Background: Focal Segmental Glomerulosclerosis (FSGS) recurrence after kidney transplantation (KTx) is reported to be 20–65%, with a higher frequency of early graft loss compared to other diseases.
Aim: To analyze the outcome of KTx in children with biopsy-proven FSGS as the cause of ESRD; to assess incidence and risk factors of recurrence and efficacy of treatment.
Materials and Methods: Records of all transplants between November 1988 and November 2017 at Hospital JP Garrahan were reviewed. Post-KTx recurrence of nephrotic syndrome (NS) was defined as proteinuria: >40 mg/m2/hour or UP/Cr >3.5 and remission, as proteinuria <10 mg/m2/hour or UP/Cr <0.2.
Results: From December 1988 to September 2016, 83/861 transplants were performed in 76 children with ESRD due to primary FSGS; 64 (77%) from deceased donors and 23 (23%) from living-related donors. Mean age at KTx was 11.4±4 years. Mean time of follow-up: 62±47 RIQ: 24-92 months. Patient survival at 1, 3, 5, 7 and 10 years was worse in patients with FSGS compared to other ESRD etiologies: 98%, 93%, 89%, 89 % and 89% vs 99%, 97.6%, 96%, 96% and 95%  respectively. Median graft survival was also worse (7.3 vs 13.6 years; p<0.0001). Causes of death were: Bacterial sepsis 80% (n=4) and Death with a functioning graft 20% (n=1). Grafts were lost because of: Chronic rejection 40% (n=16), Recurrence of NS 17.5% (n=7), Recurrence of NS and AR 17.5% (n=7), Thrombosis 12.5% (n=5), Death with a functioning graft 7.5% (n=3), Acute Rejection 5% (n=2). Incidence of biopsy-proven early acute rejection (from 2001; 1st. 90 days) and DGF were higher: 25% vs 12.7%; (p=0.02) and 34.5% vs 17.2%; (p<0.001). Relapse rate was 63% (n=50): 64% in days 1 and 2 (n=32), 28% from day 2 to 7, (n=14), and 8 %, during the first month post KTx (n=4). No difference in age at onset of disease, time to ESRD, or type of induction was found between those who relapsed and those who didn’t. Graft survival at 1, 5, and 10 years in patients who relapsed and remitted (n=21) was similar to those with no recurrence (n=30): 86%, 83%, and 43% vs 90%, 73.5%, and 37% (p=0.57); mean eGFR was at last visit was 38±4 and 43±5 ml/min/1.73 m2 (p=0.37). Plasmapheresis (PP) was given to 27 patients for treatment of relapse, and from 2013, 18 patients received pre-KTx PP and Rituximab. In this last group, risk of graft failure was lower (HR: 0.39; CI95%: 0.16-0.96 p=0.01). Graft survival at 1 and 3 years was 63% and 43% vs 89% and 74% (p=0.10)
Conclusion: Patients with FSGS had worse patient and graft survival compared to those with other ESRD etiologies, and a higher Incidence of DGF and AR. FSGS patients with remission had a graft-survival rate similar to those with other etiologies of ESRD. Combined pre-KTx PP and Rituximab may be a better treatment option.