Test Details
Methodology
Equilibrium dialysis, high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS-MS)
Result Turnaround Time
9 - 15 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
Dihydrotestosterone measurement is used to diagnose 5α-reductase deficiency and for the evaluation of androgen utilization. Dihydrotestosterone is produced by the reduction of testosterone by 5α-reductase in the target organs. Circulating dihydrotestosterone is tightly bound to sex hormone-binding globulin. The free fraction represents the dihydrotestosterone available to act on tissues.
Limitations
This test was developed, and the performance characteristics determined, by LabCorp. It has not been cleared or approved by the US Food and Drug Administration (FDA).
Specimen Requirements
Specimen
Serum (preferred) or plasma, frozen
Volume
3 mL
Minimum Volume
1.2 mL (Note: This volume does not allow for repeat testing.)
Container
Red-top tube, gel-barrier tube, or green-top (heparin) tube
Collection Instructions
Separate serum or plasma from cells within four hours of collection. Send serum or plasma in a plastic transport tube. Transfer specimen to a plastic transport tube before freezing. To avoid delays in turnaround time when requesting multiple test on frozen samples, please submit separate frozen specimens for each test requested.
Storage Instructions
Freeze. Stable at room temperature, refrigerated, or frozen for 14 days. Freeze/thaw cycles: stable x6
Causes for Rejection
EDTA plasma; grossly hemolyzed, icteric, or lipemic sample
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 504026 | DHT, Free, LCMS/Dialysis | 500143 | Dihydrotestosterone | ng/dL | 1848-1 | |
| 504026 | DHT, Free, LCMS/Dialysis | 504028 | DHT, Percent Free Dialysis | % | 13882-6 | |
| 504026 | DHT, Free, LCMS/Dialysis | 504029 | DHT, Free | pg/mL | 14047-5 | |
| Order Code | 504026 | |||||
| Order Code Name | DHT, Free, LCMS/Dialysis | |||||
| Order Loinc | ||||||
| Result Code | 500143 | |||||
| Result Code Name | Dihydrotestosterone | |||||
| UofM | ng/dL | |||||
| Result LOINC | 1848-1 | |||||
| Order Code | 504026 | |||||
| Order Code Name | DHT, Free, LCMS/Dialysis | |||||
| Order Loinc | ||||||
| Result Code | 504028 | |||||
| Result Code Name | DHT, Percent Free Dialysis | |||||
| UofM | % | |||||
| Result LOINC | 13882-6 | |||||
| Order Code | 504026 | |||||
| Order Code Name | DHT, Free, LCMS/Dialysis | |||||
| Order Loinc | ||||||
| Result Code | 504029 | |||||
| Result Code Name | DHT, Free | |||||
| UofM | pg/mL | |||||
| Result LOINC | 14047-5 |