Testosterone, Total Males (Adult), Immunoassay

Test Code

CPT Codes

Note: When requesting Total Testosterone for pediatric and female patients please refer to Testosterone, Total, LC/MS/MS, test code: 15983.

Preferred Specimen
1 mL serum

Patient Preparation
Due to changes in testosterone levels throughout the day, two morning (8-10 AM) specimens obtained on different days are recommended by The Endocrine Society for screening.

Minimum Volume
0.5 mL

Specify age and sex on test request form.
Dietary supplements containing biotin may interfere in assays and may skew results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.

Note: This assay should be performed on adult (> or = 18 years) males.

Transport Container
Plastic screw-cap vial

Transport Temperature
Room temperature

Specimen Stability
Room temperature: 5 days
Refrigerated: 7 days
Frozen: 21 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross icteric

Immunoassay (IA)

Setup Schedule
Set up: Mon-Sat; Report available: Next day

Immunoassay does not provide sufficient sensitivity in detecting low concentrations among non-adults and women.

Reference Range
Adult Male 250-827 ng/dL

All test requests for Testosterone on female and pediatric (<18 years) patients must use test code 15983 - Testosterone, Total, LC/MS/MS.

Clinical Significance
Testosterone circulates almost entirely bound to transport proteins: Normally less than 1-2% is free. The principal transport protein for testosterone is known as sex hormone binding globulin (SHBG) or testosterone-estradiol binding globulin (TeBG). Testosterone measurements are used to assess erectile dysfunction, infertility, gynecomastia, and osteoporosis and to assess hormone replacement therapy.

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.