Department of Hematology and Clinical Immunology, Yokohama City University School of Medicine, Yokohama, Japan.
Department of Transfusion and Cell Therapy, Yokohama City University Hospital, Yokohama, Japan.
Hematology. 2021 Dec;26(1):835-839. doi: 10.1080/16078454.2021.1986654.
Passenger lymphocyte syndrome (PLS) is a specific subtype of graft versus host disease (GVHD) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) characterized by an immune-mediated hemolysis caused by donor-derived B cells. However, precise nature of PLS has not been well characterized due to its rarity. We herein report two cases of PLS following ABO-incompatible HSCT whose clinical course and dynamics of anti-ABO allo-antibody and blood type conversion were closely examined. Both cases demonstrated acute hemolysis upon engraftment, and the presence of high titer allo-antibody against recipients' red blood cells (RBCs) helped us to reach the diagnosis of PLS. Hemolysis in both cases showed spontaneous improvement with prednisolone and supportive therapy including transfusion and fluid support. In one case with blood type O, the patient recursively developed PLS in the second and the third HSCT from ABO-mismatch donors, leading to a hypothesis that original blood type O may serve as a background for acute elevation of serum anti-ABO antibody and therefore a risk for developing PLS in multiple ABO-incompatible HSCTs. When hemolysis is noted following ABO-incompatible HSCTs, PLS should be considered and measurement of anti-ABO antibodies is warranted.
移植物抗宿主病（GVHD）是异基因造血干细胞移植（allo-HSCT）后一种特定的疾病亚型，其特征是供体来源的 B 细胞引起免疫介导的溶血性贫血。然而，由于其罕见性，PLS 的精确性质尚未得到很好的描述。我们在此报告了两例 ABO 不相容 HSCT 后发生的 PLS，对其临床病程和抗 ABO 同种异体抗体的动态变化及血型转换进行了密切检查。这两例患者在植入后均出现急性溶血性贫血，而存在针对受者红细胞（RBC）的高滴度同种异体抗体有助于我们诊断为 PLS。这两例患者的溶血性贫血均自发改善，采用泼尼松龙和输血、补液等支持治疗。在一例血型为 O 的患者中，患者在第二次和第三次来自 ABO 不合供体的 HSCT 中递归性地发生 PLS，提示原始血型 O 可能作为血清抗 ABO 抗体急性升高的背景，因此在多次 ABO 不相容 HSCT 中发生 PLS 的风险增加。当 ABO 不相容 HSCT 后出现溶血性贫血时，应考虑 PLS，并应测量抗 ABO 抗体。
