我国人群血清PLA2R 抗体诊断IMN 的 最佳截断值探讨

Discussion about optimal cut-off value of PLA2R antibody for Chinese cohort

摘要:

目的 血清磷脂酶A2 受体（PLA2R）抗体对特发性膜性肾病（IMN）的诊断价值已经得到广泛 认同，但国外血清PLA2R 抗体对IMN 的诊断截断值不一定适合我国，因此笔者拟探讨我国血清PLA2R 抗体 诊断IMN 的最佳截断值。方法 选取2016 年1 月—2018 年1 月于江西省赣州市人民医院肾内科住院行肾穿 刺活检的患者，采用酶联免疫吸附法检测血清PLA2R 抗体，其诊断价值行ROC 曲线分析，探讨血清PLA2R 抗体诊断IMN 的敏感性和特异性，取约登指数最大时的检测值作为阳性截断值。结果 血清PLA2R 抗体诊 断IMN 的曲线下面积（AUC）为0.924（95%CI ：0.844，1.000），与机会一致性诊断AUC=0.5 比较，差异有 统计学意义（P <0.05）。当截断值取2.92 Ru/ml 时，敏感性为0.818（95%CI ：0.750，0.876），特异性为0.935 （95%CI ：0.888，0.966），阳性预测值为0.900，阴性预测值为0.879，约登指数为0.753。结论 目前被广泛采 用的血清PLA2R 抗体对诊断IMN 的临界值仍需要通过多中心大样本量的研究来进一步探讨和修正。

Abstract:

Objective To assess the appropriate cut-off value of serum anti-phospholipase A2 receptor (PLA2R) antibody for diagnosis of idiopathic membranous nephropathy (IMN) in Chinese cohort. Methods The patients being hospitalized for renal biopsy in Department of Nephrology in Ganzhou People’s Hospital from January 2016 to January 2018 were selected in this study. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum anti-PLA2R antibody. ROC curve was used to assess the diagnostic value of serum anti-PLA2R antibody, and its sensitivity and specificity for the diagnosis of IMN were explored, the value at the maximal Youden index was taken the optimal cut-off value. Results The area under the ROC curve (AUC) of serum anti-PLA2R antibody for diagnosis of IMN was 0.924 (95% CI: 0.844, 1.000), compared with the opportunistic diagnostic AUC of 0.5, the difference was statistically significant (P < 0.05). When 2.92 Ru/ml was taken as the cut-off value, the sensitivity was 0.818 (95% CI: 0.750, 0.876), the specificity was 0.935 (95% CI: 0.888, 0.966), the positive predictive value was 0.900, the negative predictive value was 0.879, and the Youden index was 0.753. Conclusions The cut-off value of serum anti-PLA2R antibody for the diagnosis of IMN should be further explored and amended by multi-center and larger sample size study.