ABO hemolytic disease of the newborn. A retrospective analysis of 254 cases.

ABO hemolytic disease of the newborn is the single most common cause of neonatal jaundice, with an incidence of 54.4 per 1,000 births; it occurs almost exclusively in infants of groups A or B having mothers of group O. Previous studies have shown a poor correlation between serologic tests on cord blood and clinical course in affected infants. In a retrospective analysis of 254 cases of ABO hemolytic disease of the newborn the relation of laboratory parameters to incidence and severity of jaundice was studied. Sixty-five per cent of the infants who had positive direct antiglobulin tests experienced jaundice, compared with approximately 35% of control infants or infants who had ABO hemolytic disease of the newborn with negative direct antiglobulin test results. Infants who had ABO hemolytic disease of the newborn with positive direct antiglobulin test results also had greater severity of jaundice than control infants or infants who had ABO hemolytic disease of the newborn with negative direct antiglobulin test results (P less than .0001). Thus, the direct antiglobulin test is a good screening test for ABO hemolytic disease of the newborn. Sex, race, gravidity, birth weight, and blood type of the infant did not have significant relationships to clinical outcome. The combined results of the direct antiglobulin test and the strength of reaction in a heat eluate may be of use in prognosis; although differences were not significant, infants who had stronger eluates had higher bilirubin values and were more likely to require therapy. Serologic analysis of cord blood can be useful in the early detection of infants having the risk of severe jaundice.