Duodenoscope-associated infections: a review

The Application of Multifunctional Endoscope Transport Carts in Bedside Endoscopy in Intensive Care Unit Patients

Background

This study aimed to investigate whether the application of multifunctional endoscope transport carts, in bedside endoscopy in intensive care unit (ICU) patients, can improve the cleaning quality of the endoscopes.

Methods

A total of 175 endoscopes, used for bedside endoscopy in ICU patients in a hospital in China during November 2023 to January 2024, were randomly classified into the control group (n=88) and the experimental group (n=87). Multifunctional transport carts were used to deliver the endoscopes in the experimental group and traditionally used transport trolleys were used in the control group. Adenosine triphosphate (ATP) tests were performed to measure the relative light unit (RLU) values for the outer surfaces and forceps channels of the endoscopes, and a satisfaction survey was conducted with nurses who used the endoscope transport trolleys/carts and the endoscope cleaning staff.

Results

The ATP values for the outer surfaces and forceps channels of the endoscopes in the experimental group were 10.0 (6.0, 17.0) RLU and 7.0 (4.0, 11.0) RLU, respectively, lower than 33.5 (9.3, 77.0) RLU for outer surfaces and 14.0 (5.0, 39.8) RLU for forceps channels in the control group. The pass rates for cleaning quality of the outer surfaces and channels of the endoscopes in the experimental group were 98.9% and 100%, respectively, higher than 88.6% for outer surfaces and 93.2% for channels in the control group (P < 0.05). The satisfaction scores of the nurses who used the multifunctional endoscope transport carts and the endoscope cleaning staff in the experimental group were 39.7±1.87 and 18.45±1.41, respectively, higher than 19.83±2.08 for nurses and 9.08±1.71 for cleaning staff in the control group (P < 0.05).

Conclusion

The application of multifunctional endoscope transport carts in bedside endoscopy in ICU patients could improve the quality of endoscope cleaning.

Novel water-based automated endoscope cleaning process vs conventional manual cleaning for reducing duodenoscope contamination

Background and study aims

Duodenoscope contamination remains a persistent problem, exposing patients to infection risks. Automation in reprocessing may limit human error, reduce workload, and increase uniformity and traceability. However, its effectiveness should be evaluated before implementation. This study assessed the impact of implementing a novel water-based automated endoscope cleaning process on duodenoscope contamination.

Methods

This before-and-after intervention study compared duodenoscope cleaning methods. From January 2022 to December 2023, conventional manual cleaning was used. From January 2024 to June 2024, the AquaTYPHOON system (AT) replaced manual cleaning. Cultures from Pentax ED34-i10T2 patient-ready duodenoscopes were collected. The main outcome was the contamination rate with microorganisms of gut or oral origin (MGO). Secondary outcomes included contamination with solely gut bacteria. Non-inferiority of the AT was tested using a generalized estimating equation with a non-inferiority margin of 5%.

Results

During the manual cleaning period, 333 duodenoscope cultures of eight duodenoscopes were collected; during the AT period, 100 cultures were collected. Pre-introduction of the AT, the contamination rate with MGO was 21.6%, which fell to 16% post-introduction (risk difference: -5.6%, upper bound 90% confidence interval [CI] 6.8%). For gut bacteria, the contamination rate decreased from 14.4% to 9% (risk difference: -5.4%, upper bound 90% CI 3.9%), indicating non-inferiority.

Conclusions

AT reduced the contamination rate with MGO, but non-inferiority was not demonstrated. For gut bacteria, AT was non-inferior to manual cleaning. These results are promising. However, future studies should confirm these findings in larger samples and explore other advantages of using the AT in duodenoscope cleaning.

Evaluating the risk of duodenoscope-associated colonization and duodenoscope-associated infection: a prospective observational study

BACKGROUND

The risk of duodenoscope-associated colonization (DAC) and infection (DAI) after endoscopic retrograde cholangiopancreatography (ERCP) with a contaminated duodenoscope remains unknown. Determining the incidence of these events is crucial for developing prevention strategies.

AIM

To assess the incidence of DAC and DAI.

METHODS

This prospective observational study included adult patients who underwent ERCP from January 2022 to December 2023. Duodenoscopes were sampled prior to each procedure. Contamination was defined as the presence of micro-organisms of gut or oral origin (MGO). Post ERCP, upon availability of culture results, patients exposed to contaminated duodenoscopes were asked to provide a stool sample and were followed for six months. Micro-organisms isolated from patient samples and clinical cultures were compared with those found in the duodenoscopes. Whole-genome sequencing (WGS) was used to confirm DAC or DAI.

FINDINGS

Among 341 ERCP patients, 73 (21.4%) procedures involved MGO-contaminated duodenoscopes. No duodenoscope-associated outbreaks occurred during the study. Stool samples were returned by 45 of the 73 patients (61.6%). Additionally, 80 MGOs from clinical cultures and 37 residual samples were stored. WGS was performed on eight duodenoscope-patient micro-organism pairs from six patients. No DAC or DAI cases were detected.

CONCLUSION

In a non-outbreak setting, supported by monthly routine microbiological surveillance and a quarantine protocol for duodenoscopes, the risk of DAC and DAI appears low. These findings suggest limited value in intensive patient surveillance for DACs/DAIs. Further research is warranted to confirm these results and address knowledge gaps regarding risk factors for DACs and DAIs.

Contamination of Disposable Distal Cap Duodenoscopes and Detachable Elevator Duodenoscopes After Reprocessing: A Randomized Trial

BACKGROUND AND AIM

To reduce bacterial contamination after reprocessing, various new designs of duodenoscopes have been developed to better expose the elevator complex for cleaning. We compared the rates of bacterial contamination and organic residue in disposable distal cap duodenoscopes and detachable elevator duodenoscopes after manual cleaning and high-level disinfection (HLD), as well as their cost-effectiveness.

METHODS

A total of 162 duodenoscopes were randomly assigned to either Group A (disposable distal caps; n = 81) or Group B (detachable elevator; n = 81). A total of 324 samples from the elevator were collected for culture following manual cleaning (n = 81 in each group) and HLD (n = 81 in each group), followed by the adenosine triphosphate (ATP) testing for organic residue.

RESULTS

After manual cleaning, there was no difference in bacterial contamination rates (8.6% vs. 8.6%; p = 1.00) and mean ATP levels (164.6 ± 257.5 vs. 158.1 ± 286.1 RLUs; p = 0.88) between Groups A and B. After HLD, no bacterial contamination was observed in either group and the mean ATP levels were very low with no significant difference between the two groups (30.1 ± 45.3 vs. 37.5 ± 51.9 RLUs; p = 0.68). The expense in reprocessing (excluding the scope cost) for Group A was lower (2099 USD) than Group B (3854 USD) in providing comparable scope cleanliness.

CONCLUSION

After manual cleaning, the bacterial contamination rate and organic residue levels in detachable elevator duodenoscopes and disposable distal caps duodenoscopes were comparable. No bacterial contamination was detected in either type of duodenoscope after reprocessing. Apart from the initial differences in scope cost, the disposable distal cap duodenoscope had lower cost on disposable items to have comparable disinfection result.

Environmental footprint and material composition comparison of single-use and reusable duodenoscopes

BACKGROUND

Infection outbreaks associated with contaminated reusable duodenoscopes (RUDs) have induced the development of novel single-use duodenoscopes (SUDs). This study aimed to analyze the material composition and life cycle assessment (LCA) of RUDs and SUDs to assess the sustainability of global and partial SUD implementation.

