Internal Medicine Department, Nantes University Hospital, Nantes, France.
Onco-Hematology and Internal Medicine Department, Departmental Hospital Center, La Roche-Sur-Yon, France.
PLoS One. 2021 Nov 19;16(11):e0260196. doi: 10.1371/journal.pone.0260196. eCollection 2021.
Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare life-threatening thrombotic microangiopathy requiring urgent therapeutic plasma exchange (TPE). However, the exact impact of a slight delay in TPE initiation on the subsequent patients' outcome is still controversial.
We aimed to study the frequency, short-term neurological consequences, and determinants of diagnostic delay in iTTP.
We conducted a retrospective monocentric study including patients with a first acute episode of iTTP (2005-2020) classified into 2 groups: delayed (>24h from first hospital visit, group 1) and immediate diagnosis (≤24h, group 2).
Among 42 evaluated patients, 38 were included. Eighteen cases (47%) had a delayed diagnosis (median: 5 days). The main misdiagnosis was immune thrombocytopenia (67%). The mortality rate was 5% (1 death in each group). Neurological events (stroke/TIA, seizure, altered mental status) occurred in 67% vs 30% patients in group 1 and 2, respectively (p = 0.04). Two patients in group 1 exhibited neurological sequelae. The hospital length of stay was longer in group 1 (p = 0.02). At the first hospital evaluation, potential alternative causes of thrombocytopenia were more prevalent in group 1 (33% vs 5%, p = 0.04). Anemia was less frequent in group 1 (67% vs 95%, p = 0.04). All patients had undetectable haptoglobin levels. By contrast, 26% of schistocytes counts were <1%, mostly in group 1 (62% vs 11%, p = 0.01).
Diagnostic delay is highly prevalent in iTTP, with a significant impact on short-term neurological outcome. In patients with profound thrombocytopenia, the thorough search for signs of incipient organ dysfunction, systematic hemolysis workup, and proper interpretation of schistocytes count are the key elements of early diagnosis of TTP.
免疫介导的血栓性血小板减少性紫癜（iTTP）是一种罕见的危及生命的血栓性微血管病，需要紧急进行治疗性血浆置换（TPE）。然而，TPE 开始稍晚对后续患者预后的具体影响仍存在争议。
我们旨在研究 iTTP 中诊断延迟的频率、短期神经后果和决定因素。
我们进行了一项回顾性单中心研究，纳入了 2005 年至 2020 年间首次发生急性 iTTP 的患者（42 例），分为 2 组：延迟诊断（自首次就诊至开始 TPE 的时间>24 小时，组 1）和即刻诊断（≤24 小时，组 2）。
在评估的 42 例患者中，38 例纳入研究。18 例（47%）患者诊断延迟（中位数：5 天）。主要误诊为免疫性血小板减少症（67%）。死亡率为 5%（每组各 1 例死亡）。组 1 和 2 中分别有 67%和 30%的患者发生神经事件（中风/TIA、癫痫发作、意识状态改变）（p=0.04）。组 1 中有 2 例患者出现神经后遗症。组 1 的住院时间较长（p=0.02）。在首次就诊时，组 1 中潜在的血小板减少症其他病因更为常见（33% vs 5%，p=0.04）。组 1 中贫血发生率较低（67% vs 95%，p=0.04）。所有患者的结合珠蛋白水平均无法检测到。相比之下，组 1 中<1%的裂体细胞计数占 26%（62% vs 11%，p=0.01）。
iTTP 中诊断延迟非常常见，对短期神经预后有显著影响。在血小板严重减少的患者中，全面寻找早期器官功能障碍的迹象、系统进行溶血性检查以及正确解读裂体细胞计数是早期诊断 TTP 的关键要素。
