Recurrence of primary focal glomerulosclerosis (FGS) after renal transplantation is associated with poor graft survival. Plasma exchange (PE) can reduce proteinuria and even induce complete remission of proteinuria. It is, however, unknown whether the use of PE therapy improves long-term graft survival. In our center, PE has been used to treat recurrent FGS after renal transplantation since 1994. Thus far, 13 patients have been treated with PE for recurrent FGS and followed for up to 77 months after the onset of the recurrence. We reviewed the transplantation data in these patients, and, for comparison, ten patients who underwent transplantation between 1973 and 1991 and were not treated with PE served as historical controls. Recurrence of FGS occurred within 4 weeks of transplantation in 74% of the patients. PE was started within 14 days of the onset of proteinuria in 85% of the patients. Two patients lost their graft within the first month of transplantation due to untreatable rejection; the remaining 11 patients (85%) achieved complete (n=7) or partial (n=4) remission. Seven patients remained in remission after a short period of treatment with PE (< or =18 sessions in 2 months), whereas four patients needed prolonged treatment (median of 58 sessions). The need for prolonged PE was associated with a late (>30 days after transplantation) recurrence of FGS (P=0.02). A comparison with the historical control group revealed not only a significant reduction in proteinuria, but also significantly better long-term graft survival in the treated group, 85% and 30%, respectively, at 5 years (P=0.02). In conclusion, PE is an effective form of treatment for recurrent FGS, especially if initiated early. Failure to maintain stable remission after the initial period of PE does not necessarily imply a poor outcome, and sustained remissions can be achieved after prolonged treatment.