Evaluation of 12-Week Shelf Life of Patient-Ready Endoscopes.

Current research suggests that for certain types of gastrointestinal endoscopes, longer shelf life (the interval of storage after which endoscopes should be reprocessed before their reuse) may not increase the likelihood of endoscope contamination. Scope contamination may, in fact, be related primarily to either inadequate disinfection processes or inadvertent contamination during storage, not to duration of storage. The purpose of this study evaluated the presence of bacteria and fungus following liquid chemical sterilization in colonoscopes and gastroscopes, after 12 weeks of shelf life during which time personal protective equipment was used during endoscope storage cabinet access. We stored four colonoscopes and two gastroscopes in a cabinet for 12 weeks after liquid chemical sterilization and the cabinet was only accessed during the 12-week period wearing personal protective equipment (gown and gloves). Scopes were tested for bacteria and fungus at the end of 12 weeks. No bacteria or fungus grew on any of the scopes. This study provides further support that contaminated endoscopes may be related to either inadequate disinfection or contamination during storage, not shelf life.

Potential testing of reprocessing procedures by real-time polymerase chain reaction: A multicenter study of colonoscopy devices.

BACKGROUND: Reprocessing of endoscopes is key to preventing cross-infection after colonoscopy. Culture-based methods are recommended for monitoring, but alternative and rapid approaches are needed to improve surveillance and reduce turnover times. A molecular strategy based on detection of residual traces from gut microbiota was developed and tested using a multicenter survey. METHODS: A simplified sampling and DNA extraction protocol using nylon-tipped flocked swabs was optimized. A multiplex real-time polymerase chain reaction (PCR) test was developed that targeted 6 bacteria genes that were amplified in 3 mixes. The method was validated by interlaboratory tests involving 5 reference laboratories. Colonoscopy devices (n = 111) were sampled in 10 Italian hospitals. Culture-based microbiology and metagenomic tests were performed to verify PCR data. RESULTS: The sampling method was easily applied in all 10 endoscopy units and the optimized DNA extraction and amplification protocol was successfully performed by all of the involved laboratories. This PCR-based method allowed identification of both contaminated (n = 59) and fully reprocessed endoscopes (n = 52) with high sensibility (98%) and specificity (98%), within 3-4 hours, in contrast to the 24-72 hours needed for a classic microbiology test. Results were confirmed by next-generation sequencing and classic microbiology. CONCLUSIONS: A novel approach for monitoring reprocessing of colonoscopy devices was developed and successfully applied in a multicenter survey. The general principle of tracing biological fluids through microflora DNA amplification was successfully applied and may represent a promising approach for hospital hygiene.

Assessing residual contamination and damage inside flexible endoscopes over time.

Researchers evaluated flexible endoscope damage and contamination levels at baseline and 2 months later. Postcleaning test results exceeded benchmarks for all gastroscopes and no colonoscopes. Microbial growth was found in samples from 47% of fully reprocessed endoscopes at baseline and 60% at follow-up. Borescope examinations identified scratches, discoloration, debris, and fluid inside endoscopes. Irregularities changed over time. Study evaluations allowed damaged and contaminated endoscopes to be identified and re-reprocessed or sent for repairs.

Trends in quality of screening colonoscopy in Austria.

