Management of idiopathic membranous nephropathy: evidence-based recommendations.

Membranous nephropathy is a frequent cause of nephrotic syndrome in adults, and in one third of these patients, it leads to end-stage renal disease. Based on an extensive critical review of the literature, the following recommendations are offered. Oral high-dose corticosteroids are ineffective in producing either a sustained remission of nephrotic syndrome or in preserving renal function in patients with membranous nephropathy, and should not be used as the sole therapy (grade A recommendation). The use of azathioprine is not associated with any significant benefits, so its use is not justified (grade C). The alkylating agents cyclophosphamide and chlorambucil are both effective in the management of membranous nephropathy. Because of growing concern about long-term toxicity, especially with cyclophosphamide, these drugs should be reserved for patients who exhibit clinical features, such as severe or prolonged nephrosis, renal insufficiency, or hypertension, that predict a high likelihood of progression to end-stage renal disease. Chlorambucil in conjunction with oral steroids is the drug of first choice (grade A). Cyclophosphamide and oral steroids are alternatives (grade B). Cyclosporine may, in the future, become the agent of choice for membranous nephropathy. Currently, it is recommended (grade B) that cyclosporine use be considered in patients at high risk for progression in membranous nephropathy or if alkylating agents are contraindicated or ineffective.