URINARY N-ACETYL-BETA-D-GLUCOSAMINIDASE EXCRETION IN TERM AND PRETERMNEONATES

Urinary N-acetyl-beta-D-glucosaminidase (NAG) excretion was measured i n term and preterm neonates on days 1, 4, 7, 14 and 28 of life. Urinar y NAG showed a peak level on day 4 or 7 in these infants. In addition, it tended to be higher with the degree of prematurity. In sick preter ms who were depressed at birth and had respiratory failure, the NAG ac tivity was further elevated during the first 2 weeks, suggesting the p resence of renal tubular injury in this period. These observations thu s suggest that urinary NAG may be a sensitive measure of renal maturat ion or damage in neonates.