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



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