Recurrence of idiopathic focal segmental glomerulosclerosis after kidney transplantation: Experience of a Korean tertiary center

FSGS is the second most common cause of idiopathic NS in children. It often progresses to ESRD and commonly recurs after KT. To investigate the risk factors and the prognosis of recurrence in pediatric idiopathic FSGS in Korea, retrospective review of 43 KT in 38 children with idiopathic FSGS of last two decades was conducted. The patients presented at the median age of 5.1yr (range 1.1-13.8yr) and received KT 5.7yr later (range 1.3-17.6yr). FSGS recurred in 20 allografts immediately after transplantation, only in those who presented with NS but not in those who presented with AUA. The risk factors for recurrence were age of onset >5yr and progression to ESRD within sixyr but not sooner than 18months. CR was achieved in 13 patients with FSGS recurrence and sustained in nine without subsequent relapse over a median of six and a halfyr (0.6-20.7yr). Pediatric idiopathic FSGS presenting with NS recurred in more than half of patients after transplantation. Interestingly, more rapid progression within less than 18months did not predict recurrence. To identify high-risk patients of recurrence, an international cooperative study would be necessary.