HEMOLYTIC DISEASE OF THE NEWBORN DUE TO UNRECOGNISED ANTI-Kpa ANTIBODY

Background: Kpa occurs in less than 2 percent of the Caucasian population. Antibody to this low frequency antigen causes mild to moderate delayed hemolytic transfusion reactions and hemolytic disease of fetus and newborn. Screening for antibodies to low frequency antigens such as Kpa is not routine, so sensitization is more difficult to diagnose. Case report: We present a case of hemolytic disease of the newborn due to anti-Kpa antibody unrecognised during regular considered first pregnancy. Results: Newborn, blood group 0 RhD positive, has been diagnosed with neonatal jaundice and positive direct antiglobuline test. Mother's screening test for irregular antibodies was negative three times during pregnancy. Elution was negative with screening red blood cells, but in identification using gel technology with cell's panels, anti-Kpa has been identified. Conclusion: Screening for antibodies to low frequency antigens such as Kpa is not routine, so immunisation to low incidence antigens is hard to diagnose, but very important. This case should alert us that there really is potential of antibodies to low incidence antigens to cause severe reactions. Keywords: Kell blood group system; Hemolytic disease of newborn; red cell alloimmunisation