Plasma exchange in two cases of minimal change nephrotic syndrome with acute renal failure

One idiopathic and one nonsteroidal anti-inflammatory drug associated case of minimal change nephrotic syndrome with acute renal failure are described. Both patients were severely ill and needed dialysis. Treatment with corticosteroids and azathioprine for 19-21 days was ineffective. After start of plasma exchange treatment both patients rapidly recovered. The suggested effect of plasma exchange in these conditions can hardly be ascribed only to correction of the colloid oncotic pressure. An elimination of a circulating factor(s) of pathogenetic importance must also be suspected.