Which laboratory finding is consistent with hyperaldosteronism?

Which laboratory finding is consistent with hyperaldosteronism?

• A. Arterial pH of 7.48
• B. Potassium 5.0
• C. Calcium 9.0
• D. Sodium 135

Answer: (A)

Hyperaldosteronism drives sodium reabsorption in the distal nephron while increasing potassium and hydrogen ion secretion. The loss of hydrogen ions raises blood pH, producing metabolic alkalosis, and the loss of potassium leads to hypokalemia. Among the lab findings, an arterial pH of 7.48 indicates alkalemia consistent with metabolic alkalosis from excess aldosterone. The potassium value of 5.0 is not low enough to show the expected hypokalemia, the sodium of 135 is not clearly elevated to reflect hypernatremia, and the calcium is normal. So the alkalemia best reflects the effect of excess aldosterone on acid–base balance.

Hyperaldosteronism drives sodium reabsorption in the distal nephron while increasing potassium and hydrogen ion secretion. The loss of hydrogen ions raises blood pH, producing metabolic alkalosis, and the loss of potassium leads to hypokalemia. Among the lab findings, an arterial pH of 7.48 indicates alkalemia consistent with metabolic alkalosis from excess aldosterone. The potassium value of 5.0 is not low enough to show the expected hypokalemia, the sodium of 135 is not clearly elevated to reflect hypernatremia, and the calcium is normal. So the alkalemia best reflects the effect of excess aldosterone on acid–base balance.