Testosterone, Free

CPT Code: 84402
Order Code: 1385
ABN Requirement: No
Specimen: Serum
Volume:  2.8 mL
Minimum Volume:  1.3 mL
Container: Red Top (no gel barrier) tube

Collection:

  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 5 times immediately after draw. Do not shake.
  3. Let tube stand in a vertical position to allow blood to clot 30 minutes.
  4. Centrifuge for 10 minutes.
  5. Aliquot serum into a labeled transport tube and cap tightly.

Patient Information: Administration of STRENSIQ may interfere in certain assays and may falsely elevate values. For patients receiving STRENSIQ, consideration should be given to alternate methods.

*Special Information: Please specify age and sex on the test requisition form.*

Transport: Store serum at 2°C to 8°C after collection and ship the same day per packaging instructions included with the provided shipping box.

Stability:

Ambient (15-25°C): 7 days
Refrigerated (2-8°C):
7 days
Frozen (-20°C):
2 years

Causes for Rejection: Specimens other than red top (no gel barrier) serum; improper labeling; samples not stored properly; samples older than stability limits; gross hemolysis; gross lipemia

Methodology: Immunochemiluminometric Assay (ICMA), Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS), Spectrophotometric, Calculation (CALC)

Turn Around Time: 3 to 4 days

Reference Range:

Age Male (pg/mL) Female (pg/mL)
<1 year Not Established Not Established
1-11 years ≤1.3 ≤1.5
12-13 years ≤64 ≤1.5
14-17 years 4.0-100.0 ≤3.6
18-69 years 46.0-224.0 0.2-5.0
70-89 years 6.0-73.0 0.3-5.0
>89 years Not Established Not Established

Pediatric data from Clin Endocrinol (1989) 31:201-207 and Acta Endocrinologica (1985) 109:276-280.

The concentration of free testosterone is derived from a mathematical model using total testosterone by LCMSMS, sex hormone binding globulin, and albumin.

Clinical Significance: Test is helpful in assessing testicular function in males, and in managing hirsutism and virilization in females.

The CPT codes provided 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 payer being billed.