Hemolytic Disease of the Newborn Due to Anti-A1

Abstract

Abstract 1. The authors report clinical, hematological and serological data in a case of A1 iso-sensitization of pregnancy. 2. The mother’s serum displayed immune characters specific to A1 cells immediately after delivery. On the 24th day post partum the specificity extended to A2 cells. 3. The disease exhibited by the infant was very mildly hemolytic. It was marked by a deep jaundice, repeated alimentary vomiting and a progressive state of drowsiness. There was no anemia. The direct anti-globulin test was negative. 4. It is shown that the mildness of the hemolytic process in cases of placental transfer of immune anti-A or anti-B into the incompatible A or B fetus is probably dependent upon a peculiar "resistance" of the fetal cells. This may be demonstrated in vivo and in vitro. In the present case replacement transfusion with A1adult blood resulted in its in vivo sensitization, detectable by the antiglobulin test and eventually leading to hemolytic anemia.