RESUMEN
Basal and stimulatory tests of FSH, LH and PRL are reported in three cases of hypogonadism-anosmia syndrome (Maestre-Kallmann-De Morsier syndrome), two of whom were brothers. Basal FSH levels were low (mean = 1.7 mU/ml) and did not respond to the first acute stimulation with intravenous LRH (x = 2.3 mU/ml), but after intramuscular LRH, 500 microgram/day for 10 days, a clear-cut response was noted in two patients (from a mean of 7.8 mU/ml to 16.8 mU/ml), while the other patient continued without response. Low basal LH levels (mean 1.8 mU/ml) responded poorly to the first LRH stimulation (mean 4.6 mU/ml), while after intramuscular LRH for 10 days there was a marked increase in all three cases (mean 29.7 mU/ml). In no case was there a response to clomiphene. With regard to PRL, all cases had a clear response to TRH, although it was subnormal in two of them. Opposite results were obtained in one case of Klinefelter's syndrome, namely, elevated basal PRL levels (44 ng/ml) with an exaggerated response to TRH. Chlorpromazine administration caused an elevation of PRL to 43 and 30 ng/ml, respectively, in the two patients with a subnormal response to TRH, while the third case responded less than to TRH. In conclusion, the response to TRH of FSH and LH with lack of response to clomiphene supports the hypothalamic nature of the hypogonadism, while the response of PRL to both TRH and chlorpromazine, along with the normal levels of the remaining pituitary hormones (ACTH, TSH and STH) demonstrate the selectivity of the hypothalamic lesion whereby only gonadotrophin control is impaired.