The Significance Of PLA2R And Its Antibody In The Diagnosis And Treatment Of Membranous Nephropathy

Objective:Idiopathic membranous nephropathy(IMN)is one of the glomerulopathy,with the nephrotic syndrome as main clinical manifestation,the damaged glomerular basement membrane as the main pathological features.In recent years,circulating autoantibody of M-type phospholipase A2 receptor has been discovered in the serum of approximately 74% IMN patients,and autoantibody was also found in serum.However,to the serum anti-PLA2R and renal PLA2R,little was understood about how each of them influences the feature of IMN.The purpose of this research is to analyze the correlation between the expressions of serum anti-PLA2R and renal PLA2R,and assess the relationship of serum anti-PLA2R and renal PLA2R for the diagnosis,prognosis and disease activity for IMN.Method:1.36 IMN cases were involved proven by renal biopsy from March 2016 to December 2016 in the Affiliated Hospital of Qingdao University.14 MCD,LN-V and Ig A non-IMN cases were involved as the match group.The difference of various indexes between IMN and non-IMN cases were analyzed.2.The Immunohistochemistry(IHC)was used to measure the expression of renal PLA2R of two groups.The ELISA was used to measure titer of serum anti-PLA2R.The positive rate of different groups was calculated and the dependency of two index of IMN patients was analyzed.3.The SPSS was used to draw the ROC of patients,and the accuracy of PLA2R and antibody for the IMN diagnose was analyzed.4.The relationship between the expression of PLA2R and antibody and the degree of impaired kidney was analyzed in IMN patients.5.We divided the patients who the PLA2R is positive into positive and negative antibody groups.The difference of the degree of impaired kidney of two groups was measured.6.The relationship between antibody titer and level of disease activity was analyzed in IMN patients.7.The clinical follow-up survey of 33 patients were collected,we analyzed the relationship PLA2R,antibody and prognosis.Results:1.Between IMN group and match group,there were no statistical significance(p>0.05)among age,gender,blood pressure,24 h urine protein quantitation,serum albumin and serum creatinine.2.The sensitivity of PLA2R of IMN was 75.00%,the specificity was 85.71%;the sensitivity of serum PLA2R antibody of IMN was 63.89%,the specificity was 92.86%;the sensitivity of PLA2R in renal tissue and serum PLA2R antibody was 75.00%,the specificity was 78.57%.3.The AUCROC of antibody PLA2R was 0.784,and the AUCROC of renal PLA2R was 0.875.4.There were no statistical significance(p>0.05)between the serum creatinine of positive and negative antibody PLA2R of IMN.The 24h urine protein quantitation of positive and negative PLA2R antibody patients were 5.56±2.80 g/24 h and 3.79±1.04 g/24h(p=0.013),and the serum albumin were 21.23±4.79 g/L and 24.41±3.83 g/L(p=0.032).There were significant variation of the two index which were measured by the independent-samples T test.There were no statistical significance(p>0.05)among 24 h urine protein quantitation and serum albumin between positive and negative renal PLA2R of IMN.5.For the IMN positive PLA2R,there were no significant variation among the creatinine,albumin and 24 h urine protein quantitation between the positive and negative antibody.6.For the IMN patients the antibody titer was positively correlated with 24-hour urinary protein quantitation(r=0.874,p<0.001),was negatively correlated with serum albumin(r=-0.779,p<0.001).7.After the three month immunosuppressive therapy,through the calculation by the Fisher,there were no statistical significance(p>0.05)of remission rate between the positive(41.7%)and negative(66.7%)renal PLA2R.The remission state of negative antibody PLA2R(75%)were better than the positive antibody PLA2R(33.3%).Conclusion:The expression of renal PLA2R and antibody PLA2R are not closed match in IMN patients.The renal-PLA2R-positive patients were found negative in antibody PLA2R expression.The renal and antibody PLA2R have good sensitive and specificity to diagnose of the IMN patients,furthermore,it possess value of disease diagnosis.The expression of renal PLA2R and antibody PLA2R are associated with hypoalbuminemia,which are independent of the antigen,may reflect the severity of the disease.In addition,antibody titer has the linear relationship with urine protein quantitation and blood albumin level.The treatment of renal and antibody PLA2R negative patients are better than the positive patients.