Background and study aim: Screening colonoscopy only effectively prevents colorectal cancer if performed with high quality. The aim of this study was to analyze the detection rates of premalignant colorectal lesions in screening colonoscopies performed within a nationwide quality control program for screening colonoscopy in Austria. Methods: Data from electronic records of the screening program from its implementation in 2007 until December 2014 were analyzed in order to calculate detection rates for adenomas, advanced adenomas, polyps, and proximal lesions, and rates of cecal intubation, sedation, complications, and adequate bowel preparation. Results were evaluated to identify trends and changes in quality parameters over the 8-year study period. Results: During the study period, 301 endoscopists provided data from 159 246 screening colonoscopies. Mean age of screened individuals was 61.1 years, and 49.1 % were women. Significant increases over time were found for age- and sex-adjusted adenoma detection rates (ADRs), which increased from a mean of 22.2 % (SD 10.7 %) in 2007/2008 to 24.2 % (SD 11.6 %) in 2013/2014. On average, each endoscopist increased their individual ADR by + 1.5 percentage points per 2-year period (95 % confidence interval [CI] 0.9 - 2.2 percentage points; P < 0.01). Similarly, detection rates for proximal lesions rose from 15.8 % (SD 9.8 %) to 21.7 % (SD 13.3 %  + 2.5 percentage points per 2-year period, 95 %CI 1.9 - 3.1 percentage points; P < 0.01). ADR in men increased from 27.6 % in 2007/2008 (SD 11.1 %) to 29.2 % in 2013/2014 (SD 12.7 %; P < 0.01); ADR in women increased from 14.2 % (SD 7.1 %) in 2007/2008 to 19.0 % (SD 10.5 %) in 2013/2014 (P < 0.01). Advanced adenoma detection rates decreased during the study period, from 11.4 % (SD 9.0 %) in 2007/2008 to 7.6 % (SD 5.4 %) in 2013/2014 (P = 0.06) in men, and from 5.5 % (SD 5.3 %) in 2007/2008 to 4.0 % (SD 4.1 %) in 2013/2014 in women (P = 0.21). Conclusions: This study showed an improvement in the quality of screening colonoscopies performed within a quality assurance program in Austria between 2007 and 2014. Although, overall ADR increased significantly during the study period, there was a decrease in the rate of advanced adenoma detection.

Practical toolkit for monitoring endoscope reprocessing effectiveness: Identification of viable bacteria on gastroscopes, colonoscopes, and bronchoscopes.

BACKGROUND: Experts have recommended microbiologic surveillance by external reference laboratories for certain flexible endoscopes. There is currently insufficient evidence on the feasibility and utility of cultures. Researchers evaluated a preassembled toolkit for collecting and processing samples from endoscopes. METHODS: A pilot study was performed in a large academic medical center. A toolkit was used to aseptically sample biopsy ports and suction/biopsy channels of 5 gastroscopes, 5 colonoscopes, and 5 bronchoscopes after full reprocessing. Blinded specimens were packaged and transported on icepacks to a reference laboratory that used standard methodologies for microbial cultures. RESULTS: The laboratory detected bacteria in samples from 60% of patient-ready endoscopes, including gram-positive and gram-negative species. Viable microbes (<10 CFU) were recovered from 2 gastroscopes, 3 colonoscopes, and 4 bronchoscopes. Stenotrophomonas maltophilia and Delftia acidovorans were recovered from all 3 endoscope types. Subsequent environmental testing detected S maltophilia in the reprocessing rinse water. CONCLUSIONS: A preassembled toolkit facilitated the aseptic collection of samples for culturing by a reference laboratory that detected viable microbes on fully reprocessed endoscopes. Speciation allowed identification of potential pathogens and a possible common contamination source, demonstrating that microbial cultures may have value even when colony counts are low.

Persistent contamination on colonoscopes and gastroscopes detected by biologic cultures and rapid indicators despite reprocessing performed in accordance with guidelines.

BACKGROUND: Pathogens have been transmitted via flexible endoscopes that were reportedly reprocessed in accordance with guidelines. METHODS: Researchers observed reprocessing activities to ensure guideline compliance in a large gastrointestinal endoscopy unit. Contamination was assessed immediately after bedside cleaning, manual cleaning, high-level disinfection, and overnight storage via visual inspection, aerobic cultures, and tests for adenosine triphosphate (ATP), protein, carbohydrate, and hemoglobin. RESULTS: All colonoscopes and gastroscopes were reprocessed in accordance with guidelines during the study. Researchers collected and tested samples during 60 encounters with 15 endoscopes. Viable microbes were recovered from bedside-cleaned (92%), manually cleaned (46%), high-level disinfected (64%), and stored (9%) endoscopes. Rapid indicator tests detected contamination (protein, carbohydrate, hemoglobin, or ATP) above benchmarks on bedside-cleaned (100%), manually cleaned (92%), high-level disinfected (73%), and stored (82%) endoscopes. Visible residue was never observed on endoscopes, but it was often seen on materials used to sample endoscopes. Seven endoscopes underwent additional reprocessing in response to positive rapid indicators. Control endoscope channels were free of biologic residue and viable microbes. CONCLUSION: Despite reprocessing in accordance with US guidelines, viable microbes and biologic debris persisted on clinically used gastrointestinal endoscopes, suggesting current reprocessing guidelines are not sufficient to ensure successful decontamination.

