Diagnosis of Bilirubin Encephalopathy in Preterm Infants with Dyskinetic Cerebral Palsy

Introduction: Very preterm infants are susceptible to bilirubin neurotoxicity, the signs of which are unclear during early infancy. We investigated children born preterm and later diagnosed with bilirubin encephalopathy (BE) to gain insights into accurate early diagnosis. Methods: We identified 93 children born preterm and clinically diagnosed with BE who visited our hospital between 2006 and 2018. Perinatal history, findings of auditory brainstem response (ABR), brain magnetic resonance imaging (MRI), and functional outcomes were investigated retrospectively based on chart review. Results: The mean gestational age and birth weights were 27.2 weeks and 991 g, respectively. During the neonatal period, only 3% (2/71) had exchange transfusions, and none were diagnosed with acute BE. ABR was abnormal in 64% (51/80), but the majority (34/51) required no hearing aids. Brain MRI taken between 6 and 18 months of age revealed bilateral T2 hyperintensity of the globi pallidi in 91% (60/66); subsequently, the rate decreased with age. Functional communication outcomes were markedly superior to gross motor and hand function outcomes. Conclusion: For early diagnosis of BE, brain MRI is recommended at a corrected age of between 6 and 18 months, especially for those with abnormal ABR during early infancy, and even with no apparent history of marked neonatal hyperbilirubinemia.