Spontaneous remission of nephrotic syndrome in membranous nephropathy with chronic renal impairment.

BACKGROUND: Spontaneous remission (SR) of nephrotic syndrome, in the absence of immunosuppressive treatment, is relatively common among patients with idiopathic membranous nephropathy (IMN) and normal renal function. However, it has not been reported in patients with chronic renal impairment. METHODS: All patients with IMN who had developed SR in the presence of chronic renal insufficiency were identified among the nephrology departments that belong to the Spanish Group for the Study of Glomerular Diseases (GLOSEN). Their characteristics and outcome after SR were studied. RESULTS: Eleven patients were identified. All of them showed renal insufficiency and nephrotic syndrome at the time of renal biopsy. Serum creatinine (Scr) continued to increase in the following months, reaching a peak value of 2.6 ± 1.5 mg/dL (range 1.7-6.5). Angiotensin converting enzyme inhibitors or spironolactone were prescribed in 10/11 patients at renal biopsy or shortly after it. Nephrotic proteinuria persisted during the first months of follow-up, but it started to spontaneously decrease 12 ± 7 months (2-30 months) after renal biopsy. Finally, complete (nine patients) or partial (two patients) remission of nephrotic syndrome was observed. Coinciding with proteinuria remission, renal function tended to improve. Nephrotic syndrome relapsed in two patients, accompanied by a rapid deterioration of renal function. In the remaining nine patients, remission persisted throughout a follow-up of 146 ± 64 months. Mean Scr at the last visit was 1.9 ± 0.9 mg/dL and proteinuria 0.2 g/24 h. CONCLUSION: SR of nephrotic syndrome can also be observed in membranous nephropathy patients exhibiting chronic renal impairment.

Spontaneous remission of nephrotic syndrome in idiopathic membranous nephropathy.

Spontaneous remission is a well known characteristic of idiopathic membranous nephropathy, but contemporary studies describing predictors of remission and long-term outcomes are lacking. We conducted a retrospective, multicenter cohort study of 328 patients with nephrotic syndrome resulting from idiopathic membranous nephropathy that initially received conservative therapy. Spontaneous remission occurred in 104 (32%) patients: proteinuria progressively declined after diagnosis until remission of disease at 14.7 +/- 11.4 months. Although spontaneous remission was more frequent with lower levels of baseline proteinuria, it also frequently occurred in patients with massive proteinuria: 26% among those with baseline proteinuria 8 to 12 g/24 h and 22% among those with proteinuria >12 g/24 h. Baseline serum creatinine and proteinuria, treatment with angiotensin-converting enzyme inhibitors or angiotensin receptor antagonists, and a >50% decline of proteinuria from baseline during the first year of follow-up were significant independent predictors for spontaneous remission. Only six patients (5.7%) experienced a relapse of nephrotic syndrome. The incidence of death and ESRD were significantly lower among patients with spontaneous remission. In conclusion, spontaneous remission is common among patients with nephrotic syndrome resulting from membranous nephropathy and carries a favorable long-term outcome with a low incidence of relapse. A decrease in proteinuria >50% from baseline during the first year predicts spontaneous remission.