Increased urine calcium during hyperalimentation in quadriplegia: report of 2 cases.

Two acute quadriplegic adolescent boys with hypercalcemia had large increases in urine calcium during calcium-free, or nearly free, intravenous hyperalimentation. The calcium which spilled in the urine proved to be of endogenous origin since it was accompanied by proportional amounts of hydroxyproline. To limit the endogenous bone losses during hyperalimentation, it is recommended that calcium in an amount equal to that loss be added to the perfusate so that only exogenous calcium is spilled in the urine.