The role of serum levels of anti-phospholipase A2 receptor antibodies in the diagnosis of primary membranous nephropathy.

Abstract

Primary membranous nephropathy (PMN) is one of the most common causes of nephrotic syndrome in adults. The disease process is probably initiated by the binding of circulating autoantibodies to target podocyte antigens. In 2009, Beck et al. found that phospholipase A2 receptor (PLA2R1) was expressed on human podocytes in patients with PMN. Recent evidence suggests that PLA2R1 autoantibodies play an important role in the diagnosis of PMN. The aim of the present study was to compare the serum levels of anti-PLA2R1 in patients with PMN, second MN (SMN), other nephropathies (ON), and healthy controls (HC). The study included 52 patients with PMN, 12 patients with SMN, 49 patients with ON, and 50 healthy controls. The serum concentration of anti-PLA2R1 was determined with ELISA kit (Anti-PLA2R ELISA, IgG, EUROIMMUN, Lübeck, Germany) using MR-96A microplate Reader (MINDRAY). Statistical analysis was performed with SPSS v.22.0. There was significant difference in the serum anti-PLA2R1 concentrations between patient groups and HC (p<0.0001). Compared to HC, the median anti-PLA2R1 level in the PMN group was significantly higher (4.8 RU/ml vs. 34.9 RU/ml, p=0.001), in the ON group it was lower (2.1 RU/ml, p=0.002) and did not differ in patients with SMN (2.9 RU/ml, p=0.193). The anti-PLA2R1 serum levels were significantly higher in the PMN group than in the SMN (p=0.015) and ON (p<0.001) groups. Our results showed that anti-PLA2R1 is significantly increased in patients with PMN. We can conclude that the anti-PLA2R1 serum concentration may be used as a beneficial biomarker for distinguishing PMN from other membranous nephropathies.