Przytarczyca (niedoczynność tarczycy)

Przytarczyca (niedoczynność tarczycy)
Diagnostyka i diagnoza

Niedoczynność tarczycy to stan charakteryzujący się niewystarczającą produkcją hormonów tarczycy, diagnozowany przede wszystkim na podstawie badań laboratoryjnych. Kluczowym markerem jest podwyższony poziom TSH (>4,5 mIU/L), który wskazuje na pierwotną niedoczynność tarczycy, zwłaszcza gdy towarzyszy mu obniżony poziom wolnej tyroksyny (FT4). Subkliniczna niedoczynność tarczycy cechuje się podwyższonym TSH (zwykle <10 mIU/L) przy prawidłowym FT4. W diagnostyce różnicowej uwzględnia się także wtórną niedoczynność tarczycy, gdzie zarówno TSH, jak i FT4 są niskie, co sugeruje patologię przysadki mózgowej. W przypadku podejrzenia autoimmunologicznej etiologii, np. choroby Hashimoto, zaleca się oznaczenie przeciwciał anty-TPO i anty-TG. Badania obrazowe, takie jak ultrasonografia czy scyntygrafia, nie są rutynowe, ale wskazane przy podejrzeniu zmian strukturalnych tarczycy lub obecności guzków.

Diagnostyka niedoczynności tarczycy (przytarczyca)

Badania krwi – podstawowe narzędzie diagnostyczne
Interpretacja wyników badań
Badania przeciwciał tarczycowych
Badania obrazowe w diagnostyce niedoczynności tarczycy
Badanie kliniczne i wywiad medyczny
Diagnostyka subklinicznej niedoczynności tarczycy
Badania przesiewowe w kierunku niedoczynności tarczycy
Monitorowanie leczenia niedoczynności tarczycy

Wyzwania diagnostyczne i możliwe błędy
Znaczenie wczesnej diagnostyki

Kolejne rozdziały

Diagnostyka niedoczynności tarczycy (przytarczyca)

Niedoczynność tarczycy (przytarczyca) to stan kliniczny, w którym gruczoł tarczowy nie produkuje wystarczającej ilości hormonów tarczycy. Diagnostyka tego schorzenia jest kluczowa, ponieważ objawy mogą być niespecyficzne i przypominać inne choroby. Prawidłowe rozpoznanie niedoczynności tarczycy nie opiera się wyłącznie na objawach, ale wymaga przeprowadzenia odpowiednich badań laboratoryjnych¹².

Badania krwi – podstawowe narzędzie diagnostyczne

Badania krwi stanowią najdokładniejszą metodę diagnozowania niedoczynności tarczycy. Są one jedynym wiarygodnym sposobem potwierdzenia obecności choroby, szczególnie we wczesnym stadium¹². Wśród podstawowych badań wykorzystywanych w diagnostyce wymienia się:

Badanie poziomu TSH

Pomiar stężenia hormonu tyreotropowego (TSH) jest najważniejszym i najbardziej czułym testem w diagnostyce niedoczynności tarczycy. Wysoki poziom TSH sugeruje niedoczynność tarczycy, ponieważ przysadka mózgowa produkuje więcej TSH, próbując stymulować tarczycę do wytwarzania większej ilości hormonów¹². Jest to zwykle pierwszy test wykonywany przy podejrzeniu niedoczynności tarczycy¹.

Prawidłowy zakres TSH wynosi zwykle od 0,4 do 4,5 mIU/L. Stężenie TSH powyżej górnej granicy zakresu referencyjnego wskazuje na niedoczynność tarczycy¹².

Badanie poziomu hormonów tarczycowych

W przypadku wykrycia podwyższonego poziomu TSH, kolejnym krokiem jest pomiar poziomu tyroksyny (T4), zwłaszcza wolnej tyroksyny (FT4) w surowicy krwi¹². Niski poziom FT4 w połączeniu z wysokim TSH potwierdza rozpoznanie jawnej niedoczynności tarczycy¹.

W niektórych przypadkach może być również badany poziom trijodotyroniny (T3), chociaż rzadko jest to pomocne w diagnostyce niedoczynności tarczycy, ponieważ jest to ostatni parametr, który ulega zmianie. Pacjenci mogą mieć ciężką niedoczynność tarczycy z wysokim TSH i niskim FT4, ale normalnym poziomem T3¹².

Interpretacja wyników badań

Interpretacja wyników badań laboratoryjnych jest kluczowa dla prawidłowego rozpoznania niedoczynności tarczycy. Wyróżnia się następujące wzorce wyników:

Jawna (kliniczna) niedoczynność tarczycy: podwyższony poziom TSH i obniżony poziom FT4¹²
Subkliniczna niedoczynność tarczycy: podwyższony poziom TSH, ale normalny poziom FT4¹²
Wtórna niedoczynność tarczycy (pochodzenia przysadkowego): niski poziom TSH i niski poziom FT4, wskazujący na problem z przysadką mózgową¹²

Według wytycznych, jawna niedoczynność tarczycy jest diagnozowana, gdy poziom TSH przekracza zakres referencyjny, a poziom FT4 jest poniżej zakresu referencyjnego. Subkliniczna niedoczynność tarczycy charakteryzuje się podwyższonym poziomem TSH (ale poniżej 10 mIU/L) i normalnym poziomem FT4¹².

Badania przeciwciał tarczycowych

W przypadku podejrzenia autoimmunologicznej przyczyny niedoczynności tarczycy, takich jak choroba Hashimoto (zapalenie tarczycy Hashimoto), zaleca się wykonanie badań na obecność przeciwciał tarczycowych¹. Najczęściej oznaczane są:

Przeciwciała przeciwko peroksydazie tarczycowej (anty-TPO) – ich obecność wskazuje na autoimmunologiczne zapalenie tarczycy¹²
Przeciwciała przeciwko tyreoglobulinie (anty-TG) – również związane z autoimmunologicznymi chorobami tarczycy¹

Wykrycie podwyższonych poziomów tych przeciwciał pomaga potwierdzić diagnozę choroby Hashimoto, która jest najczęstszą przyczyną niedoczynności tarczycy w krajach o wystarczającym spożyciu jodu¹.

