Csernok E, Ahlquist D, Ullrich S, Gross W L
Department of Rheumatology, University of Lübeck and Rheumaklinik Bad Bramstedt, Germany.
Rheumatology (Oxford). 2002 Nov;41(11):1313-7. doi: 10.1093/rheumatology/41.11.1313.
To evaluate the performance of 11 commercial enzyme-linked immunosorbent assay (ELISA) kits for the detection of antineutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) and myeloperoxidase (MPO) in patients with Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA).
Serum samples were taken from 92 patients with a histological and clinical diagnosis of WG (n=50) or MPA (n=42) and from 30 disease controls (systemic lupus erythematosus, n=15; rheumatoid arthritis, n=15) and 30 healthy controls. Each of the sera was tested for the presence of ANCA directed against PR3 and MPO using 11 commercially available direct ELISA kits, our in-house PR3- and MPO-ANCA capture ELISAs, and the indirect immunofluorescence technique (IFT).
In tests for WG using PR3-ANCA, the commercial direct ELISA kits differed widely in their sensitivity (from 22 to 70%) and negative predictive value (NPV) (from 43 to 70%), but only moderately in their specificity (from 93 to 100%) and positive predictive value (PPV) (from 93 to 100%). The highest sensitivity (74%) and specificity (100%) for PR3-ANCA were obtained with the in-house capture ELISA. Similar differences and trends were noted for MPO-ANCA assays. Diagnostic sensitivity was more than 60% for four and at least 50% for six of the 11 ELISA kits. The PPV varied from 84 to 100% and the NPV from 58 to 70%. In tests for MPA, the MPO-ANCA ELISA kit designated F and the in-house capture ELISA were best (both had sensitivity 62% and specificity 100%). For both WG and MPA, maximum sensitivity for ANCA was obtained with IFT (80 and 70% respectively).
Determination of PR3-ANCA and MPO-ANCA with the commercial direct ELISA kits achieved poor sensitivity for both WG and MPA. The in-house PR3 and MPO-ANCA capture ELISAs performed better than the commercial ELISAs, combining higher specificity with similar sensitivity. IFT remains the best method for ANCA detection in both diseases.
评估11种商用酶联免疫吸附测定（ELISA）试剂盒检测韦格纳肉芽肿（WG）和显微镜下多血管炎（MPA）患者中抗蛋白酶3（PR3）和髓过氧化物酶（MPO）的抗中性粒细胞胞浆抗体（ANCA）的性能。
采集92例经组织学和临床诊断为WG（n = 50）或MPA（n = 42）的患者、30例疾病对照（系统性红斑狼疮，n = 15；类风湿关节炎，n = 15）以及30例健康对照的血清样本。使用11种市售直接ELISA试剂盒、我们内部的PR3和MPO - ANCA捕获ELISA以及间接免疫荧光技术（IFT）检测每份血清中抗PR3和MPO的ANCA。
在使用PR3 - ANCA检测WG时，商用直接ELISA试剂盒在敏感性（从22%到70%）和阴性预测值（NPV）（从43%到70%）方面差异很大，但在特异性（从93%到100%）和阳性预测值（PPV）（从93%到100%）方面差异适中。内部捕获ELISA对PR3 - ANCA的敏感性最高（74%），特异性最高（100%）。MPO - ANCA检测也有类似的差异和趋势。11种ELISA试剂盒中有4种的诊断敏感性超过60%，6种至少为50%。PPV从84%到100%不等，NPV从58%到70%不等。在检测MPA时，指定为F的MPO - ANCA ELISA试剂盒和内部捕获ELISA表现最佳（敏感性均为62%，特异性均为100%）。对于WG和MPA，IFT检测ANCA的敏感性最高（分别为80%和70%）。
使用商用直接ELISA试剂盒检测PR3 - ANCA和MPO - ANCA对WG和MPA的敏感性均较差。内部PR3和MPO - ANCA捕获ELISA的性能优于商用ELISA，具有更高的特异性和相似的敏感性。IFT仍然是这两种疾病中检测ANCA的最佳方法。
