Thyroid Panel

Test Code

CPT Codes
84436, 84479

T3 Uptake,
T4 (Thyroxine) Total
Free T4 Index (T7)

Preferred Specimen
1 mL serum collected in a serum separator tube (SST®)

Minimum Volume
0.5 mL

Other Acceptable Specimens
Plasma collected in a sodium or lithium heparin (green-top) tube

Transport Temperature
Room temperature

Specimen Stability
Room temperature: 7 days
Refrigerated: 7 days
Frozen: 28 days

Immunoassay (IA)

Setup Schedule
Set up: Daily; Report available: Next day

Reference Range
T3 Uptake 22-35 %

T4 (Thyroxine), Total
<1 Month 4.5-17.2 4.5-17.2
1-23 Months 5.9-13.9 5.9-13.9
2-12 Years 5.7-11.6 5.7-11.6
13-20 Years 5.1-10.3 5.3-11.7
>20 Years 4.9-10.5 5.1-11.9

Free T4 Index (T7) 1.4-3.8

Clinical Significance
For diagnosis of hypothyroidism and hyperthyroidism.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.