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).

New York DOH Approval Status

This test is New York state 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

Methodology

Quantitative Electrochemiluminescent Immunoassay (ECLIA)

Performed

Sun-Sat

Reported

Within 24 hours

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

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 index
  • Triiodothyronine uptake, serum
  • Thyroxine-binding capacity
T Uptake