Immobilization-related hypercalcemia after renal failure in burn injury.

Objective: To describe a patient with hypercalcemia presumably due to immobilization in the setting of burn injury and acute renal failure.

Methods: We present a case report of a man who sustained a severe burn injury and then had renal failure and hypercalcemia. An additional series of patients with burns and immobilization was assessed for the presence of hypercalcemia.

Results: In a 43-year-old man with burns on 65% of his body surface area, acute renal failure developed. Renal function failed to return, and he continued to require hemodialysis. Because of the severity and extensiveness of his burns, he remained immobilized. Serum calcium levels were low during the early part of the hospitalization. On the 57th day, generalized tonic-clonic seizures developed, and he was found to have a high ionized calcium level (1.41 mmol/L). Low values were recorded for intact parathyroid hormone (2 pg/mL), 25-hydroxyvitamin D (5 ng/mL), and 1,25-dihydroxyvitamin D (4 pg/mL). Persistent and recurrent hypercalcemia eventually responded to pamidronate and calcitonin. Other than immobilization, we could identify no predisposing factors such as confounding illnesses or medications that could have caused the hypercalcemia. A review of serum ionized calcium levels in 50 consecutive patients admitted to a burn unit and immobilized for at least 20 days failed to reveal any episodes of persistent hypercalcemia.

Conclusion: In our patient with burns and renal failure, symptomatic hypercalcemia was most likely attributable to prolonged immobilization. As patients with catastrophic illnesses survive for longer periods, additional problems such as hypercalcemia from immobilization may occur.