Development of serum hexosaminidase activity in infants.

Serum activity of hexosaminidases A and B has been measured to identify patients with Tay-Sachs and Sandhoff diseases, and may also be influenced by other clinical conditions including neonatal necrotizing enterocolitis. We have characterized the normal developmental pattern of hexosaminidase activity in serum by measuring this enzyme activity in 61 neonates of 27-40 weeks gestation who were followed from birth to age 4-8 weeks. Total serum hexosaminidase activity significantly increased with postnatal and gestational age, and with initiation of enteral feeding. We conclude that serum hexosaminidase activity in infants with clinical conditions that may influence serum activity of this enzyme must be compared to that in normal infants of similar gestational and postnatal ages.