Testosterone

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Testosterone
TT, FRTT, free testosterone
Serum (brown), Plasma (orange)
24hrs

The determination of testosterone in women is helpful in the diagnosis of androgenic syndrome (AGS), polycystic ovaries (Stein-Leventhal syndrome) and when an ovarian tumour, adrenal tumour, hirtuism, adrenal hyperplasia or ovarian insufficiency is suspected. Testosterone is determined in men when reduced testosterone production is suspected, e.g. in hypogonadism, oestrogen therapy, chromosome aberrations (as in the Klinefelters syndrome) and liver cirrhosis. In both sexes testosterone may be used as part of an indirect assessment of pituitary function (assessing activity of LH).

A calculated free testosterone is available upon request, principally for use in the diagnosis of male androgen deficiency. If free testosterone is required, please contact the laboratory via secure email (peh-tr.chemmimm@nhs.net) with information regarding the patient on which free testosterone is required (name, DOB, patient number) and the clinical indications for the request. Free testosterone is calculated from the total testosterone and SHBG.

No known common methodological interferences. A strong interaction with Nandrolone (INN international nonproprietary name, WHO) was found. Do not use samples from patients under Nandrolone treatment. In isolated cases, elevated testosterone levels can be seen in samples from female patients with end stage renal disease (ESRD). Due to the diurnal nature or testosterone concentrations results should be interpreted in conjunction with sampling time (preferably 9am).

The free testosterone calculation used presumes an albumin concentration of 46g/L, and may be adversely affected by low/high albumin concentrations and/or the presence of other binding proteins or steroids.

Total testosterone:

Males:

  • 20 years - 50 years: 8.6-29.0 nmol/L
  • >50 years: 6.7-25.7 nmol/L

Females:

  • 20 years - 50 years: 0.3-1.7 nmol/L
  • >50 years: 0.1-1.4 nmol/L

 

Free testosterone (male):

0.245-0.785 nmol/L

3.3%
49.6%