[Renal tubular function in preterm neonates].
Renal tubular function and functional changes in the preterm neonate are discussed. The proximal tubule has a limited capacity in preserving sodium, leading to a daily sodium need from 3 to 5 mEq/kg/day. The reabsorption of glucose, phosphate and amino acids is also low compared to older children but increases quickly for glucose and phosphate. At the level of the distal tubule, a temporary insensibility for aldosterone leads to a lowered sodium-potassium exchange. A limitation in acid excretion is present. Concentration capacity is restricted with a maximal urine osmolality of 360 mosm/liter. Despite this immature tubular function a glomerulotubular balance exists even in the preterm neonate. The kidneys are thus capable to preserve their homeostatic function.
Afd. Kindergeneeskunde, Erasmus Universiteit, Academisch Ziekenhuis Rotterdam/Sophia, Kinderziekenhuis.
A J
AJ
van der Heijden
E D
ED
Wolff
J
J
Nauta
D000136:Acid-Base Equilibrium; D000450:Aldosterone / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D007671:Kidney Concentrating Ability; D007684:Kidney Tubules / Q000502:physiology*; D010710:Phosphates / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D014882:Water-Electrolyte Balance
D000596:Amino Acids; D010710:Phosphates; D000450:Aldosterone; D012964:Sodium; D005947:Glucose
Renale tubulaire functie bij de preterme neonaat.