[Urinary calcium/creatinine, phosphate/creatinine, magnesium/creatinine and Sulkowicz test in the second morning urine sample in neonates and infants].

The aim of the paper was to determine the values of the 5th and 95th percentiles of Ca/Cr, P/Cr and Mg/Cr, ratios in the second-morning urine samples in healthy neonates and infants. The collected Ca/Cr ratios were correlated with the results of Sulkowicz test performed on the same urine sample. The tests were done on the group of 30 neonates and 43 infants. The comparison of the 95th percentiles in the individual ratios in tested groups showed low values in the early newborn, distinctive increase in the first half followed by the decrease in the second half of the first year of live. There was no correlation found between the Ca/Cr ratios and the results of Sulkowicz tests.