- Clinical science
Hashimoto disease is the most common form of autoimmune thyroiditis and the leading cause of hypothyroidism in the United States. Although currently thought to be due to chronic autoimmune-mediated lymphocytic inflammation of the thyroid tissue, the exact pathophysiology remains unclear. Patients are initially asymptomatic or hyperthyroid, progressing to hypothyroidism as the organ parenchyma is destroyed. Diagnosis is based on a combination of specific antibodies, thyroid function tests, and sonography of the thyroid. Treatment involves lifelong hormone replacement therapy with levothyroxine (L-thyroxine).
- Prevalence: : 5% in the US; Hashimoto disease is the most common form of thyroiditis and the most frequent cause of hypothyroidism in the US.
- Sex: ♀ > ♂ (7:1)
- Age of onset: occurs in all age groups; , particularly in women aged 30–50 years
Epidemiological data refers to the US, unless otherwise specified.
- Unknown etiology: Genetic and environmental factors likely play a role.
- Immunological mechanisms
- Associations: often associated with Non-Hodgkin lymphoma or autoimmune diseases
- Certain factors may precipitate Hashimoto's thyroiditis (e.g., thyroid injury, stress or iodine), however, most remain hypothetical.
- Thyroid metabolism
- Antibody detection
Other laboratory tests
- Lipid profile: ↑ LDL and ↓ HDL
- CBC: ↓ Hb
- Fine-needle aspiration: : to exclude malignancy or lymphoma, especially in cases of rapid goiter growth
- Radioactive iodine uptake test (RIUT): Radioactive iodine uptake is variable, often patchy and irregular with either an increase or decrease in 99mTc uptake. There is ↓ absorption of radioactive technetium (↓ 99mTc uptake) in the thyroid during transient hyperthyroidism
- de Quervain thyroiditis) (
- Diffuse toxic goiter/
- Nontoxic/multinodular goiter
- Maternal hypothyroidism ()
- Riedel thyroiditis ("Riedel struma")
Acute suppurative thyroiditis
- Definition: extremely rare bacterial infection of the thyroid glands
- Symptoms/clinical features: acute febrile course with tenderness
- Diagnosis: ultrasound
- Treatment: administration of broad-spectrum antibiotics (e.g., clindamycin or amoxicillin with clavulanate); in the case of abscess formation, opening of the abscess and culture of the abscess contents in addition to an antibiogram
- Complications: mediastinitis
The differential diagnoses listed here are not exhaustive.
- Levothyroxine (T4) replacement therapy
- Life-long monitoring
- Surgery is indicated in the presence of obstructive symptoms (e.g., dysphagia), malignancy, or may be considered for cosmetic reasons