Hemodialysis is associated with chronic inflammation, an important part of a wide syndrome spectrum consisting of malnutrition, inflammation and atherosclerosis (MIA) associated with increased longterm morbidity and mortality in end-stage renal failure. Although the etiology of the MIA syndrome is multifactorial, microbiological contamination of the dialysate is believed to be an important factor. It hs been demonstrated that bacterial products in the dialysate can easily pass through the dialyser membrane and cause the secretion of inflammatory mediators via the stimulation of the immune system. Bacterial products have been shown to pass both through low-flux and high-flux dialysers and cause the secretion of cytokines such as TNF-α, IL-6 and IL-1 by stimulating mononuclear cells.
Forty-two patients (21 each in the study and patient groups) who were undergoing hemodialysis were included in this study. The study period was 6 months. Exclusion criteria were as follows; chronic infection, inflammation, malignancy and long-term antibiotic and steroid usage. Regular hemodialysis with ultrapure dialysate 3 times a week was performed in the study group, in whom a conventional dialysate was used previously. Hemodialysis with a conventional dialysate was continued in the control group patients, using other volumetric-controlled machines in the same unit.
This study demonstrated that there was no significant difference between the beginning and end levels of hsCRP and IL-6 in the control group, in whom standard dialysate was used for hemodialysis. On the other hand, hsCRP and IL-6 levels were found to be significantly decreased in the study group who underwent hemodialysis with ultrapure dialysate (p<0.01).
In conclusion; ultrapure dialysis decreases the inflammatory markers and consequently chronic inflammatory process in hemodialysis patients. Larger and long-term clinical studies are still needed to identify the long term effects of ultrapure dialysate on morbidity and mortality.