Primary hyperaldosteronism is most characteristically described by which finding?

• A. Hyperkalemia with high renin.
• B. Hypertension resistant to therapy with hypokalemia and low renin.
• C. Hypotension with hyponatremia.
• D. Hypernatremia with edema.

Answer: (B)

Primary hyperaldosteronism causes too much aldosterone, which drives sodium and water reabsorption in the distal nephron. This expands extracellular volume and raises blood pressure, often in a way that is resistant to standard antihypertensive therapy. At the same time, excess aldosterone increases potassium and hydrogen ion loss in the collecting duct, leading to hypokalemia and often metabolic alkalosis. Because the aldosterone production is autonomous, the renin–angiotensin system is suppressed, so renin levels are low. This combination—refractory hypertension with hypokalemia and low renin—is the classic pattern for primary hyperaldosteronism. The other choices describe scenarios that don’t fit this physiologic profile: high renin or hyperkalemia points to secondary causes or different disorders; hypotension or edema without the characteristic electrolyte pattern is not typical.