Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Augustenburger Platz 01, 13555 Berlin, Germany.
Arthritis Res Ther. 2011 Jul 21;13(4):R118. doi: 10.1186/ar3421.
Diagnosis of antiphospholipid syndrome (APS) still remains a laboratory challenge due to the great diversity of antiphospholipid antibodies (aPL) and their significance regarding APS-diagnostic criteria.
A multi-line dot assay (MLDA) employing phosphatidylserine (PS), phosphatidylinositol (PI), cardiolipin (CL), and beta2-glycoprotein I (β2 GPI) was used to detect aPL, immunoglobulin G (IgG) and immunoglobulin M (IgM) in 85 APS patients, 65 disease controls, and 79 blood donors. For comparison, anti-CL and anti-β2 GPI IgG and IgM were detected by enzyme-linked immunosorbent assay (ELISA).
The level of agreement of both methods was good for anti-CL IgG, moderate for anti-CL IgM, very good for anti-β2 GPI IgG, and moderate for anti-β2 GPI IgM (kappa = 0.641, 0.507, 0.803 and 0.506, respectively). The frequency of observed discrepancies for anti-CL IgG (1.75%), anti-CL IgM (3.93%), anti-β2 GPI IgG (1.75%), and anti-β2 GPI IgM (0.87%) was low (McNemar test, P < 0.05, not-significant, respectively). Sensitivity, specificity, positive (+LR) and negative (-LR) likelihood ratios for at least one positive aPL antibody assessed by ELISA were 58.8%, 95.8%, 14.1, and 0.4, respectively, and for at least three positive aPl IgM and/or one positive aPL IgG by MLDA were 67.1%, 96.5%, 19.3, and 0.3, respectively. The frequency of IgM to PI, PS and CL, and combination of three or more aPL IgM detected by MLDA was significantly higher in APS patients with cerebral transient ischemia (P < 0.05, respectively).
The novel MLDA is a readily available, single-step, sensitive diagnostic tool for the multiplex detection of aPL antibodies in APS and a potential alternative for single aPL antibody testing by ELISA.
由于抗磷脂抗体（aPL）种类繁多，且其与抗磷脂综合征（APS）诊断标准的相关性各不相同，因此诊断抗磷脂综合征仍然是实验室面临的一项挑战。
采用多线点印迹法（MLDA）检测 85 例 APS 患者、65 例疾病对照组和 79 名献血者的抗磷脂酰丝氨酸（PS）、抗磷脂酰肌醇（PI）、抗心磷脂（CL）和抗β2-糖蛋白 I（β2 GPI）抗体 IgG 和 IgM。为了进行比较，还采用酶联免疫吸附试验（ELISA）检测抗 CL 和抗β2 GPI IgG 和 IgM。
两种方法检测抗 CL IgG 的一致性较好，检测抗 CL IgM 的一致性为中等，检测抗β2 GPI IgG 和 IgM 的一致性非常好（kappa 值分别为 0.641、0.507、0.803 和 0.506）。观察到抗 CL IgG（1.75%）、抗 CL IgM（3.93%）、抗β2 GPI IgG（1.75%）和抗β2 GPI IgM（0.87%）的差异频率较低（McNemar 检验，P<0.05，不显著）。至少一种阳性 aPL 抗体（ELISA 检测）的敏感性、特异性、阳性（+LR）和阴性（-LR）似然比分别为 58.8%、95.8%、14.1 和 0.4，至少三种阳性 aPL IgM 和/或一种阳性 aPL IgG（MLDA 检测）的敏感性、特异性、阳性（+LR）和阴性（-LR）似然比分别为 67.1%、96.5%、19.3 和 0.3。MLDA 检测到的抗 PI、PS 和 CL 的 IgM 以及三种或更多 aPL IgM 的组合在伴有短暂性脑缺血的 APS 患者中频率显著升高（P<0.05，分别）。
新型 MLDA 是一种易于获得的、一步法、敏感的诊断工具，可用于 APS 中 aPL 抗体的多重检测，是 ELISA 检测单一 aPL 抗体的潜在替代方法。
