An Early (Sixth-Hour) Serum Bilirubin Measurement Is Useful in Predicting the Development of Significant Hyperbilirubinemia and Severe ABO Hemolytic Disease in a Selective High-Risk Population of Newborns With ABO Incompatibility

Abstract

The reticulocyte count, a positive direct antiglobulin test, and the presence of a sibling with neonatal jaundice were determined to be the good predictors for the development of significant hyperbilirubinemia and severe hemolytic disease of the newborn. A serum bilirubin measurement and the use of the critical bilirubin levels of 4 mg/dL and 6 mg/dL at the sixth hour of life will predict nearly all newborns who will have significant hyperbilirubinemia and those who will develop severe hemolytic disease of the newborn, respectively. An hour (age)-specific percentile-based nomogram can be used to predict which newborn is at high risk (> or =90th percentile), intermediate risk (35th-90th percentiles), and low risk (<35th percentile) for developing significant hyperbilirubinemia. The 35th and 90th percentile tracks, approximating the serum bilirubin levels of 3.3 mg/dL and 6.5 mg/dL at the sixth hour of life, respectively, can be used as safe risk demarcators in deciding about the time of discharge of ABO-incompatible newborns from the hospital.