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Hashimoto Thyroiditis

(Autoimmune Thyroiditis; Chronic Lymphocytic Thyroiditis)


Jerome M. Hershman

, MD, MS, David Geffen School of Medicine at UCLA

Last full review/revision Sep 2020| Content last modified Sep 2020
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Hashimoto thyroiditis is chronic autoimmune inflammation of the thyroid with lymphocytic infiltration. Findings include painless thyroid enlargement and symptoms of hypothyroidism. Diagnosis involves demonstration of high titers of thyroid peroxidase antibodies. Lifelong L-thyroxine replacement is typically required.

Hashimoto thyroiditis, like Graves disease Hyperthyroidism is characterized by hypermetabolism and elevated serum levels of free thyroid hormones. Symptoms are many and include tachycardia, fatigue, weight loss, nervousness, and tremor... read more , is sometimes associated with other autoimmune disorders, including Addison disease Addison Disease Addison disease is an insidious, usually progressive hypofunctioning of the adrenal cortex. It causes various symptoms, including hypotension and hyperpigmentation, and can lead to adrenal crisis... read more Addison Disease (adrenal insufficiency), type 1 diabetes mellitus Diabetes Mellitus (DM) Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more , hypoparathyroidism Hypoparathyroidism Hypocalcemia is a total serum calcium concentration 8.8 mg/dL ( 2.20 mmol/L) in the presence of normal plasma protein concentrations or a serum ionized calcium concentration 4.7 mg/dL ( 1.17... read more , vitiligo Vitiligo Vitiligo is a loss of skin melanocytes that causes areas of skin depigmentation of varying sizes. Cause is unknown, but genetic and autoimmune factors are likely. Diagnosis is usually clear... read more Vitiligo , premature graying of hair, pernicious anemia, connective tissue disorders (eg, rheumatoid arthritis Rheumatoid Arthritis (RA) Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that primarily involves the joints. RA causes damage mediated by cytokines, chemokines, and metalloproteases. Characteristically... read more Rheumatoid Arthritis (RA) , systemic lupus erythematosus Systemic Lupus Erythematosus (SLE) Systemic lupus erythematosus is a chronic, multisystem, inflammatory disorder of autoimmune etiology, occurring predominantly in young women. Common manifestations may include arthralgias and... read more Systemic Lupus Erythematosus (SLE) , Sjögren syndrome Sjögren Syndrome Sjögren syndrome is a relatively common chronic, autoimmune, systemic, inflammatory disorder of unknown cause. It is characterized by dryness of the mouth, eyes, and other mucous membranes due... read more Sjögren Syndrome ), celiac disease Celiac Disease Celiac disease is an immunologically mediated disease in genetically susceptible people caused by intolerance to gluten, resulting in mucosal inflammation and villous atrophy, which causes malabsorption... read more Celiac Disease , and type 2 polyglandular deficiency syndrome Type 2 polyglandular deficiency Polyglandular deficiency syndromes (PDS) are characterized by sequential or simultaneous deficiencies in the function of several endocrine glands that have a common cause. Etiology is most often... read more (Schmidt syndrome—a combination of Addison disease with hypothyroidism secondary to Hashimoto thyroiditis and/or type 1 diabetes mellitus). There may be an increased incidence of thyroid tumors, rarely thyroid lymphoma. Pathologically, there is extensive infiltration of lymphocytes with lymphoid follicles and scarring.

Symptoms and Signs of Hashimoto Thyroiditis

Diagnosis of Hashimoto Thyroiditis

  • Thyroxine (T4)

  • Thyroid-stimulating hormone (TSH)

  • Thyroid autoantibodies

  • Thyroid ultrasonography

Testing Laboratory Testing of Thyroid Function The thyroid gland, located in the anterior neck just below the cricoid cartilage, consists of 2 lobes connected by an isthmus. Follicular cells in the gland produce the 2 main thyroid hormones... read more consists of measuring T4, TSH, and thyroid autoantibodies. Early in the disease, T4 and TSH levels are normal and there are high levels of thyroid peroxidase antibodies and, less commonly, of antithyroglobulin antibodies.

Thyroid ultrasonography should be done if there are palpable nodules. Ultrasonography often reveals that the thyroid tissue has a heterogeneous, hypoechoic echotexture with septations that form hypoechoic micronodules.

Testing for other autoimmune disorders is warranted only when clinical manifestations are present.

Treatment of Hashimoto Thyroiditis

  • Thyroid hormone replacement

Occasionally, hypothyroidism is transient, but most patients require lifelong thyroid hormone replacement, typically L-thyroxine (levothyroxine) 75 to 150 mcg orally once a day.

Key Points

  • Hashimoto thyroiditis is autoimmune inflammation of the thyroid.

  • Patients sometimes have other autoimmune disorders.

  • Thyroxine (T4) and thyroid-stimulating hormone (TSH) levels initially are normal, but later, T4 declines and TSH rises, and most patients become clinically hypothyroid.

  • There are high levels of thyroid peroxidase antibodies and, less commonly, of antithyroglobulin antibodies.

  • Lifelong thyroid hormone replacement is typically needed.

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