Efficacy of electrolyzed acid water in reprocessing patient-used flexible upper endoscopes: Comparison with 2% alkaline glutaraldehyde

BACKGROUND AND AIM: Two percent glutaraldehyde, the most widely used liquid chemical germicide (LCG), may be hazardous to patients and medical personnel. Alternatives to glutaraldehyde, such as electrolyzed acid water (EAW), are being developed, but data from well-controlled studies with patient-used endoscopes are rare. The purpose of the present paper was to evaluate the high-level disinfection capability of EAW and compare it with glutaraldehyde. METHODS: A random sample of 125 endoscopes was collected immediately after upper endoscopic examination. After careful manual cleaning, endoscopes were divided into a glutaraldehyde and EAW group. After the disinfection procedure, samples from working channel (S-1), insertion tube (S-2), umbilical cord (S-3), and angulation knob (S-4) were taken and cultured. Another twenty endoscopes were experimentally contaminated with hepatitis B virus (HBV) and samples were collected after contamination (T-1), after manual cleaning (T-2), and after final disinfection (T-3). Polymerase chain reaction (PCR) for HBV-DNA was performed. RESULTS: In the EAW group, culture-positive rates were 3.2% in S-1, 9.5% in S-2, 3.2% in S-3, and 27.0% in the S-4 samples. There was no significant difference between the EAW and glutaraldehyde groups for all sampling sites. However, in both groups, disinfection of the angulation knobs (S-4) was less efficient than the others. For the T-1 site, HBV-DNA was detected from all of them, and in 95% (19/20) of T-2. However, HBV-DNA was not detected from T-3 samples. CONCLUSIONS: Electrolyzed acid water is as efficient as glutaraldehyde in eliminating bacteria from patient-used endoscopes. After disinfection procedures using both methods, HBV-DNA was not detected from any endoscopes experimentally contaminated with HBV-positive mixed sera. However, some bacteria may remain on the surface of the endoscopes. Therefore, more careful precleaning of the endoscopes may help achieve high-level disinfection in the clinical setting.     

Guidelines for standardizing cleansing and disinfection of gastrointestinal endoscopes

As part of the activities toward standardizing endoscopy procedures, the Japan Gastroenterological Endoscopy Society has prepared guidelines for cleansing and disinfection of gastrointestinal endoscopes. The environment of gastrointestinal endoscopy differs between Japan and advanced Western countries. In advanced Western countries, gastrointestinal endoscopy is performed almost exclusively at specialized facilities, where strict provisions are observed for cleansing and disinfecting endoscopes. In Japan, however, gastrointestinal endoscopy is performed even in small clinics, and the annual number of gastrointestinal endoscopy cases is enormous. In addition, the method for cleansing and disinfecting endoscopes differs among hospitals. Although there is a distinct lack of evidence for how gastrointestinal endoscopes are cleaned and disinfected, it is necessary to standardize the method for doing so to advance the field of endoscopic medicine.     

Bacteriologic testing of endoscopes after high-level disinfection

BACKGROUND: There are no definitive data available concerning microbiologic safety of prolonged endoscope storage after reprocessing and disinfection. This study evaluated the durability of high-level disinfection of endoscopes stored in a dust-proof cabinet for 5 days. METHODS: Three different types of endoscopes (upper endoscopes, duodenoscopes, colonoscopes) were tested. After completion of the endoscopic procedure, endoscopes were subjected to an initial decontamination, followed by manual cleaning with the endoscope immersed in detergent. The endoscopes then were placed in an automatic reprocessor that provides high-level disinfection. They then were stored by hanging in a dust-proof cabinet. Bacteriologic samples were obtained from the surface of the endoscopes, the openings for the piston valves, and the accessory channel daily for 5 days, and by flush-through (combined with brushing) from the accessory channels after 5 days of storage. Samples were cultured for all types of aerobic and anaerobic bacteria, including bacterial spores, and for Candida species. RESULTS: For all assays, all endoscopes were bacteria-free immediately after high-level disinfection. Only 4 assays (of 135) were positive during the subsequent 5-day assessment (skin bacteria cultured from endoscope surfaces). All flush-through samples were sterile. CONCLUSIONS: When endoscope reprocessing guidelines are strictly observed and endoscopes are stored in appropriate cabinets for up to 5 days, reprocessing before use may not be necessary.     

