3005977
print

T Uptake

T UPTAKE
Example Reports
Abnormal
Normal

Ordering Recommendation

Not recommended for routine thyroid disorder screening; for initial screening, refer to Thyroid Stimulating Hormone (0070145).
The preferred alternative to this test is Thyroxine, Free (Free T4) (0070138).

Methodology

Quantitative Electrochemiluminescent Immunoassay (ECLIA)

Performed

Sun-Sat

Reported

Within 24 hours

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation
Collect

Serum Separator Tube (SST). Also acceptable: Lavender (K2EDTA or K3EDTA), pink (K2EDTA), or green (lithium heparin).

Specimen Preparation

Allow specimen to clot completely at room temperature. Separate from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions

Grossly hemolyzed specimens.

Remarks
Stability

After separation of cells: Ambient: 8 days; Refrigerated: 2 weeks; Frozen: 2 years

Reference Interval

0.8-1.3 TBI

Interpretive Data

Thyroxine, Free (Free T4) (0070138) is the preferred test alternative for T Uptake and Free Thyroxine Index tests.

Compliance Category

FDA

Note

T uptake is of little clinical value alone; it is used to determine the free thyroxine index.

Hotline History

View Hotline History

 

Hotline History

Date of Change
Test Name Change
Methodology
Performance/Reported Schedule
Specimen Requirements
Reference Interval
Interpretive Data
Note
CPT Code
Component Change
Other Interface Change
New Test
Inactive
02/21/2023
X
N/A

CPT Codes

84479

Are you an ARUP Client? Click here for your pricing.

Components

Component Test Code* Component Chart Name LOINC
3005979 T Uptake 74795-6
* 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 Uptake
  • T4 uptake, S
  • T4U, serum
  • TBC
  • THBR
  • Thyroid binding ratio
  • Thyroxine-binding capacity
  • Thyroxine-binding index
  • Triiodothyronine uptake, serum
T Uptake