PLA2R、THSD7A及IgG4在特发性膜性肾病中的临床应用

Clinical application evaluation of PLA2R,THSD7A,and IgG4 in idiopathic membranous nephropathy

目的研究并探讨磷脂酶A2受体(Phospholipase A2 receptor,PLA2R)、1型血小板反应蛋白7A域(Thrombospondin type-1 domain-containing 7A,THSD7A)及IgG4在特发性膜性肾病(Idiopathic membranous nephropathy,IMN)中的临床应用评价。方法选取2021年6月至2023年8月根据纳排标准行经皮肾穿刺活检术患者共计134例,按照肾脏穿刺活检病理诊断结果将患者分为IMN组和非IMN组,对比两组患者的临床资料、肾组织中PLA2R、THSD7A、免疫球蛋白及补体表达情况以及IMN组PLA2R抗体阳性与阴性之间的差异,分析其相关性并绘制ROC曲线,探讨其诊断价值;结果IMN患者中在年龄、血清PLA2R滴度、肾组织PLA2R阳性率、肾组织免疫球蛋白IgG1、IgG4及C3荧光强度均高于非IMN组;IMN患者血清PLA2R阳性组的24hUP(24-hour uriary protein)明显高于阴性组,血浆白蛋白低于阴性组;线性回归分析,血清PLA2R-Ab与发病年龄及24hUP的变化量呈现正相关(R=0.318,P=0.039、R=0.511,P=0.014);在IMN诊断中,血清PLA2R抗体、血清THSD7A抗体、肾组织PLA2R、肾组织THSD7A、肾组织IgG4特异度分别是88.17%、63.49%、79.81%、63.07%、74.18%;敏感性最高为肾组织IgG4(98.03%)且曲线下面积最大;THSD7A因阳性率较低,组间比较差异均未见统计学意义。结论血清PLA2R抗体、肾组织PLA2R、肾组织THSD7A、肾组织IgG4对IMN具有诊断及鉴别诊断价值,PLA2R抗体滴度较高的患者相对年龄较大,可能更易出现大量蛋白尿或和低蛋白血症,而THSD7A因阳性率较低,暂未见明确的相关性,需要后续开展更大的样本量进行研究。

Objective To study and discuss the evaluation of clinical application of Phospholipase A2 receptor(PLA2R),thrombospondin type-1 domain-containing 7A(THSD7A)and IgG4 in idiopathic membranous nephropathy(IMN).Methods From June,2021 to August,2023,134 patients with glomerular disease were selected from Bazhou People's Hospital in Xinjiang as the research object.According to the pathological diagnosis results of renal biopsy,the patients were divided into Idiopathic membranous nephropathy group and non-IMN group,and the expressions of serum PLA2R,renal tissue PLA2R,THSD7A and IgG4 were detected.The general data,serum PLA2R,serum THSD7A,,renal tissue PLA2R,renal tissue THSD7A,immunoglobulin and complement expression of the two groups were compared,Analyze the difference between positive and negative PLA2R antibodies in the IMN group,analyze their correlation,and draw ROC curves to explore their diagnostic value。Results In IMN patients,the age,serum PLA2R titer,positive rate of PLA2R in renal tissue,and fluorescence intensity of immunoglobulins IgG1,IgG4,and C3 in renal tissue were higher than those in non IMN groups;The 24-hour UP of the serum PLA2R positive group in IMN patients was significantly higher than that of the negative group,and the plasma albumin was lower than that of the negative group;Linear regression analysis showed a positive correlation between serum PLA2R Ab and age of onset and changes in 24-hour UP(R=0.318,P=0.039,R=0.511,P=0.014);In the diagnosis of IMN,the specificity of serum PLA2R antibody,serum THSD7A antibody,renal tissue PLA2R,renal tissue THSD7A,and renal tissue IgG4 were 88.17%,63.49%,79.81%,63.07%,and 74.18%,respectively;The highest sensitivity was IgG4 in renal tissue(98.03%)and the area under the curve was the largest;Due to the low positive rate of THSD7A,there was no statistically significant difference between groups.Conclusion Serum PLA2R Ab,renal tissue PLA2R,renal tissue THSD7A,and renal tissue IgG4 have diagnostic and differential diagnostic value for IMN.Patients with higher PLA2R antibody titers are relatively older and may be more prone to developing large amounts of proteinuria or hypoproteinemia.However,THSD7A,due to its lower positive rate,needs to be studied with a larger sample size in the future.