Assessment of erythrocyte alloimmunization among patients treated at a Brazilian university hospital

• Published in: Hematology, Transfusion and Cell Therapy Transfusion and Cell Therapy, 2024-11, Vol.46 Suppl 5 (Suppl 5), p.S128-S135
• Main Authors: Contelli, Higor Silva, de Oliveira, Mário Cézar, Ido, Aline Akemi Segatti, Francalanci, Elaine Machado, Terra, Patrícia Oliveira da Cunha, Filho, Elmiro Ribeiro, Batistão, Deivid William da Fonseca, Royer, Sabrina
• Format: Article
• Language: English
• Subjects: Antigen-antibody reactions; Blood group antigens; Blood group incompatibility; Erythrocyte transfusion; Original; Transfusion reaction
• ISSN: 2531-1387; 2531-1379; 2531-1387
• DOI: 10.1016/j.htct.2024.04.128

Alloimmunization and transfusion reactions underscore the crucial role of precise immunohematological techniques to enhance safety in transfusion. This study aims to determine the frequency of alloimmunization in patients treated at a Brazilian university hospital, investigate demographic, clinical, and epidemiological characteristics of patients with positive irregular antibody screening, as well as to assess the frequency of erythrocyte antigens and anti-erythrocyte antibodies in the population. This retrospective observational study included all irregular antibody-positive patients treated at the transfusion service of Hospital de Clínicas of the Federal University of Uberlandia between January 2019 and December 2020. Of the 201 irregular antibody-positive patients, alloimmunization was more common in women (64.2%) than in men (35.8%). Blood groups A (39.8%) and O (38.8%), and Rh positive samples (69.1%) predominated, and about half (48.2%) of the patients were transfused for preoperative procedures. The most frequently found clinically significant alloantibodies were anti-D (27.2%), anti-E (15.0%), and anti-Kell (11.5%). Of the patients, 30.6% had multiple antibody associations, with anti-D and anti-C being the most common combination. Erythrocyte immunophenotyping was performed for 76 patients with the most frequent antigens detected being e (100%), c (86.8%), and C (40.8%). Among the 14 pregnant women evaluated, most were multiparous, 85.7% had anti-D as the most prevalent antibody, and had the A-negative blood type (33.3%). Alloantibody screening and identification associated with erythrocyte immunophenotyping are necessary for a better understanding of the alloimmunized population, ensuring greater safety and efficacy of transfusion therapy in the hospital setting.