Hypoparathyroidism is associated with which electrolyte pattern?

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

Answer: (C)

The key idea is how parathyroid hormone (PTH) controls calcium and phosphate. PTH raises serum calcium and lowers serum phosphate. It does this by increasing bone resorption, increasing calcium reabsorption in the kidneys, and stimulating active vitamin D to boost intestinal calcium absorption. It also promotes phosphate excretion by the kidneys. When PTH is deficient, calcium levels fall because there’s less calcium being mobilized and absorbed, while phosphate isn’t excreted as effectively, so phosphate rises. That combination—low calcium with high phosphate—fits hypoparathyroidism best.