Hypogonadotropic hypogonadism from osteopetrosis.

A 47-year-old man with acquired hypogonadism of at least 15 years' duration was successfully treated with chorionic gonadotropin. Endocrine studies performed before and two months after discontinuation of gonadotropin therapy showed a decrease in serum testosterone level without secondary rise in serum gonadotropins. Testing for the release of other pituitary hormones, TSH, ACTH, HGH and prolactin, showed normal results. Radiographic evaluation of the sella turcica demonstrated a decrease in sellar size with increase in bone density. A bone survey showed that the increase in bone density was generalized. Thickening and disorganization of the bony trabeculae was seen in a biopsy of bone from the iliac crest. The patient described here represents a transitional variety between the infantile and adult forms of osteopetrosis. It is suggested that encroachment of the pituitary gland by the osteopetrotic bone produced the hypogonadotropic hypogonadism of this patient.