Hypothalamic-pituitary-gonadal function in prepubertal boys and girls with chronic renal failure.

Hypothalamic-pituitary-gonadal function was evaluated in 24 prepubertal children with chronic renal failure (CRF). Among the 17 boys, 5 were receiving conservative treatment and four long-term dialysis. Another eight boys were studied 6 months to 3.3 years after renal transplantation; their ages ranged from 5 years 8 months to 15 1/2 years. Among the girls, two patients were receiving conservative treatment and five long-term dialysis; their ages ranged from 3 1/2 years to 11 years 2 months. In boys with CRF, but not in those after transplantation, mean serum follicle-stimulating hormone 60 minutes after administration of gonadotropin releasing hormone (GnRH) was lower than in 18 control prepubertal boys (mean +/- SD: 2.53 +/- 1.34 vs 6.25 +/- 2.84 IU/L, respectively; p < 0.01). Testosterone steroidogenic capacity after 1 week of stimulation with human chorionic gonadotropin and androgen sensitivity (percentage of decrease of serum sex hormone-binding globulin 1 week after intramuscular administration of testosterone enanthate) were normal. In girls, no difference between those with CRF and a control group of 19 girls was found after intravenous administration of GnRH. However, after intramuscular administration of GnRH agonist, serum follicle-stimulating hormone concentration was lower in girls with CRF than in control girls (p < 0.02); six of seven control girls had an increase of serum estradiol to more than 55 pmol/L, whereas three of seven girls with CRF had no response, and serum follicle-stimulating hormone failed to increase after GnRH agonist therapy in two of these patients. We conclude that hypothalamic-pituitary function is not normal in some prepubertal boys and girls with CRF, particularly in those with low serum albumin concentrations. On the other hand, testicular and ovarian steroidogenic capacity is not impaired, and the biologic response to androgens in boys is preserved.