Lethal hyperparathyroid crisis: hazards of phosphate administration.

Two patients with hypercalcemia crisis and parathyroid adenoma died as a result of pulmonary insufficiency. The administration of phosphate is believed to have contributed to the deaths, since the pulmonary problems appeared when the blood [Ca] X [PO4] product rose and extensive metastatic calcification was present in the pulmonary alveolar lining. The use of phosphates as calcium-lowering agents in hypercalcemia is discouraged, because phosphate appears to lower calcium levels only by intravascular precipitation.