Emergency Management Of Hypercalcemia In Primary Hyperparathyroidism

This aims at correction of hypercalcemia in mild cases of hyperparathyroidism, asymptomatic hypercalcemia in elderly patients, and in poor surgical risks. In such cases, the intake of calcium should be restricted to 200 mg or less by avoiding dairy products. Serum calcium can be lowered by the regular administration of potassium phosphate 1- 2g daily. The patient should be carefully followed up for detecting metastatic calcification. Peptic ulceration should be managed on its own merits.

Emergency management of hypercalcemia: Severe hypercalcemia is a life-threatening emergency. Measure to correct dehydration and enhance calcium loss in urine are started without delay. Intravenous infusion of 2-3 liter of 0.9% saline over a period of 6 hours and administration of furosemide 80 mg 2-4 hourly help to correct dehydration, induce dieresis, and eliminate calcium in urine.

Other methods to lower serum calcium

1. Salmon calcitonin is given intravenously or subcutaneously in a dose of 4 MRC units/Kg every 12 hours. If the response is inadequate, the dose can be increased to 8 MRC units/Kg.
2. Intravenous infusion of phosphate: The solution contains 11.5g Na₂HPO₄ and 2.58g KH₂PO₄/liter. Over a period of 4 hours, 500 ml of this solution is infused. Further doses are given depending on the clinical response. Phosphate promotes the deposition of calcium in bones.
3. Rapid intravenous infusion of disodium acetate (200 mg/Kg) over 30- 60 minutes lowers serum calcium. Overdose should be avoided, since it may produce hypocalcemic tetany and coagulopathies.
4. Physical methods such as hemodialysis or peritoneal dialysis using calcium-free dialysis fluids help in removing calcium.
5. Hypercalcemia caused by conditions other than hyperparathyroidism may respond to corticosteroids.
6. Mithramycin in doses of 50 mg/Kg/day intravenously has been tried effectively in some cases.

Differential diagnosis: Primary hyperparathyroidism has to be distinguished from secondary hyperparathyroidism and all causes of hypercalcemia. In secondary hyperparathyroidism, though PTH levels are high, serum calcium values are not elevated. Common causes of hypercalcemia are disseminated malignancy involveing bone, hypervitaminosis D, thyrotoxicosis, Addison’s disease, milk-alkali syndrome and prolonged immobilization. Rarely hypervitaminosis A, sarcoidosis, multiple myeloma and thiazide drugs may be the cause of hypercalcemia. Sometimes hypercalcemia may run in families (benign familial hypercalcemia). Idiopathic hypercalcemia is a rare disorder of infancy, often associated with congenital cardiovascular defects.