Haemolytic disease of the newborn due to anti K antibodies in a kell negative mother

الملخص EN

A very rare case of haemolytic disease of the newborn due to anti k antibodies is reported.

The mother of this newborn belonged to an extremely rare phenotype where all Kell locus gene products were absent thus making her capable of producing antibodies against all Kell blood group antigens.

This extremely rare situation makes it impossible to get compatible blood of the same blood group.

Bahrain Med Bull 1996;18(1): Alloimmune haemolytic anaemia of the newborn (erythroblasto-sis foetalis) is a disease of the foetus and newborn caused mostly by the D antigen of the Rh blood group system1 .

Very rarely erythroblastosis is due to anti k which is part of the Kell blood group system2-4.

We report a case of erythroblastosis foetalis due to anti k antibodies produced in a mother who is negative for almost all Kell blood group antigens.

THE CASE A 28 years old Bahraini woman admitted at 29 weeks gestation with vaginal bleeding and lower abdominal pain.

This was her second pregnancy.

Her first pregnancy had resulted in full term normal delivery.

She was on regular checkup at the antenatal clinic.

Her blood group was O,Rh positive and she was negative for VDRL, sickling and G6PD deficiency.

No screening for antibodies was done during her antenatal checkups.

After admission her bleeding continued and her haemoglobin dropped from 10.5 g/dl to 8.3g/dl.

Screening for antibodies was done and indirect Coombs results showed 4+ positivity with antibody titre of 1:2056.

The patient was found to be negative for K,k,Kpa,Kpb antigens and her husband of consanguineous marriage was blood group A,Rh positive, k and Kpb positive and negative for K and Kpa.

The antibodies in the mother were thus of anti k and Kpb in nature.