Reverse T3 LC-MS/MS, Serum/Plasma

Clinical Utility

3,3′,5′-Triiodothyronine (reverse T3, rT3) is, along with 3,3,5′-Triiodothyronine (T3) a deiodinated metabolite of thyroxine (T4), the major secretory product of the thyroid gland and is secreted into the bloodstream. Unlike T3, however, rT3 is thought to be metabolically inert.
The process of 5′-monodeiodination that converts T4 to T3, and rT3 to diiodothyronine (DTT) is inhibited in a wide variety of conditions, collectively referred to as nonthyroidal illnesses (NTI) or the ‘euthyroid sick’ state. These conditions include fasting, malnutrition, poorly controlled diabetes mellitus, trauma, surgery, and systemic illness. Consequently, in patients with NTI the serum T3 level typically decreases, and the rT3 often, but not always, increases.

Method

Liquid chromatography-tandem mass spectrometry (LC-MS/MS)

Result Included

T3 Reverse

Aliases/Synonyms

T3 (Triiodothyronine) Reverse; T3 Reverse

Turnaround Time

9 days

Results

Referral Location

Out-of-Country

Last Updated

2024-03-15