Calcium supplement increase on the second day of sequential two day leukapheresis

Peripheral blood progenitor cells are collected effectively by leukapheresis of a large volume of peripheral blood. However, protection must be taken for patients or donors from hypocalcemia due to continuous infusion of citric acid. We found a tendency for hypocalcemic symptoms in patients or donors to occur more often on the second day than the first day of the sequential 2 days of leukapheresis. The doses of calcium gluconate supplement and the acid citrate dextrose-A solution administration significantly increased on the second day compared to that of the first day. The blood levels of c-terminal parathormone (PTH), phosphorus, and alkaline phosphatase did not show remarkably abnormal change. However, urine calcium excretion just after leukapheresis was higher than in the period before or after leukapheresis compared to the phosphorus or creatinine excretion. These findings indicate that the cause of a higher tendency to hypocalcemic symptoms on the second day of the sequential 2 days of leukapheresis is due to the higher metabolism of calcium being excreted in the urine during leukapheresis.