In a prospective study, the effectiveness of a newly available peroxyacetic acid solution (Dialox) as a cleansing and sterilizing agent for the reuse of conventional hollow-fiber hemophan dialyzers was evaluated. The effects of reprocessing dialyzers with peroxyacetic acid on leukocyte and platelet counts, dialyzer performance, acute intradialytic symptoms and cost effectiveness were studied. A total of 250 sessions using new dialyzers and 3,227 sessions employing reused dialyzers were monitored. Dialyzers were withdrawn after a maximum of 21 sessions, and the mean number of uses was 13.9 +/- 5.1. It was found that peroxyacetic acid reprocessing of hemophan dialyzer membranes improved hemodialysis leucopenia and thrombocytopenia. It was also proved that, compared to new ones, the reused dialyzers were associated with significantly fewer intradialytic symptoms. Clearances of small molecules and ultrafiltration rate after multiple dialyzer reprocessing remained within the acceptable limits. The duration of hemodialysis has been prolonged 30 min after the 10th dialyzer reuse and dialysis adequacy remained unaffected. About 100,000 DEM were saved during the one year due to the reuse procedure. The authors conclude that automated dialyzer reprocessing with peroxyacetic acid as a sole cleansing and sterilizing agent is a safe, efficacious and money-saving method.