What do you know about Thyroid-stimulating hormone? , (also known as TSH or thyrotropin )

What do you know about Thyroid-stimulating hormone? , (also known as TSH or thyrotropin ) :

 Thyroid-stimulating hormone is a hormone that stimulates the thyroid gland to produce thyroxine (T4), and then triiodothyronine (T3) which stimulates the metabolism of almost every tissue in the body.

 TSH stimulates the thyroid gland to secrete the hormones thyroxine (T4), which has only a slight effect on metabolism. T4 is converted to triiodothyronine (T3), which is the active hormone that stimulates metabolism. About 80% of this conversion is in the liver and other organs, and 20% in the thyroid itself .

 In adults, a standard reference range is between 0.4 and 3.0 µIU/mL (equivalent to mIU/L), but values vary slightly among labs. In the UK, guidelines issued by the Association for Clinical Biochemistry suggest a reference range of 0.4-4.5 mIU/L.

 The National Academy of Clinical Biochemistry (NACB) stated that it expected the normal range for adults to be reduced to 0.4–2.5 µIU/mL, because research had shown that adults with an initially measured TSH level of over 2.0 µIU/mL had "an increased odds ratio of developing hypothyroidism over the [following] 20 years, especially if thyroid antibodies were elevated"

 TSH concentrations in children are normally higher than in adults. In 2002, the NACB recommended age-related reference limits starting from about 1.3 to 19 µIU/mL for normal-term infants at birth, dropping to 0.6–10 µIU/mL at 10 weeks old, 0.4–7.0 µIU/mL at 14 months and gradually dropping during childhood and puberty to adult levels, 0.4–4.0 µIU/mL

 Diagnosis of disease :

 TSH concentrations are measured as part of a thyroid function test in patients suspected of having an excess (hyperthyroidism) or deficiency (hypothyroidism) of thyroid hormones. Interpretation of the results depends on both the TSH and T4 concentrations. In some situations measurement of T3 may also be useful.

 Monitoring

 The therapeutic target range TSH.. level for patients on treatment ranges between 0.3 to 3.0 μIU/mL .

 For hypothyroid patients on thyroxine, measurement of TSH alone is generally considered sufficient. An increase in TSH above the normal range indicates under-replacement or poor compliance with therapy.

 A significant reduction in TSH suggests over-treatment. In both cases, a change in dose may be required.

 For hyperthyroid patients, both TSH and T4 are usually monitored.

 Therapeutic :

 A synthetic drug called recombinant human TSH alpha (rhTSHα or simply rhTSH, (trade name Thyrogen), is manufactured by Genzyme Corp..

 The rhTSH is used to treat thyroid cancer.