Disinfection of endoscopes from Helicobacter pylori-positive subjects: evaluation of the effectiveness of the Chinese Calijing disinfection kit

BACKGROUND: The aim of this study was to evaluate the effectiveness of the Calijing disinfection kit (an endoscope disinfection method used in Chinese hospitals) in eradicating Helicobacter pylori and assess whether use of the kit in 1994 during endoscopies in the Shandong Intervention Trial (SIT), Shandong, China, could have resulted in iatrogenic transmission of H pylori . METHODS: Bacterial culture studies at the Veterans Affairs Medical Center, Houston, Texas, using endoscopes and forceps from 49 H pylori -positive patients were performed on contaminated endoscopes before and after disinfection with the Calijing kit. RESULTS: At least 1 endoscope culture site was H pylori positive in 39 of 49 (79.6%) specimens predisinfection, whereas H pylori was not isolated from any endoscopic culture site postdisinfection. Non- H pylori bacteria and fungi were recovered from 22.6% of the postdisinfection cultures. CONCLUSION: Although no viable H pylori were recovered following the disinfection procedures, levels of H pylori below the detection threshold of the bacteriologic assay may have contributed to an increase in H pylori seroprevalence noted in the SIT. In addition, the kit was unable to provide disinfection against non- H pylori organisms, suggesting the need to adhere to internationally accepted disinfection procedures for endoscope reprocessing.     

Multi-state investigation of the actual disinfection/sterilization of endoscopes in health care facilities.

PURPOSE: The purpose of this investigation was to observe and assess the actual disinfection or sterilization of endoscopes in health care facilities. MATERIALS AND METHODS: A total of 22 hospitals and four ambulatory care centers in three states were studied. Facility protocols were reviewed, interviews conducted with relevant personnel, actual disinfection or sterilization procedures observed, and biologic tests performed to determine and assess disinfection/sterilization procedures. RESULTS: Fundamental errors observed during the course of the investigation included respective failures to time the period of disinfection, to clean all channels, to flush all channels with disinfectant, to fully immerse the endoscope in the disinfectant solution, and to use a disinfectant. At 78% of the facilities, failure to sterilize all biopsy forceps was observed. A total of 23.9% of the bacterial cultures from the internal channels of 71 gastrointestinal endoscopes grew 100,000 colonies or more of bacteria. These cultures were obtained after the completion of all disinfection/sterilization procedures and the device was deemed ready for use in the next patient. CONCLUSIONS: These data indicate that actual disinfection/sterilization procedures for endoscopes are not always optimal, and high-level disinfection of gastrointestinal endoscopes is not always achieved.     

Reprocessing of flexible endoscopes and endoscopic accessories - an international comparison of guidelines

Endoscopic examinations and procedures are essential for diagnosis and treatment of gastrointestinal diseases. As a result of poor reprocessing practice microorganisms can be transmitted via endoscope. The majority of infection transmissions is due to insufficient performance of cleaning and disinfection disregarding guidelines of societies of gastrointestinal endoscopy. A review of the literature and a comparison of European and American guidelines for reprocessing flexible endoscopes are given. Differences in the classification of endoscopic devices, on the possibility of prion transmission, recommendations on staff training and protection, quality assurance of reprocessing and evidence-based graduation of guidelines are stressed and discussed. With respect to the procedure of endoscope reprocessing, differences concerning the cleaning solution to choose, necessity of thoroughly manual cleaning and brushing of the accessible endoscope channels (even in the case of subsequent automatic reprocessing endoscopes in washers-disinfectors), disinfection solution, microbiological quality of water for final rinsing and rationale for alcohol flush of endoscope channels for better drying are mentioned. The need for experimental investigations of the cleaning and disinfection process is stressed. In contrast to recent guidelines of European and American societies of gastrointestinal endoscopy, the now updated recommendations of the Robert Koch-Institute for reprocessing flexible endoscopes and endoscopic accessories are evidence-based and graduated.     

