In a consecutive series of 83 Rh-isoimmunized infants, 7 had significantly elevated levels (greater than 1.0 mg./100 ml.) of direct bilirubin in the cord blood and developed obvious biliary obstruction. In no instance was a low concentration of direct bilirubin in the cord blood associated with the development of this condition. Serially determined electrophoretic separations of the serum proteins in 6 of the 7 patients revealed patterns not unlike those seen in the normal infant.
In exchange transfusions calculated to remove 85 per cent of the infant's blood, the total bilirubin concentration of the serum was reduced 30 to 50 per cent in infants with and in those without biliary obstruction. However, for the purpose of maintaining the total bilirubin concentration below "critical" levels, it was found that exchange therapy is less efficient, from a temporal standpoint, in infants whose hemolytic disease is complicated by biliary obstruction.
The cause of intrahepatic biliary obstruction is discussed and the prognostic value of the concentration of direct bilirubin in the cord blood of erythroblastotic infants is stressed.