Badania obrazowe w diagnostyce niedoczynności tarczycy

Badania obrazowe nie są rutynowo wykonywane w diagnostyce niedoczynności tarczycy, ale mogą być przydatne w niektórych przypadkach:

Ultrasonografia tarczycy – może być zalecana w przypadku podejrzenia zmian strukturalnych tarczycy, takich jak wole czy guzki¹²
Scyntygrafia tarczycy – ocenia funkcję gruczołu tarczowego i może pomóc w określeniu przyczyny niedoczynności¹
Test wychwytu radioaktywnego jodu – mierzy, jak wiele radioaktywnego jodu wchłania tarczyca z krwiobiegu, co pomaga ocenić jej funkcję. Niski wychwyt wskazuje na niedoczynność tarczycy¹²

Badania obrazowe są szczególnie ważne w przypadku powiększenia tarczycy lub obecności guzków wyczuwalnych podczas badania fizykalnego¹.

Badanie kliniczne i wywiad medyczny

Chociaż badania laboratoryjne są niezbędne do potwierdzenia diagnozy, badanie kliniczne i dokładny wywiad medyczny pozostają ważnymi elementami procesu diagnostycznego¹. Podczas badania lekarz:

Ocenia objawy pacjenta, takie jak zmęczenie, przyrost masy ciała, suchość skóry, nietolerancja zimna¹
Przeprowadza badanie fizykalne, zwracając uwagę na powiększenie tarczycy, tkliwość lub stan zapalny¹
Zbiera wywiad medyczny, w tym informacje o chorobach autoimmunologicznych, wcześniejszych problemach z tarczycą czy historii rodzinnej¹

Diagnostyka subklinicznej niedoczynności tarczycy

Subkliniczna niedoczynność tarczycy to stan, w którym poziom TSH jest podwyższony, ale poziom hormonów tarczycy pozostaje w granicach normy¹. Pacjenci z subkliniczną niedoczynnością tarczycy mogą nie wykazywać żadnych objawów lub mieć jedynie łagodne objawy¹.

W przypadku stwierdzenia subklinicznej niedoczynności tarczycy, zaleca się:

Wykonanie badania na obecność przeciwciał anty-TPO¹
Powtórzenie badania TSH po 6-12 miesiącach¹²
Rozważenie leczenia hormonalnego, jeśli poziom TSH przekracza 10 mIU/L lub wykryto podwyższony poziom przeciwciał anty-TPO¹²

Badania przesiewowe w kierunku niedoczynności tarczycy

Nie istnieją uniwersalne zalecenia dotyczące badań przesiewowych w kierunku chorób tarczycy u dorosłych¹. Amerykańskie Towarzystwo Tyreologiczne zaleca jednak badania przesiewowe w wieku 35 lat, a następnie co 5 lat, ze szczególnym uwzględnieniem pacjentów z grupy wysokiego ryzyka, takich jak:

Kobiety w ciąży¹
Osoby powyżej 60 roku życia, zwłaszcza kobiety¹²
Pacjenci z cukrzycą typu 1 lub innymi chorobami autoimmunologicznymi¹²
Pacjenci z historią napromieniania szyi¹
Osoby z objawami sugerującymi niedoczynność tarczycy¹

Monitorowanie leczenia niedoczynności tarczycy

Badania funkcji tarczycy odgrywają również kluczową rolę w monitorowaniu leczenia niedoczynności tarczycy¹. Regularne pomiary poziomu TSH pomagają lekarzom ustalić i utrzymać odpowiednią dawkę leków zastępujących hormony tarczycy¹.

Po rozpoczęciu leczenia lewotyroksyną, poziom TSH powinien być kontrolowany co 3 miesiące, aż do stabilizacji¹. Następnie zaleca się coroczne badania kontrolne¹².

Wyzwania diagnostyczne i możliwe błędy

Diagnostyka niedoczynności tarczycy może napotykać pewne wyzwania, które mogą prowadzić do opóźnienia rozpoznania lub błędnej diagnozy¹:

Niespecyficzne objawy, które mogą przypominać inne choroby¹²
Nieprawidłowa interpretacja wyników badań laboratoryjnych, zwłaszcza przy użyciu przestarzałych zakresów referencyjnych¹
Brak rutynowego sprawdzania poziomów hormonów tarczycy podczas regularnych badań¹
Wykonywanie tylko pojedynczego testu (np. tylko TSH) zamiast pełnego panelu tarczycowego¹

Według Amerykańskiego Towarzystwa Tyreologicznego, około 20 milionów Amerykanów doświadcza objawów chorób tarczycy, jednak do 60% z nich nie wie, że mają zaburzenia¹. Nierozpoznana niedoczynność tarczycy może prowadzić do poważnych powikłań zdrowotnych, takich jak osteoporoza, choroby sercowo-naczyniowe i niepłodność¹.

Znaczenie wczesnej diagnostyki

Wczesna i dokładna diagnostyka niedoczynności tarczycy jest kluczowa dla skutecznego leczenia i zapobiegania powikłaniom¹. Leczenie niedoczynności tarczycy jest zwykle proste, bezpieczne i skuteczne, gdy zostanie właściwie dobrane¹.

Pacjenci z objawami sugerującymi niedoczynność tarczycy powinni skonsultować się z lekarzem i poprosić o wykonanie badań krwi¹. Podstawą leczenia jest zastosowanie lewotyroksyny, syntetycznego hormonu tarczycy, który zastępuje hormony, których organizm nie może wytworzyć¹.

Nieleczona niedoczynność tarczycy może prowadzić do poważnych komplikacji, w tym chorób serca, problemów z płodnością, a w skrajnych przypadkach do śpiączki myksedematycznej, która jest stanem zagrażającym życiu¹²².

Kolejne rozdziały

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Wybierz kolejny rozdział z menu poniżej, aby otworzyć nową podstronę kompedium wiedzy i uzyskać szczegółowe informację o leku, substancji lub chorobie.