The clinical risks of infection associated with endoscopy.

The cleaning of flexible endoscopes is difficult and time consuming. Any method of attempted sterilization or high level disinfection will fail if prior cleaning has been defective. Inadequate reprocessing of endoscopes may result in patient to patient transmission of serious bacterial and viral diseases or infection with endemic hospital pathogens. Antibiotic prophylaxis is required to prevent septicemia and bacterial endocarditis in high risk patients undergoing specific endoscopic procedures. Prevention of serious endoscopy-associated clinical infections requires strict compliance with detailed reprocessing protocols by specially trained nursing staff.     

Cleaning and disinfection of equipment for gastrointestinal flexible endoscopy: interim recommendations of a Working Party of the British Society of Gastroenterology.

1. All patients undergoing gastrointestinal endoscopy must be considered 'at risk' for HIV and appropriate cleaning/disinfection measures taken for endoscopes and accessories. 2. Thorough manual cleaning with detergent, of the instrument and its channels is the most important part of the cleaning/disinfection procedure. Without this, blood, mucus and organic material will prevent adequate penetration of disinfectant for inactivation of bacteria and viruses. 3. Aldehyde preparations (2% activated glutaraldehyde and related products) are the recommended first line antibacterial and antiviral disinfectant. A four minute soak is recommended as sufficient for inactivation of vegetative bacteria and viruses (including HIV and HBV). 4. Quaternary ammonium detergents (8% Dettox for two minutes for bacterial disinfection), followed by exposure of the endoscope shaft and channels to ethyl alcohol (70% for four minutes for viral inactivation), is an acceptable second-line disinfectant routine where staff sensitisation prevents the use of an aldehyde disinfectant. 5. Accessories, including mouthguards and cleaning brushes, require similarly careful cleaning/disinfection, before and after each use. Disposable products (especially injection needles) may be used and appropriate items can be sterilised by autoclaving and kept in sterile packs. 6. Closed circuit endoscope washing machines have advantages in maintaining standards and avoiding staff sensitisation to disinfectants. Improved ventilation including exhaust extraction facilities may be required. 7. Endoscopy staff should receive HBV vaccination, wear gloves and appropriate protective garments, cover wounds or abrasions and avoid needlestick injuries (including spiked forceps, etc). 8. Known HIV-infected or AIDS patients are managed as immunosuppressed, and require protection from atypical mycobacteria/cryptosporidia etc, by one hour aldehyde disinfection of endoscopic equipment before and after the procedure. A dedicated instrument is not required. 9. Increased funding is necessary for capital purchases of GI endoscopic equipment, including extra and immersible endoscopes with additional accessories to allow for safe practice. 10. Greater numbers of trained GI assistants are needed to ensure that cleaning/disinfection recommendations and safety precautions are followed, both during routine lists and emergency endoscopic procedures. 11. These recommendations are based on expert interpretation of current data on infectivity and disinfection; they may require future modification.     

Cleaning and disinfection of gastrointestinal endoscopes. Comparative analysis of two disinfectants.

Gastrointestinal endoscopy can lead to infectious complications, and endoscopes must be disinfected to prevent them. AIM: to evaluate three methods of disinfection: 1) usual cleaning technique and immersion in glutaraldehyde phenolate (GP); 2) meticulous cleaning and immersion in GP, and 3) meticulous cleaning and immersion in hydrogen peroxide. METHOD: thirty endoscopes (15 gastroscopes and 15 colonoscopes) were disinfected with each method. Samples were taken following endoscopic exploration, after cleaning and after disinfection, and were cultured. The number of positive culture (cfu/ml > 1) was counted. RESULTS: the rate of contamination of endoscopes did not decrease significantly after cleaning with method 1 (66 vs 60%), but did decrease with method 2 (38 vs 16%) and method 3 (53 vs 17%). The contamination rate after cleaning was significantly lower with methods 2 and 3 (p < 0.005). This rate was also lower after disinfection (p < 0.025). Method 3 achieved 0% contamination following disinfection. CONCLUSIONS: the greatest decrease in contamination rate was achieved with conscientious cleaning followed by disinfection. Both disinfectants yielded similar results, although hydrogen peroxide produced a higher level of disinfection.     