METHODS

A single-center study evaluated material composition analysis and LCA of one RUD and two SUDs from different manufacturers (A/B). Material composition analysis was performed to evaluate the thermochemical properties of the duodenoscope components. The carbon footprint was calculated using environmental software. We compared the sustainability strategies of universal use of RUDs, frequent use of RUDs with occasional SUDs, and universal use of SUDs over the lifetime of one RUD.

RESULTS

RUDs were substantially heavier (3489 g) than both SUD-A (943 g) and SUD-B (716 g). RUDs were mainly metal alloys (95%), whereas SUDs were mainly plastic polymers and resins (70%-81%). The LCA demonstrated the sustainability of RUDs, with a life cycle carbon footprint 62-82 times lower than universal use of SUDs (152 vs. 10 512-12 640 kg CO2eq) and 10 times lower than occasional use of SUDs (152 vs. 1417-1677 kg CO2eq). Differences were observed between SUD-A and SUD-B (7.9 vs. 6.6 kg CO2eq per endoscope). End-of-life incineration emissions for SUDs were the greatest environmental contributors.

CONCLUSIONS

Widespread adoption of SUDs has greater environmental challenges; it requires a balance between infection control and environmental responsibility. Carbon footprint labelling can help healthcare institutions make sustainable choices and promote environmentally responsible healthcare practices.

Contaminated duodenoscopes in ERCP: sensitivity of detection and risk of underdetection

BACKGROUND AND AIMS

Periodic duodenoscope cultures are essential to timely detect contamination, but their sensitivity remains unknown. This study aims to determine the sensitivity of duodenoscope cultures and to estimate the prevalence of contaminated duodenoscope use.

METHODS

We combined duodenoscope microbiologic surveillance data from March 2015 to June 2022 with usage data to evaluate patient exposure to duodenoscopes contaminated with microorganisms of gut or oral origin (MGO). We identified duodenoscopes with repeated species-level contamination within a year and used molecular typing to confirm genetic relatedness. Genetically related microorganisms over multiple duodenoscope cultures of a single duodenoscope indicated a period of sustained contamination, and a cluster was defined as overlapping periods of sustained contamination between different duodenoscopes. If microorganisms were not available for molecular analysis, we marked the period as unconfirmed. A sample was defined as false negative if it did not show the target microorganism(s) in a period of sustained contamination. We used 3 scenarios to hypothesize about contaminated use and culture sensitivity.

RESULTS

We included 556 duodenoscope cultures with 185 (33.3%) contaminated with MGO. The total usage of duodenoscopes was 5226. We identified 1 period of sustained contamination, 6 unconfirmed periods, and 2 clusters. Depending on our scenario assumptions, the percentage of contaminated use varied from 12.3% to 23.7% and culture sensitivity ranged from 82.2% to 98.9%.

CONCLUSIONS

Limited sensitivity of duodenoscope cultures leads to improper clearance of duodenoscopes for clinical use, increasing risks of outbreaks. The applicability of a single culture to end a duodenoscope's quarantine should be re-evaluated.

Gastrointestinal endoscopy 30-day-associated bacteremia: Nonoutbreak 5-year review in an inner-city, tertiary-care hospital

BACKGROUND

Gastrointestinal endoscopic procedures (GIEP's) are an essential part of patient care both diagnostically and therapeutically. Post-GIEP infections may be higher than previously reported and may not have been accurately captured in the past. The aim of this study was to determine the incidence and associated factors of bacteremia associated with GIEP's.

METHODS

This is retrospective study of GIEPs performed over a five-year period (2018-2022) at an academic medical center. Electronic health records (EHR) identified GIEPs and positive blood cultures within 30 days of procedure. Statistical analysis was performed using non-parametric testing to compare variables due to the small number of positive blood cultures.

RESULTS

EHR identified 18,986 GIEP's and 52 true and unique bacteremia out of 17,093 blood cultures during the five-year study period. The highest rate of positive blood culture of 2.84% (18/ 634) was associated with ERCP and the lowest 0.08% (7/ 9029) was associated with colonoscopy.

DISCUSSION

Our study showed a reflection of the endemic rate of bacteremia post GIEP's. Our study cannot differentiate endogenous infection versus contaminated (exogenous) endoscopes. ERCP procedures are disproportionately associated with higher incidence of bacteremia.

CONCLUSIONS

Clinical surveillance in non-outbreak settings is essential for estimating GIEP related infections. It should be combined with endoscopic reprocessing audits for appropriate prevention of GIEP associated infections.

Effect of simethicone on the bactericidal efficacy of a high-level disinfectant

Introduction. Simethicone is an over-the-counter product that is frequently used by clinicians during endoscopic procedures to reduce foaming and improve visualization. Published studies have found simethicone residue on endoscopes after cleaning and disinfecting the devices as per the manufacturer's instructions. Some literature suggests that simethicone residue may reduce disinfection efficacy and increase the risk of patient infections.Gap Statement. However, there appears to be a lack of direct evidence in the literature to either disprove this or correlate simethicone presence with an increased microbial risk.Aim: Research was conducted to evaluate the in vitro impact of simethicone on disinfection efficacy.Methodology. Bacteria were grown in a microtitre plate assay in the presence of a range of simethicone concentrations and then treated with a disinfectant. Bacterial growth was assessed by spotting each microtitre well onto an agar plate.Results. The results demonstrated that, under the conditions tested, simethicone did not reduce the efficacy of Cidex ortho-phthalaldehyde disinfectant, which demonstrated at least a 6-log unit reduction in bacterial viability. Additional experiments showed that direct exposure to 66 mg ml-1 of simethicone reduced bacterial viability.Conclusion. These results indicate that simethicone may not reduce the bactericidal efficacy of disinfectant during reprocessing, under certain conditions.

Carbapenem-resistant Enterobacterales sepsis following endoscopic retrograde cholangiopancreatography: risk factors for 30-day all-cause mortality and the development of a nomogram based on a retrospective cohort

BACKGROUND

Endoscopic retrograde cholangiopancreatography (ERCP) has become a routine endoscopic procedure that is essential for diagnosing and managing various conditions, including gallstone extraction and the treatment of bile duct and pancreatic tumors. Despite its efficacy, post-ERCP infections - particularly those caused by carbapenem-resistant Enterobacterales (CRE) - present significant risks. These risks highlight the need for accurate predictive models to enhance postprocedural care, reduce the mortality risk associated with post-ERCP CRE sepsis, and improve patient outcomes in the context of increasing antibiotic resistance.

OBJECTIVE

This study aimed to examine the risk factors for 30-day mortality in patients with CRE sepsis following ERCP and to develop a nomogram for accurately predicting 30-day mortality risk.

METHODS

Data from 195 patients who experienced post-ERCP CRE sepsis between January 2010 and December 2022 were analyzed. Variable selection was optimized via the least absolute shrinkage and selection operator (LASSO) regression model. Multivariate logistic regression analysis was then employed to develop a predictive model, which was evaluated in terms of discrimination, calibration, and clinical utility. Internal validation was achieved through bootstrapping.

RESULTS

The nomogram included the following predictors: age > 80 years (hazard ratio [HR] 2.61), intensive care unit (ICU) admission within 90 days prior to ERCP (HR 2.64), hypoproteinemia (HR 4.55), quick Pitt bacteremia score ≥ 2 (HR 2.61), post-ERCP pancreatitis (HR 2.52), inappropriate empirical therapy (HR 3.48), delayed definitive therapy (HR 2.64), and short treatment duration (< 10 days) (HR 5.03). The model demonstrated strong discrimination and calibration.

