The use of a low-dose LHRH test for the distinction of delayed adolescence and isolated gonadotropin deficiency.
In order to evaluate the diagnostic usefulness of a low-dose LHRH test (LHRH HOE 471, bolus injection of 25 micrograms/m2 i.v.), we have reviewed the data of 30 boys with delayed growth and insufficient or lacking sexual development around the age of puberty, and of 8 boys with multiple pituitary hormone deficiencies. In 14 out of 22 boys with delayed adolescence, this diagnosis could be established on the basis of normal LH and FSH results; in 8 boys who also had a delayed but spontaneous pubertal development, gonadotropin response to LHRH was inadequate presumably due to a transiently reduced sensitivity of the "pituitary gonadotroph"; a second LHRH test carried out 12-32 months later revealed normal results. There is some evidence that exogenous or endogenous testosterone is important for the maturation of the adult gonadotropin secretion pattern. Eight patients with isolated true gonadotropin deficiency and all with idiopathic multiple pituitary hormone deficiencies had an insufficient gonadotropin response. This study shows that the low-dose LHRH test allows a good distinction between benign delayed adolescence and gonadotropin deficiency. False-negative results in some boys with delayed adolescence may be due to a decrease of pituitary responsiveness which will normalize with time.
D000293:Adolescent; D005640:Follicle Stimulating Hormone / Q000172:deficiency*; D007987:Gonadotropin-Releasing Hormone; D006801:Humans; D007986:Luteinizing Hormone / Q000172:deficiency*; D008297:Male; D011628:Puberty, Delayed / Q000175:diagnosis*
D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone