|Test||TRH, SHORT , TSH STIMULATION WITH TRH (THYROID RELEASING HORMONE), SERUM|
|Methodology||Electrochemiluminescence Immunoassay (ECLIA)|
|Description||Useful for the diagnosis of hyperthyroidism and its cause, ie, primary (thyroid) , secondary (pituitary), or tertiary (hypothalamus) or to assess TSH production in suspected pituitary or hypothalamic disease. Test includes one TSH determination, post stimulation.
NOTE: This test, when ordered on Medicare patients, is subject to the National Coverage Determination (NCD) policy "Thyroid Testing". Please verify that the diagnosis code (ICD-9) you have chosen demonstrates medical necessity for the test as documented in the physician's patient record. The CMS web site or the NorDx Limited Coverage Documentation Guide are available to assist you with this verification. A properly executed Advance Beneficiary Notice (ABN) must be submitted with the specimen if medical necessity is not demonstrated by the ICD-9 code chosen.
|Specimen||Draw blood in either a plain, red-top tube or serum gel tube for TSH 30 minutes after TRH (Relefact®) injection. Spin down and send 1.0 mL (minimum volume: 0.5 mL) refrigerated serum.|
|Reference Values||Special report. Generally TSH levels peak 20 - 40 minutes after TRH injection with levels varying somewhat with age. Peak levels correlate with baseline TSH concentrations in hyperthyroidism. An absent response supports a pituitary defect. An augmented response suggests primary hypothyroidism.|
|Analytic Time||1 Day|
|Day(s) Test Set Up||Monday through Sunday|