Symptomatic hypercalcemia of immobilization in a patient with end-stage renal disease

The phenomenon of hypercalcemia in immobilization is well known, but there is limited awareness of the potential for this complication in patients with end-stage renal disease (ESRD) on maintenance hemodialysis with reduced capacity for disposition of calcium. We describe such a patient who showed a calcemic response to just 3 days of immobilization in the setting of an acute illness marked by coma. Despite intensive initial therapy for hypercalcemia, including withdrawal of all calcium products and daily hemodialysis treatments using low calcium baths, her serum calcium rose to 14.0 mg/dL during the hospitalization; this metabolic abnormality appeared to perpetuate her stuporous state. Mobilization as an outpatient was the most effective therapy. Extensive testing was performed to rule out other causes for this patient's hypercalcemia. Greater recognition of acute hypercalcemia in patients with ESRD immobilized by various illnesses would preclude unnecessarily expensive and invasive testing for other causes of hypercalcemia.