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Hashimoto Thyroiditis

(Autoimmune Thyroiditis; Chronic Lymphocytic Thyroiditis)


Laura Boucai

, MD, Weill Cornell Medical College

Reviewed/Revised Feb 2024

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 levothyroxine replacement is typically required for patients who develop hypothyroidism.

Hashimoto thyroiditis, like Graves disease Etiology Etiology , 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... 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 Megaloblastic Macrocytic Anemias Megaloblastic anemias result most often from deficiencies of vitamin B12 and folate. Ineffective hematopoiesis affects all cell lines but particularly red blood cells. Diagnosis is usually based... read more Megaloblastic Macrocytic Anemias , systemic rheumatic diseases (eg, rheumatoid arthritis Rheumatoid Arthritis (RA) Rheumatoid arthritis is a chronic systemic autoimmune disease that primarily involves the joints. Rheumatoid arthritis causes damage mediated by cytokines, chemokines, and metalloproteases.... 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 ... 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 are characterized by sequential or concurrent deficiencies in the function of several endocrine glands that have a common cause. Etiology is most often autoimmune... 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

Patients have painless enlargement of the thyroid or fullness in the throat. Examination reveals a nontender goiter that is smooth or nodular, firm, and more rubbery than the normal thyroid. Many patients present with symptoms of hypothyroidism Symptoms and Signs Hypothyroidism is thyroid hormone deficiency. Symptoms include cold intolerance, fatigue, and weight gain. Signs may include a typical facial appearance, hoarse slow speech, and dry skin. Diagnosis... read more Symptoms and Signs (eg, fatigue, cold intolerance, weight gain), but some present with hyperthyroidism Hyperthyroidism Hyperthyroidism is characterized by hypermetabolism and elevated serum levels of free thyroid hormones. Symptoms include palpitations, fatigue, weight loss, heat intolerance, anxiety, and tremor... read more Hyperthyroidism (eg, heat intolerance, weight loss) that may be due to release of thyroid hormones during the inflammatory phase of thyroiditis or from co-existence of Graves disease and Hashimoto thyroiditis in the gland.

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 (see table ).

Thyroid ultrasonography should be done if there are palpable nodules Approach to the Patient With a Thyroid Nodule Thyroid nodules are benign or malignant growths within the thyroid gland. They are common, increasingly so with increasing age. (See also Overview of Thyroid Function.) The reported incidence... read more . Ultrasonography often reveals that the thyroid tissue has a heterogeneous, hypoechoic echotexture with septations that form hypoechoic micronodules, and there may be reduced vascularity of the gland.

Testing for other autoimmune disorders is warranted only when clinical manifestations are present or when there is a strong family history of Hashimoto thyroiditis or Graves disease Etiology Etiology associated with autoimmune polyglandular deficiency syndrome.

Treatment of Hashimoto Thyroiditis

  • Thyroid hormone replacement

Occasionally, hypothyroidism is transient, but most patients require lifelong thyroid hormone replacement, typically 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 patients may become clinically hypothyroid.

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

  • Lifelong thyroid hormone replacement is typically needed.

Drugs Mentioned In This Article

Drug Name Select Trade
Ermeza, Estre , Euthyrox, Levo-T, Levothroid, Levoxyl, Synthroid, Thyquidity, Thyro-Tabs, TIROSINT, TIROSINT-SOL, Unithroid
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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