Diagnostic significance of free salivary testosterone measurement using a direct luminescence immunoassay in healthy men and in patients with disorders of androgenic status.
The accurate measurement of testosterone remains a challenge. The determination of the blood testosterone concentrations in serum by conventional immunoassays is inaccurate in men and even more so in females and children. A new luminescence enzyme immunoassay (LIA) has been developed and validated. The high analytical (8.7 pmol/L) and functional (17.3 pmol/L) sensitivity allows the quantification of the very low concentration in saliva, as well as in serum, after 1/40 dilution. This study measured salivary testosterone levels and compared the results with the free levels calculated from total testosterone and sex hormone-binding globulin in eugonadal and hypogonadal men. Salivary testosterone concentrations in healthy men in morning hours were 369 pmol/L (mean), range 263-544 pmol/L, which was statistically significantly higher than that in men with androgen deficiency, 215 pmol/L (mean), range 51-249 pmol/L. Repetitive determination of free testosterone concentrations in saliva (once a week for 5 weeks) showed high stability of results over time, with coefficient of variation 9% (range 5-23%). In this study we showed that free salivary testosterone levels in morning samples correlated well with calculated free testosterone in blood, both in healthy men (R = 0.754, P = 0.001), and in patients with androgen deficiency (R = 0.889, P = 0.0001), though in cases with very low testosterone, salivary concentrations were systematically higher than calculated free testosterone levels in blood.
Goncharov
Nikolai
N
National Center of Endocrinology, Dm. Ulyanova Street, 11, 117036, Moscow, Russia. GoncharovN@endocrincentr.ru
Katsya
Gulinara
G
Dobracheva
Anna
A
Nizhnik
Alexander
A
Kolesnikova
Galina
G
Herbst
Victor
V
Westermann
Jürgen
J
D000328:Adult; D000728:Androgens / Q000172:deficiency*; D005858:Germany; D006801:Humans; D007118:Immunoassay; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D012463:Saliva / Q000378:metabolism*; D013739:Testosterone / Q000032:analysis*
D000728:Androgens; D013739:Testosterone