CONCLUSIONS

This study identified significant risk factors associated with 30-day mortality in patients with post-ERCP CRE sepsis and developed a nomogram to accurately predict this risk. This tool enables healthcare practitioners to provide personalized risk assessments and promptly administer appropriate therapies against CRE, thereby reducing mortality rates.

Green endoscopy, one step toward a sustainable future: Literature review

Rapid climate change or climate crisis is one of the most serious emergencies of the 21st century, accounting for highly impactful and irreversible changes worldwide. Climate crisis can also affect the epidemiology and disease burden of gastrointestinal diseases because they have a connection with environmental factors and nutrition. Gastrointestinal endoscopy is a highly intensive procedure with a significant contribution to greenhouse gas (GHG) emissions. Moreover, endoscopy is the third highest generator of waste in healthcare facilities with significant contributions to carbon footprint. The main sources of direct carbon emission in endoscopy are use of high-powered consumption devices (e.g. computers, anesthesia machines, wash machines for reprocessing, scope processors, and lighting) and waste production derived mainly from use of disposable devices. Indirect sources of emissions are those derived from heating and cooling of facilities, processing of histological samples, and transportation of patients and materials. Consequently, sustainable endoscopy and climate change have been the focus of discussions between endoscopy providers and professional societies with the aim of taking action to reduce environmental impact. The term "green endoscopy" refers to the practice of gastroenterology that aims to raise awareness, assess, and reduce endoscopy´s environmental impact. Nevertheless, while awareness has been growing, guidance about practical interventions to reduce the carbon footprint of gastrointestinal endoscopy are lacking. This review aims to summarize current data regarding the impact of endoscopy on GHG emissions and possible strategies to mitigate this phenomenon. Further, we aim to promote the evolution of a more sustainable "green endoscopy".

Uncovering the spread of drug-resistant bacteria through next-generation sequencing based surveillance: transmission of extended-spectrum β-lactamase-producing Enterobacterales by a contaminated duodenoscope

Contamination of duodenoscopes is a significant concern due to the transmission of multidrug-resistant organisms (MDROs) among patients who undergo endoscopic retrograde cholangiopancreatography (ERCP), resulting in outbreaks worldwide. In July 2020, it was determined that three different patients, all had undergone ERCP with the same duodenoscope, were infected. Two patients were infected with blaCTX-M-15 encoding Citrobacter freundii, one experiencing a bloodstream infection and the other a urinary tract infection, while another patient had a bloodstream infection caused by blaSHV-12 encoding Klebsiella pneumoniae. Molecular characterization of isolates was available as every ESBL-producing isolate undergoes Next-Generation Sequencing (NGS) for comprehensive genomic analysis in our center. After withdrawing the suspected duodenoscope, we initiated comprehensive epidemiological research, encompassing case investigations, along with a thorough duodenoscope investigation. Screening of patients who had undergone ERCP with the implicated duodenoscope, as well as a selection of hospitalized patients who had ERCP with a different duodenoscope during the outbreak period, led to the discovery of three additional cases of colonization in addition to the three infections initially detected. No microorganisms were detected in eight routine culture samples retrieved from the suspected duodenoscope. Only after destructive dismantling of the duodenoscope, the forceps elevator was found to be positive for blaSHV-12 encoding K. pneumoniae which was identical to the isolates detected in three patients. This study highlights the importance of using NGS to monitor the transmission of MDROs and demonstrates that standard cultures may fail to detect contaminated medical equipment such as duodenoscopes.

Effect of a novel endoscope cleaning brush on duodenoscope contamination

BACKGROUND

Current duodenoscope reprocessing protocols are insufficient to prevent contamination and require adaptations to prevent endoscopy-associated infections (EAIs). This study aimed to investigate the effect of a new endoscope cleaning brush on the contamination rate of ready-to-use duodenoscopes.

METHODS

This retrospective before-and-after intervention study collected duodenoscope surveillance culture results from March 2018 to June 2022. Contamination was defined as ≥1 colony-forming unit of a microorganism of gut or oral origin (MGO). In December 2020, an endoscope cleaning brush with a sweeper design was introduced as an intervention in the manual cleaning of duodenoscopes. A logistic mixed-effects model was used to study the effects of this intervention.

RESULTS

Data were collected from 176 culture sets before the new brush's introduction and 81 culture sets afterwards. Pre-introduction, culture sets positive with an MGO comprised 45.5% (95%CI 38.3%-52.8%; 80/176), decreasing to 17.3% (95%CI 10.6%-26.9%; 14/81) after implementation of the new brush. Compared with the former brush, duodenoscopes cleaned with the new brush had lower odds of contamination with MGOs (adjusted odds ratio 0.25, 95%CI 0.11-0.58; P=0.001) CONCLUSIONS: Use of the new brush in manual cleaning reduced contamination with MGOs and is expected to prevent EAIs. These findings should be confirmed in future prospective randomized studies.

Comparing the Safety and Efficacy of Two Commercially Available Single-Use Duodenoscopes: A Multicenter Study

INTRODUCTION

Single-use disposable duodenoscopes (SDD) have been developed to mitigate infectious risks related to reusable duodenoscopes. The aim of this study is to compare the safety and efficacy of the two available SDDs in the United States.

METHODS

We conducted a comparative study of 2 SDD in consecutive ERCP procedures performed by expert endoscopists from 9 academic centers. Performance ratings, procedure details, and adverse events were collected.

RESULTS

A total of 201 patients were included: 129 patients underwent ERCP with Exalt (mean age 63, Males- 66 (51%), 72 with aScope Duodeno (mean age 65, males=30 (42%). A majority of endoscopists had performed >2000 ERCPs in both groups (71% Exalt, 93% aScope Duodeno). Technical success was 92% in both groups (n=119 Exalt-group, n=66 aScope-Duodeno-group). The procedural complexity for the ERCP cases performed were: Grade 1: 35 cases (18%), Grade 2: 83 cases (41%), Grade 3: 65 cases (32%), and Grade 4: 18 cases (9%). Thirteen patients (10%) from the Exalt group and 16 patients (22%) from the aScope Duodeno group required conversion to a reusable duodenoscope. On a scale of 1 to 5, Exalt and aScope Duodeno, respectively, were rated: 2.31 versus 2.60 for location and visualization quality, 1.38 versus 1.57 for maneuverability based on papillary orientation, 1.48 versus 1.15 for suction/air control, and 2.31 versus 2.34 for elevator efficiency. None of the adverse events were related to the SDDs.

CONCLUSIONS

The 2 SDDs were comparable. Further ongoing enhancements to these devices will improve maneuverability and clinical effectiveness.

