Testosterone, Free

Overview

  • EPIC Code:
  • LAB2565
  • Soft Test Code:
  • TSFR
  • Send Out Test Code:
  • 18944
Alternate Names
  • Testosterone, Free Direct
Clinical Significance

Test is helpful in assessing testicular function in males and managing hirsutism and virilization in females.


Specimen Collection & Preparation

Specimen Requirements

2.8 mL Serum from a Red Top Tube in a Plastic Vial


Transport And Storage

7 days Ambient (transport)
7 days Refrigerated
2 years Frozen


Collection Instructions

Please specify age and sex on test request form.


Minimum Volume

1.3 mL Serum


Neonatal Volume

Clinical Interpretation

Reference Range:

Adult Males (pg/mL) Females (pg/mL)
18-69 Years 46.0-224.0 0.2-5.0
70-89 Years 6.0-73.0 0.3-5.0
     
Pediatric Males (pg/mL) Females (pg/mL)
<1 Year Not available Not available
1-10.9 Years ≤1.3 ≤1.5
11-11.9 Years ≤1.3 ≤1.5
12-13.9 Years ≤64 ≤1.5
14-17.9 Years 4.0-100.0 ≤3.6
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 LC/MS/MS, sex hormone binding globulin, and albumin.


Methodology:
  • Immunochemiluminometric Assay (ICMA)
  • Liquid Chromatography/Tandem Mass Spectrometry
  • Spectrophotometric
Clinical Significance

Test is helpful in assessing testicular function in males and managing hirsutism and virilization in females.


Production Schedule

Sites Performed
  • Quest - Chantilly
Days Performed
Monday
Tuesday
Wednesday
Thursday
Friday
Departments
  • Sendouts - Clinical
Turn Around Time

2 to 4 days


Coding & Compliance

CDM

00916389


CPT Coding

84402