In Addison disease, which electrolyte abnormality is typical?

In Addison disease, which electrolyte abnormality is typical?

• A. Hypokalemia
• B. Hypernatremia
• C. Hyperkalemia
• D. Hyponatremia

Answer: (C)

Aldosterone deficiency from primary adrenal failure reduces potassium excretion in the distal nephron, so potassium builds up in the blood. This makes hyperkalemia the typical electrolyte abnormality in Addison disease. At the same time, sodium wasting can lead to hyponatremia and volume depletion, but the hallmark electrolyte issue is elevated potassium. Hypernatremia would be unlikely because of salt wasting, and hypokalemia would not occur with aldosterone deficiency.

Aldosterone deficiency from primary adrenal failure reduces potassium excretion in the distal nephron, so potassium builds up in the blood. This makes hyperkalemia the typical electrolyte abnormality in Addison disease. At the same time, sodium wasting can lead to hyponatremia and volume depletion, but the hallmark electrolyte issue is elevated potassium. Hypernatremia would be unlikely because of salt wasting, and hypokalemia would not occur with aldosterone deficiency.