Costs of purchase, maintenance, microbiological control, and reprocessing of a reusable duodenoscope

Background and study aims The costs of reusable endoscope reprocessing have been evaluated, yet external validity of the findings remains challenging. The aim of this study was to assess the costs of purchase, maintenance, microbiological control, and reprocessing of a reusable duodenoscope per endoscopic retrograde cholangiopancreatography (ERCP) in France. Study findings exclude the costs of infection, downtime due to breakdown, reprocessing single-use material disposal, and device disposal, all of which should also be considered. Materials and methods The study encompassed both observational and theoretical approaches. Observational data were collected in four hospitals, from December 2019 to December 2020, with an ad hoc survey, based on 2016 and 2018 national guidelines for duodenoscope reprocessing. Costs were modeled, using the same guidelines, assuming a mean workload of 223 ERCP/duodenoscope/year. Results The mean observed cost of purchase, maintenance, microbiological control, reprocessing (human resources and consumables), and overhead (additional 35%) with a reusable duodenoscope was €80.23 (standard deviation €3.77) per ERCP. The corresponding mean theoretical cost was €182.71 for manual reprocessing without endoscope drying cabinet (EDC), €191.36 for manual reprocessing with EDC, €235.25 for automated endoscope reprocessing (AER) without EDC, and €253.62 for AER with EDC. Conclusions Because procedures, equipment, volume activity, number of duodenoscopes, human resources, and internal work organizations are hospital-dependent, observed costs varied between hospitals. Theoretical costs were higher than observed costs, showing that the theoretical approach is not sufficient. Hypotheses to explain the difference between the two approaches include failing to measure some costs in the survey and challenges in guideline implementation.

New Hydrogels Nanocomposites Based on Chitosan, 2-Formylphenylboronic Acid, and ZnO Nanoparticles as Promising Disinfectants for Duodenoscopes Reprocessing

New hydrogels nanocomposites, based on iminoboronate hydrogels and ZnO nanoparticles (ZnO-NPs), were obtained and characterised in order to develop a new class of disinfectants able to fight the nosocomial infections produced by duodenoscopes investigation procedures. The formation of the imine linkages between chitosan and the aldehyde was demonstrated using NMR and FTIR spectroscopy, while the supramolecular architecture of the developed systems was evaluated via wide-angle X-ray diffraction and polarised optical microscopy. The morphological characterisation of the systems via scanning electron microscopy revealed the highly porous structure of the materials, in which no ZnO agglomeration could be observed, indicating the very fine and homogenous encapsulation of the nanoparticles into the hydrogels. The newly synthetised hydrogels nanocomposites was proven to have synergistic antimicrobial properties, being very efficient as disinfectants against reference strains as: Enterococcus faecalis, Klebsiella pneumoniae, and Candida albicans.

Single-use duodenoscopes compared with reusable duodenoscopes in patients carrying multidrug-resistant microorganisms: a break-even cost analysis

Background and study aims  Single-use duodenoscopes can prevent transmission of microorganisms through contaminated reusable duodenoscopes. Concerns regarding their economic and environmental impact impede the transition to single-use duodenoscopes. This study investigated the costs associated with two scenarios in which single-use duodenoscopes are used in patients carrying multidrug-resistant microorganisms (MDROs). Methods  Break-even costs for single-use duodenoscopes were calculated for two scenarios in which patients were screened for MDRO carriage before undergoing endoscopic retrograde cholangiopancreatography (ERCP). Only direct costs related to the endoscopy were taken into consideration. In Scenario 1, patients were screened through microbiological culturing with a lag time in receiving the test result. In Scenario 2, screening was performed using GeneXpert analysis providing a rapid read-out. Calculations were performed using data from a Dutch tertiary care center and also with US healthcare data. Results  In the Dutch situation, single-use duodenoscopes needed to be priced at a maximum of € 140 to € 250 to break-even. In the US analyses, break-even costs varied widely, depending on the duodenoscope-associated infection costs used, ERCP volume, and infection risk. The break-even costs in Scenario 1 ranged between $78.21 and $2,747.54 and in Scenario 2, between $248.89 and $2,209.23. Conclusions  This study showed that a crossover scenario in which single-use duodenoscopes are only used in patients carrying MDROs could be an economically viable alternative to a complete transition to single-use duodenoscopes. In the Dutch setting, single-use duodenoscopes need to be priced much lower than in the United States to reach a per-procedure cost that is comparable with a scenario using reusable duodenoscopes exclusively.

Investigation of the efficacy of an innovative endoscope drying and storage method in a simulated ERCP setting

Background and study aims  Drying after cleaning and disinfection is essential in the reprocessing of endoscopes since microorganisms can grow and form biofilms on wet surfaces. In this experimental non-clinical study, we investigated the efficacy of a novel, fast-drying method when reprocessing duodenoscopes. Methods  During a series of 40 tests, three duodenoscopes were exposed to an artificial test soil containing supraphysiological loads of four types of gut microorganisms in a non-clinical ERCP simulation, followed by reprocessing and drying with the PlasmaTYPHOON. Cultures of the distal tip and working channel were acquired immediately after automated decontamination and after drying with the PlasmaTYPHOON. Cobalt chloride paper tests and borescope inspections were used to evaluate drying efficacy. Results  Contamination of the working channels dropped from 86.4 % post-decontamination to 33.6 % post-drying, with 94 % of the positive post-drying samples belonging to one duodenoscope. This duodenoscope showed persistent contamination with P. aeruginosa in the working channel. The other two duodenoscopes only showed low levels of P. aeruginosa in post-decontamination channel samples, but not after drying. Cobalt chloride paper tests and borescope inspections revealed good drying efficacy. Conclusions  Positive cultures for gut microorganisms were often found in wet endoscopes post-decontamination. The PlasmaTYPHOON is an effective fast-drying method capable of abolishing nearly all remaining microorganisms after decontamination provided no biofilm has developed, even when using a supraphysiological concentration of bacterial load. The clinical use of the PlasmaTYPHOON has the potential to reduce endoscope contamination, the use of wet contaminated endoscopes and therefore the risk of patient infection.

Production and possible reduction of greenhouse gases produced during GI endoscopy activity: a systematic review of available literature

BACKGROUND AND AIMS

Greenhouse gases (GHGs) that trap heat in the atmosphere are composed of carbon dioxide (CO2), methane, nitrous oxide and fluorinated gases (synthetic hydrofluorocarbons, perfluorocarbons and nitrogen trifluoride). In the USA, the health sector accounts for 8.5% of total GHG emissions. The primary objective of this systematic review was to critically analyse the carbon emissions data from GI endoscopic activity.

DESIGN

The GI endoscopy carbon cycle was evaluated at preprocedural, intraprocedural and postprocedural levels. We performed a systematic literature search of articles published on these issues until 30 June 2022 and discussed these available data on endoscopy unit GHG carbon cycle, barriers to reduce GHG emissions and potential solutions. The inclusion criteria were any full-text articles (observational, clinical trials, brief communications, case series and editorials) reporting waste generation from GI endoscopy. Abstracts, news articles and conference proceedings were excluded.

RESULTS

Our search yielded 393 records in PubMed, 1708 in Embase and 24 in Google Scholar. After application of inclusion and exclusion factors, we focused on 9 fulllength articles in detail, only 3 of them were cross-sectional studies (all from the USA), the others reviews or position statements. Therefore, the quality of the studies could not be assessed due to heterogeneity in definitions and amount of emissions.

CONCLUSIONS

Recognition of carbon emissions generated by GI endoscopy activity is critical. Although multiple limitations exists for quantification of these emission, there is an urgent need for collecting proper data as well as examining novel methods for reduction of these emissions for a sustainable endoscopic practices in the future.

How effective are the alcohol flush and drying cycles of automated endoscope reprocessors? Stripped endoscope model

BACKGROUND

Effective drying of the internal channels of endoscopes is essential to prevent the growth of water-borne pathogens and to assure adequate sterilization with vaporized hydrogen peroxide or ethylene oxide. The aim of this study was to evaluate the dryness of endoscopes after a routine disinfection process in an automated endoscope reprocessor.