Materiały źródłowe

#1 Hypothyroidism (underactive thyroid) – Diagnosis and treatment – Mayo Clinic
https://www.mayoclinic.org/diseases-conditions/hypothyroidism/diagnosis-treatment/drc-20350289
The symptoms of hypothyroidism can be different from person to person. And they often look like symptoms of other health problems. Because of that, a diagnosis of hypothyroidism doesn’t rely on symptoms alone. It’s usually based on the results of blood tests. […] The first blood test typically done to diagnose hypothyroidism measures the level of thyroid-stimulating hormone (TSH) in the blood. If it’s high, the test is done again, along with a blood test for the thyroid hormone T-4. If the results show that TSH is high and T-4 is low, then the diagnosis is hypothyroidism. In some cases, the thyroid hormone T-3 may be measured as well. […] If the second test shows high TSH but T-4 and T-3 are in the standard range, then the diagnosis is a condition called subclinical hypothyroidism. It usually doesn’t cause any noticeable symptoms.
#1
https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/diagnosis/
It’s very important that an underactive thyroid (hypothyroidism) is diagnosed as soon as possible. […] Therefore, you should see a GP and ask for a blood test if you repeatedly have symptoms of an underactive thyroid. […] A blood test measuring your hormone levels is the only accurate way to find out whether there’s a problem. […] The test, called a thyroid function test, looks at levels of thyroid-stimulating hormone (TSH) and thyroxine (T4) in the blood. […] A high level of TSH and a low level of T4 in the blood could mean you have an underactive thyroid. […] If your test results show raised TSH but normal T4, you may be at risk of developing an underactive thyroid in the future. […] The GP may recommend that you have a repeat blood test every so often to see whether you eventually develop an underactive thyroid.
#1 Hypothyroidism: Diagnosis and Treatment | AAFP
https://www.aafp.org/pubs/afp/issues/2021/0515/p605.html
Clinical hypothyroidism affects one in 300 people in the United States, with a higher prevalence among female and older patients. […] The signs and symptoms that suggest thyroid dysfunction are nonspecific and nondiagnostic, especially early in disease presentation; therefore, a diagnosis is based on blood levels of thyroid-stimulating hormone and free thyroxine. […] Diagnosis is based on blood levels of decreased FT4, with a corresponding elevated thyrotropin (i.e., TSH) level in primary causes (thyroid source); the TSH level may be normal to low in secondary (pituitary source) or tertiary (hypothalamic source) causes. […] TSH elevation indicates hypothyroidism. Low-end normal TSH is 0.4 mIU per L. The upper-end normal range is from 4.0 to 4.5 mIU per L. FT4 level is used to distinguish clinical (low FT4) from subclinical (normal FT4) hypothyroidism.
#1 Thyroid Function Tests | American Thyroid Association
https://www.thyroid.org/thyroid-function-tests/
Blood tests to measure these hormones are readily available and widely used, but not all are useful in all situations. […] The best way to initially test thyroid function is to measure the TSH level in a blood sample. Changes in TSH can serve as an early warning system often occurring before the actual level of thyroid hormones in the body becomes too high or too low. A high TSH level indicates that the thyroid gland is not making enough thyroid hormone (primary hypothyroidism). […] The finding of an elevated TSH and low FT4 or FTI indicates primary hypothyroidism due to disease in the thyroid gland. […] A low TSH and low FT4 or FTI indicates hypothyroidism due to a problem involving the pituitary gland. […] T3 testing rarely is helpful in the hypothyroid patient, since it is the last test to become abnormal. Patients can be severely hypothyroid with a high TSH and low FT4 or FTI, but have a normal T3.
#1 Hypothyroidism – Wikipedia
https://en.wikipedia.org/wiki/Hypothyroidism
Hypothyroidism is an endocrine disease in which the thyroid gland does not produce enough thyroid hormones. The diagnosis of hypothyroidism, when suspected, can be confirmed with blood tests measuring thyroid-stimulating hormone (TSH) and thyroxine (T4) levels. Laboratory testing of thyroid stimulating hormone (TSH) levels in the blood is considered the best initial test for hypothyroidism; a second TSH level is often obtained several weeks later for confirmation. An elevated TSH level indicates that the thyroid gland is not producing enough thyroid hormone, and free T4 levels are then often obtained. A diagnosis of hypothyroidism without any lumps or masses felt within the thyroid gland does not require thyroid imaging; however, if the thyroid feels abnormal, diagnostic imaging is then recommended. If the TSH level is normal or low and serum free T4 levels are low, this is suggestive of central hypothyroidism. In overt primary hypothyroidism, TSH levels are high and T4 levels are low. Subclinical hypothyroidism is a biochemical diagnosis characterized by an elevated serum TSH level, but with a normal serum free thyroxine level.
#1 Hypothyroidism Information | Mount Sinai – New York
https://www.mountsinai.org/health-library/report/hypothyroidism
Hypothyroidism, also called underactive thyroid, is a condition in which the thyroid gland does not produce enough hormones. […] Hypothyroidism can cause serious complications if left untreated. Fortunately, it can be easily diagnosed with blood tests that measure levels of the pituitary thyroid-stimulating hormone (TSH) and the thyroid hormone thyroxine (T4). […] Hypothyroidism is classified as either overt or subclinical disease. That diagnosis is determined on the basis of the TSH laboratory blood tests: […] TSH levels over 10mU/L indicate overt hypothyroidism. People will usually need thyroxine (T4) replacement therapy. […] TSH levels between 4.5 and 10 mU/L indicate mildly underactive (subclinical) hypothyroidism. People should be retested every 6 to 12 months. The decision to treat is made on an individual basis.
#1
https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/diagnosis/
Less commonly, a thyroid antibody test may be recommended after a thyroid function test. This is to help diagnose or rule out autoimmune thyroid conditions, such as Hashimoto’s thyroiditis. A thyroid antibody test is only likely to be recommended if the GP suspects you have an autoimmune thyroid condition.
#1 Hypothyroidism: Diagnosis and Treatment | AAFP
https://www.aafp.org/pubs/afp/issues/2021/0515/p605.html
If the TSH level is high (greater than 4.5 mIU per L), a serum FT4 level should be obtained. A low FT4 level indicates clinical hypothyroidism, specifically autoimmune hypothyroidism (i.e., Hashimoto thyroiditis) if the TPO antibody test result is elevated). […] Subclinical hypothyroidism is a biochemical finding of an elevated TSH level with a normal FT4 level. This finding should initiate a TPO antibody test and an additional TSH test in six to 12 months. […] In nonpregnant patients with subclinical hypothyroidism, levothyroxine therapy should be considered when the TSH level is greater than 10 mIU per L or the TPO antibody level is elevated.
