Frequency of maternal red blood cell alloantibodies and clinical utility of antibody screening in Abuja, Nigeria.

BACKGROUND

Pregnancy causes immunisation when the fetal red cells, possessing a paternal antigen foreign to the mother, enter the maternal circulation, resulting in the production of alloantibodies. Maternal allo-immunisation, also known as iso-immunization, occurs when a woman's immune system is sensitised to foreign erythrocyte surface antigens, stimulating the production of immunoglobulin G (IgG) antibodies. This study was carried out to determine the frequency of maternal Red blood cell alloantibodies in Gwarimpa General Hospital, FCT, Abuja, and to evaluate the clinical utility of antibody screening.

METHODS

This was a prospective cross-sectional study involving 250 pregnant women aged 16-45 years recruited from an antenatal care clinic within the period of 6 months. Serum grouping and ABO blood grouping was done using the tube method. Indirect antibody testing was used for antibody screening, using DiaCeLL I + II + III Screening Cells (DiaMed AG, Switzerland), while indirect antiglobulin test was used for antibody identification on all positive cell samples using DiaPanel cells (DiaMed AG, Switzerland).

RESULT: The result of the study showed that 29.8 % of the study participants have had two pregnancies; only 1.2 % have had greater than 4 pregnancies. The most frequently occurring irregular antibody detected was anti-E; 3 (1.2 %), followed by anti-K; 2 (0.8 %), then anti-C and anti-Jsb (0.4 % respectively). Three of the samples had mixed field reactions, while two could not be identified using the panel cell. A blind anti-globulin cross-match carried out on 250 samples revealed that 5 (2.0 %) were incompatible with blood from the same blood group, while 245 (98.0 %) were compatible with blood from the same blood group.

CONCLUSION

Efficiency of the screening method was 48.6 % while the percentage safety of the Antibody screening method was 41.6 %. The immune form of anti-E is able to cause a mild to moderate haemolytic disease of the newborn.