Chronic thyroiditis (Hashimoto disease)
Hashimoto thyroiditis; Chronic lymphocytic thyroiditis; Autoimmune thyroiditis; Chronic autoimmune thyroiditis; Lymphadenoid goiter - Hashimoto; Hypothyroidism - Hashimoto; Type 2 polyglandular autoimmune syndrome - Hashimoto; PGA II - HashimotoChronic thyroiditis is caused by a reaction of the immune system against the thyroid gland. It often results in reduced thyroid function (hypothyroidism).
Hypothyroidism
Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone. This condition is often called underactive thyroid....

The disorder is also called Hashimoto disease.
The thyroid gland is located in the neck, just above where your collarbones meet in the middle.
Causes
Hashimoto disease is a common thyroid gland disorder. It can occur at any age, but is most often seen in middle-aged women. It is caused by a reaction of the immune system against the thyroid gland.
Reaction of the immune system
An autoimmune disorder occurs when the body's immune system attacks and destroys healthy body tissue by mistake. There are more than 80 types of aut...

The disease begins slowly. It may take months or even years for the condition to be detected and for thyroid hormone levels to become lower than normal. Hashimoto disease is most common in people with a family history of thyroid disease.
In rare cases, the disease may be related to other hormone problems caused by the immune system. It can occur with poor adrenal function and type 1 diabetes. In these cases, the condition is called type 2 polyglandular autoimmune syndrome (PGA II).
Rarely (usually in children), Hashimoto disease occurs as part of a condition called type 1 polyglandular autoimmune syndrome (PGA I), along with:
- Poor function of the adrenal glands
- Fungal infections of the mouth and nails
- Underactive parathyroid gland
Symptoms
Symptoms of Hashimoto disease may include any of the following:
- Constipation
- Difficulty concentrating or thinking
- Dry skin
- Enlarged neck or presence of goiter, which may be the only early symptom
Goiter
A simple goiter is an enlargement of the thyroid gland. It is usually not a tumor or cancer.
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Fatigue
Fatigue is a feeling of weariness, tiredness, or lack of energy.
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- Heavy or irregular periods
- Intolerance to cold
Intolerance to cold
Cold intolerance is an abnormal sensitivity to a cold environment or cold temperatures.
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- Small or shrunken thyroid gland (late in the disease)
Exams and Tests
Laboratory tests to determine thyroid function include:
- Free T4 test
T4 test
T4 (thyroxine) is the main hormone produced by the thyroid gland. A laboratory test can be done to measure the amount of free T4 in your blood. Fre...
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Serum TSH
A TSH test measures the amount of thyroid stimulating hormone (TSH) in your blood. TSH is produced by the pituitary gland. It prompts the thyroid g...
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Total T3
T3
Triiodothyronine (T3) is a thyroid hormone. It plays an important role in the body's control of metabolism (the many processes that control the rate...
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Thyroid autoantibodies
Thyroid peroxidase is a type of protein (called an enzyme) that cells in the thyroid gland use to make thyroid hormone. If these enzymes leak out in...
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Imaging studies and fine needle biopsy are generally not needed to diagnose Hashimoto thyroiditis.
This disease may also change the results of the following tests:
- Complete blood count
- Serum prolactin
- Serum sodium
- Total cholesterol
Untreated hypothyroidism can change how your body uses medicines that you may take for other conditions, such as epilepsy. You'll likely need to have regular blood tests to check the levels of the medicines in your body.
Treatment
If you have findings of an underactive thyroid, you may receive thyroid replacement medicine.
Not everyone with thyroiditis or goiter has low levels of thyroid hormone. You may just need regular follow-up by a health care provider.
Outlook (Prognosis)
The disease stays stable for years. If it does slowly progress to thyroid hormone deficiency (hypothyroidism), it can be treated with hormone replacement therapy.
Possible Complications
This condition can occur with other autoimmune disorders. In rare cases, thyroid cancer or thyroid lymphoma may develop.
Severe untreated hypothyroidism can lead to a change in consciousness, coma, and death. This usually occurs if people get an infection, are injured, or take medicines, such as opioids.
When to Contact a Medical Professional
Call your provider if you develop symptoms of chronic thyroiditis or hypothyroidism.
Prevention
There is no known way to prevent this disorder. Being aware of risk factors may allow earlier diagnosis and treatment.
References
Brent GA, Weetman AP. Hypothyroidism and thyroiditis. In: Melmed S, Auchus RJ, Golfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 13.
Jonklaas J, Bianco AC, Bauer AJ, et al. Guidelines for the treatment of hypothyroidism: prepared by the American Thyroid Association task force on thyroid hormone replacement. Thyroid. 2014;24(12):1670-1751. PMID: 25266247 pubmed.ncbi.nlm.nih.gov/25266247/.
Lakis ME, Wiseman D, Kebebew E. Management of thyroiditis. In: Cameron AM, Cameron JL, eds. Current Surgical Therapy. 13th ed. Philadelphia, PA: Elsevier; 2020:764-767.
Marcdante KJ, Kliegman RM. Thyroid disease. In: Marcdante KJ, Kliegman RM, eds. Nelson Essentials of Pediatrics. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 175.
Hypothyroidism
Animation
Endocrine glands - illustration
Endocrine glands release hormones (chemical messengers) into the bloodstream to be transported to various organs and tissues throughout the body. For instance, the pancreas secretes insulin, which allows the body to regulate levels of sugar in the blood. The thyroid gets instructions from the pituitary to secrete hormones which determine the rate of metabolism in the body (the more hormone in the bloodstream, the faster the chemical activity; the less hormone, the slower the activity).
Endocrine glands
illustration
Thyroid enlargement - scintiscan - illustration
This image shows the enlargement of the thyroid gland and extension down behind the breastbone (retrosternal space). The image, called a scintiscan, was generated using a radioactive isotope.
Thyroid enlargement - scintiscan
illustration
Hashimoto's disease (chronic thyroiditis) - illustration
Chronic thyroiditis (Hashimoto's disease) is a slowly developing persistent inflammation of the thyroid which frequently leads to hypothyroidism, a decreased function of the thyroid gland. Middle-aged women are most commonly affected.
Hashimoto's disease (chronic thyroiditis)
illustration
Thyroid gland - illustration
The thyroid gland, a part of the endocrine (hormone) system, plays a major role in regulating the body's metabolism.
Thyroid gland
illustration
Endocrine glands - illustration
Endocrine glands release hormones (chemical messengers) into the bloodstream to be transported to various organs and tissues throughout the body. For instance, the pancreas secretes insulin, which allows the body to regulate levels of sugar in the blood. The thyroid gets instructions from the pituitary to secrete hormones which determine the rate of metabolism in the body (the more hormone in the bloodstream, the faster the chemical activity; the less hormone, the slower the activity).
Endocrine glands
illustration
Thyroid enlargement - scintiscan - illustration
This image shows the enlargement of the thyroid gland and extension down behind the breastbone (retrosternal space). The image, called a scintiscan, was generated using a radioactive isotope.
Thyroid enlargement - scintiscan
illustration
Hashimoto's disease (chronic thyroiditis) - illustration
Chronic thyroiditis (Hashimoto's disease) is a slowly developing persistent inflammation of the thyroid which frequently leads to hypothyroidism, a decreased function of the thyroid gland. Middle-aged women are most commonly affected.
Hashimoto's disease (chronic thyroiditis)
illustration
Thyroid gland - illustration
The thyroid gland, a part of the endocrine (hormone) system, plays a major role in regulating the body's metabolism.
Thyroid gland
illustration
Review Date: 2/1/2022
Reviewed By: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.