Which electrolyte abnormality is commonly seen in chronic kidney disease?

• A. Hypokalemia
• B. Hyperkalemia
• C. Hypercalcemia
• D. Hypophosphatemia

Answer: (B)

Potassium balance is controlled mainly by the kidneys, so when kidney function declines, the ability to excrete potassium diminishes. In chronic kidney disease, reduced filtration and impaired distal potassium secretion lead to accumulation of potassium in the blood, especially as the disease progresses. This makes hyperkalemia the most common and clinically important electrolyte abnormality in CKD, since high potassium can cause dangerous heart rhythm problems. By contrast, hypokalemia would require ongoing potassium loss or low intake, which isn’t typical in CKD. Hypercalcemia isn’t the usual pattern because CKD tends to cause low or normal calcium with phosphate retention driving secondary hyperparathyroidism, and hypophosphatemia is uncommon since phosphate excretion is impaired leading to phosphate buildup rather than depletion.