#1 Houston Thyroid & Endocrine Specialists – Diagnosis of Hypothyroidism
https://www.houstonendocrine.com/what-is-endocrinology/hypothyroidism/diagnosis-of-hypothyroidism
A low free thyroxine level along with a low or normal TSH level should generally lead to an evaluation for the possibility of failure of other endocrine systems that rely on normal pituitary function. […] Primary hypothyroidism, the cause of hypothyroidism in 99% of all patients, is associated with a significant increase in the basal blood TSH concentration. […] The presence of thyroid peroxidase antibodies (TPO antibodies) or thyroglobulin antibodies (TG antibodies) helps to distinguish among the causes of hypothyroidism and strongly suggests the presence of Hashimoto’s thyroid disease. […] This table, which is not exhaustive, reviews the possible diagnoses in patients with clinical low thyroid function, and it includes all causes of hypothyroidism. […] The likelihood of developing true hypothyroidism was defined as prescription of levothyroxine, or TSH above 4.50 mU/liter combined with free T4 below normal, in people without a history of hyperthyroidism.
#1 Hashimoto’s Thyroiditis
https://www.thyroidcancer.com/hashimotos-thyroiditis
Hashimotos thyroiditis is the most common cause of hypothyroidism in the US. […] The diagnosis of Hashimotos thyroiditis is made with a comprehensive analysis of the blood including thyroid stimulating hormone (TSH), Free T4 levels and Free T3 levels. In Hashimotos thyroiditis, the TSH level can be quite high consistent with a hypothyroid condition. […] The diagnosis of Hashimotos thyroiditis is made with the detection of a high TSH, low Free T4, and anti-thyroid antibodies. […] Hashimotos thyroiditis appears as a diffusely irregular gland with increased vascularity (new blood vessel flow) throughout the gland. […] Most thyroid nodules in Hashimotos thyroiditis are benign. Rarely, the FNA biopsy may come back as benign even though a diagnosis of a thyroid cancer is actually present.
#1 Hypothyroidism: Practice Essentials, Background, Pathophysiology
https://emedicine.medscape.com/article/122393-overview
Hypothyroidism is a common endocrine disorder resulting from deficiency of thyroid hormone. In the United States and other areas of adequate iodine intake, autoimmune thyroid disease (Hashimoto disease) is the most common cause of hypothyroidism; worldwide, iodine deficiency remains the foremost cause. […] Third-generation thyroid-stimulating hormone (TSH) assays are generally the most sensitive screening tool for primary hypothyroidism. If TSH levels are above the reference range, the next step is to measure free thyroxine (T4) or the free thyroxine index (FTI), which serves as a surrogate of the free hormone level. Routine measurement of triiodothyronine (T3) is not recommended. […] No universal screening recommendations exist for thyroid disease for adults. The American Thyroid Association recommends screening at age 35 years and every 5 years thereafter, with closer attention to patients who are at high risk, such as the following: Pregnant women, Women older than 60 years, Patients with type 1 diabetes or other autoimmune disease, Patients with a history of neck irradiation. […] For hypothyroidism, thyroid hormone is administered to supplement or replace endogenous production. In general, hypothyroidism can be adequately treated with a constant daily dose of levothyroxine (LT4).
#1 Hypothyroidism Investigation and management
https://www.racgp.org.au/afp/2012/august/hypothyroidism
Hypothyroidism is a common endocrine disorder that mainly affects women and the elderly. […] This article outlines the aetiology, clinical features, investigation and management of hypothyroidism. […] The initial screening for suspected hypothyroidism is thyroid stimulating hormone (TSH). A thyroid peroxidase antibody assay is the only test required to confirm the diagnosis of autoimmune thyroiditis. […] Initial screening is by measuring the thyroid stimulating hormone (TSH) level. If this is elevated, the TSH should be repeated within 28 weeks with a free T4 level to confirm the diagnosis. […] A positive thyroid peroxidase antibody assay confirms autoimmune thyroiditis as the cause. […] A diagnosis of hypothyroidism in itself is not an indication for thyroid imaging. […] Thyroid ultrasonography is only indicated to evaluate suspicious structural thyroid abnormalities (ie. palpable thyroid nodules).
#1 Hypothyroidism | Hashimoto’s Disease | MedlinePlus
https://medlineplus.gov/hypothyroidism.html
Hypothyroidism, or underactive thyroid, happens when your thyroid gland doesn’t make enough thyroid hormones to meet your body’s needs. […] Your health care provider may use many tools to make a diagnosis: A medical history, including asking about your symptoms, A physical exam, Thyroid tests, such as TSH, T3, T4, and thyroid antibody blood tests, Imaging tests, such as a thyroid scan, ultrasound, or radioactive iodine uptake test. A radioactive iodine uptake test measures how much radioactive iodine your thyroid takes up from your blood after you swallow a small amount of it.
#1 Thyroid Function Tests | American Thyroid Association
https://www.thyroid.org/thyroid-function-tests/
In many patients with hypothyroidism or hyperthyroidism, lymphocytes react against the thyroid (thyroid autoimmunity) and make antibodies against thyroid cell proteins. […] Measuring levels of thyroid antibodies may help diagnose the cause of the thyroid problem. […] While detecting antibodies is helpful in the initial diagnosis of hypothyroidism due to autoimmune thyroiditis, following their levels over time is not helpful in detecting the development of hypothyroidism or response to therapy. TSH and FT4 are what tell us about the actual thyroid function or levels. […] A very high RAIU is seen in individuals whose thyroid gland is overactive (hyperthyroidism), while a low RAIU is seen when the thyroid gland is underactive (hypothyroidism).
#1 Hypothyroidism – Causes, Symptoms, Treatment, Diagnosis – MedBroadcast.com
https://medbroadcast.com/condition/getcondition/hypothyroidism
Thyroid scans, using radioactive iodine or technetium, allow doctors to see the thyroid gland and identify areas that are less active. Thyroid ultrasound scans provide a detailed anatomic imaging of the gland, and can identify lesions (e.g. nodules, cysts), provide accurate size measurement, and show blood flow properties throughout the gland.
#1 Diagnosing Hypothyroidism | NYU Langone Health
https://nyulangone.org/conditions/hypothyroidism/diagnosis
