ELISA检测血清抗磷脂酶A_2受体抗体在膜性肾病中的应用探讨

Study on application of serum anti-phospholipase A_2 receptor antibodies detection by ELISA in membranous nephropathy

目的探讨酶联免疫吸附试验(ELISA)检测血清抗磷脂酶A2受体抗体(抗PLA2R抗体)滴度在膜性肾病中的应用价值为疾病诊断及病情判断提供更特异的血清学指标。方法选取该院肾内科就诊行肾组织活检并确诊的膜性肾病患者34例,该院住院自身免疫性疾病及肾病综合征、肾功能不全患者32例,健康体检者12例,收集血清检测抗PLA2R抗体并结合血清总蛋白(TP)、清蛋白(ALB)、IgG、IgA、IgM、C3、C4指标,分析其对膜性肾病的诊断性能。结果抗PLA2R抗体滴度在膜性肾病组、疾病对照组、健康对照组中位数依次为22.1、2.0、2.0RU/mL,膜性肾病组与其他两组间比较差异有统计学意义(P<0.05)。抗PLA2R抗体在膜性肾病组阳性17例(阳性率50%),阴性17例,疾病对照组及健康对照组均为阴性,其特异度与阳性预测值为100%。膜性肾病组TP、ALB、IgG与疾病对照组、健康对照组比较差异有统计学意义(P<0.05);抗PLA2R抗体与血清TP、ALB、IgG、IgA、IgM、C3、C4的相关系数依次为-0.382、-0.344、-0.502、-0.295、0.062、0.005、0.241,与TP、ALB、IgG、IgA呈负相关(P<0.01),与C4呈正相关(P<0.05),与IgM、C3无相关性(P>0.05)。结论抗PLA2R抗体在膜性肾病诊断中具有较高的特异性,可作为无法行肾活检患者的必要和特异性血清学检测指标,定量检测有助于病情判断。

Objective To explore the titre of serum anti-phospholipase A2 receptor antibodies（anti-PLA2 R antibodies）detected by the enzyme-linked immunosorbent assay（ELISA）to provide a more specific serological index for clinical diagnosis and disease judgment of membranous nephropathy（MN）.Methods Thirty-four cases of MN confirmed by kidney biopsy,32 inpatients with autoimmune diseases,nephrotic syndrome and renal insufficiency in the nephrology department of our hospital and 12 persons undergoing physical examination were selected.The serum was collected for detecting anti-PLA2 R antibodies level.Then its diagnostic performance for diagnosing MM was analyzed by combining with serum TP,ALB,IgG,IgA,IgM,C3 and C4indicators.ResultsThe medians of anti-PLA2 R antibodies titres in the MN group,disease control group and healthy control group were 22.1,2.0,2.0RU/mL respectively,which had statistical difference between the MN group and other two groups（P〈0.05）.Seventeen cases of anti-PLA2 R antibodies positive were in the MN group（positive rate 50%）and 17 cases were negative,the disease control group and healthy control group all were negative.Its specificity and positive predictive value were 100%,TP,ALB and IgG had statistical difference between the MN group with the disease control group and healthy control group（P〈0.05）;the relative coefficients of anti-PLA2 R antibodies with TP,ALB and IgG,IgA,IgM,C3 and C4were in turn-0.382,-0.344,-0.502,-0.295,0.062,0.005 and 0.241 respectively,anti-PLA2 R antibodies were negatively correlated with TP,ALB,IgG and IgA（P〈0.01）,positively correlated with C4（P〈0.05）and had no relation with IgM and C3（P〉0.05）.Conclusion Anti-PLA2 R antibodies have higher specificity for the diagnosis of MN and can serve as the necessary and specific serologic detection indicator in the patients unable to conduct renal biopsy.Quantitative detection helps to condition judgment.