Treatment of severe hypercalcemia in primary hyperparathyroidism with aminopropylidene diphosphonate

Objective: To test the clinical usefulness and potency for decreasing plasma calcium concentration of an intravenously administered diphosphonate (aminopropylide diphosphonate [APD]) in a patient with hypercalcemic crisis secondary to primary hyperparathyroidism, unresponsive to hydration and furosemide, and who was ineligible for surgery because of cardiac conduction defects. Design: Case report. Setting: Referred care setting. Intervention: The patient received APD 15 mg/d, dissolved in 100 mL of isotonic NaCl 0.9% and infused in one hour. Main Outcome Measure: Plasma calcium concentration. Results: The patient's plasma calcium concentration fell considerably in a few days. The concomitant decrease in urinary calcium excretion indicates that this fall is caused by a decreased entry of calcium to the extracellular fluid and not to increased renal calcium excretion. After nine days, a parathyroid adenoma was removed; plasma calcium concentration remained normal during the following three years. Conclusions: APD is a useful adjunct to medical therapy in patients with hypercalcemic crisis secondary to primary hyperparathyroidism.