Effectiveness of microwave moist-heat intraluminal disinfection of CAPD connectology

Studies were performed to quantify the microbial population reduction achieved with the Peritoneal Dialysis Moist Heat Device (PDM-1). This microwave method is used to disinfect the inner lumen of connectors used in the exchange process for continuous ambulatory peritoneal dialysis (CAPD). The microwave heating technique was evaluated on different connector systems containing a suspension of 10(6) microorganisms. The most prevalent and most problematic peritonitis-causative microorganisms were tested. After heating, the degree of disinfection was measured by enumerating bacterial colonies of the treated suspension. D-value determinations were then performed. The D-value for spores of A. niger was found to be 7.1 seconds for one type of connector system. Two other connector systems containing different intraluminal solution volumes were also tested using spores of A. niger and D-values were determined to be 7.6 seconds and 9.5 seconds, respectively. Other organisms tested were determined to have D-value times shorter than that for A. niger. Rapid heating of the solution contained within the CAPD connectors is a key characteristic of the microwave technique since temperatures rise high enough for destruction of microorganisms while leaving the plastic safe to touch. Thus, this technique is a safe and effective method for providing intraluminal disinfection.