In hypoparathyroidism, which electrolyte abnormalities are typical?

• A. Hypercalcemia and Hyperphosphatemia
• B. Hypercalcemia and Hypophosphatemia
• C. Hypocalcemia and Hyperphosphatemia
• D. Hypocalcemia and Hypophosphatemia

Answer: (C)

PTH raises blood calcium and lowers phosphate by acting on bone, kidney, and intestine. In hypoparathyroidism, PTH is deficient, so calcium isn’t mobilized and isn’t reabsorbed as effectively, and vitamin D activation decreases, reducing intestinal calcium absorption. At the same time, the lack of PTH’s phosphaturic effect means the kidneys reabsorb more phosphate, raising its level. The combined effect is low calcium with high phosphate, which is the typical electrolyte pattern in hypoparathyroidism.