Anti-Rh32 causing severe hemolytic disease of the newborn.

A case of severe hemolytic disease of the newborn due to anti-Rh32 (R = N) is described. The infant recovered without any evidence of neurologic defects, following one exchange transfusion and phototherapy. Using commercial antisera, very weak reactions with anti-Rh2(C) and apparently normal reactions with anti-Rh5(e) were found in the family members carrying the R = N gene complex. However titrations with individual antisera revealed a weakened expression of the Rh5(e) antigen, albeit to a lesser extent than the Rh2(C). It is felt that the serologic findings are due to the fact that the R = N haplotype was paired with an Rh gene carrying normal amounts of Rh4(c) and Rh5(e) antigens. In addition, the maternal anti-Rh32 appears to be pure.