In order to determine the cause of hypocortisolism & hypercortisolism this assay is carried out. In a patient with hypocortisolism, Primary adrenal insufficiency is indicated by an elevated ACTH. Secondary adrenal insufficiency are found to have normal levels from pituitary or hypothalamic causes. A suppressed value is consistent with cortisol producing adrenal adenoma, exogenous corticosteroid use and primary adrenal micronodular among the patients with hypercortisolism.
