Divisions of Laboratory Medicine and Hematology, Center for Cancer and Blood Disorders, Sheikh Zayed Campus for Advanced Children's Medicine, Children's National Hospital, District of Columbia, Washington.
Departments of Pediatrics and Pathology, George Washington University School of Medicine and Health Sciences, District of Columbia, Washington.
Pediatr Blood Cancer. 2021 Aug;68(8):e29082. doi: 10.1002/pbc.29082. Epub 2021 Apr 26.
T-antigen activation usually occurs upon red blood cell (RBC) membrane cryptantigen exposure due to bacterial enzymes. Although uncommon, the condition is probably underrecognized. There is concern about hemolysis after plasma and plasma-containing platelet transfusions due to naturally occurring anti-T antibody in healthy blood donors. However, experts have debated the extent and severity of clinical hemolysis due to anti-T.
We retrospectively identified patients who tested positive for polyagglutination with Arachis hypogea and Glycine max lectins from 2008 to 2019. The records of the patients were reviewed to determine clinical symptoms, laboratory evidence of hemolysis, need for transfusion, and clinical outcomes.
Ten patients were identified. At diagnosis, all were anemic and four had thrombocytopenia. Severe Streptococcus pneumoniae infection affected seven patients; one died. Seven of 10 patients (70%) had laboratory evidence of hemolysis. Peripheral blood smear findings in six patients included RBC agglutination and changes suggesting hemolysis (spherocytes and schistocytes), but three had unremarkable RBC morphology. Four patients required plasma or platelet transfusions; all survived to discharge.
T-antigen activation is a rare entity. Most patients diagnosed at our hospital had hemolytic anemia and severe pneumococcal infection. Hemoglobin decreased after plasma and platelet transfusions in all patients assessed, but these transfusions were necessary to support treatment. RBCs were given to maintain appropriate hemoglobin levels.
T 抗原激活通常发生在红细胞（RBC）膜隐抗原暴露于细菌酶时。尽管不常见，但这种情况可能未被识别。由于健康献血者中天然存在抗 T 抗体，人们担心血浆和含血小板的血浆输注后会发生溶血。然而，专家们对由于抗 T 引起的溶血的程度和严重程度存在争议。
我们回顾性地确定了 2008 年至 2019 年用花生凝集素和大豆凝集素检测呈多凝集阳性的患者。对患者的记录进行了审查，以确定临床症状、溶血的实验室证据、输血的需求和临床结果。
确定了 10 名患者。诊断时，所有患者均贫血，4 例血小板减少。严重的肺炎链球菌感染影响了 7 名患者；1 人死亡。10 名患者中有 7 名（70%）有溶血的实验室证据。6 名患者的外周血涂片发现包括 RBC 聚集和提示溶血的变化（球形红细胞和裂体细胞），但 3 名患者的 RBC 形态无明显异常。4 名患者需要血浆或血小板输血；所有患者均存活至出院。
T 抗原激活是一种罕见的现象。我们医院诊断的大多数患者均患有溶血性贫血和严重的肺炎球菌感染。所有评估患者的血红蛋白在输注血浆和血小板后均下降，但这些输血是支持治疗所必需的。给予 RBC 以维持适当的血红蛋白水平。
