Bilirubin-albumin binding in neonatal salicylate intoxication.

Impaired bilirubin-albumin binding (peroxidase method) was found in serum from a salicylate-toxic neonate. Bilirubin binding improved with serum dilution, indicating weak, competitive salicylate binding. The competitive effect of salicylate was much less than expected from calculations using data from the literature. This occurs because salicylate displaces bilirubin only from the primary bilirubin binding site, and the displaced bilirubin is buffered by secondary bilirubin binding sites. Binding data for salicylate and bilirubin are used to derive guidelines for the clinical management of jaundice in the salicylate-toxic neonate.