Stepwise Treatment Using Corticosteroids Alone and in Combination with Cyclosporine in Korean Patients with Idiopathic Membranous Nephropathy

Abstract

PurposeWe undertook an observational study to investigate the effects of immunosuppressive treatment on proteinuria and renal function in 179 Korean idiopathic membranous nephropathy patients with nephrotic syndrome.Materials and MethodsThe primary outcome was regarded as the first appearance of remission and the secondary outcomes as a decline in estimated glomerular filtration rate (eGFR) >50% or initiation of dialysis, and all-cause mortality. Seventy-two (40.2%) and 50 (27.9%) patients were treated with corticosteroids alone (C) and corticosteroids plus cyclosporine (C+C), respectively, whereas 57 (31.8%) did not receive immunosuppressants (NTx). Cyclosporine was added if there was no reduction in proteinuria of >50% from baseline by corticosteroids alone within 3 months.ResultsThere were no differences in baseline renal function and the amount of proteinuria among the three groups. Overall, complete remission (CR) was achieved in 88 (72.1%) patients by immunosuppressants. In a multivariate analysis adjusted for covariates associated with adverse renal outcome, the probability of reaching CR was significantly higher in the C [hazard ratio (HR), 4.09; p<0.001] and C+C groups (HR, 2.57; p=0.003) than in the NTx group. Kaplan-Meier analysis revealed that 5-year CR rates of C, C+C, and NTx groups were 88.5%, 86.2%, and 56.7% (p<0.001). Ten-year event-free rates for the secondary endpoints in these three groups were 91.7%, 79.9%, and 57.2% (p=0.01).ConclusionImmunosuppressive treatment was effective in inducing remission and preserving renal function in these patients. Therefore, stepwise treatment using corticosteroids alone and in combination with cyclosporine is warranted in these patients.