Ultrafiltration and endotoxin removal from dialysis fluids.
Biocompatibility in hemodialysis is now regarded as a multifactorial problem and dialysate represents a main risk. Pyrogenic fractions mostly coming from gram-negative bacteria easily pass through dialysis membrane, either by backdiffusion or by backfiltration, and induce blood cell activation. To demonstrate the long-term efficiency of a 2 m2 polyamide ultrafilter in producing a pyrogen free solution, we used an experimental circuit ultrafiltering for 240 hours (500 ml/min) a bicarbonate dialysate contaminated (5 to 48 EU/ml) by a Pseudomonas aeruginosa filtrate. The efficiency was monitored by LAL-test and IL-1 PBMC so to detect not only lipid A containing endotoxins but also other cytokines inducing bacterial fractions. At the post-ultrafilter sampling port the LAL-test was < 0.005 to 0.034 EU/ml; IL-1 PBMC was below the detection limit (20 pg/ml) being 27 to 63 pg/ml at the pre-ultrafilter level. Polyamide ultrafiltration represents an efficient system to obtain an endotoxin-free dialysate and a single filter works up to 240 hours.
Di Felice
A
A
Department of Nephrology, University of Modena, Bellco Laboratories, Bellco Spa, Italy.
Cappelli
G
G
Facchini
F
F
Tetta
C
C
Cornia
F
F
Aimo
G
G
Lusvarghi
E
E
D002478:Cells, Cultured; D004340:Drug Contamination; D004731:Endotoxins / Q000302:isolation & purification*; D015312:Hemodialysis Solutions; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008567:Membranes, Artificial; D008970:Molecular Weight; D011749:Pyrogens / Q000302:isolation & purification; D006435:Renal Dialysis; D014462:Ultrafiltration
D004731:Endotoxins; D015312:Hemodialysis Solutions; D007375:Interleukin-1; D008567:Membranes, Artificial; D011749:Pyrogens