A fatal case of acute hemolytic transfusion reaction caused by anti-Wra: case report and review of the literature

Haemolytic transfusion reactions caused by non-ABO red cell antibodies reported to the Norwegian Haemovigilance System 2004-2020

BACKGROUND AND OBJECTIVES

The aim of this study was to analyse the reports received in the Norwegian Haemovigilance System from 2004 to 2020 on acute and delayed haemolytic transfusion reactions caused by non-ABO red cell antibodies.

MATERIALS AND METHODS

Antibody specificity, clinical symptoms and outcomes were included when available.

RESULTS

After transfusion of 3.7 million red cell concentrates, reports on 78 cases of haemolytic transfusion reactions caused by non-ABO red cell antibodies were received, corresponding to an incidence of 1 in 47,000 transfused red cell concentrates. There were 30 acute and 48 delayed haemolytic transfusion reactions. A total of 113 red cell antibodies were found: 82 alloantibodies, 6 autoantibodies and 25 cases where the antibody specificity could not be determined. Two fatalities occurred: one caused by anti-Wra and one caused by an unidentified red cell antibody. The most frequently reported antibody specificities were those in the Rh and Kidd blood group systems, representing 24% and 14%, respectively, of all the antibodies identified. In six cases, errors occurred, leading to the issuing of blood units without the required phenotype match.

CONCLUSIONS

Despite the possible underreporting, the low number of serious haemolytic transfusion reactions reflects an adequate pre-transfusion practice by the Norwegian blood banks.

Acute hemolytic reaction by anti-Wra: Case report and review of the hemovigilance database of a tertiary care hospital

Wra is the most common LIA in white population. The incidence of Wra antigen in Spanish population has been estimated to be 1 in 785 in blood donors, while anti-Wra was found in 2.7 % and 3.6 % of healthy donors and transfused patients respectively. Severe, even fatal hemolytic transfusion reactions and hemolytic disease of the newborn caused by anti-Wra have been reported. Since the reagent red blood cells used for antibody screening usually lack Wra antigen, the anti-Wra is not detected and hemolytic reaction could occur if transfusion is performed by type and screen approach. We report an acute hemolytic reaction due to anti-Wra in a patient with negative antibody screening. We have also reviewed the records of the hospital hemovigilance database in order to collect the previous hemolytic cases due to anti-Wra. During a 21-year period 461,539 red blood cell units have been transfused to 81,614 patients in our hospital. Alloimmnunization was detected in 3840 patients (0.83 %) and anti-Wra was detected in 22 patients (1/3709), 10 of whom had other alloantibodies, and only in 1 occasion (this case) has been implicated in mild hemolytic acute transfusion reaction. In our experience, the risk of fatal hemolytic reaction due to LIA in hospitals with blood services using the type and screen policy is extremely low.