Table 3.

Microbiologic quality requirements of fluids used for hemodialysis and related therapies

Fluid Type	Viable Bacteria, CFU/ml		Endotoxin, EU/ml
	ISOa	FDAb	ISOa	FDAb
Water	<100	<200	<0.25	<5
Standard dialysate	<100	<2000	<0.5	—
Ultrapure dialysis fluid	<0.1	—	<0.03	—
Substitution fluid	Sterile	<10−6	Nonpyrogenic	<0.25

ISO, International Organization for Standardization; FDA, Food and Drug Administration; —, no level referenced in FDA Guidance document.

^aAs defined in ISO 11663:2014 (14).

^bMeeting the Association for the Advancement of Medical Instrumentation standard for water and dialysate and for substitution fluid, the United States Pharmacopeia (USP) standard for sterile water for injection as outlined in the FDA Guidance document on premarket notifications for hemodialysis delivery systems (8). The FDA Guidance document has not been updated since 1998, and the microbiologic quality requirements specified in that document may not be consistent with current standards (14).