PLA2R1 and nephrotic syndrome: Primary membranous nephropathy (MN) is a common cause of nephrotic syndrome in adults, and circulating anti-phospholipase A2 receptor (PLA2R) antibodies have emerged as a key diagnostic biomarker. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, we conducted a systematic review of eight studies evaluating serum PLA2R antibody testing against kidney biopsy, with sample sizes ranging from 117 to 670 participants.