CONGENITAL HEMOLYTIC DISEASE RESULTING FROM A-O ISOIMMUNIZATION

Abstract

Three instances of fatal hemolytic disease of the newborn have been observed in group A infants born of Rh positive mothers belonging to group O. Markedly elevated anti A agglutinins were demonstrated in the mother's serum following delivery of the child. (1:10,120 in Case 1, 1:5,000 in Case 2, and 1:6,000 in Case 3. All these titers fell within three weeks.) All infants were Rh positive and no Rh or Hr antibodies were found in the mothers' serum. Jaundice became apparent in all infants within 24 hours of birth. There was a moderate anemia, and varying numbers of nucleated red blood cells were found in the peripheral blood. One infant died on the third day of life, the second on the fifth, and the third on the sixth. In all cases the typical changes of hemolytic disease of the newborn were present at autopsy and in all extensive kernicterus of the basal ganglia, hippocampal nuclei, periventricular pontine nuclei, cerebellar dentate nuclei and medullary olives were found. The finding of free circulating antibodies in the infant's blood obtained postmortem is of particular interest. These anti A agglutinins were active only in albumin-plasma dilutions. The retention of the agglutinating property of this antibody in both infant and mother even after addition with A and B blood group specific Witebsky substances indicate that it is probably an immune antibody. It is believed that A-O isoimmunization has been proved in these three cases.