Microbiological monitoring of endoscopes: 5-year review

Periodic microbiological monitoring of endoscopes is a recommendation of the Gastroenterological Society of Australia (GENSA). The aim of monitoring has been to provide quality assurance of the cleaning and disinfection of endoscopes; however, there is controversy regarding its frequency. This lack of consensus stimulated a review of the experience within our health service. At Southern Health, routine microbiological sampling has involved 4-weekly monitoring of bronchoscopes, duodenoscopes and automated flexible endoscope reprocessors (AFER), and 3-monthly monitoring of all other gastrointestinal endoscopes. Records of testing were reviewed from 1 January 2002 until 31 December 2006. A literature review was conducted, cost analysis performed and positive cultures investigated. There were 2374 screening tests performed during the 5-year period, including 287 AFER, 631 bronchoscopes for mycobacteria and 1456 endoscope bacterial screens. There were no positive results of the AFER or bronchoscopes for mycobacteria. Of the 1456 endoscopic bacterial samples, six were positive; however, retesting resulted in no growth. The overall cost of tests performed and cost in time for nursing staff to collect the samples was estimated at $AUD 100 400. Periodic monitoring of endoscopes is both time-consuming and costly. Our review demonstrates that AFER (Soluscope) perform well in cleaning endoscopes. Based on our 5-year experience, assurance of quality for endoscopic use could be achieved through process control as opposed to product control. Maintenance of endoscopes and AFER should be in accordance with the manufacturer's instructions and microbiological testing performed on commissioning, annually and following repair. Initial prompt manual leak testing and manual cleaning followed by mechanical leak testing, cleaning and disinfection should be the minimum standard in reprocessing of endoscopes.     

Hygienic measures in endoscopy

Risks of infection associated with endoscopy, sources of infection, relevant microorganisms (P. aeruginosa, Serratia, HIV, HB, Cryptosporidiosis), disinfection procedures and the steps of disinfection procedures and reasons for failing of disinfection procedures are discussed. Channel systems and rinsing solutions are relevant but until today underestimated sources of infection. In detail the contamination of the channel system in endoscopes, problems of good disinfection and the significance of mechanical cleaning are described. In cases of Pseudomonas aeruginosa infections after endoscopy an immediate investigation of the contamination of the endoscope and of rinsing solutions is necessary. Automatic disinfection systems are requested, because with such systems a higher security for patient and personal is achievable. A regular control of the efficacy of the disinfection process by a competent Hygiene-Institute is recommended.     

Microbiologic profile of flexible endoscope disinfection in two Brazilian hospitals

BACKGROUND: [corrected] Endoscopes are routinely used in hospitals and clinics of the world and they can be potential sources of cross-infection when the decontamination process is unsuitable AIM: The routines of flexible endoscope (bronchoscopes, esophagogastroduodenoscopes and colonoscopes) disinfection procedures used in two Brazilian university hospitals were evaluated during a 3-year period METHODS: Aleatory samples from internal channels of endoscopes were collected after patient examination and after cleaning/disinfection procedures RESULTS: A contamination >3 log10 was achieved in samples recovered from endoscopes after patient examination. These samples yielded gram-negative bacilli (n = 142: 56%), gram-positive cocci (n = 43: 17%), yeast cells (n = 43: 17%), and gram-positive bacilli (n = 26: 10%). Approximately, 72 out of 149 samples (48.32%) collected after undergoing the cleaning and disinfection procedures disclosed gram-negative bacilli (n = 55: 61%), gram-positive cocci (n = 21: 23%), gram-positive bacilli (n = 8: 9%) and yeast cells (n = 6: 7%). Esophagogastroduodenoscopes and colonoscopes were the most frequently contaminated devices. Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Enterobacter spp, Serratia marcescens, Proteus mirabilis, Citrobacter freundii, Staphylococcus aureus, Staphylococcus coagulase negative, Micrococcus luteus, Candida albicans, C. tropicalis, C. glabrata, C. guilliermondii, Bacillus spp and Corynebacterium spp were predominantly identified CONCLUSION: Inappropriate cleaning and low times of disinfection were respectively the major factors associated with the presence of microorganisms in colonoscopes and esophagogastroduodenoscopes. By analyzing the identified germs, hospital disinfection was considered of either intermediate or poor level. After this investigation, both university centers improved their previous protocols for disinfection and conditions for reprocessing endoscopes.     

