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Updated: Jan 30, 2026

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Published on: October 2, 2020
Ultrapure Filter does not Confer Short-Term Benefits over Two Reverse Osmosis Systems in Chronic Hemodialysis
Ayelet Grupper1, Moshe Shashar1, Talia Weinstein1
1Department of Nephrology, Tel Aviv Sourasky Medical Center, and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Background:
Dialysate purity contributes to the inflammatory response that afflicts hemodialysis patients.
Objectives:
To compare the clinical and laboratory effects of using ultrapure water produced by a water treatment system including two reverse osmosis (RO) units in series, with a system that also includes an ultrapure filter (UPF).
Methods:
We performed a retrospective study in 193 hemodialysis patients during two periods: period A (no UPF, 6 months) and period B (same patients, with addition of UPF, 18 months), and a historical cohort of patients treated in the same dialysis unit 2 years earlier, which served as a control group.
Results:
Mean C-reactive protein, serum albumin and systolic blood pressure worsened in period B compared to period A and in the controls.
Conclusions:
A double RO system to produce ultrapure water is not inferior to the use of ultrapure filters.
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