Ordering Recommendation

Generally not recommended for routine evaluation of thyroid disorders, although may be considered in pregnant women.

Mnemonic
RT3 TMS
Methodology

Quantitative Liquid Chromatography-Tandem Mass Spectrometry

Performed

Sun-Sat

Reported

1-4 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Plain red or serum separator tube. Also acceptable: Lavender (EDTA) or pink (K2EDTA).

Specimen Preparation

Allow serum specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within two hours of collection. Transfer 2 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 1 mL)

Storage/Transport Temperature

Frozen.

Unacceptable Conditions

Grossly hemolyzed specimens

Remarks
Stability

Ambient: 24 hours; Refrigerated: 1 week; Frozen: 3 months

Reference Interval
Age
Reference Interval
0 -17 years Not established
18 years and older 9.0 - 27.0 ng/dl

Interpretive Data



Compliance Statement B: For laboratory developed tests not using a RUO kit, and for FDA approved, cleared or 510(k) exempt assays with alterations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.

Note
Hotline History
N/A
CPT Codes

84482

Components
Component Test Code* Component Chart Name LOINC
2007919 Triiodothyronine, Reverse - LC-MS/MS 3052-8
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • Reverse T3
  • Reverse T3, Serum
  • Reverse Triiodothyronine
  • RT3
  • T3
Triiodothyronine, Reverse by Tandem Mass Spectrometry