A patient with chronic kidney disease develops hyperkalemia. Which mechanism most directly explains why impaired renal function causes this electrolyte imbalance?

💡 Explanation

Hyperkalemia arises in renal failure because the kidneys' ability to excrete potassium is reduced; therefore, potassium accumulates in the blood. This is due to impaired potassium secretion into the distal tubule and collecting duct, rather than increased reabsorption or altered aldosterone sensitivity.

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