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TRH Stimulation Test
| Item | Value |
|---|---|
| Approval req'd? | No |
| Available Stat? | No |
| Test code | |
| Test group | Thyroid tests |
| Performed by | China Basin Chemistry |
| In House Availability | Daily (day shift) |
| Method | Post-TRH measurement of TSH |
| Collection Instructions | Collect specimens at 0 and 15 or 30 minutes after giving 500 µg of TRH iv, and submit them for assay of TSH. Be sure to ote the time directly on each of the two samples |
| Container type | Gold top |
| Amount to Collect | 2 mL blood |
| Sample type | Serum |
| Preferred volume | 1 mL serum |
| Units | mIU/L |
| Normal range | TSH 2-4x basal and > 10 mIU/L 15-30 min post-TRH |
| Synonyms | TSH releasing Hormone |
| Turn around times | 1 day |
| Additional information | TRH (Thyroliberin) stimulation is useful only if results of the standard tests (TSH, Free T4) are equivocal. Responses are exaggerated in primary hypothyroidism, decreased in hyperthyroidism (natural or factitious) and in TSH deficiency. After IV administration of TRH, TSH normally rises 2- to 4-fold over baseline values. In subclinical hyperthyroidism and in hypothyroidism secondary to pituitary failure TSH levels do not rise normally; in primary hypothyroidism the response to TRH is exaggerated. TRH Stimulation was previously helpful when results of the T4 Index and TSH were equivocal, but with the advent of sensitive and accurate assays for TSH and Free T4, it has fallen into disuse. Also see Prolactin-TRH Stimulation. |
| Last Updated | 6/16/2008 3:03:15 PM |
| Entry Number | 923 |
If you have additional questions regarding this test, please call: 415-353-1667