[Test of pituitary adrenal suppressibility with I.V. dexamethsaone in the diagnosis of Cushing's syndrome (author's transl)].

The authors report a pituitary adrenal suppressibility test, using a 4 h IV infusion of dexamethasone phosphate (4 mg). Plasma cortisol is measured before and at the end of the infusion. The results allow a good discrimination between Cushing's disease (bilateral adrenal hyperplasia: 9 cases) and Cushing's syndrome of tumorous origin (adrenal tumors 7 cases, ectopic ACTH syndrome 3 cases, hypophyseal adenomas 2 cases), only bilateral adrenal hyperplasia cases are lowering significantly.