Department of Pathology and Internal Medicine, College of Medicine, Ohio State University, Columbus, Ohio.
Transfusion. 2015 Jan;55(1):18-24. doi: 10.1111/trf.12762. Epub 2014 Jun 23.
Thrombotic thrombocytopenic purpura (TTP) requires immediate treatment with plasma exchange (PE) to prevent disease mortality and/or morbidity. Frequently, PE is initiated before blood sample is collected to confirm ADAMTS13 deficiency. However, the effect of PE treatments on the evaluation of ADAMTS13 is uncertain. Moreover, the pertinence of ADAMTS13 activity during PE therapy to prediction of treatment outcomes is unclear. Thus, clarification of the diagnostic and prognostic values of ADAMTS13 activity obtained during PE treatment is an unmet clinical need.
A total of 212 sequential samples were obtained during the course of daily PE treatment from 19 patients with acquired TTP. ADAMTS13 activity levels were determined in these longitudinal samples for analysis.
After the initial three daily PE procedures, the sensitivities of ADAMTS13 activity in diagnosis of TTP (<10%) were 89, 83, and 78%, respectively. To determine prognostic value, patients with (n = 7) and without (n = 12) a recovery of ADAMTS13 activity to more than 10% within seven sessions of daily PE treatment were compared. Recovery of ADAMTS13 activity to more than 10% within 7 days is significantly associated with a timely achievement of clinical response (p < 0.01). In contrast, the patients without more than 10% ADAMTS13 within 1 week appear at risk for worse treatment outcomes manifested as TTP exacerbation, treatment refractoriness, or death.
The data suggest that ADAMTS13 activities measured during the initial period of PE therapy offer both diagnostic and prognostic values in acquired TTP.
血栓性血小板减少性紫癜（TTP）需要立即进行血浆置换（PE）治疗，以预防疾病的死亡率和/或发病率。通常，在采集血液样本以确认 ADAMTS13 缺乏症之前，就开始进行 PE。然而，PE 治疗对 ADAMTS13 评估的影响尚不确定。此外，在 PE 治疗期间 ADAMTS13 活性与治疗结果预测的相关性也不清楚。因此，阐明在 PE 治疗过程中获得的 ADAMTS13 活性的诊断和预后价值是临床尚未满足的需求。
从 19 例获得性 TTP 患者的日常 PE 治疗过程中总共获得了 212 个连续样本。对这些纵向样本中的 ADAMTS13 活性水平进行了测定。
在最初的 3 个每日 PE 治疗程序后，ADAMTS13 活性对 TTP 的诊断（<10%）的灵敏度分别为 89%、83%和 78%。为了确定预后价值，将 ADAMTS13 活性恢复至每日 PE 治疗 7 个疗程后超过 10%的患者（n=7）与未恢复的患者（n=12）进行了比较。7 天内 ADAMTS13 活性恢复至 10%以上与及时达到临床反应显著相关（p<0.01）。相比之下，在 1 周内 ADAMTS13 活性未超过 10%的患者似乎有发生 TTP 恶化、治疗抵抗或死亡等不良治疗结局的风险。
数据表明，在获得性 TTP 中，PE 治疗初始期间测量的 ADAMTS13 活性既具有诊断价值，也具有预后价值。
