TSH测试

定义

A TSH测试 measures the amount of thyroid stimulating hormone (TSH) in your blood. TSH is produced by the pituitary gland. It prompts the 甲状腺 to make and release thyroid hormones into the blood.

选择的名字

Thyrotropin; 甲状腺 stimulating hormone; Hypothyroidism - TSH; Hyperthyroidism - TSH; Goiter - TSH

如何执行测试

A 血液样本 是必要的. Other thyroid tests that may be done at the same time include:

• T3测试 (免费或全额)
• T4测试 (免费或全额)
• Anti-TPO (antibodies against thyroid peroxidase)

如何准备考试

There is no preparation needed for this test. Ask your health care provider about any medicines you are taking that may affect the test results. DO NOT stop taking any medicines without first asking your provider.

Medicines you may need to stop for a short time include:

• 胺碘酮
• 多巴胺
• 锂
• 碘化钾
• Prednisone or other glucocorticoid medicines

The vitamin biotin (B7) can affect the results of the TSH测试. If you take biotin, talk to your provider before you have any thyroid function tests.

考试的感觉如何

When the needle is inserted to draw blood, some people feel moderate pain. 其他人只感到刺痛或刺痛. Afterward, there may be some throbbing or a slight bruise. 这很快就会消失.

为什么要进行测试

Your provider will order this test if you have symptoms or signs of an 过分活跃的 or 不够 甲状腺. It is also used to monitor treatment of these conditions.

Your provider may also check your TSH level if you are planning to get pregnant.

正常的结果

正常取值范围为0.5 to 5 microunits per milliliter (µU/mL).

TSH值在白天会有所变化. It is best to have the test early in the morning. Experts do not fully agree on what the upper number should be when diagnosing thyroid disorders. Some labs will use a higher normal range limit for older people (even as high as 7 µU/mL).

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.

If you are being treated for a thyroid disorder, your TSH level will likely be kept between 0.5和4.0µU/mL，以下情况除外:

• A pituitary disorder is the cause of the thyroid problem. 低TSH是可以预料的.
• You have a history of certain types of thyroid cancer. A TSH value below the normal range may be best to prevent the thyroid cancer from coming back.
• 一个女人怀孕了. The normal range for TSH is different for women who are pregnant. Your provider may suggest that you take thyroid hormone, even if your TSH is in the normal range.

异常结果意味着什么

A higher-than-normal TSH level is most often due to an 不够 甲状腺 (hypothyroidism). 造成这个问题的原因有很多.

A lower-than-normal level may be due to an 过分活跃的 甲状腺, which can be caused by:

• 格雷夫斯病
• 中毒性结节性甲状腺肿 或者多结节性甲状腺肿
• Too much iodine in the body (due to receiving iodine contrast used during imaging tests, 如CT扫描)
• Taking too much thyroid hormone medicine or prescribed natural or over-the-counter supplements that contain thyroid hormone

Use of certain medicines may also cause a lower-than-normal TSH level. 这些包括糖皮质激素/类固醇, 多巴胺, 某些化疗药物, and opioid painkillers such as morphine.

风险

There is little risk involved with having your blood taken.Veins and arteries vary in size from one person to another and from one side of the body to the other. Obtaining a 血液样本 from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

• 大出血
• 昏厥或感到头晕
• 多次穿刺定位静脉
• Hematoma (blood buildup under the skin)
• Infection (a slight risk any time the skin is broken)

参考文献。

Guber HA, Oprea M, Rusell YX. 内分泌功能评价. 见:McPherson RA, Pincus MR，编辑. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24日艾德. Philadelphia, PA: Elsevier; 2022:chap 25.

Jonklaas J, Cooper DS. 甲状腺. 参见:Goldman L, Schafer AI主编. Goldman-Cecil医学. 26日艾德. Philadelphia, PA: Elsevier; 2020:chap 213.

Salvatore D, Cohen R, Kopp PA, Larsen PR. 甲状腺 pathophysiology and diagnostic evaluation. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. 威廉斯内分泌学教科书. 14日艾德. Philadelphia, PA: Elsevier; 2020:chap 11.

Weiss RE, Refetoff S. 甲状腺功能检查. In: Jameson JL, De Groot LJ, de Kretser DM, et al, eds. 内分泌学:成人和儿童. 7日艾德. Philadelphia, PA: Elsevier Saunders; 2016:chap 78.