Testosterone, Free, by Dialysis and Mass Spectrometry (Adult Males or Individuals on Testosterone Hormone Therapy)
Also known as: FREE T TMS
Use
This laboratory reference method is for the direct measurement of free testosterone. It is intended for use in adult males or individuals on testosterone hormone therapy, and it is not recommended for individuals with expected low concentrations of free testosterone, such as children and cisgender females. For individuals on testosterone hormone therapy, cisgender male reference intervals should be referred to. The test provides an accurate assessment of free testosterone levels for evaluating androgen status in the targeted population.
Special Instructions
It is important to collect the specimen between 6-10 a.m. to ensure accurate results due to diurnal variations in testosterone levels. The specimen should be separated from cells as soon as possible or within 2 hours of collection to prevent cell metabolism from affecting the results.
Limitations
This test should not be used when low testosterone concentrations are expected, such as those found in children and cisgender females. Additionally, reference intervals have not been established for males younger than 18 years or for cisgender females, which limits the applicability of the test for these groups. The test should not be the first choice when assessing free testosterone levels in populations with known low baseline testosterone.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 2991-8
Result Turnaround Time
2-6 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.4 mL
Container
Serum separator tube or green (sodium or lithium heparin)
Collection Instructions
Separate from cells ASAP or within 2 hours of collection.
Patient Preparation
Collect between 6-10 a.m.
Storage Instructions
Frozen
Causes for Rejection
EDTA plasma
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 24 hours |
| Refrigerated | 1 week |
| Frozen | 2 months |