Acute Renal Failure in Neonates and Infants

Acute renal failure (ARF) in neonates and infants represents a distinct diagnostic and therapeutic problem, as compared with ARF in older children and adults. Among children it is found most often in infancy and in those under three years of age (3, 4, 8, 9, 13). The causes of ARF in younger children differ from those observed in older children. The functional demands on the immature kidney of neonates and infants are greater than in adults, as the metabolic rate of the infant related to body weight is considerably greater. Insensible water loss is five times greater, energy demands in relation to body weight about three times greater, and normal fluid intake four times greater. Another important predisposing factor is the absence of normal thirst control in infants who are unable to take up more water spontaneously during fluid depletion or sodium overload. It is therefore not surprising that renal vascular causes of ARF are especially prominent in neonates (1, 2, 11) and that dehydration leading to acute tubular necrosis is prevalent in infants (3, 4, 5, 7, 9, 14). The hemolytic uremic syndrome (HUS) represents another specific cause of ARF in infants, and according to many authors is the most common cause (3, 8, 9, 13, 15).