Is subacute thyroiditis related to colds? Can it heal on its own without treatment?

Author: Wei Junping, Chief Physician, Guang'anmen Hospital, China Academy of Chinese Medical Sciences

Reviewer: Mao Yonghui, Chief Physician, Beijing Hospital

Thyroiditis is divided into acute thyroiditis, subacute thyroiditis and chronic thyroiditis according to the severity of onset.

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Acute thyroiditis mainly refers to acute suppurative inflammation, including bacterial and fungal infections; chronic thyroiditis mainly refers to chronic inflammation of the thyroid gland caused by autoimmune abnormalities; subacute thyroiditis is related to viral infections, such as granulomatous thyroiditis and giant cell thyroiditis, which usually occurs one to two weeks after a cold and is more common in women aged 30-50.

Today we will mainly learn about subacute thyroiditis.

1. What are the symptoms of subacute thyroiditis?

Subacute thyroiditis is generally believed to be related to upper respiratory tract infection, and has different manifestations at different stages of the disease. In the early stage, the main manifestations are fever, thyroid pain or tenderness.

In addition, in the early stages of subacute thyroiditis, the inflammation will destroy the thyroid follicles, and the thyroid hormone stored in the thyroid follicles will be released into the blood. The increase in thyroid hormone will cause transient symptoms of hyperthyroidism, such as palpitations, hand tremors, sweating, weight loss, and increased frequency of bowel movements.

In the middle stage, the thyroid hormone stored in the thyroid follicles is exhausted and no longer released. Because the thyroid structure is damaged by inflammation, thyroid hormone cannot be synthesized, and symptoms of hypothyroidism will appear, manifested as fatigue, weakness, difficulty defecation, and fear of cold.

As the disease progresses to a certain period of time, thyroid function will slowly recover and enter the recovery period.

2. What tests are needed to diagnose subacute thyroiditis?

If there is a history of upper respiratory tract infection one to two weeks ago, fever and thyroid pain, subacute thyroiditis is suspected, and blood tests are usually required for erythrocyte sedimentation rate and blood routine. In the acute phase, white blood cells may be normal or elevated, and erythrocyte sedimentation rate generally increases.

It is necessary to test the thyroid function and determine whether the patient is in the hyperthyroidism or hypothyroidism stage through laboratory indicators. The immune function of the thyroid gland can be determined through thyroid peroxidase antibodies and thyroglobulin antibodies to differentiate it from other thyroiditis.

Imaging examinations include thyroid ultrasound, which shows an enlarged thyroid gland. Scattered or fused low-echoic patches with blurred boundaries can be seen in the thyroid gland. This is called "washout sign" and is a specific manifestation of subacute thyroiditis under ultrasound.

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In addition, you can do a thyroid iodine uptake test. After the thyroid gland is damaged, the iodine uptake rate will decrease. If conditions permit, you can also do a thyroid radionuclide scan.

3. How to treat subacute thyroiditis?

Theoretically, subacute thyroiditis is a self-healing disease, but if the fever persists for one to two months and the thyroid pain persists for one to two months, it will affect the quality of life, so people usually try to use some methods to relieve the symptoms and relieve the pain.

Subacute thyroiditis is mainly treated symptomatically. First, antipyretic treatment is performed. If the thyroid is very painful, non-steroidal anti-inflammatory drugs, such as aspirin and ibuprofen, can be used to relieve the pain. If the fever does not subside, the pain does not ease, and the symptoms recur repeatedly, affecting the quality of life, hormones can be used, and prednisone is generally used more often, to improve the inflammatory response. This is the conventional treatment method.

The thyroid function is damaged and transient symptoms of hyperthyroidism appear. The fast heart rate can be controlled with beta-blockers. Antithyroid drugs are generally not recommended. The use of antithyroid drugs should be done with caution because they may induce or aggravate hypothyroidism.

Of course, no matter what stage the disease is in, the acute stage, hyperthyroidism, hypothyroidism stage, or thyroid function recovery stage, Chinese medicine can be used for treatment, thereby reducing the use of glucocorticoids.

TCM has both internal and external treatments for subacute thyroiditis. Internal treatment emphasizes syndrome differentiation and treatment, whether it is exogenous wind-heat evil toxins, liver depression and qi stagnation, or qi deficiency. Prescriptions are made according to the etiology and pathogenesis, and according to the different stages of the disease. Combining the disease and the syndrome can quickly improve symptoms and restore thyroid function. External application of Chinese medicine to treat subacute thyroiditis is also very advantageous. Chinese medicine that clears heat, detoxifies, and relieves pain, plus borneol, is crushed and applied externally. After being absorbed through the skin, the Chinese medicine can directly act on the thyroid gland to achieve the purpose of pain relief. The pain relief effect is very clear.