What are the different categories of adrenal insufficiency and their pathophysiology?
Primary: Inability of adrenal gland to excrete sufficient steroid hormones from the adrenal cortex. This results in high ACTH and low cortisol, aldosterone and dehydroepiandrosterone (DHEA).
Secondary: Reduced Adrenocorticotrophic Hormone (ACTH) from the anterior pituitary.
Tertiary: Reduced Corticotrophin Releasing Hormone (CRH) from the hypothalamus.
