Ordering Recommendation
Mnemonic
T3RT3RATIO
Methodology

Quantitative Liquid Chromatography/Tandem Mass Spectrometry

Performed

Mon-Sun

Reported

1-4 days

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

Serum separator tube or plain red. 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

After separation from cells: Ambient: 24 hours; Refrigerated: 1 week; Frozen: 3 months

Reference Interval
Available Separately
Component
Age
Reference Interval
Yes (2007918) Triiodothyronine, Reverse by Tandem Mass Spectrometry 0-17 years
18 years and older
Not Established
9.0-27.0 ng/dL
No Triiodothyronine, Total - LC-MS/MS Cord blood
0-3 days
4-30 days
1-23 months
2-6 years
7-11 years
12-19 years
20 years and older
14-86 ng/dL
96-292 ng/dL
62-243 ng/dL
81-281 ng/dL
83-252 ng/dL
92-219 ng/dL
83-215 ng/dL
80-200 ng/dL
No Triiodothyronine, Ratio (T3:RT3) 0-17 years
18 years and older
Not Established
4.2-11.0

Interpretive Data

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Compliance Category

Laboratory Developed Test (LDT)

Note
Hotline History
N/A
CPT Codes

84480; 84482

Components
Component Test Code* Component Chart Name LOINC
2007919 Triiodothyronine, Reverse - LC-MS/MS 3052-8
2008407 Triiodothyronine, Total - LC-MS/MS 3053-6
2008408 Triiodothyronine, Ratio (T3:RT3)
* 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
  • T3 total and reverse
  • Total and reversed Triiodothyronine T3 total and reverse
Triiodothyronine, Total and Triiodothyronine, Reverse with Ratio Calculation by Tandem Mass Spectrometry