Center for Rheumatic Diseases, Neuss, Germany.
Clin Chim Acta. 2012 Dec 24;414:266-72. doi: 10.1016/j.cca.2012.09.015. Epub 2012 Sep 25.
We compared 2 anti-citrullinated protein antibody (ACPA) assays using a routine patient cohort.
Two-hundred ninety-five sera were collected from patients for whom ACPA was ordered and tested for ACPA by QUANTA Lite® CCP 3 (INOVA Diagnostics, Inc., San Diego) and EliA® CCP (CCP, Phadia, Germany). Rheumatoid factor (RF) was determined using Quantex RF(II) (Biokit, Spain).
Acceptable qualitative (96.6%, kappa=0.93) and quantitative agreements (Spearman rho=0.77; p<0.0001) were observed between the two ACPA assays. Nine samples were CCP3+/CCP2- and one sample was CCP2+/CCP3-. Of the 9 CCP3+/CCP2- patients, 6 (66.7%) had RA, one patient had ankylosing spondylitis, one osteoarthritis and one psoriatic arthritis. The CCP3-/CCP2+ patient had juvenile RA. At the manufacturer's cut-offs, the sensitivities and specificities were 77.3%/98.1% (CCP2), 81.6%/96.8% (CCP3) and 65.2%/89.6% (RF), respectively. At 98.7% specificity level, the sensitivities in the total cohort were 59.6% (CCP2) and 69.5% (CCP3) while the sensitivities in the RF-negative group were 49.0% (CCP2) and 57.1% (CCP3). In the RF-negative group, sensitivities for patients with a disease duration of ≤ 5years were 38.7% (CCP2) and 51.6% (CCP3).
Discrimination between RA and non-RA patients was better using CCP3, most pronounced in RF-negative RA.
我们比较了两种抗瓜氨酸蛋白抗体（ACPA）检测方法，使用的是常规患者队列。
从需要检测 ACPA 的患者中收集了 295 份血清，并使用 QUANTA Lite® CCP 3（INOVA Diagnostics，Inc.，圣地亚哥）和 EliA® CCP（CCP，Phadia，德国）进行检测。使用 Quantex RF（II）（Biokit，西班牙）检测类风湿因子（RF）。
两种 ACPA 检测方法之间观察到了可接受的定性（96.6%，kappa=0.93）和定量一致性（Spearman rho=0.77；p<0.0001）。有 9 份样本为 CCP3+/CCP2-，有 1 份样本为 CCP2+/CCP3+。在 9 份 CCP3+/CCP2-的患者中，有 6 例（66.7%）为 RA，1 例为强直性脊柱炎，1 例为骨关节炎，1 例为银屑病关节炎。CP3-/CCP2+的患者患有幼年型 RA。在制造商的截断值下，灵敏度和特异性分别为 77.3%/98.1%（CCP2）、81.6%/96.8%（CCP3）和 65.2%/89.6%（RF）。在特异性为 98.7%的水平下，总队列的灵敏度分别为 59.6%（CCP2）和 69.5%（CCP3），而 RF 阴性组的灵敏度分别为 49.0%（CCP2）和 57.1%（CCP3）。在 RF 阴性组中，病程≤5 年的患者的灵敏度分别为 38.7%（CCP2）和 51.6%（CCP3）。
使用 CCP3 区分 RA 和非 RA 患者的效果更好，在 RF 阴性的 RA 患者中最为明显。
