Racial difference in incidence of ABO hemolytic disease.

In this review of 7,464 consecutive infants born at North Carolina Memorial Hospital, hemolytic disease from ABO incompatibility was found to be two to three times as common in black infants as in white infants. The statistical significance of the difference remained high as more restrictive criteria for ABO hemolytic disease were applied. ABO disease, serious enough to cause an indirect serum bilirubin of 15 mg/100ml or higher, had an incidence in black newborns as great as the incidence of Rh hemolytic disease in whites. In contrast, the general prevalence and severity of hyperbilirubinemia was not found to be higher in black newborns than in white infants. The difference cannot be attributed to differences in the prevalence of ABO blood groups between the two races. Policies of early discharge of newborns could be affected by the finding that ABO erythroblastosis is two to three times as common in black infants as in white infants.