Thyroid Free Thyroxine(FT4) for Fully Automated Immunoassay Analyzer IVD Re

EXPLANATION OF THE TEST

FT4 concentration in serum was highly correlated with effective thyroxine rate
(ETR). For hyperthyroidism, iatrogenic or toxic hyperthyroidism, FT4 will rise.
Various reasons make TBG rise, such as estrogen, hepatitis etc. which makesT4
rise, while FT4 did not rise; For various hypothyroidism, FT4 were
significantly lower than the normal range. Generally considered in clinical
diagnosis, the advantages of FT4 is not affected by the concentration of its
binding protein and of the impact of binding changes. It the best indicator of
thyroid function, especially combined with TSH.

Serum free thyroxine (FT4) is a sensitive indicator of thyroid function in
vitro tests. Even if the plasma thyroid-binding protein binding capacity and
concentration change under physiological and pathological conditions, it can
more accurately reflect the normal value of thyroid function free thyroxine
(FT4): 10～31pmol/L
Clinical significance of free thyroxine (FT4):
(1) Elevated: thyrotoxicosis, exophthalmos hyperthyroidism, painless
thyroiditis with hyperthyroidism, subacute thyroiditis with hyperthyroidism,
overdose of thyroid preparations, thyroid receptor refractory, chronic
thyroiditis with hyperthyroidism.
(2) Decreased: Hypothyroidism (primary) Pituitary or painless subacute
thyroiditis in the transient hypofunction stage Hypoalbuminemia.

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