GI endoscopic reprocessing practices in the United States.

BACKGROUND: Patient infection from contaminated gastrointestinal (GI) endoscopes can generally be attributed to failure to follow appropriate reprocessing guidelines. Recently, the Food and Drug Administration recommended a 45-minute exposure of GI endoscopes to 2.4% glutaraldehyde solutions heated to 25 degrees C. Simultaneously, the American Society for Gastrointestinal Endoscopy (ASGE), the American Gastroenterological Association, and the Society of Gastroenterology Nurses and Associates endorsed a reprocessing guideline that emphasized manual precleaning and recommended a 20-minute exposure to a 2.4% glutaraldehyde solution at room temperature. Since then, little information has become available regarding actual reprocessing practices in the United States. METHODS: A previously developed questionnaire regarding endoscopic disinfection practices was mailed to randomly selected members of the ASGE. RESULTS: The survey was sent to 730 members and 294 responded (40.3%). Appropriate manual cleaning (suctioning detergent through the accessory channel and brushing the channel and valves) is performed by 90.7% of respondents; 69.9% then use automated reprocessors for disinfection or sterilization. Glutaraldehyde is the most widely used chemical disinfectant; 85.3% use glutaraldehyde as one of their primary disinfectants. The most commonly used disinfection time with 2.4% glutaraldehyde is 20 minutes (83.9%) followed by 45 minutes (11.4%). Only 23.8% of users of 2.4% glutaraldehyde heat their solution; 59.6% of centers test disinfectant concentration daily or more frequently; 74.0% sterilize nondisposable forceps before use; 29.2% of centers re-use disposable endoscopic accessories (which are more frequently disinfected rather than sterilized). Twelve respondents reported cases of endoscopic cross infection. CONCLUSIONS: A significant minority of endoscopy centers still do not completely conform to recent ASGE, American Gastroenterological Association, and the Society of Gastroenterology Nurses and Associates guidelines on disinfection, and they may not be appropriately disinfecting GI endoscopes. Rigid adherence to recommended guidelines is strongly encouraged to ensure patient safety.     

Antimicrobial efficacy of endoscopic disinfection procedures: a controlled, multifactorial investigation.

BACKGROUND: Adequate disinfection of endoscopes is essential to prevent environmental and patient-to-patient transmission of infectious agents, but data from controlled studies are limited. Moreover, there is controversy regarding current guidelines for disinfection. We compared the antimicrobial efficacy of several endoscopic disinfection procedures controlling for multiple factors that affect reprocessing. METHODS: A colonoscope was contaminated with 10(8) CFU/mL of Enterococcus faecalis as a standardized inoculum. The colonoscope was passed through 1 of 16 study arms (5 reps/arm for a total of 80 runs) that were controlled for all possible combinations of the following variables: manual precleaning; 10-, 20-, or 45-minute glutaraldehyde exposure; air or ethanol drying; or automated reprocessing with peracetic acid (liquid sterilization system). Suction accessory channels and air-water channels were harvested for microbiologic culture. RESULTS: Control runs (no cleaning or disinfection) recovered more than 5 x 10(7) CFU/mL from each sampling site. When each processing variable was isolated independent of other variables, the benefits of manual precleaning, longer soak times, and ethanol drying were apparent. When factors were combined, manual precleaning followed by 20- and 45-minute glutaraldehyde exposure and ethanol drying removed all test organisms, as did processing with the liquid sterilization system. CONCLUSION: Although the initial cost is higher, the automated liquid sterilization system provides effective sterilization and minimizes worker exposure. In units where chemical disinfection is used, our results suggest that manual precleaning followed by at least 20-minute glutaraldehyde exposure and ethanol rinse drying are sufficient to achieve complete disinfection.     

