Disorders of growth hormone and corticotropin regulation in patients with empty sella

Endocrine functions in 7 cases of primary empty sella were studied. No clinical features of endocrine disturbances were apparent. Urinary excretion of gonadotropins, and thyroid and adrenal functions were normal. Plasma human growth hormone (HGH) concentration was also normal but did not increase after insulin induced hypoglycemia in 4 patients, after arginine in one, and after a glucose load in 6. Urinary excretion of 17 hydroxycorticosteroids (17 OHCS) increased normally in all patients after metyrapone administration, while plasma 17 OHCS did not increase in 3 subjects after insulin induced hypoglycemia or in one after lysine vasopressin. Two patients showed exaggerated responses to lysine vasopressin. These results indicate an impairment of the hypothalamic HGH and corticotropin regulation in patients with empty sella. Since in chromophobe adenomas comparable changes were seen, the differential diagnosis between empty sella and chromophobe adenoma is impossible on the basis of endocrinological data alone. The only reliable diagnostic method is accurate radiological study including air contrast tomoencephalography.