Plasma creatinine in neonates with atresia of the upper gastrointestinal tract.

The human fetus swallows a considerable amount of amniotic fluid which appears to be in balance with the urine output. Since amniotic fluid intake is considered to be compromised in fetuses with atresia of the upper gastrointestinal tract, glomerular function development in such infants may be delayed. Plasma creatinine level determined in 6 neonates with atresia of the upper gastrointestinal tract was similar to the level measured in neonates with lower obstruction, and both groups were within the range of values obtained during other studies in normal newborns. Glomerular functional development is probably not affected in neonates with atresia of the upper gastrointestinal tract.