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Preferred Sample Type

Dihydrotestosterone

Suitable Specimen Types

  • Serum
  • Li Hep Plasma
1.5 ml whole blood minimum

Specimen Transport

First class post

Sample Processing in Laboratory

Usual

Sample Preparation

Spin specimen and separate serum/plasma, ideally at least 0.5ml serum/plasma needed for analysis

Turnaround Time

1 batch per month

Sample Stability

Store separated serum at 4 ºC

Dihydrotestosterone

General Information

Patients presenting with 46XY karyotype and female genitalia may lack the enzyme testosterone 5 alpha-reductase. This enzyme activity is required for full masculinisation of the external genitalia during intrauterine life. At puberty, virulization of affected subjects (often brought up as girls) may occur. 5-alpha-reductase deficiency can be diagnosed after puberty by measurement of testosterone and 5-alpha-dihydrotestosterone concentrations in the same serum sample. Before puberty, stimulation of androgen production with hCG is usually required to acheive concentrations that can be measured with the precision necessary for accurate diagnosis.

Patient Preparation

This may be required if test is combined with an hCG stimulation test. Protocol from relevant Ref Lab is required to enable interpretation of results.

Notes

None

Reference Range

Provided by reference laboratory

Specifications

  • EQA Scheme?: No
  • EQA Status: No EQA scheme available