Sterile versus non-sterile dialysis fluid in chronic hemodialysis treatment.

As the quality of water in the dialysis fluid varies considerably, and in view of the fact that endotoxin or active derivatives can cause acute side effects in patients, the dialysis fluid must be sterile. Therefore, we introduced ultrafiltration of dialysis fluid before entering the dialyzer. Fifteen patients, (ten women, five men) were treated for 4 weeks with nonsterile, and then with sterile dialysis fluid. The bacterial loading in the dialysis fluid before hemodialysis was 1.34 X 10(5)/ml, and after hemodialysis 2.9 X 10(3)/ml; the endotoxin concentration was high and varied between less than 1 EU/ml and greater than 10 EU/ml before and after hemodialysis. After ultrafiltration of the dialysis fluid by a polyamide hollow fiber membrane, all samples were free of bacteria and the concentration of endotoxin was lower than the detectable limit (less than 0.03 and less than 0.5 EU/ml). With ultrafiltration of dialysis fluid we can obtain sterile dialysate, which is endotoxin free. Interleukin-1 and tumor necrosis factor in the patients with ultrafiltration was significantly lower than without ultrafiltration.