Long-term outcome and prognostic factors of idiopathic membranous nephropathy in the Chinese population

Idiopathic membranous nephropathy (IMN) is a representative form of nephrotic syndrome in China. Although IMN is thought to run a more benign course in Asian patients than in the Caucasian population, there has been no persuasive study to determine the long-term prognosis and risk factors for IMN in the Chinese population.A retrospective chart review. All patients admitted to Nanjing Institution of Nephrology from January 1985 to December 2007 with biopsy-proven IMN were enrolled. The primary outcome was the renal survival rate and risk factors at renal biopsy.A total of 217 patients were included in the study, and the overall renal survival rates were 96.9%, 93.5%, and 86.6% at 5, 10, and 15 years after renal biopsy, respectively. When the clinical features at biopsy were evaluated, patients with hypertension (p = 0.023), decreased eGFR (p < 0.001), nephrotic-range proteinuria (p = 0.047), elevated urinary NAG (p = 0.045) and RBP (p = 0.007) had a worse prognosis. Cox multivariate analysis showed that decreased eGFR and chronic tubulointerstitial lesion were independent risk factors for ESRF (end-stage renal failure).IMN is a disease with a comparatively good prognosis in the Chinese population, with a renal survival rate of more than 90% at 10 years after renal biopsy. Decreased eGFR at biopsy and chronic tubulointerstitial lesion are independent risk factors of ESRF. Partial or complete remission of proteinuria improved the prognosis.