How Is Graves' Disease Diagnosed?
In order to diagnose
Graves' disease, healthcare providers begin by asking a number of questions, including questions about possible
Graves' disease symptoms and signs. They will then perform a thorough physical examination. Finally, they may recommend several tests.
Tests Used to Diagnose Graves' Disease
A couple of tests are used to diagnose
hyperthyroidism and confirm Graves' disease as its cause. The first is a blood test that looks at thyroid-stimulating hormone (TSH) levels.
Thyroid-Stimulating Hormone Test
The TSH test is usually the first test a healthcare provider performs when considering a Graves' disease diagnosis. This test is the most accurate measure of thyroid activity available because TSH can be low even with small increases in thyroid function.
This test is based on the way TSH and thyroid hormone work together. The pituitary gland boosts TSH production when the thyroid is not making enough hormone; the thyroid normally responds by making more. Then, when the body has enough thyroid hormone circulating in the blood, TSH output drops. In people who produce too much thyroid hormone, the pituitary shuts down TSH production, leading to low or even undetectable levels in the blood.
Generally, a TSH reading below normal indicates hyperthyroidism, and a reading above normal means a person has
hypothyroidism.