Relationship between the status of phospholipase A2 receptor and prognosis of idiopathic membranous nephropathy

Aim Serum levels of phospholipase A2 receptor antibody (PLA2R; SAb) and glomerular deposits of PLA2R antigen (GAg) have been detected in patients with idiopathic membranous nephropathy (IMN). However, the correlation between these immunologic factors and their associations with the status and prognosis of IMN remain uncertain. Methods Fifty-one patients with biopsy-proven IMN diagnosed between March of 2015 and December of 2016 were enrolled in this study. All the patients were followed until March of 2017.We used enzyme-linked immunosorbent assay and immunofluorescence to measure the SAb and GAg, respectively. Results The positive rate of GAg was significantly higher than SAb in patients with IMN (88.24 vs 66.77%, P = 0.017). Compared with SAb- patients, SAb+ patients had a higher baseline proteinuria (6.21 vs 3.40 g/24 h), lower serum albumin (22.49 +/- 6.59 vs 29.09 +/- 7.40 g/L) and poorer renal function (88.96 +/- 21.17 vs 107.25 +/- 20.04 mL/min per 1.73 m(2)), as well as a higher renal IgG4 level (P < 0.05). A comparison of SAb+/GAg+ and SAb-/GAg+ tissues yielded similar results (P < 0.01). Regarding prognosis, SAb- patients had a higher rate of complete remission after immunosuppressive treatment than SAb+ patients (P = 0.042). Conclusion The disease status and prognosis correlated more closely with the SAb than with the GAg in our cohort of patients with IMN. Furthermore, SAb+ patients had more severe clinical symptoms and a worse prognosis, which was probably associated with increased IgG4 deposition.