SUPPLEMENTATION OF A STANDARD PRETERM FOR MULA TO IMPROVE CALCIUM ANDPHOSPHORUS SUPPLY OF VLBW AND SMALL-FOR-GESTATIONAL-AGE INFANTS

A standard preterm formula was supplemented with calcium (Ca) and phos phorus (P) (F-CaP: Ca 87 mg/dl, P 43 mg/dl) and compared to the non-su pplemented form (F: Ca 62 mg/dl, P 36 mg/dl). VLBW and small-for-gesta tional-age infants (n=79) were included in the study which was perform ed to look for adverse effects and to decide about a reasonable start and duration of supplementation. In preterm infants with a birth weigh t lower than 1500 g and a body weight of more than 2000 g, the additio nal supplementation with Ca and P lead to a significant higher Ca- and P-retention without further load for the kidney. In addition, preterm infants with a body weight lower than 1500 g also had a better retent ion of Ca and P. Both, F-CaP and F lead to a high urinary excretion of phosphorus, a high renal net acid excretion and a relatively high act ivity of serum alkaline phosphatase. Anthropometric measurements did n ot reveal any evidence for an impaired caloric absorption due to an in creased fecal fat excretion. Hypercalcemia or hyperphosphatemia was no t seen. Hypercalciuria occured in less than 5% of the samples studied. The results of this study indicate that a continuation of the supplem entation with Ca and P is justified in VLBW infants with a body weight of more than 2000 g. There was no evidence for adverse effects of Ca and P supplementation in VLBW infants with a body weight lower than 15 00 g, who might therefore also benefit from supplementation. Further s tudies are necessary to investigate unsatisfactory metabolic condition s of these children e.g. the high renal load.