Chronic lymphocytic thyroiditis, also known as autoimmune thyroiditis, is a chronic inflammatory autoimmune disease that uses its own thyroid tissue as the antigen and is the leading cause of primary hypothyroidism. It was first reported as Hashimoto’s thyroiditis by Hashimoto at Kyushu University in Japan (1912) in the German Medical Journal. The incidence has increased rapidly in recent years. The cause of the disease is still unknown and is related to environmental and genetic factors. Clinical manifestations: The course of the disease is slow and may be characterized by a transient hyperthyroid phase – a normal thyroid function phase – a hypothyroid phase. (1) Early stage may be asymptomatic, and when goiter appears, the course of the disease has reached 2-4 years on average. (2) Common symptoms are generalized weakness, and a few patients have local pressure or vague pain in the thyroid area. (3) The thyroid gland is mostly bilaterally symmetrical and diffusely enlarged. (4) A few cases may be accompanied by enlarged lymph nodes in the neck, but they are soft. If the disease is prolonged, hypothyroidism may appear after several years, manifesting as thyroid atrophy, mucinous edema, slow heart rate, generalized aches and pains, weakness, and thick skin. Tests (1) Anti-thyroid antibody assay Anti-thyroglobulin antibody (TGAb) and thyroid peroxidase antibody (TPOAb) assay are helpful for diagnosis. (2) Thyroid function measurement serum T3, T4, FT3, FT4 are generally normal or low, TSH level can reflect the patient’s metabolic status, generally TSH is normal in normal thyroid function, but elevated in hypothyroidism. (3) Thyroid ultrasound shows diffuse significant or nodular hyperplasia of the thyroid gland. (4) Cytology Fine needle aspiration cytology (FNAC) and histological examination of frozen sections of tissue are decisive for confirming the diagnosis. Treatment and prognosis
The aim of treatment of chronic lymphocytic thyroiditis is mainly to correct abnormal thyroid function. Patients with combined hypothyroidism require long-term levothyroxine sodium replacement therapy; appropriate iodine intake. If TPOAb is known to be positive before pregnancy, thyroid function must be checked to confirm normal thyroid function before pregnancy; thyroid function should be reviewed regularly during pregnancy. Most patients have a good prognosis and the progression to hypothyroidism is slow.