are up to ten times more likely to develop hyperthyroidism than men. […] Research indicates that smokers are at a higher risk of developing Graves’ disease. […] The immune dysfunction observed in autoimmune disease is believed to result from the interplay between environmental exposures and genetic predisposition, leading to the loss of self-tolerance and upregulation of exaggerated immune responses.
#2 Overactive thyroid | Healthify
https://healthify.nz/health-a-z/o/overactive-thyroid
An overactive thyroid (hyperthyroidism) is when your thyroid gland makes too much thyroid hormone. […] Common causes include Graves disease, thyroid nodules, thyroiditis and some medicines, eg, amiodarone. […] An overactive thyroid can be caused by a number of conditions: Graves disease. This is the most common cause. It is an autoimmune disease in which your body’s immune system mistakenly attacks your thyroid gland. Sometimes this condition runs in families. […] Thyroid nodules. These are benign (non-cancerous) lumps that grow on your thyroid. They can produce extra thyroid hormones. […] Too much iodine in your body. This can be caused by taking iodine supplements such as kelp or seaweed. […] Thyroiditis (inflammation of your thyroid gland). This can be caused by a virus or can happen soon after having a baby. […] Some medicines such as lithium or amiodarone can cause an overactive thyroid. […] Thyroid cancer. This is rare, but a thyroid cancer can affect the production of thyroid hormones.
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https://www.medichecks.com/blogs/thyroid/what-is-an-overactive-thyroid
An overactive thyroid is where the thyroid gland makes too many thyroid hormones, which can include thyroxine (T4) and triiodothyronine (T3). This condition is also commonly known as hyperthyroidism. […] Causes of hyperthyroidism include: Graves disease an autoimmune thyroid condition where the immune system makes antibodies that cause the thyroid to overproduce thyroid hormones. This is the most common cause of hyperthyroidism (about four in five people with an overactive thyroid have Graves disease). […] Thyroiditis inflammation of the thyroid gland, which can cause excess thyroid hormone production. […] Thyroid lumps (nodules) lumps containing thyroid tissue that can make extra thyroid hormones. […] Excess iodine too much iodine can cause temporary hyperthyroidism. Foods, such as fish and dairy, contain iodine, and its also present in some medications like amiodarone, which is used to treat an irregular heartbeat.
#2 Hyperthyroidism | Graves’ Disease | Overactive Thyroid | MedlinePlus
https://medlineplus.gov/hyperthyroidism.html
Hyperthyroidism, or overactive thyroid, happens when your thyroid gland makes more thyroid hormones than your body needs. […] Hyperthyroidism has several causes. They include: Graves’ disease, an autoimmune disorder in which your immune system attacks your thyroid and causes it to make too much hormone. This is the most common cause. […] Thyroid nodules, which are growths on your thyroid. They are usually benign (not cancer). But they may become overactive and make too much thyroid hormone. Thyroid nodules are more common in older adults. […] Thyroiditis, inflammation of the thyroid. It causes stored thyroid hormone to leak out of your thyroid gland. […] Too much iodine. Iodine is found in some medicines, cough syrups, seaweed and seaweed-based supplements. Taking too much of them can cause your thyroid to make too much thyroid hormone. […] Too much thyroid medicine. This can happen if people who take thyroid hormone medicine for hypothyroidism (underactive thyroid) take too much of it.
#2
https://healthmatch.io/hyperthyroidism/what-causes-hyperthyroidism
Thyroid nodules are growths on your thyroid. The nodules are benign (non-cancerous) but may cause your thyroid gland to make too much thyroid hormone. […] You may develop hypothyroidism (underactive thyroid) if your thyroid makes too few hormones. This is usually treated with daily synthetic thyroid hormone replacement. If the prescribed dosage is too high, it can cause unwanted excess thyroid hormone, leading to hyperthyroidism. […] Hyperthyroidism (overactive thyroid) tends to be caused by Graves’ disease, thyroiditis, consuming large amounts of iodine, thyroid nodules, or taking too high a dose of thyroid hormone medication. […] More rarely, hyperthyroidism may be caused by cancer, pituitary gland problems, or elevated levels of chorionic gonadotropin.
