Immunosuppressive therapy with cyclophosphamide and prednisolone in severe idiopathic membranous nephropathy.

In idiopathic membranous nephropathy (IMN) immunosuppressive therapy should be reserved for patients with potential risk factors at baseline or who show a progressive course. Cyclophosphamide pulse therapy (CPT) in IMN is not yet widely tested. We carried out a trial of CPT combined with conventional treatment in a group of patients with IMN at a greater risk. The study group consisted of 36 nephrotic adult IMN patients (M, 26; F, 10) with various combinations of risk factors. Mean proteinuria was 11.3 g/day, 47% patients were hypertensive, 78% had tubular changes, and 36% had focal glomerulosclerosis. They were treated with CPT and/or conventional low-dose cyclophosphamide and prednisolone. Median duration of immunosuppression was 14 months and median total cumulative dose of cyclophosphamide 172 mg/kg body weight. At 6 months (6m) remission was achieved in 44% cases and at the 36th month in 73%. None of the patients developed moderate or severe renal failure. Side-effects were minimal. Multivariate analysis of baseline data and the changing course of the disease during therapy showed that tubular changes (P = 0.0025), creatinine clearance at baseline (P = 0.04) and at 6m (P = 0.02), and proteinuria at 6m (P < 0.0001) significantly influenced the therapeutic effect. We conclude that cyclophosphamide (including pulse) and prednisolone can bring significant remission and maintain renal function in IMN with potential risk factors.