4 - 6 days
Test Updated:
Triiodothyronine, Reverse
Reverse T3 (Triiodothyronine)
T3 (Triiodothyronine), Reverse
RET3
RT3
Reverse T3, S
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Test Overview
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
In hospitalized or sick patients with low triiodothyronine (T3) values, elevated reverse triiodothyronine (rT3) values are consistent with "sick euthyroid" syndrome. Also, the finding on an elevated rT3 level in a critically ill patient helps exclude a diagnosis of hypothyroidism.
9 - 27.0 ng/dL
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.