Ordering Recommendation

Laboratory reference method for the direct measurement of free testosterone. Not recommended when low concentrations of free testosterone, such as those found in children and cisgender females, are expected. For these individuals, the preferred test is Testosterone, Free (Adult Females, Children, or Individuals on Testosterone-Suppressing Hormone Therapy) (0081059). Calculated free testosterone is generally adequate for most evaluations of hypogonadism; refer to Testosterone, Free (Adult Males or Individuals on Testosterone Hormone Therapy) (0070111).

Mnemonic

FREE T TMS

Methodology

Quantitative Equilibrium Dialysis/High Performance Liquid Chromatography-Tandem Mass Spectrometry

Performed

Sun, Wed-Sat

Reported

1-6 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation

Collect between 6-10 a.m.

Collect

Serum separator tube or green (sodium or lithium heparin).

Specimen Preparation

Separate from cells ASAP or within 2 hours of collection. Transport 1 mL serum or plasma. (Min: 0.4 mL)

Storage/Transport Temperature

Frozen.

Unacceptable Conditions

EDTA plasma.

Remarks
Stability

After separation from cells: Ambient: 24 hours; Refrigerated: 1 week; Frozen: 2 months

Reference Interval

Male Free Testosterone, pg/mL
18 years and older: 47-244 pg/mL

Interpretive Data

This laboratory reference method for the direct measurement of free testosterone is not recommended when low testosterone concentrations, such as those found in children and cisgender females, are expected. For these individuals, the preferred test is Testosterone, Free (Adult Females, Children, or Individuals on Testosterone-Suppressing Hormone Therapy) (ARUP test code 0081059).

For individuals on testosterone hormone therapy, refer to cisgender male reference intervals. No reference intervals have been established for males younger than 18 years or for cisgender females. For a complete set of all established reference intervals, refer to ltd.aruplab.com/Tests/Pub/2003246.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Compliance Category

Laboratory Developed Test (LDT)

Note

Hotline History

N/A

CPT Codes

84402

Components

Component Test Code* Component Chart Name LOINC
2003247 Testosterone, Free by Dialysis 2991-8
* 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

  • Direct Dialysis (Testosterone, Free, Adult Males by ED/LC-MS/MS)
Testosterone, Free, by Dialysis and Mass Spectrometry (Adult Males or Individuals on Testosterone Hormone Therapy)