Background: Polymethyl methacrylate (PMMA) membranes have the unique property of adsorption, which can remove medium-and large-weight molecular substances that cannot be removed by normal hemodialysis and hemodiafiltration. Filtryzer® NF (NF) is a newly developed PMMA membrane that suppresses platelet adhesion on the membrane surface and retains an adsorption property. NF is expected to improve inflammatory conditions and clinical symptoms in hemodialysis patients compared with conventional PMMA membranes.Methods: Thirty-seven maintenance hemodialysis patients treated with polysulfone (PS) membranes and who had detectable chronic inflammation were enrolled into the study. The patients were randomly allocated into the NF and PS groups and observed for 1 year. C-reactive protein (CRP) values were measured as the primary endpoint. Nutrition, blood cell count, and dialysis itchiness were evaluated as secondary endpoints.Results: Significant differences in CRP values were not found between the NF and PS groups. In the PS group, the creatinine generation rate (%CGR) and platelet count, which were included in nutrition and blood cell count, respectively, significantly decreased after 6 and 9 months compared with the start of study, but these parameters did not significantly change in the NF group within 1 year. Dialysis itchiness in the NF group was significantly improved compared with the PS group after 9 months.Conclusions: Our results showed that a new PMMA membrane, NF, has a potential to maintain nutritional conditions and the platelet counts and improve dialysis itchiness.Trial registration: This study is retrospectively registered with the Clinical Trials Registry of the University Hospital Medical Information Network on February 17, 2015 (registration ID, UMIN000016567).

We applied the heat citric acid disinfection method in the main part of the central dialysis fluid delivery system (MPCDDS), which consists of a multiple-patient dialysis fluid supply unit, dialysis console units, and dialysis fluid piping. This disinfection method has been used for single-patient dialysis machines, but this is the first trial in the MPCDDS. We examined, by points of safety and disinfection effect, whether this disinfection method is comparable to conventional disinfection methods in Japan. The conventional disinfection method is a combination of two disinfectants, sodium hypochlorite and acetic acid, used separately for protein removal and decalcification. Consequently, total microbial counts and endotoxin concentrations fully satisfied the microbiological requirements for standard dialysis fluid of ISO 11663. From our results and discussion, this heat citric acid disinfection method is proved to be safe and reliable for MPCDDS. However, to satisfy the microbiological requirements for ultrapure dialysis fluid, further consideration for this method in MPCDDS including the reverse osmosis device composition and piping is necessary.