Which disease results from autoimmune destruction of the adrenal cortex leading to insufficient cortisol and aldosterone?

• A. Cushing's syndrome
• B. Addison's disease
• C. Hypothyroidism
• D. SIADH

Answer: (B)

Autoimmune destruction of the adrenal cortex causes primary adrenal insufficiency, leading to deficits of both cortisol and aldosterone. When cortisol is low, you get fatigue, weakness, hypoglycemia, and low blood pressure. With aldosterone deficiency, there is salt wasting, hyponatremia, hyperkalemia, and dehydration, contributing to hypotension. The loss of cortisol feedback raises ACTH levels, and hyperpigmentation can occur in some cases. This combination specifically matches Addison’s disease. The other conditions involve different hormonal problems: Cushing’s has too much cortisol, hypothyroidism involves low thyroid hormone, and SIADH causes water retention and hyponatremia from excess ADH rather than adrenal failure. Treatment centers on replacing cortisol and, if needed, mineralocorticoids.