What are the symptoms of hypercalcemia? How is this treated?

What are the symptoms of hypercalcemia? How is this treated?

Increases in free ionized calcium can cause gastro-intestinal and neurologic symptoms. The normal level for total serum calcium is 9–10.5 mg/dL (2.2–2.6 mmol/L), and for ionized calcium is 4.5–5.6 mg/dL (1.1–1.4 mmol/L). These values vary slightly among labo-ratories. Gastrointestinal manifestations can be either exci-tatory (nausea and vomiting) or inhibitory (anorexia and constipation). The nervous system is depressed with hypo-tonia, lethargy, and even coma.

Symptomatic hypercalcemia is more likely to be due to malignancy than is asymptomatic hypercalcemia. Malignancy can cause hypercalcemia via PTHrP or by invasion of bone by primary or metastatic tumors. Symptomatic hypercalcemia can also be due to acute vita-min D or oral calcium intoxication. Hypercalcemia is exac-erbated by dehydration.

Long-standing hypercalcemia can cause calcium phos-phate deposition in the kidneys, blood vessels, and other organs. This also happens in renal failure when patients have normal calcium concentrations but elevated phos-phate concentrations.

Treatment of hypercalcemia is somewhat dependent on the cause. Mild hypercalcemia (<12 mg/dL) can be man-aged by hydration. More severe hypercalcemia can be treated acutely with escalating aggressiveness, depending on symptoms and calcium concentrations. First, patients can receive aggressive hydration and forced diuresis with furosemide. Potassium and magnesium are depleted during this treatment and may need to be replaced. Next, patients can receive a bisphosphonate, usually pamidronate. Finally, severe hypercalcemia can be treated with parenteral calcitonin. Hemodialysis or peritoneal dialysis is a useful treatment for severe hypercalcemia in patients with impaired renal function. After acute treat-ment, correctable causes of hypercalcemia can be accom-plished surgically.