Evaluation of medically significant bacteria in colonoscopes after 8 weeks of shelf life in open air storage.

The purpose of this study was to examine bacterial growth in colonoscopes in a series of graduated shelf times. There is no conclusive evidence on the length of time colonoscopes can be safely stored before requiring redisinfection. Standards for processing scopes after use are described and supported by the professional organizations of gastroenterology and infection control; however, shelf life varies from 3 to 5 days and most recommendations are based on clinical consensus. In this study, four colonoscopes were used in a clinical procedure, underwent automated high-level disinfection with 2.6% buffered glutaraldehyde, and cultured after 3, 5, 7, 14, 21, 28, 42, and 56 days of shelf time. Two investigators collected all the cultures after interrater reliability was established. Cultures were processed in the microbiology laboratory. No medically significant growth was detected at any of the culture points. At Day 14 and Day 42, one of four scopes grew fewer than two colony-forming units of a medically insignificant bacterium. Using professional standards for high-level disinfection growth was suppressed for up to 8 weeks. Further evidence to assess fungal or viral growth is needed to be able to make suggestions for colonoscope shelf life.

Effectiveness of flexible gastrointestinal endoscope reprocessing.

The practice of reprocessing endoscopes and its effectiveness was evaluated in 37 services. Contamination of at least 1 endoscope could be identified in 34 (91.6%) of 37 services. Bacteria, fungi, and/or mycobacteria were isolated from 84.6% (33/39) of the colonoscopes (110-32,000 colony-forming units [CFUs]/mL) and from 80.6% (50/62) of the gastroscopes (100-33,000 CFUs/mL). Not all services followed recommended guidelines. Therefore, patients who underwent gastrointestinal endoscopies were exposed to diverse pathogens.

Swab culture monitoring of automated endoscope reprocessors after high-level disinfection.

AIM: To conduct a bacterial culture study for monitoring decontamination of automated endoscope reprocessors (AERs) after high-level disinfection (HLD). METHODS: From February 2006 to January 2011, authors conducted randomized consecutive sampling each month for 7 AERs. Authors collected a total of 420 swab cultures, including 300 cultures from 5 gastroscope AERs, and 120 cultures from 2 colonoscope AERs. Swab cultures were obtained from the residual water from the AERs after a full reprocessing cycle. Samples were cultured to test for aerobic bacteria, anaerobic bacteria, and mycobacterium tuberculosis. RESULTS: The positive culture rate of the AERs was 2.0% (6/300) for gastroscope AERs and 0.8% (1/120) for colonoscope AERs. All the positive cultures, including 6 from gastroscope and 1 from colonoscope AERs, showed monofloral colonization. Of the gastroscope AER samples, 50% (3/6) were colonized by aerobic bacterial and 50% (3/6) by fungal contaminations. CONCLUSION: A full reprocessing cycle of an AER with HLD is adequate for disinfection of the machine. Swab culture is a useful method for monitoring AER decontamination after each reprocessing cycle. Fungal contamination of AERs after reprocessing should also be kept in mind.

Reducing infection risk in colonoscopy.

