Isolated Gonadotropin Deficiency with Response to Luteinizing-Hormone-Releasing Hormone

A 27-year-old man (chromosomes 46 XY) with was not anosmic, and his body build was eunuchoid. Testicular biopsy demonstrated arrested spermatogenesis and Leydig-cell atrophy. Growth hormone, adrenocorticotropin, and thyrotropin responses were found to be intact. Serum follicle-stimulating hormone and luteinizing hormone concentrations, as determined by radioimmunoassay, were undetectable and did not increase after administration of clomiphene citrate. However, the administration of synthetic luteinizing-hormone-releasing hormone increased serum luteinizing hormone and follicle-stimulating hormone concentrations respectively to 22 and 4.1 mIU per milliliter. Our patient thus has a condition for which the term hypothalamic (or tertiary) hypogonadism may be appropriate.