Pre‐transplant phospholipase A2 receptor autoantibody concentration is associated with clinically significant recurrence of membranous nephropathy post‐kidney transplantation

Previous studies that have assessed the association of pre‐transplant antiphospholipase A2 receptor autoantibody (PLA2R‐Ab) concentration with a recurrence of membranous nephropathy (rMN) post‐kidney transplant have yielded variable results. We tested 16 consecutive transplant patients with a history of iMN for pre‐transplant PLA2R‐Ab. Enzyme‐linked immunosorbent assay titers (Euroimmun, NJ, USA) >14 RU/mL were considered positive. A receiver operating characteristic (ROC) analysis was performed after combining data from Quintana et al. (n = 21; Transplantation February 2015) to determine a PLA2R‐Ab concentration which could predict rMN. Six of 16 (37%) patients had biopsy‐proven rMN at a median of 3.2 yr post‐transplant. Of these, five of six (83%) had a positive PLA2R‐Ab pre‐transplant with a median of 82 RU/mL (range = 31–1500). The only patient who had rMN with negative PLA2R‐Ab was later diagnosed with B‐cell lymphoma. One hundred percent (n = 10) of patients with no evidence of rMN (median follow‐up = five yr) had negative pre‐transplant PLA2R‐Ab. In a combined ROC analysis (n = 37), a pre‐transplant PLA2R‐Ab > 29 RU/mL predicted rMN with a sensitivity of 85% and a specificity of 92%. Pre‐transplant PLA2R‐Ab could be a useful tool for the prediction of rMN. Patients with rMN in the absence of PLA2R‐Ab should be screened for occult malignancy and/or alternate antigens.