Diagnosing Hypothyroidism […] To diagnose hypothyroidism, your doctor asks about your symptoms and your medical history. Your doctor also performs a physical exam to determine whether your thyroid is enlarged or feels tender or inflamed. A blood test confirms a diagnosis of hypothyroidism. […] The doctor takes a small sample of blood, which is analyzed in a laboratory to look for several markers, or indicators, of thyroid disease. The most sensitive of these is TSH. An elevated TSH level indicates that your thyroid has decreased function. […] If you are diagnosed with hypothyroidism, your doctor works with you to create a treatment program.
#1 Primary hypothyroidism – Symptoms, diagnosis and treatment | BMJ Best Practice US
https://bestpractice.bmj.com/topics/en-us/535
Primary hypothyroidism usually presents with nonspecific symptoms of fatigue, depression, constipation, and mild weight gain; physical exam may show dry skin, eyelid edema, and bradycardia. […] Elevated thyroid-stimulating hormone and low free thyroxine confirms diagnosis of overt primary hypothyroidism. […] Commonly, disease is subclinical with minimal elevation of thyroid-stimulating hormone and normal thyroxine. […] Hypothyroidism is a clinical state resulting from underproduction of the thyroid hormones thyroxine (T4) and triiodothyronine (T3). […] Overt primary hypothyroidism is defined as thyroid-stimulating hormone (TSH) concentrations above the reference range and free thyroxine concentrations below the reference range. […] Subclinical hypothyroidism is a state of mild thyroid failure, with normal levels of T4 and T3, and minimal elevation of TSH; it is usually asymptomatic. […] 1st tests to order: serum thyroid-stimulating hormone (TSH). […] Tests to consider: free serum thyroxine (T4), antithyroid peroxidase antibodies (anti-TPOAbs).
#1 Hypothyroidism | Cooper University Health Care
https://www.cooperhealth.org/services/hypothyroidism
Hypothyroidism is a condition marked by an underactive thyroid gland. […] Hypothyroidism means the thyroid is underactive, producing insufficient amounts of thyroid hormones. […] The symptoms of hypothyroidism may resemble other conditions or medical problems. Always consult your doctor for a diagnosis. […] Screening for hypothyroidism involves a blood test that measures thyroid hormone (thyroxine, or T4) and serum TSH (thyroid-stimulating hormone) levels. Hypothyroidism is often suspected when TSH levels are above normal and T4 levels are below normal. Always consult your doctor for a diagnosis. […] Anyone with symptoms of hypothyroidism, a history of hypothyroidism or with related conditions (for example, diabetes) should be screened.
#1 Hypothyroidism (underactive thyroid) – Diagnosis and treatment – Mayo Clinic
https://www.mayoclinic.org/diseases-conditions/hypothyroidism/diagnosis-treatment/drc-20350289
TSH tests also play an important role in managing hypothyroidism over time. They help your health care provider find and maintain the right dosage of medication for you. […] If you are diagnosed with subclinical hypothyroidism, talk about treatment with your health care provider. For a mild rise in TSH, thyroid hormone medicine may not be useful. If your TSH level is higher, but still in the subclinical range, thyroid hormones may improve some symptoms.
#1 Normal Thyroid Hormone Levels – Endocrine Surgery | UCLA Health
https://www.uclahealth.org/medical-services/surgery/endocrine-surgery/conditions-treated/thyroid/normal-thyroid-hormone-levels
Thyroid hormone treatment Levothyroxine is the standard of care in thyroid hormone replacement therapy and treatment of hypothyroidism. […] Monitoring thyroid levels on medication Correct dosing of thyroid hormone is usually assessed using the same tests for diagnosis of thyroid disease, including TSH and FT4.
#1
https://labtestsonline.org.uk/tests/thyroid-stimulating-hormone-tsh
To screen for and diagnose thyroid disorders; to monitor treatment of hypothyroidism and hyperthyroidism. […] The TSH test is often the first test for evaluating thyroid function and/or symptoms of hyper- or hypothyroidism. […] TSH testing is used to: screen newborns for an underactive thyroid, diagnose a thyroid disorder in a person with symptoms of thyroid disease, monitor thyroid replacement therapy in patients with hypothyroidism. […] A high TSH result often means an underactive thyroid gland caused by failure of the gland (hypothyroidism). […] A low TSH result can indicate an overactive thyroid gland (hyperthyroidism) or damage to the pituitary gland that prevents it from producing TSH. […] In patients treated for an underactive thyroid (hypothyroidism), TSH should be monitored every 3 months until the TSH has stabilized. […] Hypothyroidism is easily treated and controlled for in most people with thyroxine (T4) replacement in the form of a tablet. […] Yes, that is a good way to test for hypothyroidism during pregnancy, which is often overlooked.
#1 Become a member
https://www.btf-thyroid.org/thyroid-function-tests
The usual blood tests done for thyroid function are TSH, T4 and sometimes T3. […] If the TSH level is high and the FT4 result is low this suggests an underactive thyroid (hypothyroidism) that requires treatment. […] If you have been diagnosed with hypothyroidism you will start treatment with levothyroxine – a synthetic version of the thyroxine (T4) produced by the thyroid gland. […] Blood tests are currently the most accurate way to diagnose and manage thyroid disorders. […] It is important for your health that the TSH level is within the reference range. […] If you have a diagnosed thyroid disorder or have had previous treatment for an overactive thyroid, it is important to have a blood test every 12 months, or as advised by your doctor. […] Read about symptoms of an underactive thyroid (hypothyroidism) and how this thyroid disorder is diagnosed and managed.
#1 Why Thyroid Disorder Diagnosis Missed – Endocrinologist Perspective
https://www.endocrinemds.com/blogs/why-thyroid-disorder-may-be-missed/
The American Thyroid Association estimates that around 20 million Americans experience symptoms of thyroid disease; however, up to 60% of these people do not know they have a disorder. Undiagnosed thyroid conditions can put patients at risk of serious health complications, such as osteoporosis, cardiovascular disease, and infertility. […] One factor contributing to missed diagnoses of thyroid disorders is the failure of doctors to check thyroid levels during routine examinations. […] To ensure a thorough evaluation, requesting a complete thyroid panel that includes measurements of multiple hormones and thyroid antibodies like Thyroglobulin (Tg) is essential. […] Relying on outdated lab reference ranges for thyroid testing can lead to misinterpretation of results and potentially overlook underlying thyroid issues.
#1 Hypothyroidism – Thyroid UK
https://thyroiduk.org/if-you-are-hypothyroid/about-hypothyroidism/overview-of-hypothyroidism/
