ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effects of ultrapure water on the levels of oxidative stress and inflammation parameters in maintenance hemodialysis patients.</p><p><b>METHODS</b>Thirty-six stable maintenance hemodialysis patients were involved in this study, who were free of acute infection, vasculitis or disease activity and on hemodialysis therapy for at least 3 months before using ultrapure water. The parameters including serum advanced oxidation protein products (AOPP), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), myeloperoxidase (MPO), albumin (Alb), C-reactive protein (CRP), neopterin , tumor necrosis factor (TNF)-alpha, and interleukin (IL)-6 were measured before and 6, 12 months after use of ultrapure water, respectively.</p><p><b>RESULTS</b>After modification of the water management system, the microbial counts and endotoxin concentration decreased significantly (P<0.01). During the study period, the levels of the measured parameters gradually improved, showing significant difference between the time points of measurement (P<0.05). Use of ultrapure water for 6 months significantly improved serum AOPP, MDA, GSH-Px, MPO, Alb, CRP, neopterin, and TNF-alpha levels (P<0.05), and the level of IL-6 was further reduced after 12 months (P<0.05). Serum MPO activity was closely correlated with AOPP (r=0.335, P<0.05) and CRP (r=0.369 or 0.347, P<0.05) before or after use of ultrapure water.</p><p><b>CONCLUSIONS</b>Ultrapure water can improve the status of oxidative stress and inflammation in maintenance hemodialysis patients. Serum MPO activity may help estimate the levels of oxidative stress and inflammation.</p>