Plasma ACTH measurements are used in the differential diagnosis of pituitary insufficiency and treatment of certain disorders of the adrenal glands, such as Cushing syndrome and adrenocortical insufficiency (Addison's disease).
Measurement of ACTH is most commonly performed using immunoassay methods that employ radioisotopic (RIA) or chemiluminescent (CIA) modes of detection. Both RIA and CIA analytical principles have demonstrated the ability to distinguish between low-normal and suppressed ACTH secretion from the pituitary.
