This AAMI Standard (a revision of RD52) provides guidance for dialysis practitioners or providers on the minimum quality requirements for dialysis fluids used in hemodialysis and related therapies. It doesn’t include water and concentrate requirements.  It also excludes sorbent-based dialysis fluid regeneration systems, prepackaged solutions for continuous renal replacement therapy, and solutions for peritoneal dialysis.

Water quality used to prepare dialysis fluids must meet 13959 and acid and bicarbonate concentrates must comply with 13958.  The quality requirements for dialysis fluid collected as close to the inlet of the dialyzer is as follows:

Microbiological Level Standard Dialysis Fluid
Maximum Allowable Level Action Level
Colony Forming Units < 100 CFU/mL ≥ 50 CFU/mL
Endotoxin Units < 0.50 EU/mL ≥0.25 EU/mL

 

Relating to dialysis fluid quality, this latest Standard provides a US deviation to ISO 11663:2014.  In regards to testing compliance with microbiological requirements, the latest ISO Standards read: “Culture media shall be tryptone glucose extract agar (TGEA) or Reasoner’s 2A supplemented with 4 % sodium bicarbonate, or equivalent. Blood or chocolate agar shall not be used. Incubation temperatures of 17 °C to 23 °C, and an incubation time of 168 h (7 d) are recommended. Other test methods may also be used, provided such methods have been appropriately validated and compared to the cited methods.”

That wording has been replaced in the ANSI/AAMI 11663:2014 with the following:

“Approved culture methods shall include one of the following:

1)   tryptone glucose extract agar (TGEA) or Reasoner’s 2A supplemented with 4% sodium bicarbonate, or equivalent. Blood or chocolate agar shall not be used. Incubation temperatures of 17°C to 23°C, and an incubation time of 168 h (7 d); or

2)   Trypticase soy agar (TSA, a soybean casein digest agar) or standards method agar and plate count agar (also known as TGYE), incubated at 35°C for 48 hours.

Other test methods may also be used, provided such methods have been appropriately validated and compared to the cited methods. See USP <1231> for guidance on adoption of alternative methods.”

This deviation of test methods surrounding agar medium, incubation temperature and incubation time was not adopted by ISO, but is now found within the latest ANSI/AAMI 11663 document as a deviation.

It concludes with providing some rationale and historical perspective of how the microbial limits were developed.  Reference tables for 13959 for AAMI limits are also included.