Efficacy of routine fiberoptic endoscope cleaning and disinfection for killing Clostridium difficile

We have evaluated a standard procedure for cleaning and disinfection of endoscopes for efficacy in eradicating a spore-forming bacterial organism, Clostridium difficile. Initially, 23 endoscopes were cultured for the presence of C. difficile after hanging in storage for at least 24 hours after cleaning and disinfection. All cultures were negative. Subsequently, endoscopes used in 15 patients who had stool cultures positive for C. difficile were cultured immediately after use and again after cleaning and disinfection with 2% alkaline glutaraldehyde for 5 min. Ten of 15 (67%) endoscopes were culture positive for C. difficile immediately after use. After cleaning and disinfection, all of the endoscopes were culture negative except one, which yielded two negative cultures and two cultures showing late growth of rare C. difficile colonies, but contamination could not be ruled out. In vitro exposure to 2% alkaline glutaraldehyde for 5 min resulted in 99% or greater killing of C. difficile spores. We conclude that cleaning and a minimum of 5 min of disinfection with 2% alkaline glutaraldehyde are likely to be effective in killing C. difficile vegetative organisms and spores on endoscopes.     

HYGEA (Hygiene in gastroenterology--endoscope reprocessing): Study on quality of reprocessing flexible endoscopes in hospitals and in the practice setting

The quality of reprocessing gastroscopes, colonoscopes and duodenoscopes in daily routine of 25 endoscopy departments in hospitals and 30 doctors with their own practices was evaluated by microbiological testing in the HYGEA interventional study.In 2 test periods, endoscopes ready for use in patients were found contaminated at high rates (period 1: 49 % of 152 endoscopes; period 2: 39 % of 154 endoscopes). Culture of bacterial fecal flora (E. coli, coliform enterobacteriaceae, enterococci) was interpreted indicating failure of cleaning procedure and disinfection of endoscopes. Detection of Pseudomonas spp. (especially P. aeruginosa) and other non-fermenting rods - indicating microbially insufficient final rinsing and incomplete drying of the endoscope or a contaminated flushing equipment for the air/water-channel - pointed out endoscope recontamination during reprocessing or afterwards. Cause for complaint was found in more than 50 % of endoscopy facilities tested (period 2: 5 in hospitals, 25 practices). Reprocessing endoscopes in fully automatic chemo-thermally decontaminating washer-disinfectors with disinfection of final rinsing water led to much better results than manual or semi-automatic procedures (failure rate of endoscopy facilities in period 2 : 3 of 28 with fully automatic, 8 of 12 with manual, 9 of 15 with semi-automatic reprocessing). The study results give evidence for the following recommendations: 1. Manual brushing of all accessible endoscope channels has to be performed even before further automatic reprocessing; 2. For final endoscope rinsing, water or aqua dest. should only be used disinfected or sterile-filtered; 3. Endoscopes have to be dried thoroughly using compressed air prior to storage; 4. Bottle and tube for air/water-channel flushing have to be reprocessed daily by disinfection or sterilization, and in use, the bottle have to be filled exclusively with sterile water.The HYGEA study shows that microbiological testing of endoscopes is useful for detection of insufficient reprocessing and should be performed for quality assurance in doctors' practices, too. The study put recommendations for reprocessing procedures in more concrete terms.     

