LONG-TERM EVOLUTION OF UNTREATED IDIOPATHIC MEMBRANOUS GLOMERULONEPHRITIS

The indication for immunosuppressive treatment in idiopathic membranous glomerulonephritis is a very controversial issue, due to the variable evolution of this nephropathy Study of the spontaneous evolution of untreated cases should permit us to define high-risk groups in which these treatment could be beneficial. We analyze the evolution of 46 patients (30 males, 16 females) who did not receive immunosuppresive treatment. Follow-up was 60 +/- 40 months. Presentation was with nephrotic syndrome with normal function in 39 patients, non-nephrotic proteinuria with normal renal function in 4 and nephrotic syndrome with renal insufficiency (RI) in 3. At the end of follow-up 26 patients maintained normal renal function (Group I). Twelve of them reached a complete remission and 11 a partial remission. Two patients with partial remission later relapsed. The time elapsed between diagnosis and onset of remission was 28 +/- 12 months. The remaining 20 patients developed progressive RI (Group II), nine cases being on dialysis at the end of follow-up. With the exception of two cases, the onset of RI was established within the first 30 months of evolution. There was a significant difference between the two groups regarding age, blood pressure and initial serum creatinine. A remarkable dual evolution in the long-term follow-up is observed, towards remission proteinuria (45.6 % of the patiens) or towards RI (43,5 %). Both evolutions were defined within the first 30 months in the majority of patients. Given the high incidence of spontaneous remissions we think that immunosuppressive treatments should be restricted to those patients that develop RI.