Treatment 1. Follow-up: If the thyroid function is normal, follow-up is the main measure for HT management. It is generally recommended to follow up every six months to one year, mainly to check thyroid function and, if necessary, to perform ultrasound examination of the thyroid gland. 2. Etiological treatment: There is no treatment method for the cause of HT. Low iodine diet is advocated. In recent years, there are various new methods to treat this disease from the perspective of immune regulation, which can make the patient’s thyroid autoantibody level decrease and the enlarged thyroid gland shrink. Selenium is an essential trace element in the body and is an antioxidant. It has important physiological functions such as anti-aging, anti-tumor, cardiovascular protection, and antagonism to heavy metal toxicity. Selenium can improve the immune function of the body. Selenium intervention therapy can reduce or inhibit the immune damage of autoimmune thyroiditis. 3, treatment of hypothyroidism and subclinical hypothyroidism: patients with existing hypothyroidism or obvious subclinical hypothyroidism must be treated with thyroid hormone replacement therapy. The goal of treatment is to restore serum TSH and thyroid hormone levels to the normal range. The dose of levothyroxine sodium (L-T4) therapy depends on the patient’s condition, age, weight and individual differences. The average dose for adult treatment is 125 μg/day, 1.6-1.8 μg/(kg/day) by body weight. Elderly patients require a lower dose of approximately 1.0 μg/(kg/day). Start with a low dose, especially in elderly patients with cardiovascular disease, a long course of disease, and severe disease. Generally start with 25-50 μg/day and increase by 25 μg every 1 to 2 weeks until the goal of complete replacement is reached. Those with heart disease are advised to start with 12.5 to 25 μg per day and increase by 12.5 to 25 μg every 2 weeks to avoid inducing and aggravating heart disease conditions. The ideal way to take L I T4 is to take one dose in the morning on an empty stomach. The interval between doses and other drugs should be at least 4h, because some drugs and foods can affect its absorption and metabolism. At the beginning of treatment, the relevant hormone indexes are measured every 4 to 6 weeks. The dose is then adjusted according to the test results until the treatment goal is reached. After reaching the treatment target, the relevant hormone indexes need to be rechecked every 6 to 12 months. 4. Treatment of goiter: For those without hypothyroidism, levothyroxine sodium (L-T4) may have the effect of reducing goiter, especially in patients with recent goiter. In patients with long-standing goiter, thyroid hormone therapy is usually not effective. Glucocorticoids can reduce the size of an enlarged thyroid gland and lower the titer of antithyroid antibodies in the blood; treatment with corticosteroids can reduce local symptoms in patients with a rapidly growing and painful thyroid gland. However, corticosteroids are not recommended due to side effects and the possibility of recurrence after discontinuation of the drug. In patients with significant, painful, tracheal compression, and ineffective medical treatment, surgical removal of the thyroid gland may be considered. Postoperative hypothyroidism often occurs and requires long-term thyroid hormone replacement therapy. 5. The treatment of Hashimoto’s thyroiditis with suboptimal hypothyroidism is the most controversial. For TSH >10 mIU/L, levothyroxine therapy is generally advocated. In view of the fact that overtreatment may bring a series of adverse effects, such as cardiovascular disease and osteoporosis, most scholars suggest that follow-up of patients with TSH between 4.5 and 10 mIU/L is sufficient, especially in elderly patients. Of course, for patients with obvious symptoms, TPOAb-positive patients, those who want to get pregnant, pregnant women, and children and adolescents, levothyroxine should be used routinely to treat suboptimal hypothyroidism. Treatment of TPOAb-positive pregnant women: for women with known positive TPOAb before pregnancy, thyroid function must be checked to confirm normal thyroid function before pregnancy; for women with positive TPOAb before pregnancy with clinical hypothyroidism or subclinical hypothyroidism, thyroid function must be corrected to normal before pregnancy; for pregnant women with positive TPOAb and normal thyroid function, thyroid function should be reviewed regularly during pregnancy. In case of hypothyroidism or low T4emia, L-T4 treatment should be given immediately, otherwise it will lead to insufficient supply of thyroid hormones to the fetus and affect its neurodevelopment. 7. Hashimoto’s disease combined with nodules requires attention to determine the nature of the nodules: if the nodules are still small, regular ultrasound review is recommended, the first time at 3 months. If the patient has concerns, needle aspiration biopsy with cytology can be performed, and if the diagnosis is not clear, surgical excision can be performed. The incidence of Hashimoto’s thyroiditis combined with thyroid cancer has been on the rise in recent years. Hashimoto’s thyroiditis may be a high-risk factor for the development of thyroid cancer. The long-term prognosis for most autoimmune thyroiditis is good and is a benign process. The natural progression of the disease to hypothyroidism is slow. Hypothyroidism due to autoimmune thyroiditis was previously thought to be permanent. Recent data show that some patients with hypothyroidism caused by autoimmune thyroiditis can be temporarily hypothyroid. About 20% of these patients have spontaneous recovery of thyroid function when replaced with thyroid hormone. In addition, it has been observed that many enlarged thyroid glands can shrink or disappear, that previously detected thyroid nodules disappear or shrink during follow-up, and that hard and tough thyroid glands may become soft.