Endoscope drying/storage cabinet: interest and efficacy.

Inadequate drying of endoscope channels is a possible cause of microbial proliferation during storage. This risk could be reduced by any procedure or process used to dry endoscope channels and control storage conditions. The efficacy of a drying and storage cabinet (Hysis Medical) was tested on three different endoscopes: a colonoscope (Olympus); duodenoscope (Fujinon) and an enteroscope (Pentax), all of which had been artificially contaminated with a suspension of Pseudomonas aeruginosa CIP 103467. Changes to the residual internal contamination level of these endoscopes when stored inside or outside the drying cabinet for 12, 24, 48 or 72 h were compared. When stored in the drying and storage cabinet, microbial contamination levels on endoscopes were lower than the number of bacteria initially introduced and could decrease considerably thereafter. For endoscopes stored outside the drying storage cabinet, microbial numbers were stable or even increased. These data demonstrate the advantages of such endoscope drying/storage cabinets that limit the risk of bacterial proliferation in the internal channels of endoscopes during storage, and which ensure that the disinfection level reached at the end of the reprocessing procedure is maintained.

Evaluation of the microbicidal efficacy of Steris System I for digestive endoscopes using GERMANDE and ASTM validation protocols.

In the light of more and more invasive procedures being carried out in digestive endoscopy using sterile devices, it appears necessary to put in place a process of endoscope reprocessing capable of ensuring the complete elimination of micro-organisms contaminating the device. We undertook a study of the microbial efficacy of STERIS SYSTEM 1 (SS1) which purports to achieve this objective. The channels of a gastroscope and a colonoscope were contaminated with suspensions of Pseudomonas aeruginosa, Aspergillus niger and Bacillus subtilis spores. Two procedures were then followed: (1) manual washing only, and (2) treatment in SS1 without prewashing. Recoveries of organisms were made from each channel according to a standard methodology to discover any survivors. Contamination controls we re assessed to measure the logarithmic reduction between the initial contamination and that recovered from the channels. Six cycles per micro-organisms, per type of endoscope, and per type of procedure were carried out. From an initial contamination leve l of 10(6) micro-organisms per endoscope, no micro-organisms were recovered in 35 of the 36 cycles with the SS1. In one cycle with the colonoscope, three B. subtilis organisms were recovered from the channels. Washing only gave microbial reductions which varied according to the micro-organism tested. The maximum reduction with washing alone was by a factor of 10(3 +/- 0.1)for B. subtilis and the minimum reduction factor was 10(3 +/- 0.3)for P. aeruginosa. Considering the results obtained with SS1 without prewashing and the efficacy obtained from washing only, the washing step offers an additional antimicrobial assurance reduction factor of between 10 and 103.1. This study shows that SS1, integrated into an overall reprocessing procedure for digestive endoscopes, is capable of delivering the complete elimination of contaminating micro-organisms in a reduced time and eliminates the toxic risk of reprocessing associated with aldehyde based disinfectants.

[Bacterial contamination of multi-dose ocular solutions. A prospective study at the Grenoble Teaching Hospital]. / Contamination bactérienne des collyres multi-doses: étude prospective au CHU de Grenoble.

The bacterial contamination rate of multidose ocular solutions used by hospitalized patients was evaluated by culturing vial dropper tips and residual solution in vials. Bacterial colonies were counted and identified. Overall 39 (23.5%) selected vials were contaminated. Contamination rates were 17.7% (20/113) for vials used by ophthalmology ward patients and 35.8% (19/53) for vials used by internal medicine and gerontology patients (P < 0.02). The most commonly identified organisms were part of the normal commensal flora. Three ophthalmology patients were using vials contaminated with Pseudomonas aeruginosa. A significant (P < 0.01) positive correlation was found between vial contamination rate and duration of vial use. Vials containing an antimicrobial agent were less likely to be contaminated than vials without antimicrobials (P < 0.01). No clinical consequences of vial contamination were identified. However, ocular solution vial contamination carries a risk of infection. Our data are evidence of inadequate efficacy of preservatives present in ocular solutions. The standard practice of using ocular solution vials for seven days in health care facilities may need to be reappraised. Care should be taken to ensure that health care providers and patients understand the rules for ocular solution use. Unit-dose presentations may be preferable over multi-dose presentations for in hospital treatment.

[Virus resistance in a hospital environment: overview of the virucide activity of disinfectants used in liquid form]. / Résistance des virus dans l'environnement hospitalier: le point sur l'activité virucide des désinfectants utilisés à l'état liquide.

Human pathogenic viruses can be detected in the hospital environment, on contaminated surfaces or medical instruments. Their transmission to patients or staff has already been reported. Lipophilic viruses (HIV, HBV, HCV,...) are susceptible to many liquid chemicals, but they can survive during short time on inadequately disinfected surfaces. Hydrophilic viruses, without envelope, are more resistant, but generally not associated with severe illnesses. Viruses survival in environment depends on many factors and is always improved with viral aggregation and low temperature, whereas organic matters and relative humidity effects are contrasted. The mechanism of virucide disinfectants is not yet well established, and their targets are not known with precision. Different disinfection procedures (disinfectant concentration, contact time, temperature, pH) can provide a similar virucidal activity on a given virus. The virucidal activity of a disinfectant is evaluated with a cell culture assay in Afnor guidelines. But, there are three major problems with this method, concerning need of high viruses titers, residual disinfectant cytotoxicity on cell culture, and non cultivable viruses. Non standardized tests are also described in papers, but their results can generally not be compared. Molecular biology improvements may lead to reproducible and sensitive tests. At present, no general disinfection procedure effective for most of the viruses, without risks for staff or materials, and with an acceptable economic cost can be recommended.