Elevated ACTH

Increased concentration of adrenocorticotropic hormone (ACTH) above the established reference range, taking into account the normal diurnal variation (typically 10-60 pg/mL).

Causes

• Primary adrenal insufficiency: Addison's disease (high ACTH, low cortisol)

• ACTH-dependent hypercortisolism

  • Cushing's disease (pituitary ACTH-producing adenoma)

  • Ectopic ACTH syndrome

• Adrenal insufficiency following glucocorticoid withdrawal (during recovery phase)

• Congenital adrenal hyperplasia

• Adrenal resistance to ACTH (rare)