Abstract: Objective To report two cases of hemolytic anemia caused by intravenous immunoglobulin (IVIG) in the newborn. Methods ABO and Rh blood grouping, three tests for hemolytic disease of the newborn, unexpected antibodies identification, and crossmatching were performed by serologic methods. Results Case 1: a neonate with severe HDN caused by anti-C and anti-D. After administration of IVIG, a IgG-A was detected in the neonate's elution fluid. Case 2: a neonate had hyperbilirubinemia due to infection. After administration of IVIG, DAT was weakly positive and IgG-A was detected in the elution fluid. The hemoglobin rose after stopped IVIG and transfused with O-type washed RBCs. Conclusion IVIG may cause hemolytic anemia in newborn. If it happens, the IVIG should be stopped and O-type washed RBCs is feasible for transfusion after compatible crossmatching.

Key words: Intravenous immunoglobulin, IgG anti-A, IgG anti-B, Hemolytic disease of the fetus and newborn, Crossmatch