#2 Hyperthyroidism – Hormonal and Metabolic Disorders – Merck Manual Consumer Version
https://www.merckmanuals.com/home/hormonal-and-metabolic-disorders/thyroid-gland-disorders/hyperthyroidism
Other causes of hyperthyroidism include some medications, including too much thyroid hormone taken orally, and rarely, overstimulation due to an overactive pituitary gland. […] Medications and iodine can cause hyperthyroidism. […] An overactive pituitary gland can produce too much thyroid-stimulating hormone, which in turn leads to overproduction of thyroid hormones. […] Other rare causes of hyperthyroidism include certain abnormalities of the placenta that produce excess levels of the hormone human chorionic gonadotropin, which can stimulate the thyroid gland to produce excess thyroid hormone, certain tumors of the ovary that contain thyroid tissue, and thyroid cancer that has spread to other areas of the body.
#2 Hyperthyroidism Causes and Risk Factors
https://www.everydayhealth.com/hyperthyroidism/causes-risk-factors/
Hyperthyroidism refers to an overactive thyroid gland. […] A common cause of hyperthyroidism is an autoimmune condition called Graves disease. […] I most often see hyperthyroidism due to Graves disease, says Gregory Dodell, MD, assistant clinical professor of medicine, endocrinology, diabetes, and bone disease at the Icahn School of Medicine at Mount Sinai in New York City. This is an autoimmune process, meaning that antibodies are overstimulating the thyroid gland. […] The primary antibody to blame is called the thyrotropin receptor antibody (TRAb). TRAb acts similarly to the brains pituitary gland, which naturally regulates the release of thyroid hormones. But when TRAb becomes active, too, your thyroid hormone levels skyrocket. This, in essence, is how Graves disease causes hyperthyroidism.
#2 What Causes Hyperthyroidism? Common Triggers and Underlying Conditions
https://www.rupahealth.com/post/what-causes-hyperthyroidism-common-triggers-and-underlying-conditions
Toxic multinodular goiter (TMNG), or Plummer’s disease, is a thyroid disorder characterized by multiple nodules in the thyroid gland and the second most common cause of hyperthyroidism. […] These nodules become overactive („toxic”), functioning independently of the normal regulatory control of TSH, and release too much T3 and T4. […] Thyroid adenomas are benign (non-cancerous), solitary thyroid nodules. A single nodule is called a toxic adenoma when it produces excess thyroid hormones independently of the body’s regulatory signals. […] Several other conditions can less frequently trigger the thyroid gland to release excessive thyroid hormones. […] Thyroiditis is inflammation of the thyroid gland. There are many types of thyroiditis, many of which begin with the destruction of thyroid cells via an inflammatory immune mechanism, releasing excessive amounts of thyroid hormones into circulation.
#2 Hyperthyroidism – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK537053/
Factitious thyroiditis is thyrotoxicosis associated with inappropriate or excessive use of pharmaceutical thyroid hormone. […] Hyperthyroidism develops about 2-12 weeks after exposure to excessive iodine. […] The pathophysiology of hyperthyroidism depends on the particular variant of hyperthyroidism. […] The antibodies stimulate the TSH receptor (TSHR), leading to increased production and release of thyroid hormones. […] Thyroiditis results in the transient increase in circulating thyroid hormone resulting from inflammation or destruction of the thyroid follicular cells. […] Various etiologies of thyroiditis have this common pathophysiology but vary in their clinical presentations.
#2 Hyperthyroidism (Overactive Thyroid) – Symptoms and causes
https://www.utentclinic.com/news/what-are-causes-of-hyperthyroidism
What are causes of Hyperthyroidism […] Hyperthyroidism affects around 1 in 100 people in the United States of America. Women are more likely to have a hyperthyroid compared to men. In fact, nearly 1 in every 10 women have hyperthyroidism. […] Hyperthyroidism causes […] For every condition theres a root cause. A thyroid condition such as hyperthyroidism may be caused by inflammation. […] Other illnesses may bring it on (Graves disease) – Sometimes illnesses such as Graves disease can also result in the development of the condition. […] It could also be a case of a tumor of the pituitary gland – This would have to be removed through. […] Thyroid medication may be too much – While thyroid meds are there to help it can also cause the opposite effect when it is taken in excess.
