Summary
The thyroid gland is the largest endocrine gland in the body that secretes two important iodinated hormones, T3 and T4. In addition, there is TSH (thyroid hormone stimulating hormone), which increases its secretion following a decrease in blood levels of thyroid hormones. Thyroid hormones are important for the activity of almost all tissues in the body. This gland regulates the body’s energy metabolism and affects brain growth, skeletal growth, embryonic development, nervous development and reproductive function, respiration, heart, body temperature, muscle strength, dry skin, menstrual cycle, weight and surface area. Cholesterol is influential. Thyroid disease is one of the most common hormonal disorders and today it is common for thyroid tests to be performed in clinical laboratories.
What are thyroid function tests?
TSH, FT4, and FT3 are commonly tested for a variety of blood tests for thyroid function. To do this, the patient takes a blood sample and is sent to the department of hormones, immunology and serology for testing. In addition to reporting the measured thyroid hormone levels to the clinician, laboratories use reference intervals to compare the patient’s blood test result with that of healthy individuals.
TSH test
The most sensitive screening test is to detect possible thyroid abnormalities. In general, TSH increases in hypothyroidism or hypothyroidism, and TSH decreases in hyperthyroidism or hyperthyroidism. An abnormal result of this test requires one or more more tests to find the cause of the problem.
T4 test
It exists in two forms free (FT4) and bound to protein (T4). Decreased levels of both forms (FT4 and T4) are seen in hypothyroidism. However, in certain cases, if corticosteroids are used to treat shortness of breath, arthritis, skin conditions, etc., the level of binding protein (T4) decreases and as a result, in these people, the level of serum (T4) may be low. And not known as hypothyroidism. Increased levels of any free (FT4) and protein-bound (T4) form are seen in hyperthyroidism. In particular, pregnant women and women taking birth control pills have high levels of binding proteins in their blood and therefore may not be known as hyperthyroidism despite their high serum T4 levels.
T3 test
If your clinician suspects hyperthyroidism in someone with a normal FT4 level, a T3 test can be helpful to confirm this condition. This test is not suitable for diagnosing hypothyroidism; Because its level does not decrease until hypothyroidism becomes acute.
Uptake T3 test
It is a specialized complementary test for indirect measurement of thyroxine-binding protein in plasma. Decreases in this test are seen in pregnancy, high levels of estrogen and acute hepatitis. Increases in this test include the use of anabolic hormones and glucocorticoids, nephrotic syndrome, and genetic deficiency of TBG.
TSI test (thyroid stimulating immunoglobulin)
This test is used to measure autoantibodies in the diagnosis of autoimmune disease.
Anti TPO (thyroid peroxidase antibody) test
This test is also used to measure autoantibodies in the diagnosis of autoimmune disease. TPO is an enzyme present in the thyroid gland that plays a key role in the production of thyroid hormones. In the Anti TPO test, we look for autoimmune antibodies against TPO in the blood, which if present in the blood, is often the cause of autoimmune disease. This test is usually done with an anti-thyroglobulin antibody test, which greatly increases specificity and sensitivity.
What are the requirements for thyroid tests?
The best conditions for thyroid tests are early in the morning (before 10 am) and on an empty stomach. Also, if the client is taking a certain drug, be sure to inform the laboratory.
