Search results
The test, called a thyroid function test, looks at levels of thyroid-stimulating hormone (TSH) and thyroxine (T4) in the blood. Doctors may refer to this as "free" T4 (FT4). A high level of TSH and a low level of T4 in the blood could mean you have an underactive thyroid.
Thyroid function tests (TFT's) include thyroid stimulating hormone (TSH, also known as thyrotropin), free T4 (FT4; thyroxine) and free T3 (FT3; tri-iodothyronine). These tests are variably indicated for investigation of possible hypo- or hyper- thyroidism, for monitoring of adequacy of thyroid hormone replacement, for monitoring of anti-thyroid ...
A low level of TSH and high levels of T3 and/or T4 usually means you have an overactive thyroid. Doctors may refer to these measurements as "free" T3 and T4 (FT3 and FT4). What's considered normal varies depending on things such as your age and the exact testing technique used by the laboratory.
The blood test for TSH, which is the most sensitive marker of your thyroid status, is used as a biochemical marker to ensure that your thyroid hormone replacement is adequate. It is recommended that patients on thyroid hormone replacement should keep their TSH within the reference range.
TSH is recommended as the first line test. TSH and FT4 request only if thyroid disease is suspected or in monitoring of secondary hypothyroidism. Avoid requesting TFT request in acutely ill patient or inpatients. Check thyroid status 6- 8 weeks after recovery from an illness.
14 wrz 2023 · Thyroid function tests are blood tests which help to check the function of your thyroid gland. They are mainly used to detect an underactive thyroid gland (hypothyroidism) and an overactive thyroid gland (hyperthyroidism).
The diagnosis of hypothyroidism requires abnormal TFT results. A TSH greater than 10 mU/L combined with a FT4 below the reference range indicates the presence of overt primary hypothyroidism in ambulant subjects. The diagnosis of primary hypothyroidism requires the measurement of both TSH and FT4.
