Diagnostic criteria for Hashimoto's thyroiditis

Hashimoto's thyroiditis is a chronic lymphatic disease that is common in middle-aged women. It is also an autoimmune disease. We can observe that the patient's thyroid gland will become enlarged, and the patient will also experience thyroid pain in daily life. The development of Hashimoto's thyroiditis is very slow, and it is not very dangerous when it occurs, so it is often ignored by patients. It can only be discovered early if a person has the habit of having physical examinations.

Hashimoto's thyroiditis, also known as chronic lymphocytic thyroiditis, is an autoimmune disease. Chronic lymphocytic thyroiditis is more common in middle-aged people, but it can affect any age group. The incidence rate in women is significantly higher than that in men, about 20:1. The onset is insidious and slow. The thyroid enlargement is often discovered accidentally and is of medium size. A few patients may have local discomfort or even pain, which can be easily confused with subacute thyroiditis. Most goiters are symmetrical, with enlargement of the pyramidal lobes. The surface of the gland may be lobed and tough like rubber. The thyroid function is mostly normal, but some patients may have hyperthyroidism, which is seen in young patients and is called Hashimoto's hyperthyroidism. Hypothyroidism may occur in the later stage, and a few may present with myxedema.

1. Thyroid function tests vary depending on the course of the disease.

(1) In the early stage, serum T4 and T3 are normal, but TSH is elevated; in the later stage, serum T4 decreases, T3 is normal or decreases, and TSH increases.

(2) The thyroid iodine uptake rate is normal or increased in the early stage, but can be inhibited by T3; in the later stage, the iodine uptake rate decreases and TSH injection does not increase the rate.

2. Immunological examination shows a significant increase in the titers of anti-thyroglobulin antibodies (TGA) and anti-thyroid microsomal (peroxidase) antibodies (TMA) in the blood. When both are greater than 50% (radioimmunoassay double antibody method), it has diagnostic significance and can last for several years or more than ten years.

3. Other examinations showed that the erythrocyte sedimentation rate was increased, which could reach 100 mm/h, serum albumin was decreased, and r-globulin was increased.

2. Further inspection

1. SPECT thyroid scans may be evenly or unevenly distributed and may appear as “cold nodules”.

2. For patients with atypical clinical manifestations and low or negative antibody titers, fine needle aspiration cytology or tissue biopsy can be performed for pathological diagnosis.

3. Key points of diagnosis

1. In middle-aged women, diffuse enlargement of the thyroid gland with a firm texture should be considered regardless of thyroid function.

2. A significant increase in serum TGA and TMA titers (>50%) can basically confirm the diagnosis.

3. For patients with atypical clinical manifestations, the antibody titer must be >= 60% for two consecutive times. For patients with hyperthyroidism symptoms, the antibody titer must be >= 60 for more than half a year.

4. This disease needs to be differentiated from thyroid cancer, the latter of which is antibody-negative. Literature reports that the incidence of thyroid cancer in this disease is 5%-17%.