The incidence of Hashimoto’s thyroiditis varies from 5-10% in the population, with an incidence of 1-2% in Japanese women, with an increasing trend in recent years. I. Symptoms Hashimoto’s thyroiditis can manifest as an enlarged thyroid gland or as an atrophied thyroid gland. Some people believe that the latter is the end stage of the former, but others believe that the latter is idiopathic hypothyroidism, and Hashimoto’s thyroiditis are two separate diseases. The thyroid gland is seen to be diffusely and symmetrically enlarged, with an intact, thickened, smooth envelope and a grayish-white, tough, rubbery texture. Histologically, the thyroid follicles are small, with reduced gliosis, varying degrees of lymphocyte and plasma cell infiltration and fibrosis, forming lymphoid follicles and germinal centers, and some epithelial cells are enlarged, forming eosinophils. Classification The pathological types can be divided into lymphocytic type, eosinophilic type and fibrotic type. The lymphocytic type is a moderate lymphocytic infiltrate with significant glial phagocytosis and no eosinophils; the eosinophilic type is a dense lymphocytic infiltrate with lymphoid follicle formation, significant eosinophils, and mild fibrosis; the fibrous type is a plasma cell infiltrate with eosinophils and significant fibrosis. Focal chronic lymphocytic thyroiditis is not uncommon and is characterized by patches of normal thyroid follicles or normal thyroid lobular structures around or in the lesion. Diagnosis 1. Normal or low thyroid function is associated with different periods of Hashimoto’s disease development. Most thyroid function is normal, but it may be reduced in those with a long course of disease. Sometimes the thyroid function is hyperactive and the duration is variable. 2. The thyroglobulin and thyroid microsomal antibodies are significantly elevated and can last for a long time, up to 80% for several years or even more than 10 years. The two antibodies have special significance for the diagnosis of this disease. 3. The iodine uptake rate of the thyroid gland may be normal, elevated or decreased. Nuclear scan is unevenly distributed, with irregular sparse and concentrated areas with unclear borders or cold nodules. 4. Thyroid ultrasound shows diffuse enlargement with thickened light spots and diffuse echogenic hypoechogenicity with uneven distribution. 5. Thyroid puncture biopsy has lymphocytes, lymphoid follicle formation, may have eosinophils, and fibrosis. Treatment There is no reliable treatment to eliminate the disease, but symptomatic treatment is available for thyroid size and thyroid function abnormalities. If the thyroid function is normal, the thyroid gland is small and there are no obvious symptoms of compression can be followed and observed. If the enlarged thyroid gland compresses the neighboring organs or affects the appearance, some people propose to take thyroid hormone to shrink the thyroid gland and most cases end up with hypothyroidism, and early medication is better than the final. Those who develop hypothyroidism in Hashimoto’s disease are replaced with thyroid hormone, L-T4 is better than thyroid tablets, starting with small amounts and gradually increasing until the gland shrinks and sensitive TSH is reduced to normal. When hyperthyroidism occurs in Hashimoto’s disease if it is transient, B-blockers can be used. Even if antithyroid drugs are used, small doses and short applications should be chosen; if it is Hashimoto’s hyperthyroidism should be treated as toxic diffuse goiter without surgery and iodine 131 radiotherapy, unless surgery is performed after suppressive treatment for enlarged thyroid gland compression or suspected malignancy. Glucocorticosteroids can make the enlarged thyroid gland smaller and reduce the antibody titer, which can recur after stopping the drug and has potential adverse effects, so they are not recommended.