A term female baby was delivered via emergency cesarian to a 28-year-old woman. The baby was pale and limp at delivery and required resuscitation. On examination, there was generalized rash, edema and hepatosplenomegaly. The mother has no history of previous pregnancy or abortions and this is her first pregnancy. Her antenatal history was uneventful with all investigations within normal limits and blood group of O positive. Investigations of the baby reveal anemia, increased reticulocyte count, thrombocytopenia, elevated bilirubin levels and blood group of B positive.

Polychromatic cells, spherocytes and nucleated RBCs were present in the peripheral smear. What is the probable diagnosis? What other investigation can show the likely cause? Source: McDonnell M, Hannam S, Devane SP . Arch Dis Child Fetal Neonatal Ed 1998;78:3 F220-F221 doi:10.1136/fn.78.3.F220