Cord blood bilirubin level as an early predictor of neonatal hyperbilirubinemia - A hospital-based prospective study

Background: Neonatal hyperbilirubinemia, a condition characterized by elevated bilirubin level in blood, is a common, complicated, and controversial clinical problem. The American Academy of Pediatrics (AAP) recommends a follow-up visit, after 2 to 3 days of birth, to detect significant jaundice in all newborns discharged within 48 hours of delivery. The present study was carried out to evaluate cord blood bilirubin levels as an early predictor of neonatal hyperbilirubinemia. Methods: The study group consisted of 500 term, appropriate for gestational age (AGA) neonates with an Apgar score of ≥7. Total bilirubin of ≥15 mg/dL was defined as significant hyperbilirubinemia. Umbilical cord serum bilirubin (UCSB) was estimated and followed up daily for evidence of neonatal hyperbilirubinemia up to 5 postnatal days. Prevalence of hyperbilirubinemia was found to be 14% in the study population. In case of clinical jaundice presenting before 5 days, serum bilirubin level was estimated on the day of detection. Values of bilirubin on fifth day were related with that of cord blood bilirubin. Blood groups of both mothers and newborns were evaluated. Direct Coomb's test was done in presence of ABO incompatibility. Data were analyzed using chi-square, and receiver operating characteristics (ROC) curve. Results: Mean UCSB was reported to be 1.56 ± 0.70 mg/dL. There was a significant association between route of delivery, birth order, and hyperbilirubinemia requiring phototherapy (P<.005). Using UCSB level of 31.9 mg/dL, hyperbilirubinemia could be predicted with sensitivity of 90% and specificity of 82.55% and positive predictive value of 45.65% and negative predictive value of 98.07%. There was no significant association found between the mothers' blood groups and increased risk of hyperbilirubinemia in neonates in this study. Conclusion: This study suggests that the measurement of UCSB is a useful tool for early prediction of the subsequent course of jaundice in healthy term newborns in Indian population. It may help to improve the management of newborns.