Free androgen index is superior to total testosterone for short-term assessment of the gonadal axis after renal transplantation.
OBJECTIVE
Recent studies have assessed gonadal function in association with different immunosuppressive drugs in transplanted patients mainly relying on the measurement of total testosterone. It is the aim of this study to assess the short-term changes of the hypothalamic-pituitary-gonadal axis following renal transplantation using the free androgen index (FAI).


METHODS
The sequential changes in total testosterone, sex hormone-binding globulin (SHBG), gonadotropin and prolactin concentrations were measured in 22 male patients before and after 1-3 days, and 1, 2 and 3 weeks following renal transplantation.


RESULTS
Total testosterone and SHBG concentrations dropped significantly after transplantation (total testosterone: baseline: 15.2 +/- 1.6 nmol/l vs. 1 week: 7.9 +/- 0.8 nmol/l vs. 2 weeks: 9.8 +/- 0.9 nmol/l, SHBG: baseline: 29.9 +/- 3.2 nmol/l vs. 1 week: 19.9 +/- 2.1 nmol/l, 2 weeks: 18.9 +/- 2.4 nmol/l, p < 0.01). FAI decreased significantly after day 1-3 returning to values near baseline thereafter (baseline: 60 +/- 9% vs. day 1-3: 38 +/- 6%, 2 weeks: 61 +/- 7%; p < 0.01). There was a significant positive correlation between FAI and renal function.


CONCLUSIONS
Measurement of the free androgen index is superior to total testosterone for assessment of the pituitary-gonadal axis in the first weeks after renal transplantation.
Reinhardt
Walter
W
Department of Nephrology, School of Medicine, University of Duisburg-Essen, Essen, Germany.
Patschan
Daniel
D
Pietruck
Frank
F
Philipp
Thomas
T
Janssen
Onno E
OE
Mann
Klaus
K
Jockenhövel
Friedrich
F
Witzke
Oliver
O
D000328:Adult; D000728:Androgens / Q000097:blood*; D006801:Humans; D016030:Kidney Transplantation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010902:Pituitary Gland / Q000502:physiology*; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013737:Testis / Q000502:physiology*; D013739:Testosterone / Q000097:blood*; D013997:Time Factors
D000728:Androgens; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone