Disorders of bilirubin binding to albumin and bilirubin-induced neurologic dysfunction

Area of Science:

• Neonatal Neurology
• Bilirubin Metabolism
• Neurotoxicology

Background:

• Bilirubin-induced neurologic dysfunction (BIND) encompasses subtle neurotoxic disorders in newborns.
• Elevated unconjugated bilirubin and impaired bilirubin binding to albumin increase BIND risk.
• Disorders affecting albumin binding include low albumin, reduced binding capacity/affinity, and displacing substances.

Purpose of the Study:

• To explore serum unbound bilirubin (UB) as a marker for bilirubin binding to albumin.
• To understand the relationship between bilirubin binding disorders and neurological injury in infants, particularly preterm infants.

Main Methods:

• The study reviews existing literature on bilirubin neurotoxicity and binding disorders.
• Analysis focuses on the role of serum unbound bilirubin (UB) as a potential clinical marker.
• Clinical signs of neurological injury in relation to bilirubin levels and binding are examined.

Main Results:

• Serum unbound bilirubin (UB) concentration is proposed as an ideal marker reflecting bilirubin binding to albumin.
• Kernicterus, a severe form of BIND, is characterized by motor impairments and specific neuroimaging/evoked potential findings.
• Preterm infants may exhibit acute bilirubin encephalopathy at lower bilirubin levels due to impaired binding.

Conclusions:

• Disorders in bilirubin binding to albumin are critical in neonatal bilirubin neurotoxicity.
• Serum unbound bilirubin (UB) shows promise as a marker for assessing neurotoxicity risk.
• Understanding these binding dynamics is crucial for managing bilirubin-related neurological injury in vulnerable infants, especially preterm neonates.