[The clinical significance of the radioimmunological determination of plasma ACTH (author's transl)].

The clinical significance of the direct determination of plasma ACTH was investigated in healthy persons and in patients with primary or secondary adrenocortical insufficiency, with Cushing's syndrome or with acromegaly. The sensitivity of the radioimmunological method facilitated the detection of diurnal changes in plasma ACTH in healthy subjects and of variations in plasma ACTH after the administration of dexamethasone and glucagon. The determination of plasma ACTH appears to be a useful procedure of diagnostic value in patients suffering from primary adrenal insufficiency accompanied by high concentrations of plasma ACTH. However, in patients suffering from Cushing's syndrome or secondary adrenocortical insufficiency it is still essential to carry out the dexamethasone suppression test or the metopiron test, respectively.