Development and Validation of a Between Primary PLA2R-Negative Membranous Nephropathy and Minimal Change Disease Confirmed by Renal Biopsy

Abstract Background: Membranous nephropathy (MN) and minimal change disease (MCD) are two common causes leading to nephrotic syndrome (NS). They have similar clinical feature but different treatment strategy and prognosis. M-type phospholipase A2 receptor (PLA2R) is considered as a specific marker of membranous nephropathy. However, its sensitivity is only about 70%. Therefore, there is a lack of effective and noninvasive tools to distinguish PLA2R-negative MN and MCD patients without renal biopsy. We aim to develop a discrimination model using noninvasive parameters for distinguishing the two diseases and support immediate treatment before result of renal biopsy.Methods: A total 949 patients who were pathologically diagnosed as idiopathic MN or primary MCD in the First Affiliated Hospital of Zhengzhou University from January 2017 to August 2019 were enrolled in this study, including 805 idiopathic MN (605 PLAR2-positive MN and 200 PLA2R-negative MN) and 144 primary MCD. Based on the basic information and laboratory examination of 200 PLA2R-negative MN and 144 MCD, we used a univariate and multivariate logistic regression to select the relevant variables and develop the discrimination model. ROC curve and calibration curve were used to evaluate the diagnostic ability and calibration ability of the model. The decision curve was used to calculate the net benefit. We also test the effectiveness of our model in all 949 patients.Results: A novel model that included age, albumin, urea, high density lipoprotein, urea and red blood cell count was established for PLA2R-negative MN and MCD. The discrimination model has excellent differential capability (an AUC of 0.889 in training group and an AUC of 0.920 in test group) and calibration capability. When testing in all 949 patients, our model also showed good discrimination ability for all idiopathic MN and MCD.Conclusion: We constructed a discrimination model with high diagnostic effectiveness for PLA2R-negative MN and MCD. The model could also be used for all idiopathic MN and MCD patients.