Addison's disease is a hormone deficiency (not enough hormone) caused by damage to the outer layer of the adrenal gland (the part known as the adrenal cortex).
The adrenal glands are small hormone-secreting organs located on top of each kidney. They consist of the outer portion (called the cortex) and the inner portion (called the medulla). The cortex produces 3 types of hormones: glucocorticoid hormones, mineralocorticoid hormones, and sex hormones.
Addison's disease results from damage to the adrenal cortex. The damage causes decreased production of the hormones produced by the cortex. This damage may be caused by the following:
Risk factors for the autoimmune type of Addison's disease include other autoimmune diseases:
These may be caused by certain genetic defects.