Introdução do NAT no Brazil: algumas considerações adicionais

Impact on patient of the detection of weakly expressed RhD antigens in blood donors

“…Rh, the most complex blood group system, has the highest clinical importance after the ABO group. 6 , 7 The D antigen, found in Rh-positive individuals, is the most important in the system as it is the most immunogenic. 7 , 8 Therefore, given the risk of alloimmunization, RhD-positive red blood cells must not be transfused to RhD-negative patients except in emergencies involving massive hemorrhage when RhD-negative units are not available.…”

“… 7 , 8 Therefore, given the risk of alloimmunization, RhD-positive red blood cells must not be transfused to RhD-negative patients except in emergencies involving massive hemorrhage when RhD-negative units are not available. 7 …”

“… 9 Amino acid substitution in the intracellular or transmembrane segment of the RhD protein leads to weakening of the D antigen expression in the membrane of red blood cells resulting in a weak D phenotype. 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 Hence, weak D testing must always be performed in blood donors with absent reactivity in the screening test, and if the results are weakly positive, the donors must be classified as RhD-positive in order to prevent anti-D alloimmunization in RhD-negative patients who receive transfusions of packed red blood cells. 6 , 7 , 8 , 10 …”