P0238LONG-TERM OUTCOME OF CHILDHOOD IDIOPATHIC NEPHROTIC SYNDROME

Abstract

Abstract Background and Aims Little is known about the long-term outcome of childhood idiopathic nephrotic syndrome (INS), in particular long-term complications, rate of relapses, frequency of prolonged steroid (S) and immunosuppressive treatment (IS). The choice of immunosuppressive drug remains discussed. Our aim was to study the long-term outcome in adulthood of patients with INS diagnosed during childhood. Method In this monocentric retrospective study, we included all adult patients (>18 years) admitted in our nephrology department between 2013 and 2019 with INS diagnosed during childhood. Patients who reached ESRD during childhood were excluded. Data regarding the outcome in adulthood were obtained through clinical database and medical charts. Results Eighty-two patients (M/F = 2/1) were included. Sixty-height patients had steroid-sensitive nephrotic syndrome (SSNS), including 52 with steroid-dependant nephrotic syndrome (SDNS). The other 14 patients had steroid-resistant nephrotic syndrome (SRNS). The median age at diagnosis was 3.9 years (1.2-16.5). The median number of relapses during childhood was 12 (0-52), 0.9/patient/year. 89% of patients received IS therapy in addition to S during childhood: median number of successive therapeutic lines was 3 (0-10) per child. Median follow-up during adulthood was 4.6 (0.1-25) years. 67% of patients experienced at least one relapse during adulthood, with a median number of relapses of 0.53 (0-3.7)/patient/year. Risk of relapse during adulthood was significantly associated with the total number of relapses during childhood (p=0.015) and with the number of relapses per year during childhood (p=0.007). 45% of patients received IS in addition to S during adulthood, mainly mycophenolate mofetil (23/82), calcineurin inhibitors (21/82) and rituximab (12/82). High blood pressure was observed in 22% of patients. At last follow-up, median eGFR was 90 (64-117) mL/min/1.73m in SSNS patients, 86 (57-126) mL/min/1.73m in SDNS patients and 70 (23-113) mL/min/1.73m in SRNS patients. Only 4/82 patients presented with eGFR lower than 60 mL/min/1.73m. Among them, 3 had SRNS. Only 1 thrombo-embolic event and 3 severe infections were reported. Bone densitometry was performed in 26 adult patients and osteopenia was found in 19 of them (73%). Conclusion The incidence of relapses in adulthood was relatively high in our study. However bias related to inclusion criteria could play a role. Whereas renal function remained normal in most patients, high blood pressure and osteopenia were frequent but major complications were rarely reported.