#2
https://healthmatch.io/hyperthyroidism/what-causes-overactive-thyroid
Hyperthyroidism or overactive thyroid occurs when your thyroid makes more hormones than your body needs. […] Many factors can contribute to a hyperthyroidism diagnosis, including: […] Most people with hyperthyroidism also have Graves disease. […] Graves disease is an autoimmune disorder that causes your immune system to attack your thyroid gland as if it were an invader. This can cause your thyroid to become overactive. […] Certain medications can cause your body to produce too many thyroid hormones. Medications containing iodine that are used to treat an irregular heartbeat are an example. […] While less common, nodules can grow on your thyroid and cause an increase in hormone production. […] In rare cases, thyroid cancer has been known to cause the thyroid gland to produce too many hormones. […] The condition is more common among women over the age of 60 and people with Graves disease. Having a family history of autoimmune conditions or consuming excess iodine may also increase your chances of developing hyperthyroidism.
#2 Hyperthyroidism: Diagnosis and Treatment | AAFP
https://www.aafp.org/pubs/afp/issues/2016/0301/p363.html
Hyperthyroidism is an excessive concentration of thyroid hormones in tissues caused by increased synthesis of thyroid hormones, excessive release of preformed thyroid hormones, or an endogenous or exogenous extrathyroidal source. The most common causes of an excessive production of thyroid hormones are Graves disease, toxic multinodular goiter, and toxic adenoma. […] The common endogenous causes of hyperthyroidism are Graves disease, toxic multinodular goiter, toxic adenoma, and painless thyroiditis. Graves disease, the most common cause of hyperthyroidism in the United States, is an autoimmune disorder in which thyroid-stimulating antibodies activate thyroid-stimulating hormone (TSH) receptors, triggering thyroid hormone synthesis. Risk factors for Graves disease include female sex and personal or family history of an autoimmune disorder.
#2 Hyperthyroidism and Thyrotoxicosis: Practice Essentials, Background, Pathophysiology
https://emedicine.medscape.com/article/121865-overview
Hyperthyroidism is a set of disorders that involve excess synthesis and secretion of thyroid hormones by the thyroid gland, which leads to the hypermetabolic condition of thyrotoxicosis. […] The most common forms of hyperthyroidism include diffuse toxic goiter (Graves disease), toxic multinodular goiter, and toxic adenoma. […] The most common cause of thyrotoxicosis is Graves disease (50-60% of cases). […] Genetic factors appear to influence the incidence of thyrotoxicosis. Autoimmune thyroid disease, including Hashimoto hypothyroidism and Graves disease, often occurs in multiple members of a family. […] Several genetic syndromes have been associated with hyperthyroidism, especially autoimmune thyroid disease. […] A number of disorders of thyroid function have been found to be caused by mutations in the TSHR gene, which encodes the TSH receptor protein. […] Iodine intake also appears to influence the occurrence of thyrotoxicosis. […] The most reliable screening measure of thyroid function in the healthy ambulatory adult population is the TSH level.
#2 Graves’ Disease: Causes, Symptoms and Treatment | Live Science
https://www.livescience.com/34730-graves-disease-overactive-thyroid.html
Graves’ disease is an autoimmune disorder where misplaced attacks from the immune system cause the thyroid gland to become overactive. The result, known as hyperthyroidism, causes the thyroid to produce an excessive amount of the thyroid hormone, thyroxine. […] The reasons behind the autoimmune attacks are still unclear. Various family and twin studies, including a 2010 epidemiological study of patients with Graves’ disease, have suggested that the disease has a hereditary component. Moreover, the likelihood of getting the disease is correlated to the number of affected family members. […] Despite that, the same study also found a higher incidence of the disease occurring in both spouses, which suggests that there’s a small likelihood that the disease is somewhat influenced by environmental conditions. […] Pregnancy could also trigger Graves’ disease. According to the National Women’s Health Information Center, as many as 30 percent of young women who get Graves’ disease have been pregnant in the 12 months prior to the onset of symptoms.
#3 Overactive thyroid | NHS inform
https://www.nhsinform.scot/illnesses-and-conditions/glands/overactive-thyroid/
Overactive thyroid (also known as hyperthyroidism) is a relatively common hormonal condition that occurs when there is too much thyroid hormone in the body. […] In hyperthyroidism, the thyroid gland produces too much thyroxine or triiodothyronine, which speeds up the body’s metabolism. […] There are several possible underlying causes, the most common being Graves disease, in which the body’s immune system targets the thyroid gland and causes it to produce too much of the thyroid hormones. […] Overactive thyroid (hyperthyroidism) occurs when your thyroid gland produces too much of the thyroid hormones thyroxine or triiodothyronine. […] Graves disease is the most common cause of overactive thyroid. […] Graves disease is an autoimmune condition. This means the immune system mistakes something in the body for a toxic substance and attacks it.