Disinfection of gastrointestinal endoscopes and accessories

Abstract A worldwide concern has emerged with regard to endoscope disinfection and many gastrointestinal endoscopy associations have developed guidelines for proper disinfection of endoscopes and endoscopic accessories. A working party was convened to formulate guidelines for the Asia–Pacific region, pertaining to any setting in which gastrointestinal endoscopy is performed. Endoscope reprocessing that meets the established standard of practice helps to ensure a microbial-free endoscope for all patients, reduces the risk of disease transmission and helps to prolong the life of the endoscope. The recommendations included mechanical cleaning as the first and most important step followed by immersion in 2% glutaraldehyde for a minimum period of 10 min. Automated disinfectors have been recommended for busy endoscopy centres to ensure better compliance. Reuse of endoscopic accessories meant for 'single use' remains a controversial issue. Strict quality assurance programmes are a must to preclude lack of compliance with these guidelines.     

Surveillance cultures to monitor quality of gastrointestinal endoscope reprocessing

OBJECTIVES: High-level disinfection of GI endoscopes can be reliably obtained under controlled conditions with approved reprocessing methods. However, there are scant data regarding the effectiveness of these methods in clinical practice and no published methods of verification. The purpose of this study is to review retrospectively the results of environmental cultures of flexible endoscopes and to analyze the pattern of results. METHODS: Cultures of selected GI endoscopes listed as ready to use were obtained by adding 5-15 ml of trypticase soy broth or saline or 30-50 ml of sterile water to the biopsy channel of an endoscope. This wash was collected in a sterile container, plated onto blood and MacConkey agar, incubated at 37 degrees C, and examined for growth at 24 and 48 h. Personnel trained in accordance with approved procedures performed endoscope reprocessing. RESULTS: A total of 312 surveillance cultures were performed between 1990 and 1999. Initially, three of 17 water bottles were found to be contaminated with Pseudomonas species. The bottles were sterilized daily; only sterile water was used and subsequent cultures were negative. Between 1992 and 1994, 15/129 (11.6%) cultures were positive; 14 (93%) were from duodenoscopes. From 1995 to 1997, 18/124 (14.5%) cultures were positive, but only six (33%) were from duodenoscopes. However, 10 (55.6%) positive cultures were obtained from therapeutic upper endoscopes, attributed to faulty mechanical cleaning by nonnursing personnel after emergent procedures. The reprocessing procedure was altered, with improvement. One duodenoscope was persistently culture positive and was found to have a damaged biopsy channel. There were no recognized iatrogenic infections associated with endoscopic procedures. Organisms cultured were commonly gram-negative rods. CONCLUSIONS: The use of environmental endoscope culturing is a rapid, simple, inexpensive method to monitor effectiveness of standard reprocessing procedures. Disinfection is less effective with poor mechanical cleansing, and high-titer positivity is a marker for poor cleaning technique. Standard upper and lower scopes are commonly culture negative. Duodenoscopes, because of their inherent complexity, and other scopes used in emergent conditions require particular attention. Surveillance culture results can be used to identify patterns of poor technique, to reinforce proper procedure, and to modify clinical practice. No associated clinical illness was apparent during this study.     

Preventing nosocomial infections from gastrointestinal endoscopy

Gastrointestinal procedures have been associated with a wide range of infectious complications, including bacterial endocarditis. Although the rate of bacteremia from the patient's own flora is quite high after some procedures, only a few cases of endocarditis caused by gastrointestinal instrumentation have been reported. Because of the severity of the illness, however, antibiotic prophylaxis has been recommended for patients who are categorized as high risk for some procedures. Bacteremia and other infections, such as colitis, may also originate from a contaminated endoscope. To prevent such an occurrence, high-level disinfection has been recommended for gastrointestinal endoscopes. High-level disinfection includes manual cleaning of the endoscope, flushing of internal channels with a liquid chemical sterilant, and thorough rinsing and drying of internal lumens.     

Computer-aided recording of automatic endoscope washing and disinfection processes as an integral part of medical documentation for quality assurance purposes

Background  

The reprocessing of medical endoscopes is carried out using automatic cleaning and disinfection machines. The documentation and archiving of records of properly conducted reprocessing procedures is the last and increasingly important part of the reprocessing cycle for flexible endoscopes.