Specificities of calcium-phosphorus metabolism in premature infants fed by different feeding methods
The objective. A complex assessment of calcium-phosphorus metabolic parameters in premature infants with very low and extremely low birth weight depending on the type of feeding and vitamin D supplementation. Patients and methods. Parameters of calcium-phosphosus metabolism were analysed in 285 infants with very low and extremely low birth weight at the 2nd-3rd month of life. Depending on the character of feeding, the examined newborns were divided into 3 groups: group 1 - 89 infants who received formula feeding with a specialised premature baby formula, group 2 - 72 infants who received unfortified native breast milk, group 3 - 124 infants who received breast milk fortified with Pre NAN® FM 85 (Nestle). At the moment of study, all infants irrespective of the feeding type, received a preventive dose of vitamin D 500 IU. Results. Calcium levels were stable irrespective of the character of feeding and remained within the range 2.0-2.51 mmol/L. Phosphorus levels in infants fed with unfortified breast milk were significantly lower (1.38 ± 0.07 mmol/L) than the values of this electrolyte in other studied groups of infants (p < 0.05). Vitamin D metabolite levels were significantly lower in infants receiving unfortified native breast milk (23.00 ± 1.43 ng/ml) as compared with infants receiving an adapted formula (32.00 ± 1.67 ng/ml) or fortified breast milk (35.00 ± 2.09 ng/ml). An increase of the preventive dose of vitamin D to 1000 IU/day did not solve the problem of the arising hypophosphatemia and hypercalciuria. A selective assessment of parathormone levels showed its high values within the reference range. Conclusion. This work has given another proof of the necessity to use breast milk fortifiers or specialised formulas for premature babies as a standard of nutritive support in premature infants with very low or extremely low birth weight.