METHODS

Stripped endoscopes (SE) that allow for visual inspection of the inside channels were reprocessed per protocol in a large urban medical center, with a 3-minute or 10-minute air flush following reprocessing. SE was hung and observed for any water within the channels after reprocessing and after a week of ambient storage. Ready-for-use endoscopes were also randomly spot-checked for moisture visually and with moisture detection paper.

RESULTS

All SE were grossly wet after HLD with a 3-minute air flush, despite alcohol flush and drying cycle. The 10-minute air flush was effective at drying the biopsy/suction channel, but not the air/water channels. Hanging had limited effect, being most effective in the biopsy/suction channels. Of the 77 ready-for-use respiratory and gastrointestinal endoscopes assessed, 37 (48.1%) showed evidence of retained moisture.

CONCLUSIONS

Air flush cycles commonly used in the final steps of automated endoscope reprocessing may not adequately dry endoscope channels, particularly the narrower diameter air/water channels. An extended 10-minute air flush appears effective at drying the larger biopsy/suction channel, but has limited effect on the air/water channels.

Slippery quartz surfaces for anti‐fouling optical windows

The surface of camera‐based medical devices is easily smeared by blood and fog during the surgical procedure, causing visual field loss and bringing great distress to both doctors and patients. In this article, a slippery liquid‐infused porous surface (SLIPS) on a quartz window surface that can repel various liquids, especially blood droplets is reported. A femtosecond laser pulse train was used to create periodic microhole structures on the silica surface. The subsequent low surface energy treatment and lubricant infusion led to the successful preparation of a slippery surface. Such blood‐repellent windows exhibited high transparency, great antifogging, and antibacterial properties. In addition, the slippery ability of the as‐prepared surface exhibited outstanding stability since the surface could withstand harsh treatments/environments, such as repeated pipette scratches and immersion in different pH solutions. The as‐prepared millimeter‐sized quartz samples with SLIPS were attached to the endoscope lens as a protective coating and could maintain high visibility after repeated immersion in blood. We believe that the coating developed in this study will provide inspiration for the design of next‐generation endoscopes or other camera‐guided devices that will resist fouling, keep clear vision, and reduce operation time, thus offering great potential applications in lesion diagnosis and therapy.

A prospective, multicenter, clinical study of duodenoscope contamination after reprocessing

OBJECTIVE

Several clinical procedures utilize duodenoscopes, which are processed for reuse after the procedures are completed. However, infection outbreaks due to improper duodenoscope processing occur frequently. To address this, we aimed to assess the contamination rates of duodenoscopes after reprocessing in nonoutbreak settings.

DESIGN AND SETTING

Prospective study in 16 clinical sites in the United States.

METHODS

We sampled and cultured reprocessed duodenoscopes following the FDA/CDC/ASM guideline; "Duodenoscope Surveillance Sampling and Culturing - Reducing the Risks of Infection." High-concern (HC) organisms were those highly associated with disease, including gram-negative rods, Staphylococcus aureus, Staphylococcus lugdunensis, β-hemolytic Streptococcus, Enterococcus spp, and yeasts. We evaluated duodenoscopes with ≥1 CFU of organisms after reprocessing. The reprocessing environments were also sampled and cultured.

RESULTS

We assessed 859 newer-model (NM) duodenoscopes (TJF-Q180V) and 850 older-model (OM) duodenoscopes (TJF-160F/VF); of these, 35 NM samples (4.1%) and 56 OM samples (6.6%) were contaminated with HC organisms. We detected and classified the HC organisms as gastrointestinal (45.4%), human origin (16.7%), environmental (24.1%), waterborne (13.0%), and unidentified (0.9%).

CONCLUSIONS

We detected an overall HC contamination rate of 5.3% in nonoutbreak settings. Although the relationship between endoscopic contamination and the occurrence of infections remains unclear, attempts should continue to be made to further reduce contamination rates. Additional improvements to the manufacturer's instructions for use, human factors during the reprocessing procedure, ongoing training programs, cleanliness of reprocessing environments, and the design of the distal end of the duodenoscope should be considered.

Sustainability in gastroenterology and digestive endoscopy: Position Paper from the Italian Association of Hospital Gastroenterologists and Digestive Endoscopists (AIGO)

Climate crisis is dramatically changing life on earth. Environmental sustainability and waste management are rapidly gaining centrality in quality improvement strategies of healthcare, especially in procedure-dominant fields such as gastroenterology and digestive endoscopy. Therefore, healthcare interventions and endoscopic procedures must be evaluated through the 'triple bottom line' of financial, social, and environmental impact. The purpose of the paper is to provide information on the carbon footprint of gastroenterology and digestive endoscopy and outline a set of measures that the sector can take to reduce the emission of greenhouse gases while improving patient outcomes. Scientific societies, hospital executives, single endoscopic units can structure health policies and investment to build a "green endoscopy". The AIGO study group reinforces the role of gastrointestinal endoscopy professionals as advocates of sustainability in digestive endoscopy. The "green endoscopy" can shape a more sustainable health service and lead to an equitable, climate-smart, and healthier future.

High Prevalence Rate of Microbial Contamination in Patient-Ready Gastrointestinal Endoscopes in Tehran, Iran: an Alarming Sign for the Occurrence of Severe Outbreaks

An alarmingly increasing number of outbreaks caused by contaminated gastrointestinal (GI) endoscopes are being reported as a particularly concerning issue. This study is the first large-scale multicenter survey to evaluate the contamination of GI endoscopes in Tehran, Iran. This multicenter study was conducted among 15 tertiary referral and specialized gastrointestinal settings. Reprocessed GI endoscopes were sampled by the sequence of the flush-brush-flush method. Bacterial and viral contamination, as well as antimicrobial resistance, were explored by culture and molecular assays. A total of 133 reprocessed and ready-to-use GI endoscopes were investigated. In phase I and phase II, 47% and 32%, respectively, of the GI endoscopes were determined to be contaminated. GI flora was the most prevalent contaminant isolated from GI endoscopes, in which the most predominant bacteria were Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae, in both phase I and II evaluations. The majority of the isolated bacteria in the current study were considered multidrug-resistant organisms (MDROs). More importantly, we recovered carbapenem-resistant nonfermentative Gram-negative bacilli (CRNFGNB), carbapenem-resistant Enterobacterales (CRE), extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (ESBL-E), multidrug-resistant Clostridioides difficile, vancomycin-resistant Enterococcus (VRE), and drug-resistant Candida spp. Disconcertingly, our molecular assays revealed contamination of some reprocessed GI endoscopes with hepatitis B virus (HBV), hepatitis C virus (HCV), and even HIV. This multicenter study indicates a higher-than-expected contamination rate among reprocessed and ready-for-patient-use GI endoscopes, which suggests a higher-than-expected endoscopy-associated infection (EAI) risk, and potentially, morbidity and mortality rate, associated with endoscopy procedures in Tehran, Iran. IMPORTANCE In the light of severe outbreaks caused by multidrug-resistant microorganisms due to contaminated GI endoscopes, understanding to what extent GI endoscopes are inadequately reprocessed is crucial. Several studies assessed contamination of GI endoscopes with various outcomes across the world; however, the prevalence and risk factors of contaminated GI endoscopes and potential subsequent nosocomial spread are still unknown in Iran. The present study is the first large-scale multicenter survey to evaluate the microbial contamination of repossessed and ready-to-use GI endoscopes in Tehran, Iran. Our study showed a higher-than-expected contamination rate among reprocessed GI endoscopes, which suggests potential seeding of deadly but preventable outbreaks associated with endoscopy procedures in Iran. These results suggest that the current reprocessing and process control guidelines do not suffice in Iran. The current study is of particular importance and could provide insights into unrecognized and unidentified endoscopy-associated outbreaks in Iran.

