[Microbiological evaluation of two different disinfection protocols of a new hemodialysis monitor with an ultrafilter]. / Valutazione microbiologica di due diversi protocolli di disinfezione di un nuovo monitor di dialisi dotato di ultrafiltro sul dialisato.

BACKGROUND: Hemodialysis monitors represent a frequent site for bacterial contamination. METHODS: Two different disinfection protocols on a new device (Formula(R), Bellco) have been compared: only chemical or chemical plus heat disinfection by means of CFU, and LAL test. The endotoxin removing capacity of ultrafilter was tested with varying lipopolysaccharide concentrations. RESULTS: Similar results were obtained with heat disinfection compared to chemical disinfection (CFU and LAL test). The LAL test (chromogenic and gel-clot) showed that the ultrafilter performance decreased with use and was significant after 200 operating hours. CONCLUSIONS: Heat disinfection between dialysis shifts and chemical disinfection at the end of the day exclude bacterial contamination of the monitor as well as chemical disinfection; LAL test is a useful and simple tool to assess the ultrafilters performance in each Center.