Final answer:
Addison's disease is primarily caused by an autoimmune response where the immune system attacks the adrenal cortex, leading to insufficient cortisol production. Symptoms include fatigue, hyperpigmentation, low blood pressure, and electrolyte imbalances. Cortisol replacement therapy is the usual treatment.
Step-by-step explanation:
Causes and Symptoms of Addison's Disease
Addison's disease, or primary adrenal insufficiency (PAI), is most commonly caused by autoimmune Addison disease (AAD), where the immune system mistakenly attacks the adrenal cortex. This can lead to an insufficiency in cortisol and sometimes mineralocorticoids production. Other causes may include untreated infections like tuberculosis, or issues with the pituitary gland reducing ACTH production, often due to a tumor. Symptoms of Addison's disease include fatigue, hyperpigmentation, hypotension (low blood pressure), hyponatremia (low blood sodium levels), hyperkalemia (high blood potassium levels), and hypoglycemia (low blood sugar levels). These symptoms may manifest alongside general weakness, nausea, weight loss, and salt cravings. Cortisol replacement therapy is the standard treatment to manage the condition.