1 - Serviço de Imuno-hemoterapia, Hospital Dona Estefânia, Unidade Local de Saúde de São José.
2 - Unidade de Pediatria Hematológica, Hospital Dona Estefânia, Unidade Local de Saúde de São José.
3 - Laboratório de Imuno-hematologia, Centro do Sangue e Transplantação de Lisboa, Instituto Português do Sangue e da Transplantação, Lisboa, Portugal.
- 33º Congresso Regional da Sociedade Internacional de Transfusão de Sangue (ISBT) em Gotemburgo, Suécia.
- Publicado sob a forma de resumo na revista Vox Sanguinis
- Premiado com a Harold Gunson Fellowship
Background: Despite its benefits, RBC transfusion for sickle cell disease (SCD) carries a heightened risk of alloimmunization in patients.
Aims: Analize allo and autoantibody prevalence in pediatric SCD patients.
Methods: Retrospective analysis of medical records of SCD patients admitted to the pediatric hematology department at Hospital Dona Estefânia, from January 2020 to December 2021.
Results: Forty SCD patients were included. Twenty-four patients received 139 transfusions. All patients received extended matched RBCs. Three patients developed four de novo alloantibodies (anti-Jka, anti-M, anti-Lua, and anti-Jsa), yielding an 8% alloimmunization prevalence at a rate of 3.0 alloantibodies per 100 transfusions. All alloimmunized patients had autoantibodies.
Summary/Conclusions: The low alloimmunization prevalence in our study may be due to the exclusive use of extended matched RBC transfusions, aligning with our Institutional Policy. The higher-than-expected alloimmunization rate may be due to biased patient selection, emphasizing the role of inflammation in alloimmunization. All alloimmunized patients presented concomitant autoantibodies, which have also been identified as an important risk factor. Considering potential antibody evanescence post-primary response, establishing a centralized registry of IAS results could be crucial in preventing delayed hemolytic transfusion reactions.
Palavras Chave: Alloimmunization; Sickle Cell Disease, Transfusion