Many important aspects of the therapeutic approach to patients with
idiopathic membranous nephropathy are still controversial. There are several reports that the effectiveness of
therapy depends on histological staging and severity of interstitial mononuclear cell infiltration. We used several different treatments in 39 patients with stage II to III primary
membranous nephropathy with
proteinuria more than 2.5 g/d, without
hypertension and
chronic renal failure at biopsy. Ten patients were not treated, 13 were treated with only
steroids, 13 with alternate use of
steroids and
chlorambucil, and three with
cyclosporine A. The follow-up period was 5 to 10 years. Statistics included Kruskall-Wallis and one-way ANOVA analysis. A significant decrease in
proteinuria was noted in patients treated with
steroids (P < 0.01), from 8.45 +/- 1.04 g/d (mean +/- SEM) to 1. 42 +/- 0.45 g/d after follow-up of 5 years and in patients treated with
steroids and
chlorambucil (12.9 +/- 2.4 g/d [mean +/- SEM] to 2. 46 +/- 1.38 g/d). Compared with patients treated with
steroids (15. 3%) and patients treated with
steroids and
chlorambucil (15.3%), untreated patients had a high frequency of
chronic renal failure after 5 years of follow-up (70%) and had a significant increase in mean serum
creatinine (P = 0.008). We conclude that
steroid therapy alone, or associated with
chlorambucil, is effective in patients with stage II to III
membranous nephropathy. Patients responded with a decrease of
proteinuria and stable renal function during the long-term follow-up period. The group of patients treated with
cyclosporine A was too small to analyze.