Thyroid Diseases
What tests are used to detect a problem with the thyroid?
The first test your doctor will usually request to detect a problem with your thyroid gland is a TSH test. If your TSH level is abnormal, the doctor will usually request a free T4 test to confirm the diagnosis. A free T3 test may be requested as well.
- TSH – to test for hypothyroidism, and hyperthyroidism, to screen newborns for hypothyroidism, and to monitor treatment with thyroid hormone tablets.
- Free T4 – to test for hypothyroidism and hyperthyroidism.
- Free T3 – to test for hyperthyroidism.
Additional tests that may be performed include:
When are these lab tests requested?
Since one out of every 4,000 infants is born without a working thyroid gland, there is a UK screening programme for all newborn babies looking for hypothyroidism. This occurs approximately 1 week after birth and uses a drop of blood taken from a heel prick which is sent to the laboratory for a TSH test.
Thyroid function tests are also requested when a doctor notices that a patient has symptoms which can occur in thyroid disease. In hypothyroidism for instance a patient might show signs of fatigue, weight gain, increased sensitivity to cold, or skin dryness. In hyperthyroidism the signs might include fatigue, weight loss, increased sensitivity to heat, and nervousness. Tests are also requested in individuals who have a family history of thyroid disorders.
Non-Laboratory Tests
