Cerebellar symptoms heralding bilirubin encephalopathy in Crigler-Najjar syndrome

Area of Science:

• Pediatric Neurology
• Genetic Metabolic Disorders
• Neonatal Jaundice

Background:

• Crigler-Najjar syndrome type I (CN I) is a rare genetic disorder characterized by severe unconjugated hyperbilirubinemia.
• Neurologic deficits, particularly cerebellar symptoms, are known complications but typically manifest later in adolescence or adulthood.
• Bilirubin encephalopathy (kernicterus) results from extreme elevations in unconjugated bilirubin levels.

Observation:

• A 2-year-old female with a confirmed diagnosis of CN I presented with severe cerebellar dysfunction.
• The patient's severe symptoms, including ataxia and hypotonia, were indicative of bilirubin encephalopathy.
• These cerebellar signs were the presenting manifestation of the condition in this young child.

Findings:

• This case demonstrates that severe cerebellar symptoms can be an initial clinical presentation of kernicterus in infants with CN I.
• The patient showed gradual improvement in symptoms with prolonged phototherapy, suggesting a reversible component of bilirubin-induced neurologic damage.
• The early onset of prominent cerebellar signs challenges the typical progression observed in CN I.

Implications:

• Early recognition of cerebellar symptoms in infants with CN I is crucial for prompt diagnosis and management of bilirubin encephalopathy.
• This case underscores the importance of aggressive bilirubin level management from birth in patients with CN I to prevent irreversible neurologic damage.
• Pediatricians and neurologists should consider kernicterus presenting with cerebellar signs in the differential diagnosis of young children with unexplained ataxia and hypotonia, especially those with risk factors for hyperbilirubinemia.