Hypothyroidism occurs when the thyroid gland produces less thyroid hormone than it should â which then causes the metabolism to run too slow. Hypothyroidism is also known as myxoedema or an underactive thyroid. […] Subclinical hypothyroidism (borderline hypothyroidism) is when patients have the symptoms but only one of the thyroid tests is abnormal â the thyroid-stimulating hormone (TSH) test. […] Blood tests should reveal whether the thyroid gland is underactive although some doctors may not do all the blood tests available. […] There are several thyroid tests that can be done to diagnose hypothyroidism: TSH (thyroid-stimulating hormone), FT4 (FreeT4), FT3 (FreeT3), TPO (thyroid peroxidase antibody), TgAb (thyroglobulin antibody). […] However, the TSH test is often the only test performed by doctors which means there is a possibility that autoimmune hypothyroidism and secondary hypothyroidism may be missed.
#1 Hypothyroidism (Underactive Thyroid): Symptoms & Treatment
https://my.clevelandclinic.org/health/diseases/12120-hypothyroidism
You cant prevent hypothyroidism. If you develop symptoms like the ones mentioned above, let your healthcare provider know right away. Early diagnosis and treatment are the best ways to reduce your risk of complications and live a healthy life. […] Currently, theres no cure for hypothyroidism. But you can successfully manage the condition with hormone replacement therapy. […] If you develop hypothyroidism symptoms like weight gain, dry skin or fatigue, let your healthcare provider know. They may want to run tests to rule out other conditions. […] Without treatment, hypothyroidism can become a serious and life-threatening medical condition.
#1 Hypothyroidism (underactive thyroid) – Symptoms and causes – Mayo Clinic
https://www.mayoclinic.org/diseases-conditions/hypothyroidism/symptoms-causes/syc-20350284
Hypothyroidism happens when the thyroid gland doesn’t make enough thyroid hormone. This condition also is called underactive thyroid. […] Blood tests are used to diagnose hypothyroidism. Treatment with thyroid hormone medicine usually is simple, safe and effective once you and your health care provider find the right dosage for you. […] See your health care provider if you’re feeling tired for no reason or if you have other symptoms of hypothyroidism. […] Hypothyroidism happens when the thyroid gland doesn’t make enough hormones. […] Hypothyroidism that isn’t treated can lead to other health problems, including: […] Hypothyroidism may cause the thyroid gland to become larger. This condition is called a goiter. […] Hypothyroidism can lead to a higher risk of heart disease and heart failure.
#1 Hypothyroidism (Underactive Thyroid) – NIDDK
https://www.niddk.nih.gov/health-information/endocrine-diseases/hypothyroidism
How do doctors diagnose hypothyroidism? Your doctor will take your medical history and perform a physical exam. A hypothyroidism diagnosis cant be based on symptoms alone because many of its symptoms are the same as those of other diseases. Thats why your doctor may use several thyroid blood tests and imaging tests to confirm the diagnosis and find its cause. […] Hypothyroidism is treated by replacing the hormones that your own thyroid can no longer make. You will take levothyroxine, a thyroid hormone medicine identical to a hormone a healthy thyroid makes. Usually prescribed in pill form, this medicine is also available as a liquid and as a soft gel capsule. These newer formulas may help people with digestive problems to absorb the thyroid hormone. Your doctor may recommend taking the medicine in the morning before eating.
#2 Hypothyroidism (Underactive Thyroid): Symptoms & Treatment
https://my.clevelandclinic.org/health/diseases/12120-hypothyroidism
Hypothyroidism is when your thyroid gland doesnt make and release enough hormone into your bloodstream. […] Although weight gain and fatigue arent specific to hypothyroidism, a simple blood test can help your healthcare provider check for this condition. […] Healthcare providers usually run thyroid tests to get an accurate hypothyroidism diagnosis. This is because an underactive thyroid can cause symptoms that mimic other, unrelated health conditions. Thyroid blood tests measure the level of thyroid-stimulating hormone (TSH) in your blood as well as the levels for each thyroid hormone (T3 and T4). […] If you develop any signs of hypothyroidism, let your healthcare provider know. They can run tests to confirm a diagnosis. […] The most common hypothyroidism treatment is hormone replacement therapy. Levothyroxine (Synthroid, Levo-T) is a medication that replaces the hormones that your thyroid cant make naturally.
#2
https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/
An underactive thyroid gland (hypothyroidism) is where your thyroid gland does not produce enough hormones. […] The only accurate way of finding out whether you have a thyroid problem is to have a thyroid function test, where a sample of blood is tested to measure your hormone levels.
#2 Patient Journey Thyroid – Diagnosis | American Association of Clinical Endocrinology
https://www.aace.com/patient-journey/thyroid/diagnosis
How are thyroid disorders diagnosed? […] An underactive thyroid, or hypothyroidism, occurs when the thyroid gland creates less than the normal amount of thyroid hormone. […] Hypothyroidism usually is a permanent condition that can be treated. […] A primary care provider may make the diagnosis of hypothyroidism, but assistance is often needed from an endocrinologist, a specially trained health care professional who is qualified to diagnose and treat hormone-related conditions, including diseases related to the thyroid gland. […] Hypothyroidism testing may include: TSH (thyroid-stimulating hormone or thyrotropin): An increased TSH level in the blood is the most accurate indicator of hypothyroidism. […] Increased TSH level in the blood is the most accurate indicator of hypothyroidism. […] A low level of free T4 is consistent with thyroid hormone deficiency.
#2 Normal Thyroid Hormone Levels – Endocrine Surgery | UCLA Health
https://www.uclahealth.org/medical-services/surgery/endocrine-surgery/conditions-treated/thyroid/normal-thyroid-hormone-levels
A high TSH level indicates that the thyroid gland is not making enough thyroid hormone (primary hypothyroidism). […] A high TSH and low thyroid hormone level (e.g. low FT4) can indicate primary hypothyroidism. Primary hypothyroidism occurs when the thyroid gland makes too little thyroid hormone. Symptoms of hypothyroidism can include feeling cold, constipation, weight gain, slowed thinking, and decreased energy. […] Early or mild hypothyroidism may present as a persistently high TSH and a normal FT4 hormone level. This pattern is called subclinical hypothyroidism and your doctor may recommend treatment. […] Central hypothyroidism is treated with thyroid hormone replacement. Importantly, adequacy of thyroid replacement in central hyperthyroidism is assessed with FT4 and Total T4 tests not TSH as in primary hyperthyroidism, and deficiency in stress hormone cortisol should be assessed before starting thyroid treatment to prevent an adrenal crisis.
#2 Hypothyroidism: Diagnosis and Treatment | AAFP
https://www.aafp.org/pubs/afp/issues/2021/0515/p605.html
