Comparison of the fixative properties of five disinfectant solutions.

Following a French circular published in 2001, the use of glutaraldehyde for the disinfection of reusable medical devices was abandoned in favour of non-fixative disinfectants such as peracetic-acid-based solutions. Data published regarding the fixative properties of alternative disinfectants remain contradictory. We compared the effect of repetitive treatments of polytetrafluoroethylene (PTFE) tubes, contaminated by a liquid medium inoculated with Pseudomonas aeruginosa, using five different disinfectant solutions: two peracetic acid solutions (with and without an activator), glutaraldehyde, ortho-phthaldehyde and succine dialdehyde. The results confirmed that repeated treatments of a PTFE tube with a 2% glutaraldehyde solution induce an important accumulation and/or fixation of protein, compared to peracetic-acid-based disinfectants, for which the accumulation and/or fixation of proteins remain low and vary from one formulation to another.

[Evaluation of 7 endoscope washer-disinfectors: bactericidal activity of the disinfectants, antibacterial efficacity of paired washer-disinfector products]. / Evaluation de sept laveurs-désinfecteurs d'endoscopes: activité bactéricide des désinfectants, efficacité antibactérienne des couples laveur-désinfecteur/produits.

The authors studied seven automatic washer disinfectors for flexible endoscopes with two methods. The first method, a microdilution method, studied the bactericidal activity of the seven disinfectants against 21 strains: four reference strains, 14 hospital strains reported in the literature as nosocomial strains responsible for infections transmitted by flexible endoscopes and three vancomycin-resistant Enterococci. The ability of the seven automatic washer disinfectors to decontaminate flexible endoscopes following inoculation with four reference strains was studied with the second method. There were three kinds of results: the results of three automatic washer disinfectors in conformity with both methods; the results of three automatic washer disinfectors conformity with 1 method only; the results of one automatic washer disinfector without conformity with any methods. Both methods should be used for evaluation of automatic washer disinfector. Then, these results emphasize the necessity to modify the use of disinfectants and/or the systems of some automatic washer disinfectors.

[Validation of a sampling method for the channels of a flexible endoscope which is experimentally contaminated]. / Validation d'une méthode de prélèvement des canaux d'un endoscope souple contaminé expérimentalement.

The increase of endoscopic actions and infectious risks explains of interest in endoscopic material maintenance processing. This purpose study was to set to the point and validate a microbiological flexibles endoscopes channels (suction, biopsy, air/water) sample method. An inoculum made of faeces contents material and microorganisms suspension (Pseudomonas aeruginosa or Candida albicans), at low or high concentration, was injected into digestive endoscope's channels. For each microorganism, five trials were carried out at both of the two concentrations. After incubation, a global channels sample was performed with a recovering solution, then a counting was made. A variance analysis (ANOVA) concerning restated measures was performed for the whole results. The mean difference between the number of microorganisms injected and those recovered's is 0.114 log (IC95% [+0.088; +0.140]). It does not vary significantly according to the micro-organisms (p = 0.69) and the inoculum (p = 0.70). The coefficient of variation which is 0.525 (min: 0.010; max: 0.260) shows this method can be reproduced. This technique are allowed to be recommended to evaluate and to validate manuals and automatics endoscopes maintenance processing.