Kernicteric findings at autopsy in two sick near term infants

We present two near term sick infants with unanticipated kernicterus noted at autopsy, which developed in the absence of hemolysis and at serum bilirubin levels that would not have been considered neurotoxic. The kernicterus evolved in the context of known experimental conditions that would have favored the passage of unbound bilirubin across a disrupted blood brain barrier with injury of specific neurons. The relationship between serum bilirubin concentrations and the development of kernicterus in the term infant is complex. While a distinct link between the maximum recorded level of serum bilirubin and the occurrence of kernicterus is apparent with hemolytic disease of the newborn (most often due to Rh isoimmunization), the risk is less clear in markedly jaundiced babies without hemolytic disease. Moreover, in some instances, clinical and pathologic kernicterus has been observed in premature infants without hemolytic disease and with low bilirubin levels.7,8 The management of jaundice in sick term newborns is a challenge to clinicians visa vis the risks of undertreatment and overtreatment. To underscore the complexity of this important clinical relationship, we present two patients of unanticipated kernicterus noted at autopsy which evolved in two sick infants, one near term and the other term, in the absence of overt hemolysis and at serum bilirubin concentrations that usually would have not been considered neurotoxic.