If the TSH level is high (greater than 4.5 mIU per L), a serum FT4 level should be obtained. A low FT4 level indicates clinical hypothyroidism, specifically autoimmune hypothyroidism (i.e., Hashimoto thyroiditis) if the TPO antibody test result is elevated). […] Subclinical hypothyroidism is a biochemical finding of an elevated TSH level with a normal FT4 level. This finding should initiate a TPO antibody test and an additional TSH test in six to 12 months. […] In nonpregnant patients with subclinical hypothyroidism, levothyroxine therapy should be considered when the TSH level is greater than 10 mIU per L or the TPO antibody level is elevated.
#2 Hypothyroidism (underactive thyroid) – Diagnosis and treatment – Mayo Clinic
https://www.mayoclinic.org/diseases-conditions/hypothyroidism/diagnosis-treatment/drc-20350289
The symptoms of hypothyroidism can be different from person to person. And they often look like symptoms of other health problems. Because of that, a diagnosis of hypothyroidism doesn’t rely on symptoms alone. It’s usually based on the results of blood tests. […] The first blood test typically done to diagnose hypothyroidism measures the level of thyroid-stimulating hormone (TSH) in the blood. If it’s high, the test is done again, along with a blood test for the thyroid hormone T-4. If the results show that TSH is high and T-4 is low, then the diagnosis is hypothyroidism. In some cases, the thyroid hormone T-3 may be measured as well. […] If the second test shows high TSH but T-4 and T-3 are in the standard range, then the diagnosis is a condition called subclinical hypothyroidism. It usually doesn’t cause any noticeable symptoms.
#2 Hypothyroidism Information | Mount Sinai – New York
https://www.mountsinai.org/health-library/report/hypothyroidism
Hypothyroidism, also called underactive thyroid, is a condition in which the thyroid gland does not produce enough hormones. […] Hypothyroidism can cause serious complications if left untreated. Fortunately, it can be easily diagnosed with blood tests that measure levels of the pituitary thyroid-stimulating hormone (TSH) and the thyroid hormone thyroxine (T4). […] Hypothyroidism is classified as either overt or subclinical disease. That diagnosis is determined on the basis of the TSH laboratory blood tests: […] TSH levels over 10mU/L indicate overt hypothyroidism. People will usually need thyroxine (T4) replacement therapy. […] TSH levels between 4.5 and 10 mU/L indicate mildly underactive (subclinical) hypothyroidism. People should be retested every 6 to 12 months. The decision to treat is made on an individual basis.
#2 Hypothyroidism – Endocrine and Metabolic Disorders – Merck Manual Professional Edition
https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/thyroid-disorders/hypothyroidism
Hypothyroidism is thyroid hormone deficiency. […] Diagnosis is with thyroid function tests. […] Serum thyroid-stimulating hormone measurement is the most sensitive test for diagnosing hypothyroidism. In primary hypothyroidism, there is decreased feedback inhibition of the intact pituitary, and serum TSH is always elevated, whereas serum free T4 is low. In secondary hypothyroidism, free T4 and serum TSH are low (sometimes TSH is normal but with decreased bioactivity). […] Diagnose primary or secondary hypothyroidism by testing serum TSH and T4. In primary hypothyroidism, TSH is elevated and T4 is low; in secondary hypothyroidism, both TSH and T4 are low.
#2 Borderline Hypothyroidism: Symptoms, Treatment and More
https://www.health.com/condition/thyroid/treatment-for-borderline-underactive-thyroid
Subclinical, or „borderline,” hypothyroidism is an early form of hypothyroidism. This condition causes an underactive thyroid, which results in high thyroid-stimulating hormone (TSH) levels. […] A healthcare provider can diagnose borderline hypothyroidism using a blood test to check TSH levels. […] The endocrinologist will also order a blood test to measure the levels of two hormones: T4 and TSH. High levels of TSH, or above 4.0 to 4.5 milli-international units per liter (mIU/L), can indicate an underactive thyroid. T4 levels will be relatively normal in the case of borderline hypothyroidism. […] This blood test can usually confirm borderline hypothyroidism. […] The goal of treatment is to closely replicate normal thyroid functioning. You’ll need to take medication to replace the amount of thyroid hormone the gland can’t make if you have hypothyroidism.
#2 Thyroid Function Tests | American Thyroid Association
https://www.thyroid.org/thyroid-function-tests/
In many patients with hypothyroidism or hyperthyroidism, lymphocytes react against the thyroid (thyroid autoimmunity) and make antibodies against thyroid cell proteins. […] Measuring levels of thyroid antibodies may help diagnose the cause of the thyroid problem. […] While detecting antibodies is helpful in the initial diagnosis of hypothyroidism due to autoimmune thyroiditis, following their levels over time is not helpful in detecting the development of hypothyroidism or response to therapy. TSH and FT4 are what tell us about the actual thyroid function or levels. […] A very high RAIU is seen in individuals whose thyroid gland is overactive (hyperthyroidism), while a low RAIU is seen when the thyroid gland is underactive (hypothyroidism).
#2 Tests to diagnose Hypothyroidism | Hospital ClÃnic Barcelona
https://www.clinicbarcelona.org/en/assistance/diseases/hypothyroidism/diagnosis
Blood tests. The most sensitive test is the measurement of thyrotropin or thyroid-stimulating hormone (TSH). High TSH levels generally indicate hypothyroidism. The next test is to determine the active circulating thyroxine, free thyroxine (T4L), which is low in hypothyroidism, although in some cases it may be normal and indicate non-symptomatic hypothyroidism. If the levels of TSH and T4L are low it means that the thyroid is functioning correctly and the hypothyroidism is caused by a lack of TSH. This is because when the pituitary gland detects low levels of T4L, it is not able to boost the release of TSH, so it does not stimulate the thyroid to produce more hormones, causing hypothyroidism in the patient. […] To determine whether the disease is an autoimmune disease, caused by the immune system overreacting against the thyroid, the presence of „anti-thyroid” antibodies is tested: anti-peroxidase (anti-TPO) and anti-thyroglobulin (anti-TG) antibodies. […] Imaging tests. These are usually used to study the shape of any nodules or goitre associated with hypothyroidism, but not for hypothyroidism itself.
#2 Thyroid Tests – NIDDK
https://www.niddk.nih.gov/health-information/diagnostic-tests/thyroid
