Paediatrics: Bilirubin encephalopathy (kernicterus)

Bilirubin encephalopathy (kernicterus)

A clinical syndrome resulting from the development of excessive neuro-toxic unconjugated bilirubin levels. Toxic levels lead to selective damage of the cerebellum, basal ganglia, and brainstem auditory pathways. It may occur in the healthy neonate if serum bilirubin is >360µmol/L , but usually only occurs at significantly higher serum levels (>430µmol/L after 48hr of life) unless:

• Infant is <24hr old.

• Infant is preterm.

• Infant is severely ill (any cause).

• Infant is acidotic.

• Caused by iso-immunization haemolytic disease.

• Reduced albumin binding caused by drugs or hypoalbuminanaemia.

Presentation

• Lethargy progressing to hypertonia then hypotonia.

• Poor feeding.

• Fever.

• High-pitched cry.

• Opisthotonos.

• Seizures and coma.

Main differential diagnosis is meningoencephalitis/sepsis. Neonatal tetany may also present with opisthotonos.

Treatment

• Supportive (likely to require full intensive care).

• Urgent reduction of serum bilirubin by intensive phototherapy and exchange transfusion.

• Give IV immunoglobulin.

• Treat underlying cause.

Prognosis

Majority survives, but there is a high risk of athetoid cerebral palsy, deaf-ness, and low IQ.