2024 Volume 59 Issue 4 Pages 329-335
Post-transplant recurrence of focal segmental glomerulosclerosis (FSGS) is a major challenge in the field of kidney transplantation, because it is a known risk factor of graft failure. The risk of recurrence is particularly high in patients with primary FSGS, which is supposed to be caused by circulating factors. By contrast, recipients with secondary (adaptive, viral, and drug-induced) FSGS and genetic FSGS have a very low risk of FSGS recurrence. Therefore, it is very important to determine the cause of FSGS before kidney transplantation. When secondary FSGS is excluded based on past histories and physical examinations, genetic testing should be considered. In our analysis of FSGS patients with an age 1-15 years at onset, patients who met all of the following criteria had no pathogenic variants in genes associated with FSGS: (i) nephrotic syndrome, (ii) complete or partial remission with initial steroid therapy and/or additional immunosuppressive therapies, and (iii) diffuse foot process effacement on electron microscopy in the native kidney biopsy. By contrast, >90% patients who failed to meet at least one of the criteria had pathogenic variants in FSGS-associated genes. Therefore, genetic testing is highly recommended in such patients. In summary, adequate assessment of post-transplant recurrence risk and genetic diagnosis can guide individualized strategies for FSGS patients undergoing kidney transplantation, including pre-transplant prophylactic treatment.