Colonoscopy is a well recognized diagnostic and therapeutic tool. Endoscope reprocessing must be done correctly every time; a breach of protocol leading to transmission of infection has the potential to bring endoscopy to a halt. Standards exist that guide the practitioner in all health care settings to minimize the chance of transmission of infection. Safe injection practices and reprocessing of endoscopes using high-level disinfection and sterilization methods may help avert the risk of contracting possible infections during colonoscopy procedures.

Surveillance culture of endoscope to monitor the quality of high-level disinfection of gastrointestinal reprocessing.

BACKGROUND/AIMS: Inadequate reprocessing of endoscopes or endoscopic accessories may result in iatrogenic infection and present a risk to public health. The aim of this study is to utilize microbiological cultures of endoscopes to assess the adequacy of standard reprocessing procedures. METHODOLOGY: A prospective study to randomly cultures of endoscopes and colonoscopies immediately after the completion of the decontamination cycle monthly. The samples were obtained by flushing 50 ml sterile distilled water to the internal channel and collected into a sterile container. These samples were incubated at 37 degrees C and examined for bacterial growth. RESULTS: A total of 49 cultures were obtained from June to December in year 2005. Three out of 7 were culture positive in the first month initially, but after prolonged the soaking duration to 25 minutes, the subsequent cultures were reduced to 1 positive sample only. The positive culture rate was 18.4% (9/49), and 44.4% (4/9) in Monoflora culture and 55.6% (5/9) in Multi-flora. Upper endoscopes decontaminated by automated endoscopic washing machine labeled as number 5 was found persistently culture positive with varied organisms despite vigorous manual cleaning and prolonged disinfectant soaking duration. At repair, the relief valve in the automated endoscopes washing machine was damaged and disconnected. After repair, subsequent cultures were negative. CONCLUSIONS: Endoscopy culturing is a useful method to assess the effectiveness of standard reprocessing procedures. Servicing of automated endoscope washer regularly is mandatory to minimize cross infection and quality assurance.

[Effect of quality assessment assurance in 2002 (before starting the German colorectal cancer screening programme by colonoscopy) on the quality of reprocessing of flexible endoscopes--a nationwide analysis]. / Effekt der Qualitätssicherungsvereinbarung von 2002 (bei Einführung der Vorsorgekoloskopie) auf die Qualität der Aufbereitung flexibler Koloskope - eine bundesweite Analyse.

BACKGROUND: International studies in the 1990 s and the HYGEA study from Germany in 2002 revealed prevalences of around 50 % of microbiological contaminations in reprocessed flexible endoscopes. Before introducing the colorectal cancer screening programme by colonoscopy in Germany in 2002, the Kassenärztliche Bundesvereinigung (KBV) and the key stakeholders of the public health insurance system agreed on a quality assessment assurance for reprocessing endoscopes where the qualification for refund for colonoscopies from the public health system was made conditional on adequate qualifications of the gastroenterologist; on a minimum number of performed procedures per year; and on adequate endoscope reprocessing documented by negative surveillance cultures two times per year. This study is an implementation and outcome evaluation of the quality assessment assurance in colonoscopy in Germany. METHODS: The following data - per year and per Kassenärztliche Vereinigung (KV) - were obtained from the KBV: the number of endoscopic units performing therapeutic and/or screening colonoscopies within each KV; the results of all microbiological surveillance tests of reprocessing quality (two per year per unit); the number of failed surveillance tests and re-tests; and the number of qualifications for refund from the public health system cancelled due to repeated failure of microbiological surveillance tests. RESULTS: The percentages of actually performed hygiene control tests (out of those prescribed by the assurance system) reached 95 % already in 2004 and remained above or close to this level thereafter. After the introduction of the quality assessment assurance, the percentage of failed microbiological surveillance tests dropped significantly and steadily from close to 17 % in 2003 to below 4 % in 2007. CONCLUSIONS: This study evidences 1. the successful implementation of the quality assessment assurance in Germany and 2. a substantial improvement in the quality of reprocessing flexible endoscopes achieved by these measures with a drop from 50 % of failed tests observed before the introduction in 2000 - 2001 to below 4 % in 2007.

