Objective: To investigate the clinical characteristics, treatment and prognosis of children with acquired thrombotic thrombocytopenic purpura (TTP). Methods: The clinical manifestations, laboratory examination, treatment and prognosis of 5 children with acquired TTP hospitalized in Beijing Children's Hospital, Capital Medical University from January 2016 to July 2019 were analyzed retrospectively. Results: There were 5 children with acquired TTP including 2 males and 3 females, with the onset age of 8.9(0.8-14.5) years, while 11 children with TTP in the same period. Thrombocytopenia and microangiopathic hemolytic anemia were found in all 5 patients. Only one patient had typical pentalogy of TTP, 3 patients had nervous system symptoms and 3 patients had fever, while renal impairment was relatively rare (1 case). Laboratory examination showed severe thrombocytopenia (7(4-14) ×109/L) and low level of hemoglobin (70(58-100)g/L) in all 5 children. Blood biochemical examination showed that total bilirubin (mainly indirect bilirubin) increased in 3 patients, lactate dehydrogenase increased in 5 patients, and urea nitrogen increased in 1 patient. Bone marrow smear showed megakaryocyte did not decrease. Plasma ADAMTS13 activity was 0 in all 5 patients while ADAMTS13 inhibitor was positive in 4 patients and negative in 1 patient. All 5 children received glucocorticoid therapy, rituximab was added in the early stage of the disease, and 3 children received plasma exchange. The time of platelet recovery to normal was 19 (9-29) days. One child had TTP recurrence after 9 months of treatment. The condition was stable after being treated with glucocorticoid and rituximab again. This case was finally diagnosed as systemic lupus erythematosus after more than 3 years followed up. By December 1, 2020, the follow-up time was 24(16-57) months.The clinical symptoms of all patients disappeared and the platelet level was stable at 159(125-269) ×109/L. Conclusions: Childhood acquired TTP is relatively rare, which can occur in all age groups. The clinical manifestations are mainly thrombocytopenia and microangiopathic hemolytic anemia, the plasma ADAMTS 13 activity and inhibitor test are helpful for the diagnosis of acquired TTP. Plasma exchange and rituximab are effective treatment. This disease requires long-term follow-up.
目的： 探讨儿童获得性血栓性血小板减少性紫癜（aTTP）的临床特点、治疗情况以及预后。 方法： 回顾性病例总结，以2016年1月至2019年7月于首都医科大学附属北京儿童医院住院治疗的5例aTTP患儿为研究对象，分析患儿临床表现、实验室检查、治疗及预后情况。 结果： 纳入5例aTTP患儿，占同期血栓性血小板减少性紫癜患儿的5/11，其中男2例、女3例，发病年龄8.9（0.8~14.5）岁。5例患儿均存在血小板减少和微血管病性溶血性贫血，仅1例存在经典五联征，3例患儿伴神经系统症状，3例有发热，而肾功能损伤相对少见（1例）。5例患儿均存在重度血小板减低［7（4~14）×109/L］及血红蛋白下降［70（58~100）g/L］；血生化检查示3例总胆红素水平升高，均以间接胆红素升高为主，5例乳酸脱氢酶水平均升高，1例尿素氮升高。骨髓穿刺提示巨核细胞数目不低。ADAMTS13活性检查均为0，4例ADAMTS13抑制物阳性，1例为阴性。5例患儿均接受糖皮质激素治疗，并且在疾病早期应用利妥昔单抗治疗，3例患儿接受血浆置换。5例患儿血小板恢复正常的时间为开始治疗后的19（9~29）d。1例患儿在治疗9个月后出现复发，再次予糖皮质激素及利妥昔单抗治疗后病情稳定，随访3年以上确诊为系统性红斑狼疮。截至2020年12月1日，随访24（16~57）个月，5例患儿临床症状消失，未次随访血小板计数为159（125~269）×109/L。 结论： 儿童aTTP患者较为少见，各年龄段均有发病，临床表现以血小板减少及微血管病性溶血为主，血浆ADAMTS13活性及抑制物检测有助于aTTP的诊断。血浆置换及利妥昔单抗治疗有效，该病需长期随诊监测。.