Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada.
Department of Pediatric Laboratory Medicine, Division of Hematopathology, The Hospital for Sick Children, Toronto, Ontario, Canada.
J Clin Lab Anal. 2023 Sep;37(17-18):e24962. doi: 10.1002/jcla.24962. Epub 2023 Sep 4.
Transfusion-dependent thalassemia patients are at high risk of transfusion-related complications. Yet, there is scanty data on the frequency of transfusion reactions, particularity alloimmunization among pediatric transfusion-dependent thalassemia patients. In addition, there is no consensus on the prophylactic antigen matching for prevention of alloimmunization or the extent of antigen matching for alloimmunized thalassemia patients.
We conducted a retrospective study to assess the frequency and specificity of alloimmunization among pediatric transfusion-dependent thalassemia patients receiving ABO, RhD, and K-matched red blood cell units. In addition, we studied the association between patients' characteristics and alloimmunization. The clinical and transfusion records of transfusion-dependent thalassemia patients followed up at our institution between July 2018 and June 2022 were reviewed.
Ninety-two transfusion-dependent thalassemia patients having mean age of 13.37 years (SD, 5.56) were included in our study. Eight patients (9%) had developed clinically significant alloantibodies; six patients (6%) developed alloantibody against E antigen while two patients (2%) developed more than one alloantibody. Of alloimmunized patients, five patients had received transfusion outside Canada. Patients' sex, age, having a genotype variant, total number, and duration of transfusion received were not associated with the risk of alloimmunization. The transfusion-recipient's diagnosis of β-thalassemia, having developed autoantibody, and history of receiving transfusion outside Canada were associated with alloimmunization.
Blood matching for ABO, RhD, and K antigens resulted in, although not eliminated, lower frequency of alloimmunization than that previously reported among pediatric thalassemia patients. Extending matching to include Rh antigens could further reduce the rate of alloimmunization.
依赖输血的地中海贫血患者有发生输血相关并发症的高风险。然而，关于儿科依赖输血的地中海贫血患者输血反应，特别是同种免疫的频率，数据很少。此外，对于预防同种免疫的抗原匹配预防以及同种免疫的地中海贫血患者的抗原匹配程度，尚无共识。
我们进行了一项回顾性研究，以评估接受 ABO、RhD 和 K 型相合红细胞单位输血的儿科依赖输血的地中海贫血患者同种免疫的频率和特异性。此外，我们还研究了患者特征与同种免疫之间的关系。我们回顾了 2018 年 7 月至 2022 年 6 月在我院接受治疗的依赖输血的地中海贫血患者的临床和输血记录。
本研究共纳入 92 例平均年龄为 13.37 岁（标准差为 5.56）的依赖输血的地中海贫血患者。有 8 例（9%）患者发生了有临床意义的同种抗体；6 例（6%）患者产生了针对 E 抗原的同种抗体，而 2 例（2%）患者产生了超过一种的同种抗体。在发生同种免疫的患者中，有 5 例患者在加拿大以外的地方接受过输血。患者的性别、年龄、基因型变异、接受的总输血次数和持续时间与发生同种免疫的风险无关。受血者β-地中海贫血的诊断、自身抗体的产生以及在加拿大以外接受输血的历史与同种免疫有关。
尽管 ABO、RhD 和 K 抗原的血液匹配降低了同种免疫的频率，但并未消除，其频率低于以前报道的儿科地中海贫血患者。将匹配扩展到包括 Rh 抗原可能会进一步降低同种免疫的发生率。
