Anti-phospholipase A2 receptor antibody screening in nephrotic syndrome may identify a distinct subset of patients with primary membranous nephropathy

Purpose We sought to investigate the utility of anti-PLA2R antibody as a non-invasive screening method for the diagnosis of primary MN in patients with nephrotic syndrome (NS). Methods All consecutive patients with NS admitted in our department, between 01.01.2015 and 31.12.2019 were screened for anti-PLA2R antibodies by an ELISA assay (EUROIMMUN, Lübeck, DE). A positive anti-PLA2R serology was defined as an ELISA value over 2 RU/ml. Subsequently, all patients underwent kidney biopsy to confirm the histological diagnosis. Results Of the 203 patients with NS, we identified 67 patients with “high” titer of anti-PLA2R antibodies (> 20 RU/ml) and 47 patients with “intermediate” titer (2–20 RU/ml). In the entire cohort, the area under the curve (AUC) was 0.83 (95% CI 0.78–0.89; p