Efficacy of disinfectants and endotoxin retentive filters for the removal of bacterial DNA from dialysates

Background Bacterial DNA (bDNA) fragments in dialysate lines can trigger inflammatory responses in dialysis patients. However, no studies have reported the removal and inactivation of bDNA in dialysate lines using cleaning and disinfection, and management procedures to control bDNA contamination have yet to be established. Methods The efficiency of an endotoxin retentive filter (ETRF) for the removal of bDNA was examined using an experimental dialysate line incorporating an ETRF and the solubilized materials derived from hot-water-disinfected Pseudomonas aeruginosa cells. To examine the inactivation of bDNA by disinfection, Pseudomonas aeruginosa cell suspensions were disinfected with hot water, peracetic acid, or sodium hypochlorite, and the amount of bDNA remaining after the disinfection treatment was determined. Single-stranded and double-stranded bDNA were measured using Qubit® fluorometry. The molecular size of bDNA was analyzed by polyacrylamide gel electrophoresis. Results In the spike-and-recovery test of solubilized materials derived from hot-water-disinfected bacterial cells, bDNA leakage was observed when the circuit pressure of the inlet ETRF was elevated. bDNA was inactivated more during disinfection with sodium hypochlorite than with peracetic acid and hot water. Conclusions In addition to the ETRF, disinfection with sodium hypochlorite is an effective method for the management of bDNA in dialysates.