[Five years of the Robert Koch Institute guidelines for reprocessing of flexible endoscopes. A look back and a look forward]. / Fünf Jahre Empfehlungen der Kommission für Krankenhaushygiene zur Aufbereitung flexibler Endoskope. Blick zurück und Blick nach vorn.

In a short review the national and international reception of the German guidelines for reprocessing flexible endoscopes is presented. The recommendations of the guidelines are discussed in view of recent knowledge on old problems such as prion inactivation and new infectious diseases and new microorganisms such as SARS, avian influenza and C. difficile. New disinfectants and new methods for endoscope disinfection are mentioned, the importance of careful cleaning is underlined. The German guidelines of the Robert Koch Institute and the US Multi-Society guidelines, published in 2003, are compared. The discrepancies concerning recommendations for water quality for final rinsing and need of microbiological controls of endoscope reprocessing are stressed. Aspects not mentioned in the German guidelines, e.g. duration of storage after reprocessing and risk of infection transmission by the endo-washer, are discussed.

Endoscopic shuffling, infection control, and the clinical practice of push enteroscopy.

Failure to identify and diagnose the site and cause of obscure bleeding or some other gastrointestinal disorder may be an indication for push enteroscopy. During this procedure, a long, narrow, flexible gastrointestinal endoscope, known as a push enteroscope, is advanced into the upper gastrointestinal tract to examine and evaluate the proximal section (first one third) of the small bowel. Because of limited funding and inadequate instrument availability, some gastrointestinal endoscopy units may perform this procedure using a colonoscope instead of a push enteroscope. Although not specifically designed for push enteroscopy, colonoscopes are less expensive than push enteroscopes and readily available for clinical use in virtually every gastrointestinal endoscopy unit. The use of a colonoscope or other lower gastrointestinal endoscope to perform push enteroscopy or another upper gastrointestinal procedure (or the use of an upper gastrointestinal endoscope to perform a lower gastrointestinal procedure) is defined in this article as endoscopic shuffling. Although it is arguably efficient and cost effective (and in some instances may improve clinical outcomes), endoscopic shuffling raises a number of economic, legal, medical, and ethical questions and concerns, several of which are discussed in this article, with a particular focus on infection control.

A prospective study of the efficacy of routine decontamination for gastrointestinal endoscopes and the risk factors for failure.

BACKGROUND: Patient-ready endoscopes were monitored over an 80-week period to determine the efficacy of decontamination procedures in a busy endoscopy center. Decontamination failure was related to patient and procedural parameters. METHODS: Samples from patient-ready endoscopes were cultured aerobically and anaerobically and subjected to polymerase chain reaction (PCR) to detect hepatitis B virus (HBV), hepatitis C virus (HCV), and HIV. PCR to detect coliforms from 109 culture negative washes was used as a surrogate marker for biofilm in endoscopes. PCR was used to detect the presence of Helicobactor pylori in endoscopes used on infected patients. Procedural information such as biopsy retrieval, endoscope number, diagnosis, attending personnel, and decontamination system procedures was collected. RESULTS: Gastroscopes (n = 1,376) and colonoscopes (n = 987) were equally contaminated (1.8% vs 1.9%, respectively) with low numbers of organisms commonly isolated from the nasopharynx and/or feces. Only 1 wash contained viral nucleic acid (HCV). There was a significant correlation (P < .001) between the number of times a patient-ready endoscope was contaminated and its frequency of use. Colonoscopes used on patients with gastrointestinal disease were significantly more likely to remain contaminated through the decontamination process (P < .05). All other patient, staff, and decontamination system parameters remained not statistically significant. Coliform DNA was detected in 40% of culture-negative washes collected from patient-ready endoscopes, suggesting the presence of biofilm. No H pylori DNA was detected. CONCLUSION: Recommended decontamination procedures do not entirely eliminate persistence of low numbers of organisms on a few endoscopes, but this is unlikely to cause serious consequences in patients. Bacterial biofilm is difficult to remove and may explain this low-level persistence.