Identification of alloantibodies and their associations: Balance sheet of 3 years at the Regional Center of Blood Transfusion in Rabat/Morocco and difficult in transfusion management

: Red blood cell immunization can lead to delays or even an impasse in a transfusion.

Objective: Determine the specificities of the most common of alloantibodies and their associations to correct management of red blood cell transfused.

Methods: A retrospective study between 2013 and 2015 in immunohematology laboratories at the Blood Transfusion Center of Rabat in Morocco. The following data were studied: frequency, specificities of alloantibodies, blood group involved in alloimmunization and difficult of management of transfusion in case with association of alloantibodies.

Results: Five hundred of alloantibodies were identified in 425 people (372 patients/pregnant women and 53 blood donors). The alloantibodies were directed against the following antigen: RH1 (50.8 %), RH3 (11.4 %), KEL 1 (8.2 %), RH2 (7.6 %), RH4 (4.6 %), MNS1 (4 %), MNS3 (2.6 %), Jka (2.4 %) and Fya (2.2 %). Only one alloantibody was identified in 85 % of cases. In 15 %, at least, two alloantibodies were found. The most common associations were directed against: anti-(D+C) (25), anti-(E+K) (4), anti-(E+c) (3) and anti-(D+C+E) (3). The rhesus system is the most involved in alloimmunization. Frequency of specific associations of alloantibodies was identified: Fya-/Jkb- (18.23 %), Fyb-/Jkb- (11.7 %), Jka-/S- (8.70 %), Jka-/Fyb- (5.20 %), Fyb-/s- (3.40 %) and Fyb-/Jkb-/s- (0.85 %).

Conclusions: Red blood cell immunization is a serious problem in transfused patients. This study proves the data of literature, the interest of using RH-Kel1 red cell units compatibles among women in age to procreate and for the transfused patients to reduce the rate of immunization. Associations of antibodies with low frequency suggest a promotion of donation.