Ultrapure Dialysate: What, How, and Why

Dialysate is a blend of water and chemicals that washes wastes and fluid out of the blood. During a treatment, dialysate comes in contact with your blood through the dialyzer membrane. So, it must be high quality to keep you safe.

Bacteria live in the tap water used to make dialysate. Live bacteria can grow and form colonies. Dead bacteria form endotoxin, which causes inflammation. Chronic inflammation can damage tissues, like your heart.

Per current AAMI guidelines*, dialysate can have no more than 200 colony-forming units (CFU) of bacteria and 2 endotoxin units (EU) per milliliter (mL). 1 These limits may prevent pyrogenic (fever) reactions, but they are not low enough to stop chronic inflammation. A 3 hour treatment with most machines will use 90 liters of dialysate. At the standard level, this could have as many as 18 million CFUs of bacteria.

* Medicare has not yet approved use of the new AAMI standards. Their standard is 200 CFUs of bacteria for water, and 2,000 CFUs of bacteria for dialysate.

How ultrapure dialysate is made

Ultrapure dialysate is made with very pure water. A series of water treatment machines, each with a different function, is needed to make water this pure. The dialysate must also pass through an ultrafilter, 1 which takes out particles like bacteria and endotoxin. Per AAMI Guidelines, ultrapure dialysate must have less than 0.1 CFU per mL (2,000 times less than the AAMI standard level). Standards in Europe are even more strict. 2 At these low levels, the risk of chronic inflammation is much less. 3,4,5

Benefits of Ultrapure Dialysate

For you, studies show that using ultrapure dialysate may mean:

For example, a year-long cross-over study compared standard and ultrapure dialysate. Thirty-four patients were split into two groups. Each group had 6 months of treatment with standard and 6 months of treatment with ultrapure dialysate. Ultrapure dialysate led to less inflammation, lower EPO doses, and better use of iron. 6

If you have some kidney function, you may keep it longer with ultrapure dialysate. A 2-year study randomly assigned 30 new patients to standard or ultrapure dialysate. Kidney function dropped in both groups—but was significantly worse for those on standard dialysate. 8


It's common sense to want fewer bacteria in your blood, and research supports that ultrapure dialysate has some pluses. Some clinics do not support its use because ultrapure dialysate costs more, 5 but other clinics do offer it—ask about your machine if you're not sure.

New technology allows some home machines to offer built-in filters to purify the dialysate to ultrapure or near-ultrapure levels. These include the:

One of the unsung benefits of home dialysis may be a chance to reduce your risk of chronic inflammation. It's something more to think about when you choose a treatment.


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