Reverse T3, Serum

Fasting Required: No

Specimen: Blood

Results: 7-10 Business Days

Description:
Since thyroid hormone acts like our internal thermostat, thyroid hormones may be suppressed in times of stress. One way this is done is by converting the thyroid hormone T4 into an inactive form of the active T3 hormone called reverse T3. This lowers the amount of available active T3 which can lead to hypothyroid type symptoms.

Methodology:
Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)

Reference Range(s):
8-25 ng/dL

Clinical Significance:
The assay may be useful in the diagnosis of nonthyroidal illness (NTI). Patients with NTI have low T3 concentrations and increased concentrations of rT3. RT3 may be useful in neonates to distinguish euthyroid sick syndrome from central hypothyroidism.

Alternative Name(s):
RT3,Triiodothyronine Reverse,rT3 ,Reverse Triiodothyronine,Reverse T3