Reducing the environmental footprint of gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) Position Statement

Climate change and the destruction of ecosystems by human activities are among the greatest challenges of the 21st century and require urgent action. Health care activities significantly contribute to the emission of greenhouse gases and waste production, with gastrointestinal (GI) endoscopy being one of the largest contributors. This Position Statement aims to raise awareness of the ecological footprint of GI endoscopy and provides guidance to reduce its environmental impact. The European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) outline suggestions and recommendations for health care providers, patients, governments, and industry. MAIN STATEMENTS 1: GI endoscopy is a resource-intensive activity with a significant yet poorly assessed environmental impact. 2: ESGE-ESGENA recommend adopting immediate actions to reduce the environmental impact of GI endoscopy. 3: ESGE-ESGENA recommend adherence to guidelines and implementation of audit strategies on the appropriateness of GI endoscopy to avoid the environmental impact of unnecessary procedures. 4: ESGE-ESGENA recommend the embedding of reduce, reuse, and recycle programs in the GI endoscopy unit. 5: ESGE-ESGENA suggest that there is an urgent need to reassess and reduce the environmental and economic impact of single-use GI endoscopic devices. 6: ESGE-ESGENA suggest against routine use of single-use GI endoscopes. However, their use could be considered in highly selected patients on a case-by-case basis. 7: ESGE-ESGENA recommend inclusion of sustainability in the training curricula of GI endoscopy and as a quality domain. 8: ESGE-ESGENA recommend conducting high quality research to quantify and minimize the environmental impact of GI endoscopy. 9: ESGE-ESGENA recommend that GI endoscopy companies assess, disclose, and audit the environmental impact of their value chain. 10:  ESGE-ESGENA recommend that GI endoscopy should become a net-zero greenhouse gas emissions practice by 2050.

Assessment of postmanual cleaning adenosine triphosphate tests to prevent the use of contaminated duodenoscopes and linear echoendoscopes: the DETECT study

BACKGROUND AND AIMS

We investigated whether the use of postmanual cleaning adenosine triphosphate (ATP) tests lowers the number of duodenoscopes and linear echoendoscopes (DLEs) contaminated with gut flora.

METHODS

In this single-center before-and-after study, DLEs were ATP tested after cleaning. During the control period, participants were blinded to ATP results: ATP-positive DLEs were not recleaned. During the intervention period, ATP-positive DLEs were recleaned. DLEs underwent microbiologic sampling after high-level disinfection (HLD) with participants blinded to culture results.

RESULTS

Using 15 endoscopes of 5 different DLE types, we included 909 procedures (52% duodenoscopes, 48% linear echoendoscopes). During the intervention period, the absolute rate of contamination with gut flora was higher (16% vs 21%). The main analysis showed that contamination was less likely to occur in the intervention period (odds ratio, .32; 95% credible interval [CI], .12-.85). A secondary analysis showed that this effect was based on 1 particular duodenoscope type (estimated probability, 39% [95% CI, 18%-64%] vs 9% [95% CI, 2%-21%]), whereas no effect was seen in the other 4 DLE types. In detail, of the 4 duodenoscopes of this type, 2 had lower contamination rates (69% vs 39% and 36% vs 10%). During the control period, both these duodenoscopes had multiple episodes with ongoing contamination with the same microorganism that ended weeks before the start of the intervention period (ie, they were not terminated by ATP testing).

CONCLUSIONS

Postmanual cleaning ATP tests do not reduce post-HLD gut flora contamination rates of DLEs. Hence, postcleaning ATP tests are not suited as a means for quality control of endoscope reprocessing.

Early Versus Delayed Enteral Feeding in Predicted Severe Acute Gallstone Pancreatitis: A Retrospective Study

BACKGROUND

The optimal timing of enteral nutrition (EN) initiation in predicted severe acute gallstone pancreatitis (SAGP) and its influence on disease outcomes are not well known.

METHODS

We conducted a retrospective study of patients with predicted SAGP treated with endoscopic retrograde cholangiopancreatography and EN. The patients were classified into two groups according to the timing of EN initiation after admission: within 48 h, and more than 48 h. The primary outcome was in-hospital mortality. The secondary outcomes were length of hospital stay, need for intensive care admission, need for surgical intervention, improvements in blood test results after 7-10 days of EN, incidence of pancreatic necrosis and infection, and hospital care costs. The microbiological profiles of infectious complications were also evaluated.

RESULTS

Of the 98 patients, 31 and 67 started EN within 48 h, and more than 48 h after admission, respectively. Early EN was associated with a decrease in in-hospital mortality (0 vs. 11.9%; p=0.045), length of hospital stay (median:18 vs. 27 days; p=0.001), need for intensive care admission (3.2% vs. 20.9%; p=0.032), and hospital care costs (median:9,289 vs. 13,518 US$; p=0.007), compared to delayed EN. Moreover, early EN for 7-10 days had more beneficial effects on blood test results than delayed EN, including total protein (p=0.03) and CRP (p=0.006) levels. However, the need for surgical intervention and incidence of pancreatic necrosis did not differ between the two groups. In our study, Gram-negative bacteria were the main responsible pathogens (50.5%). Infection with multidrug-resistant organisms (MDRO) was found in 19.4% of the patients. The most common MDRO was MDR Enterococcus faecium. Early EN was not superior in reducing incidence of infected pancreatic necrosis, bacteremia, polymicrobial infection, or MDROs.

CONCLUSIONS

In patients with predicted SAGP, early EN is associated with a decrease in in-hospital mortality, length of hospital stay, need of intensive care admission, and hospital care costs, compared to delayed EN. There are no significant benefits of early EN in reducing the rate of infection-related complications. Further studies with larger sample sizes are warranted.

Estimating the environmental impact of disposable endoscopic equipment and endoscopes

OBJECTIVE

Procedure-intense specialties, such as surgery or endoscopy, are a major contributor to the impact of the healthcare sector on the environment. We aimed to measure the amount of waste generated during endoscopic procedures and to understand the impact on waste of changing from reusable to single use endoscopes in the USA.

DESIGN

We conducted a 5-day audit (cross-sectional study) of all endoscopies performed at two US academic medical centres with low and a high endoscopy volume (2000 and 13 000 procedures annually, respectively). We calculated the average disposable waste (excluding waste from reprocessing) generated during one endoscopic procedure to estimate waste of all endoscopic procedures generated in the USA annually (18 million). We further estimated the impact of changing from reusable to single-use endoscopes taking reprocessing waste into account.

RESULTS

278 endoscopies were performed for 243 patients. Each endoscopy generated 2.1 kg of disposable waste (46 L volume). 64% of waste was going to the landfill, 28% represented biohazard waste and 9% was recycled. The estimated total waste generated during all endoscopic procedures performed in the USA annually would weigh 38 000 metric tons (equivalent of 25 000 passenger cars) and cover 117 soccer fields to 1 m depth. If all endoscopic procedures were performed with single-use endoscopes and accounting for reprocessing, the net waste mass would increase by 40%. Excluding waste from ancillary supplies, net waste generated from reprocessing and endoscope disposal would quadruple with only using single-use endoscopes.

