Escalante A, Brey R L, Mitchell B D, Dreiner U
Section of Rheumatology, University of Texas Health Science Center at San Antonio 78284-7874, USA.
Am J Med. 1995 Jun;98(6):559-65. doi: 10.1016/s0002-9343(99)80014-x.
To measure the accuracy of anticardiolipin antibodies (aCL) in identifying a history of thrombosis among patients with systemic lupus erythematosus (SLE) or the primary antiphospholipid syndrome (PAPS).
Patients with SLE or PAPS who attended our rheumatology clinic between April 1992 and March 1994 were included in a retrospective analysis of the relationship between thrombotic events and aCL. All aCL measurements were performed in the same laboratory by enzyme-linked immunosorbent assay, blinded as to the presence or absence of thrombosis. The diagnostic accuracy of IgG, IgM, and IgA aCL was quantified by means of the receiver operating characteristic area under the curve (ROC AUC) for each isotype. Stratum-specific likelihood ratios and their 95% confidence intervals were calculated to define strata with optimal discriminant power.
During the period of study, aCL was measured in 117 patients (113 SLE and 4 PAPS), of whom 24 (20.5%) had experienced thrombotic events. The ROC AUC +/- the standard error for IgG aCL was 0.81 +/- 0.05, signifying an 81% accuracy in the identification of a history of thrombosis. In contrast, the accuracy of the IgM and IgA aCL was significantly lower (0.60 +/- 0.08 and 0.54 +/- 0.07, respectively, P < 0.05). Using stratum-specific likelihood ratios, we defined three strata in the IgG aCL scale that discriminate between patients with low, indeterminate, and high probabilities of thrombosis. For IgG aCL levels below 21.4 IgG phospholipid (GPL) U/mL, the posttest probability of thrombosis was 0.07, whereas for IgG aCL levels > or = 65.1 GPL U/mL, the posttest probability of thrombosis was 0.75. For IgG aCL values between 21.4 and 65.0 GPL U/mL, the probability of thrombosis was 0.20, equivalent to the entire cohort.
The IgG aCL determinations perform well in the identification of thrombosis in SLE or PAPS, while the IgM and IgA aCL have poor diagnostic accuracy. These findings may have implications for management of these patients.
测定抗心磷脂抗体（aCL）在识别系统性红斑狼疮（SLE）或原发性抗磷脂综合征（PAPS）患者血栓形成病史方面的准确性。
1992年4月至1994年3月期间在我们风湿科门诊就诊的SLE或PAPS患者被纳入血栓形成事件与aCL之间关系的回顾性分析。所有aCL检测均在同一实验室采用酶联免疫吸附测定法进行，检测时对是否存在血栓形成情况进行盲法处理。通过计算每种亚型的曲线下面积（ROC AUC）来量化IgG、IgM和IgA aCL的诊断准确性。计算特定分层似然比及其95%置信区间，以确定具有最佳判别能力的分层。
在研究期间，对117例患者（113例SLE和4例PAPS）进行了aCL检测，其中24例（20.5%）有血栓形成事件。IgG aCL的ROC AUC±标准误为0.81±0.05，表明识别血栓形成病史的准确率为81%。相比之下，IgM和IgA aCL的准确性显著较低（分别为0.60±0.08和0.54±0.07，P<0.05）。利用特定分层似然比，我们在IgG aCL量表中定义了三个分层，用于区分血栓形成概率低、不确定和高的患者。对于IgG aCL水平低于21.4 IgG磷脂（GPL）U/mL的患者，血栓形成的检测后概率为0.07，而对于IgG aCL水平≥65.1 GPL U/mL的患者，血栓形成的检测后概率为0.75。对于IgG aCL值在21.4至65.0 GPL U/mL之间的患者，血栓形成概率为0.20，与整个队列的概率相当。
IgG aCL测定在识别SLE或PAPS患者的血栓形成方面表现良好，而IgM和IgA aCL的诊断准确性较差。这些发现可能对这些患者的管理具有启示意义。
