Nguyen Loan, Li Xiaoning, Duvall Deanna, Terrell Deirdra R, Vesely Sara K, George James N
Department of Biostatistics and Epidemiology, College of Public Health, The University of Oklahoma Health Science Center, Oklahoma City, OK 73190, USA.
Transfusion. 2008 Feb;48(2):349-57. doi: 10.1111/j.1537-2995.2007.01530.x. Epub 2007 Nov 19.
Twice-daily plasma exchange has been used for patients with thrombotic thrombocytopenic purpura (TTP) who are unresponsive to treatment with daily plasma exchange for many years but with no clear evidence of effectiveness.
The 18 years' experience of The Oklahoma TTP-HUS (hemolytic-uremic syndrome) Registry, 1989 through 2006, with twice-daily plasma exchange for 31 episodes of TTP in 28 patients is reported. A definite response to twice-daily plasma exchange was defined a priori as a platelet (PLT) count increase after twice-daily plasma exchange on two separate occasions during the treatment of a single episode of TTP, with no change of other treatments. A possible response was defined as a PLT count increase after initiation of twice-daily plasma exchange only once with or without change of other treatments.
A definite response to twice-daily plasma exchange occurred in 3 episodes (three patients), 27 episodes had a possible response, and 1 episode had no response. The three patients with a definite response had ADAMTS13 activities of 5, 6, and 12 percent and all had an inhibitor; the patient with no response was subsequently determined to have Rocky Mountain spotted fever.
Twice-daily plasma exchange was typically considered in acutely ill patients who had initially responded but then severe thrombocytopenia recurred, often with new neurologic abnormalities, while continuing daily plasma exchange. In three patients, twice-daily plasma exchange appeared to be beneficial. In most patients, a benefit of twice-daily plasma exchange could not be clearly documented because other treatments were initiated or intensified.
多年来，对于对每日血浆置换治疗无反应的血栓性血小板减少性紫癜（TTP）患者，一直采用每日两次的血浆置换，但尚无明确的有效性证据。
报告了俄克拉荷马州TTP-溶血尿毒综合征（HUS）登记处1989年至2006年18年的经验，其中28例患者的31次TTP发作采用了每日两次的血浆置换。对每日两次血浆置换的明确反应预先定义为在单次TTP发作治疗期间，在两个不同时间进行每日两次血浆置换后血小板（PLT）计数增加，且其他治疗无变化。可能的反应定义为仅在开始每日两次血浆置换后血小板计数增加一次，无论其他治疗是否改变。
3次发作（3例患者）对每日两次血浆置换有明确反应，27次发作有可能反应，1次发作无反应。3例有明确反应的患者ADAMTS13活性分别为5%、6%和12%，且均有抑制剂；无反应的患者随后被确定患有落基山斑疹热。
对于最初有反应但随后严重血小板减少复发（常伴有新的神经异常）的急性病患者，在继续每日血浆置换的同时，通常会考虑每日两次血浆置换。在3例患者中，每日两次血浆置换似乎有益。在大多数患者中，由于开始或加强了其他治疗，无法明确记录每日两次血浆置换的益处。