CONCLUSION

This quantitative assessment of the environmental impact of endoscopic procedures highlights that a large amount of waste is generated from disposable instruments. Transitioning to single-use endoscopes may reduce reprocessing waste but would increase net waste.

Risk evaluation of duodenoscope-associated infections in the Netherlands calls for a heightened awareness of device-related infections: a systematic review

BACKGROUND

The risk of exogenous infections from endoscopic procedures is often cited as almost negligible (1 infection in 1.8 million procedures); however, this risk is based on older literature and does not seem to match the number of infectious outbreaks due to contaminated duodenoscopes reported after endoscopic retrograde cholangiopancreatography (ERCP). Using Dutch data, we aimed to estimate the minimum risk of duodenoscope-associated infection (DAI) and colonization (DAC) in patients undergoing ERCP.

METHODS

A systematic literature search identified all DAI outbreaks in the Netherlands reported between 2008 and 2019. Included cases were confirmed by molecular matching of patient and duodenoscope cultures. Risk ratios were calculated based on the total number of ERCPs performed during the study period.

RESULTS

Three outbreaks were reported and published between 2008 and 2018, including 21 confirmed DAI cases and 52 confirmed DAC cases. The estimated number of ERCPs performed during the same period was 181 209-227 006. The calculated minimum estimated DAI risk was approximately 0.01 % and the minimum estimated DAC risk was 0.023 %-0.029 %.

CONCLUSIONS

The estimated risk of DAI in Dutch ERCP practice was at least 180 times higher than previously published risk estimates. The actual risk is likely to be (much) higher due to underreporting of infections caused by multidrug-resistant organisms and sensitive bacteria. Greater awareness by healthcare personnel involved in endoscopy and endoscope cleaning is required, as well as innovative technical solutions to contain and ultimately eliminate DAIs.

Risk Factors for Multidrug-Resistant Gram-Negative Bacteria Carriage upon Admission to the Intensive Care Unit

Multidrug-resistant Gram-negative bacteria (MDR-GNB) are microorganisms that have acquired resistance to extended-spectrum antibacterials and constitute an emerging threat to public health. Although carriers are an important source of transmission in healthcare settings, data about risk factors for MDR-GNB carriage are limited. Therefore, we aimed to identify risk factors for MDR-GNB carriage upon intensive care unit (ICU) admission and to optimise screening strategies. We conducted a case-control study. Admissions of adult patients to the ICU of a 1000-bed hospital during a year were included. We collected sociodemographic, clinical and microbiological data and performed a multivariate logistic regression model. A total of 1342 patients resulted in 1476 episodes of ICU admission, 91 (6.2%) of whom harboured MDR-GNB (38.5% women; median age 63.9 years). The most frequently isolated pathogens were Escherichia coli (57%) and Klebsiella pneumoniae (16%). The most frequent resistance mechanism was production of extended-spectrum beta lactamases. MDR-GNB carriage was associated to liver cirrhosis (OR 6.54, 95% CI 2.17-19.17), previous MDR-GNB carriage (OR 5.34, 1.55-16.60), digestive surgery (OR 2.83, 1.29-5.89) and length of hospital stay (OR 1.01 per day, 1.00-1.03). Several risk factors for MDR-GNB carriage upon admission to a high-risk setting were identified; the main comorbidity was liver cirrhosis.

Investigation of possible transmission of a susceptible microorganism through a contaminated duodenoscope; a case report

BACKGROUND

Despite compliance to extensive reprocessing protocols, duodenoscopes have been linked to outbreaks of susceptible and multi-drug resistant organisms (MDRO) due to persistent duodenoscope contamination. Duodenoscope-associated infections (DAIs) based on transmission of susceptible microorganisms are likely to be underreported due to detection bias.

CASE PRESENTATION

We describe the retrospective detection of a DAI case caused by a susceptible microorganism which at the time of clinical infection was not recognized as such. During 2017 and 2018, duodenoscopes were cultured on a daily basis due to research activities. While analyzing this data, it was found that a duodenoscope had been contaminated with Enterobacter cloacae complex over a period of 3 months. We checked whether patients treated with this duodenoscope had developed infections and found one patient with an E. cloacae cholangitis 3 months after the ERCP (Endoscopic retrograde cholangiopancreaticography) procedure. The isolates on the duodenoscope and in the patients' blood culture were indistinguishable by amplified fragment length polymorphism (AFLP). By classical multi-locus sequence typing (MLST), both strains were of the same (but novel) sequence type. Application of whole genome MLST showed 93 (out of 3757) allelic differences.

CONCLUSION

This case report describes a plausible link between a contaminated duodenoscope and a patient infection with E. cloacae. Transmission of susceptible E. cloacae was highly suspected from AFLP and MLST results; by WGS, 93 allelic differences were found which proves closely related strains. This report shows that DAIs by susceptible microorganisms can be easily missed and therefore its true prevalence remains underscored.

Biofilm accumulation in new flexible gastroscope channels in clinical use

OBJECTIVE

Assess the accumulation of protein and biofilm on the inner surfaces of new flexible gastroscope (FG) channels after 30 and 60 days of patient use and full reprocessing.

DESIGN

Clinical use study of biofilm accumulation in FG channels.

SETTING

Endoscopy service of a public hospital.

METHODS

First, we tested an FG in clinical use before the implementation of a revised reprocessing protocol (phase 1 baseline; n = 1). After replacement of the channels by new ones and the implementation of the protocol, 3 FGs were tested after 30 days of clinical use (phase 2; n = 3) and 3 FGs were tested after 60 days of clinical use (phase 3; n = 3), and the same FGs were tested in phase 2 and 3. Their biopsy, air, water, and air/water junction channels were removed and subjected to protein testing (n = 21), bacteriological culture (n = 21), and scanning electron microscopy (SEM) (n = 28). Air-water junction channels fragments were subjected to SEM only.

RESULTS

For the FGs, the average number of uses and reprocessing cycles was 60 times. Extensive biofilm was detected in air, water, and air-water junction channels (n = 18 of 28). All channels (28 of 28) showed residual matter, and structural damage was identified in most of them (20 of 28). Residual protein was detected in the air and water channels of all FG evaluated (phases 1-3), except for 1 air channel from phase 2. Bacteria were recovered from 8 of 21 channels, most air or water channels.

CONCLUSIONS

The short time before damage and biofilm accumulation in the channels was evident and suggests that improving the endoscope design is necessary. Better reprocessing methods and channel maintenance are needed.

Microbiological Surveillance of Endoscopes in a Southern Italian Transplantation Hospital: A Retrospective Study from 2016 to 2019

Endoscopes are medical instruments that are used routinely in health structures. Due to their invasive nature and contact with many patients, they may cause hospital-acquired infections if not disinfected correctly. To ensure a high-level disinfection procedure or reprocessing, since the methods currently adopted in our institute are adequate, we evaluated retrospectively the presence of microorganisms in our endoscopes after reprocessing. Microbiological surveillance was performed from January 2016 to December 2019 in the instruments in use in our endoscopic room after reprocessing. In total, 35 endoscopes (3 duodenoscopes, 3 echoendoscopes, 12 bronchoscopes, 5 colonoscopes, and 12 gastroscopes) were evaluated for the presence of microorganisms, including multidrug-resistant pathogens and indicator microorganisms (IMOs). Our procedures were in agreement with an internal protocol based on Italian, international, and the Center for Disease Control and Prevention (CDC) recommendations. Of a total of 811 samples, 799 (98.5%) complied with the regulatory guidelines, while 9 (1.1%) were positive for IMOs, and 3 (0.4%) displayed more than 10 colony-forming units (CFU) of environmental and commensal pathogens. Our results show that the internal reprocessing protocol is very efficient, leading to a very low number of observed contaminations, and it could be easily implemented by other health facilities that face a huge number of hospital-acquired infections due to incorrectly disinfected endoscopes.

