Predictive and diagnostic measures for kernicterus spectrum disorder: a prospective cohort study.

BACKGROUND: Kernicterus spectrum disorder (KSD) resulting from neonatal hyperbilirubinemia remains a common cause of cerebral palsy worldwide. This 12-month prospective cohort study followed neonates with hyperbilirubinemia to determine which clinical measures best predict KSD.

METHODS: The study enrolled neonates ≥35 weeks gestation with total serum bilirubin (TSB) ≥ 20 mg/dl admitted to Aminu Kano Hospital, Nigeria. Clinical measures included brain MRI, TSB, modified bilirubin-induced neurologic dysfunction (BIND-M), Barry-Albright Dystonia scale (BAD), auditory brainstem response (ABR), and the modified KSD toolkit. MRI signal alteration of the globus pallidus was scored using the Hyperbilirubinemia Imaging Rating Tool (HIRT).

RESULTS: Of 25 neonates enrolled, 13/25 completed 12-month follow-up and six developed KSD. Neonatal BIND-M ≥ 3 was 100% sensitive and 83% specific for KSD. Neonatal ABR was 83% specific and sensitive for KSD. Neonatal HIRT score of 2 was 67% sensitive and 75% specific for KSD; this increased to 100% specificity and sensitivity at 12 months. BAD ≥ 2 was 100% specific for KSD at 3-12 months, with 50-100% sensitivity.

CONCLUSIONS: Neonatal MRIs do not reliably predict KSD. BIND-M is an excellent screening tool for KSD, while the BAD or HIRT score at 3 or 12 months can confirm KSD, allowing for early diagnosis and intervention.

IMPACT: The first prospective study of children with acute bilirubin encephalopathy evaluating brain MRI findings over the first year of life. Neonatal MRI is not a reliable predictor of kernicterus spectrum disorders (KSD). Brain MRI at 3 or 12 months can confirm KSD. The modified BIND scale obtained at admission for neonatal hyperbilirubinemia is a valuable screening tool to assess risk for developing KSD. The Barry Albright Dystonia scale and brain MRI can be used to establish a diagnosis of KSD in at-risk infants as early as 3 months.