Hypercalcemia in 25 OH D3 treated patients receiving a calcium exchange resin

Seven patients with advanced renal failure, six of whom were dialysed, received a cation exchange resin in the calcium cycle because of severe hyperkalemia, together with their usual preventive treatment of renal osteodystrophy, including 25 hydroxycholecalciferol. Hypercalcemia developed in four subjects within less than thirty days and disappeared within four days following the withdrawal of the resin. Patients who exhibited hypercalcemia had higher calcium intake, lower predialysis blood calcium and higher PTH values before introduction of the treatment. Three of the four hypercalcemic patients were diabetics. It is therefore advised to frequently monitor blood calcium when using calcium exchange resin in patients treated with vitamin D analogs.