Health care professionals use thyroid tests to check how well your thyroid is working and to find the cause of problems such as hyperthyroidism or hypothyroidism. […] Thyroid tests help health care professionals diagnose thyroid diseases such as hypothyroidism when thyroid hormones levels are too low. […] A high TSH level most often means you have hypothyroidism, or an underactive thyroid. This means that your thyroid isn’t making enough hormone. […] A low level of T4 may mean you have hypothyroidism. […] Measuring levels of thyroid antibodies may help diagnose an autoimmune thyroid disorder such as Hashimoto’s diseaseâthe most common cause of hypothyroidism. […] If your thyroid collects a large amount of radioactive iodine, you may have Graves disease, or one or more nodules that make too much thyroid hormone.
#2 Underactive thyroid | NHS inform
https://www.nhsinform.scot/illnesses-and-conditions/glands/underactive-thyroid/
Your GP may recommend that you have a repeat blood test every so often to see whether you eventually develop an underactive thyroid. […] An underactive thyroid (hypothyroidism) is usually treated by taking daily hormone replacement tablets called levothyroxine. […] Levothyroxine replaces the thyroxine hormone, which your thyroid doesnt make enough of. […] If blood tests suggest you may have an underactive thyroid, but you dont have any symptoms or theyre very mild, you may not need any treatment. […] Several complications can occur if you have an underactive thyroid that isnt treated. […] If you have an untreated underactive thyroid, your risk of developing cardiovascular disease is increased. […] A goitre is an abnormal swelling of the thyroid gland that causes a lump to form in the throat. […] If an underactive thyroid isnt treated during pregnancy, theres a risk of problems occurring. […] In very rare cases, a severe underactive thyroid may lead to a life-threatening condition called myxoedema coma.
#2 Borderline Hypothyroidism: Symptoms, Treatment and More
https://www.health.com/condition/thyroid/treatment-for-borderline-underactive-thyroid
The American Thyroid Association (ATA) guidelines recommend levothyroxine therapy at TSH levels of 10 mIU/L or less if you meet any of the following criteria: There are clear symptoms of hypothyroidism, There’s evidence of atherosclerotic heart disease (hardening of the arteries) or heart failure, You have positive thyroid autoantibodies. […] Borderline hypothyroidism can progress to overt hypothyroidism, so some healthcare providers say it’s useful to take medication. […] A healthcare provider can help you weigh the costs and benefits of treatment in your case.
#2 Thyroid: Function, Problems, Location
https://www.health.com/thyroid-disease-diagnosis-7109384
Hypothyroidism, or underactive thyroid, is when the thyroid doesn’t make enough hormones. […] Without enough thyroid hormone, many of your body functions may slow down. You may gain weight, be fatigued, and have thinning hair. […] The most common cause of hypothyroidism is Hashimoto’s disease, an autoimmune condition in which your immune cells destroy the thyroid gland. […] Hypothyroidism is more common among women and those older than 60. Other risk factors include having a personal or family history of a thyroid problem. […] Hypothyroidism is treated through medication. Symptoms can sometimes be improved by changes in diet and lifestyle as well. […] Your healthcare provider may use the following tools to figure out if you have a thyroid issue and, if so, what the issue is: Blood tests such as T3, T4, thyroid stimulating hormone (TSH), and thyroid antibody levels to check your thyroid function.
#2 Hypothyroidism: causes, diagnosis and treatment – The Pharmaceutical Journal
https://pharmaceutical-journal.com/article/ld/hypothyroidism-causes-diagnosis-and-treatment
Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormone, often requiring pharmacological management. […] Pharmacists should be able to recognise and treat the condition as they may provide direct patient care in both primary and secondary settings. […] Recognise the symptoms of hypothyroidism and understand the different biochemical tests that are used to diagnose the condition. […] Diagnosis of hypothyroidism is based on patientsâ presenting symptoms, alongside biochemical testing of TSH and free T4 levels. […] Testing of the âfreeâ hormone ideally provides a more reliable diagnostic result, as it only represents hormone available for action, as opposed to inactive protein-bound hormone. […] National Institute for Health and Care Excellence (NICE) guidance recommends that all patients presenting with new-onset atrial fibrillation, type 1 diabetes or other autoimmune disorders should be offered biochemical testing for thyroid dysfunction and that it should be considered in patients with unexplained depression and anxiety.
#2
https://www2.hse.ie/conditions/underactive-thyroid-hypothyroidism/
An underactive thyroid gland (hypothyroidism) means your thyroid gland is not producing enough hormones. […] The only accurate way of finding out if you have a thyroid problem is to have a thyroid function test. This is where a sample of blood is tested to measure your hormone levels. […] Treatment for an underactive thyroid involves taking daily hormone replacement tablets. […] You’ll have regular blood tests until the correct dose of levothyroxine is reached. This can take a little while to get right. When you’re taking the correct dose, you’ll have a blood test once a year to check your hormone levels. […] If an underactive thyroid is not treated, it can lead to complications.
#2 Hypothyroidism | American Thyroid Association
https://www.thyroid.org/hypothyroidism/
Hypothyroidism is an underactive thyroid gland. Hypothyroidism means that the thyroid gland cant make enough thyroid hormone to keep the body running normally. […] Because the symptoms are so variable and nonspecific, the only way to know for sure whether you have hypothyroidism is with a simple blood test for TSH. […] The correct diagnosis of hypothyroidism depends on the following: Symptoms. Hypothyroidism doesnt have any characteristic symptoms. There are no symptoms that people with hypothyroidism always have and many symptoms of hypothyroidism can occur in people with other diseases. […] Blood tests. There are two blood tests that are used in the diagnosis of hypothyroidism. TSH (thyroid-stimulating hormone) test. This is the most important and sensitive test for hypothyroidism. It measures how much of the thyroid hormone thyroxine (T4) the thyroid gland is being asked to make. An abnormally high TSH means hypothyroidism: the thyroid gland is being asked to make more T4 because there isnt enough T4 in the blood.
#2 Hypothyroidism (underactive thyroid) – Symptoms and causes – Mayo Clinic
https://www.mayoclinic.org/diseases-conditions/hypothyroidism/symptoms-causes/syc-20350284
Hypothyroidism that goes without treatment for a long time can damage the peripheral nerves. […] Low levels of thyroid hormone can interfere with ovulation, which can limit fertility. […] Babies born to people with untreated thyroid disease may have a higher risk of birth defects compared with babies born to mothers who do not have thyroid disease. […] This rare, life-threatening condition can happen when hypothyroidism goes without treatment for a long time.