Pre‐transplant angiotensin receptor II type 1 antibodies and risk of post‐transplant focal segmental glomerulosclerosis recurrence

Post‐kidney transplant recurrence of focal segmental glomerulosclerosis (FSGS) is a major problem. AT1R is expressed on podocyte; its expression is elevated in the proteinuric state. Using an ELISA, we tested pre‐transplant sera of 28 patients with history of idiopathic FSGS for anti‐AT1R levels and serum soluble urokinase‐type plasminogen activator receptor (suPAR) as a biomarker for risk of recurrence of FSGS. Sera from 11 patients with polycystic kidney disease (PKD) were used as controls. Twelve patients had biopsy proven post‐transplant FSGS recurrence at 1.5 months. No difference was found in the pre‐transplant suPAR levels of FSGS patients (5993 ± 2292 pg/mL) vs. PKD (7334 ± 4538 pg/mL) (p = 0.23). Serum suPAR levels in patients with FSGS recurrence (5786 ± 1899 pg/mL) vs. no FSGS recurrence (6149 ± 2598 pg/mL) (p = 0.69) were not different. Anti‐AT1R levels in patients with FSGS were 12.66 ± 11.85 U/mL vs. 8.69 ± 6.52 U/mL in PKD (p = 0.32); however, a difference was found in patients with and without FSGS recurrence 20.41 ± 14.36 U/mL 6.84 ± 4.181 U/mL, respectively (p < 0.01). Area under curve for suPAR and anti‐AT1R to predict post‐transplant FSGS recurrence was 0.51 and 0.84, respectively. Pre‐transplant anti‐AT1R levels appear to be a helpful biomarker in identifying patients at high risk of post‐transplant FSGS recurrence.