Guidelines for Robotic Flexible Endoscopy at the Time of COVID-19

Flexible endoscopy involves the insertion of a long narrow flexible tube into the body for diagnostic and therapeutic procedures. In the gastrointestinal (GI) tract, flexible endoscopy plays a major role in cancer screening, surveillance, and treatment programs. As a result of gas insufflation during the procedure, both upper and lower GI endoscopy procedures have been classified as aerosol generating by the guidelines issued by the respective societies during the COVID-19 pandemic-although no quantifiable data on aerosol generation currently exists. Due to the risk of COVID-19 transmission to healthcare workers, most societies halted non-emergency and diagnostic procedures during the lockdown. The long-term implications of stoppage in cancer diagnoses and treatment is predicted to lead to a large increase in preventable deaths. Robotics may play a major role in this field by allowing healthcare operators to control the flexible endoscope from a safe distance and pave a path for protecting healthcare workers through minimizing the risk of virus transmission without reducing diagnostic and therapeutic capacities. This review focuses on the needs and challenges associated with the design of robotic flexible endoscopes for use during a pandemic. The authors propose that a few minor changes to existing platforms or considerations for platforms in development could lead to significant benefits for use during infection control scenarios.

Outer Membrane Vesicles Released From Aeromonas Strains Are Involved in the Biofilm Formation

Aeromonas spp. are Gram-negative rod-shaped bacteria ubiquitously distributed in diverse water sources. Several Aeromonas spp. are known as human and fish pathogens. Recently, attention has been focused on the relationship between bacterial biofilm formation and pathogenicity or drug resistance. However, there have been few reports on biofilm formation by Aeromonas. This study is the first to examine the in vitro formation and components of the biofilm of several Aeromonas clinical and environmental strains. A biofilm formation assay using 1% crystal violet on a polystyrene plate revealed that most Aeromonas strains used in this study formed biofilms but one strain did not. Analysis of the basic components contained in the biofilms formed by Aeromonas strains confirmed that they contained polysaccharides containing GlcNAc, extracellular nucleic acids, and proteins, as previously reported for the biofilms of other bacterial species. Among these components, we focused on several proteins fractionated by SDS-PAGE and determined their amino acid sequences. The results showed that some proteins existing in the Aeromonas biofilms have amino acid sequences homologous to functional proteins present in the outer membrane of Gram-negative bacteria. This result suggests that outer membrane components may affect the biofilm formation of Aeromonas strains. It is known that Gram-negative bacteria often release extracellular membrane vesicles from the outer membrane, so we think that the outer membrane-derived proteins found in the Aeromonas biofilms may be derived from such membrane vesicles. To examine this idea, we next investigated the ability of Aeromonas strains to form outer membrane vesicles (OMVs). Electron microscopic analysis revealed that most Aeromonas strains released OMVs outside the cells. Finally, we purified OMVs from several Aeromonas strains and examined their effect on the biofilm formation. We found that the addition of OMVs dose-dependently promoted biofilm formation, except for one strain that did not form biofilms. These results suggest that the OMVs released from the bacterial cells are closely related to the biofilm formation of Aeromonas strains.

Does double high-level disinfection for duodenoscopes add any value? A mini-systematic review and meta-analysis

Background

Duodenoscope-emerging infection especially drug-resistant bacteria is considered a major concern nowadays. Different approaches were attempted to overcome this problem, like double high-level disinfection procedure. We performed a systematic review and meta-analysis to evaluate risk difference for positive cultures from duodenoscopes between double high-level disinfection (dHLD) and single (standard) high-level disinfection (sHLD).

Main body

A thorough literature search (in October and November 2019) for studies comparing dHLD and sHLD for duodenoscopes was performed by 3 researchers in the Web of Science, Scopus, PubMed, and Cochran databases. The search terms were “duodenoscope,” “ERCP endoscope,” “disinfection,” “sterilization,” and “reprocessing,” and only randomized clinical trials with the English language were accepted.

Four trials were identified studying dHLD, and only 2 clinical trials comparing dHLD with standard sHLD were found reporting 6193 duodenoscope cultures. Overall sHLD cultures were 2972, and dHLD cultures were 3221; overall positive cultures were 140 in sHLD and 161 in dHLD.

The results of a meta-analysis using the random-effect model showed no significant risk difference (RD) between the 2 procedures for duodenoscope positive cultures (p = 0.53, RD 0.003, 95% CI “− 0.007–0.013”).

Conclusions

Double HLD offered no significant difference over single HLD for duodenoscope disinfection. An alternative strategy to overcome duodenoscope-transmitted infection is a big issue to be resolved.

Endoscopic Management of Pancreaticobiliary Disease

The evolution of advanced pancreaticobiliary endoscopy in the past 50 years is remarkable. Endoscopic retrograde cholangiopancreatography (ERCP) has progressed from a diagnostic test to an almost entirely therapeutic procedure. The endoscopist must have a clear understanding of the indications for ERCP to avoid unnecessary complications, including post-ERCP pancreatitis. Endoscopic ultrasound initially was used as a diagnostic tool but now is equipped with accessary channels allowing endoscopic ultrasound-guided interventions in various pancreaticobiliary conditions. This review discusses the endoscopic management of common pancreatic and biliary diseases along with the techniques, indications, outcomes, and complications of pancreaticobiliary endoscopy.

Antifogging/Antibacterial Coatings Constructed by N-Hydroxyethylacrylamide and Quaternary Ammonium-Containing Copolymers

Endoscopic surgery has gained widespread applications in various clinical departments, and endoscope surfaces with antifogging and antibacterial properties are essential for elaborate procedures. In this work, novel antifogging/antibacterial coatings were developed from a cationic copolymer and a hydrophilic copolymer, polyhedral oligomeric silsesquioxane-poly(quaternary ammonium compound-co-2-aminoethyl methacrylate hydrochloride) [POSS-P(QAC-co-AEMA)] and poly(N-hydroxyethylacrylamide-co-glycidyl methacrylate) [P(HEAA-co-GMA)] via a facile and green blending method. Such transparent coatings showed excellent antifogging performance under both in vitro and in vivo fogging conditions, mainly attributed to the high water-absorbing capability of HEAA and QAC. Antibacterial assays proved that the blending coatings had a superior antibacterial property, which could be improved with the proportion of POSS-P(QAC-co-AEMA) because of the bactericidal efficiency of cationic QAC. Meanwhile, owing to the high hydratability of HEAA, the blending coatings exhibited a bacteria-repelling property. By simply tuning the blending ratio of POSS-P(QAC-co-AEMA) and P(HEAA-co-GMA), the comprehensive bacteria-killing and bacteria-repelling properties of the coatings were achieved. Moreover, after incubating with red blood cells, the prepared blending coatings presented a lower hemolytic rate of less than 5%. The findings provided a potential means for addressing the challenge of fogging and bacterial contamination occurring in endoscopic lenses and other medical devices.