Original Article Long-term Treatment of Minimal-change Nephrotic Syndrome with Cyclosporin: A Control Biopsy Study

Abstract. Seven patients with minimal-change nephrotic syndrome confirmed by renal biopsy were treated with cyclosporin (CsA). Four patients had frequent relapses and three others had primary steroid resistant nephrotic syndrome. Corticosteroids were discontinued as soon as CsA whole blood trough values of 200-500 ng/ml (RIA method) were reached. A full remission, defined as com-plete disappearance of proteinuria, was achieved in five patients under this treatment. In the two other patients proteinuria was reduced. Two patients experienced an acute episode of dose-dependent nephrotoxicity; however, overall renal func-tion, as determined by the creatinine clearance, was stable. Control biopsies in five patients after a mean treat-ment period of 10 months showed no significant vascular or interstitial toxicity. Key words: Cyclosporin; Cyclosporin nephrotoxicity; Minimal-change nephrotic syndrome; Kidney biopsies; Steroid-dependent nephrotic syndrome; Steroid-resistant nephrotic syndrom