Pseudomonas aeruginosa bacteremia in a dialysis unit. 11. Relationship to reuse of coils.

Blood for culture was obtained over a six week period from 17 patients undergoing long-term hemodialysis. Bacteremia was detected during 18 of 201 dialyses. Blood drawn during fifteen of these dialyses contained pseudomonas aeruginosa. Ten of the 17 patients (59 per cent) had a Pseudomonas bacteremia some time during the study. Only one patient was symptomatic. The frequency of positive cultures was related to reuse of coils. No cultures were positive until after the fifth use, but by the tenth use, 41 per cent of the dialyses were associated with bacteremia. All coils that were used repeatedly and 32 of 48 of those used only once, grew Ps. aeruginosa when filled with media and incubated. This suggests that the coils were inoculated during dialysis and that benzalkonium chloride, the sterilizing agent, was unable to eradicate this organism. With repeated uses, the number of residual bacteria in the coil became large enough to cause detectable bacteremia during dialysis.