Anti-phospholipase A2 receptor antibody as a prognostic marker in patients with primary membranous nephropathy

Abstract

Background: Phospholipase A2 receptor (PLA2R) has been identified as a major autoantigen in primary membranous nephropathy (MN). We evaluated the association between anti-PLA2R antibodies and clinical outcome in Korean patients with primary MN.

Methods: A total of 66 patients with biopsy-proven MN were included. Serum level of anti-PLA2R antibodies was measured by enzyme-linked immunosorbent assay. Biochemical parameters were estimated initially and at follow-up.

Results: Anti-PLA2R antibodies were detected in 52.1% and 27.8% of patients with primary and secondary MN, respectively. Forty-eight patients with primary MN were grouped based on presence or absence of anti-PLA2R antibodies. Proteinuria was more severe in anti-PLA2R-positive patients than in anti-PLA2R-negative patients (urine protein/creatinine ratio 7.922 ± 3.985 g/g vs. 4.318 ± 3.304 g/g, P = 0.001), and anti-PLA2R antibody level was positively correlated with proteinuria. The incidence of chronic kidney disease stage ≥ 3 was higher in anti-PLA2R-positive patients compared with anti-PLA2R-negative patients (P = 0.004). The probabilities of spontaneous remission were higher in anti-PLA2R-negative patients compared with anti-PLA2R-positive patients (P < 0.001). Multivariate analysis demonstrated that anti-PLA2R antibodies are an independent risk factor for developing chronic kidney disease stage ≥ 3 and for not reaching spontaneous remission.

Conclusion: Detection of anti-PLA2R antibodies at diagnosis in patients with primary MN can predict prognosis and guide treatment decisions.

Keywords: Membranous nephropathy; Phospholipase A2 receptors; Prognosis.

Figure 1. Prevalence of anti-PLA2R ab in patients with membranous nephropathy (MN)

Anti-PLA2R ab, anti-phospholipase A2 receptor antibody; SLE, systemic lupus erythematosus; UPCR, urine protein/creatinine ratio.

Figure 2. Correlation analysis between anti-PLA2R ab level and proteinuria and serum albumin level of patients with primary membranous nephropathy (A and B) and of anti-PLA2R-positive patients (C and D)

Anti-PLA2R ab, anti-phospholipase A2 receptor antibody; UPCR, urine protein/creatinine ratio.

Figure 3. Kaplan–Meier analysis of anti-PLA2R ab level and cumulative probability of chronic kidney disease (CKD) stage 3 or more (A), complete remission (B), and spontaneous remission (C)

Anti-PLA2R ab, anti-phospholipase A2 receptor antibody.