Division of Hematology, Department of Medicine, Johns Hopkins University School of Medicine, Ross Research 1032, 720 Rutland Avenue, Baltimore, MD 21205, USA.
Transfusion. 2010 Apr;50(4):868-74. doi: 10.1111/j.1537-2995.2009.02528.x. Epub 2009 Dec 10.
Plasma exchange, the standard treatment for thrombotic thrombocytopenic purpura (TTP), has significantly decreased disease mortality. However, TTP recurs in 20% to 50% of patients who survive the initial episode. We aimed to describe the clinical spectrum of TTP, to determine the valid endpoint for plasma exchange cessation, and to explore the risk factors for disease relapse.
Using the ICD-9 diagnosis code, we identified patients treated for TTP at the Johns Hopkins Hospital between 1992 and 2008. Complete demographic, clinical, laboratory, treatment, and outcome data were collected from the medical records.
A total of 72 patients were treated for 134 episodes of TTP at the Johns Hopkins Hospital during the study period. With standardized combined immunosuppression and plasma exchange treatment, the all-cause mortality rate was 4%. Lactate dehydrogenase (LDH) normalization lagged behind platelet (PLT) recovery by an average of 9 days and did not predict response. Relapse occurred in 36% of patients during a median follow-up of 30 months with most (76%) occurring in the first 24 months. African American ethnicity was associated with increased risk of relapse (odds ratio = 4.8, p = 0.03).
Excellent outcomes in patients with TTP are achievable with multimodality therapy. LDH normalization lags behind PLT recovery and might not be an informative endpoint for plasma exchange cessation. Prospective studies are warranted to confirm the influence of race on relapse and identify additional risk factors for adverse outcomes that could be targeted to improve therapeutic outcomes for patients with TTP.
血浆置换是血栓性血小板减少性紫癜（TTP）的标准治疗方法，它显著降低了疾病的死亡率。然而，在初始发作中幸存下来的患者中有 20%至 50%会复发 TTP。我们旨在描述 TTP 的临床谱，确定血浆置换停止的有效终点，并探讨疾病复发的危险因素。
使用 ICD-9 诊断代码，我们确定了 1992 年至 2008 年期间在约翰霍普金斯医院接受 TTP 治疗的患者。从病历中收集了完整的人口统计学、临床、实验室、治疗和结局数据。
在研究期间，共有 72 名患者在约翰霍普金斯医院接受了 134 次 TTP 治疗。采用标准化联合免疫抑制和血浆置换治疗，总死亡率为 4%。乳酸脱氢酶（LDH）正常化滞后于血小板（PLT）恢复，平均滞后 9 天，且不能预测反应。在中位随访 30 个月期间，36%的患者复发，其中大多数（76%）发生在第 24 个月内。非裔美国人的种族与复发风险增加相关（优势比=4.8，p=0.03）。
多模式治疗可使 TTP 患者获得良好的结局。LDH 正常化滞后于 PLT 恢复，可能不是血浆置换停止的有用终点。需要前瞻性研究来证实种族对复发的影响，并确定其他不良预后的危险因素，以便针对 TTP 患者的治疗结果进行改进。
