Delayed hypercalcemia with acute renal failure associated with nontraumatic rhabdomyolysis

Delayed hypercalcemia developed in two patients with acute renal failure and rhabdomyolysis. In patient 1, the hypercalcemia appeared 14 days after the beginning of the diuretic phase of the illness and was associated with severe diastolic hypertension and soft-tissue calcification, including the lungs and skeletal muscles. The blood levels of 25-hydroxyvitamin D (25OHD3) were elevated during the hypercalcemia and decreased to normal when the patient became normocalcemic. In patient 2, the hypercalcemia occurred 55 days after the start of the diuretic phase and at a time when renal function was normal.