Transmission of infection by flexible gastrointestinal endoscopy and bronchoscopy. Clin Microbiol Rev. 2013;26:231-254. [PMID: 23554415 DOI: 10.1128/cmr.00085-12]

An Analysis of the Contaminants on Otoscopes of Otolaryngology Residents: An Observational Study

The study was conducted to learn if the otoscope, a noncritical medical device, used by ENT residents harbor pathogenic organism. This study was conducted in a medical teaching hospital in India. Total of 38 otoscopes of ENT residents were examined after taking samples using sterile cotton swabs from otoscope speculum and otoscope head and both bacterial and fungal culture were studied. The study showed that 11 otoscope heads (28.94%) and 11 otoscope speculums (28.94%) out of the 38 otoscopes studied showed bacterial growth. Most commonly isolated bacteria were skin commensals followed by Klebsiella species. Fungal growth was seen in 3 out of 38 otoscope Speculums (7.89%). All 3 fungi isolated during the study belonged to Aspergillus species. Training residents regarding hygiene of medical equipments is necessary. Residents must be periodically assessed regarding their practice in handling medical equipments.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-024-04695-8.

Whole-genome sequencing establishes persistence of biofilm-associated Pseudomonas aeruginosa detected from microbiological surveillance of gastrointestinal endoscopes

BACKGROUND

An increased incidence of P. aeruginosa in microbiological surveillance (MS) cultures from gastrointestinal endoscopes was detected between March 2020 to March 2023 in Tan Tock Seng Hospital Singapore. The aim of this report is to describe the use of whole-genome sequencing (WGS) in this investigation.

METHODS

WGS was performed for all P. aeruginosa isolates with pairwise comparison of isolates to assess for genomic linkage. Comprehensive review of reprocessing practices and environmental sampling was performed.

FINDINGS

Twenty-two P. aeruginosa isolates were detected from endoscopic MS cultures. Fifteen (68%) isolates were available for WGS. Eighteen pairwise comparisons of isolates were made, of which 10 were found to be genomically linked. One endoscope had P. aeruginosa repeatedly cultured from subsequent MS that were genomically linked and persistent despite repeat endoscopic reprocessing, establishing the persistence of biofilm that could not be eradicated with routine reprocessing. All P. aeruginosa isolates cultured from other different endoscopes were genetically distinct. Investigation into reprocessing practices revealed the use of air/water valves connected to endoscopes during clinical use. Inspection of these valves revealed the presences of cracks and tears. All other environmental samples were negative.

CONCLUSIONS

The WGS findings helped to deprioritize common source contamination and supported the hypothesis of biofilm buildup within endoscopes leading to repeatedly positive MS cultures that were genomically linked. This was possibly related to incomplete reprocessing of the damaged air/water valves, resulting in biofilm build up. All faulty valves were changed and subsequently cleaned separately with ultrasonic cleaning followed by sterilization which resolved this incident.

Enhancing Pathogen Detection in Implant-Related Infections through Chemical Antibiofilm Strategies: A Comprehensive Review

Implant-related infections (IRIs) represent a significant challenge to modern surgery. The occurrence of these infections is due to the ability of pathogens to aggregate and form biofilms, which presents a challenge to both the diagnosis and subsequent treatment of the infection. Biofilms provide pathogens with protection from the host immune response and antibiotics, making detection difficult and complicating both single-stage and two-stage revision procedures. This narrative review examines advanced chemical antibiofilm techniques with the aim of improving the detection and identification of pathogens in IRIs. The articles included in this review were selected from databases such as PubMed, Scopus, MDPI and SpringerLink, which focus on recent studies evaluating the efficacy and enhanced accuracy of microbiological sampling and culture following the use of chemical antibiofilm. Although promising results have been achieved with the successful application of some antibiofilm chemical pre-treatment methods, mainly in orthopedics and in cardiovascular surgery, further research is required to optimize and expand their routine use in the clinical setting. This is necessary to ensure their safety, efficacy and integration into diagnostic protocols. Future studies should focus on standardizing these techniques and evaluating their effectiveness in large-scale clinical trials. This review emphasizes the importance of interdisciplinary collaboration in developing reliable diagnostic tools and highlights the need for innovative approaches to improve outcomes for patients undergoing both single-stage and two-stage revision surgery for implant-related infections.

Complications Associated with AMBU™ Scope Use: An FDA MAUDE Analysis

Ambu® aScope™ is a disposable flexible videoscope used for a wide range of medical procedures. However, adverse events associated with this device can occur. The Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database was explored for patient-related adverse events associated with Ambu® aScope™ use between January 1, 2000 and December 15, 2023. Search terms included "Ambu" and "Ascope." Thirty unique adverse events were identified. Twenty-one of the events were associated with patient injury, and 9 with device malfunction. Eight patient-reported problems were documented as foreign bodies, 3 events as airway obstruction, desaturation, or hypoxic events, and 1 event as anxiety/cardiac arrest. The remaining 18 reported insufficient information other than associated with patient injury. We found that Ambu® aScope™ flexible nasolaryngoscopes and bronchoscopes are a common and effective tool for airway evaluations that may infrequently serve as a rare form of foreign body with potentially life-threatening consequences.

Fluid retention in endoscopes: A real-world study on drying effectiveness

BACKGROUND

Outbreaks linked to inadequate endoscope drying have infected numerous patients, and current standards and guidelines recommend at least 10 minutes of forced air for drying channels. This study evaluated a new forced-air drying system (FADS) for endoscopes.

METHODS

Drying was assessed using droplet detection cards; visual inspection of air/water connectors, suction connectors, and distal ends; and borescope examinations of endoscope interiors. Assessments were performed after automated endoscope reprocessor (AER) alcohol flush and air purge cycles and after 10-minute FADS cycles.

RESULTS

Researchers evaluated drying during encounters with 22 gastroscopes and 20 colonoscopes. After default AER alcohol and air purge cycles, 100% (42/42) of endoscopes were still wet. Substantial fluid emerged from distal ends during the first 15 seconds of the FADS cycle, and droplets also emerged from air/water and suction connectors. Following FADS cycle completion, 100% (42/42) were dry, with no retained fluid detected by any of the assessment methods.

CONCLUSIONS

Multiple endoscope ports and channels remained wet after AER cycles intended to aid in drying but were dry after the FADS cycle. This study reinforced the need to evaluate the effectiveness of current drying practices and illustrated the use of practical tools in a real-world setting.

Assessment of the Learning Curve for a Single-Use Disposable Duodenoscope

BACKGROUND AND AIMS

In response to documented duodenoscope-related infectious outbreaks of multidrug-resistant organisms, the Food and Drug Administration has recommended a transition to duodenoscopes with innovative designs, including duodenoscopes with disposable components or fully disposable duodenoscopes. We aim to characterize the learning curve (LC) for a single-use disposable duodenoscope.

METHODS

We performed a retrospective analysis of a prospectively collected database from 31 patients who underwent ERCP by a single, experienced operator using the EXALT Model D® (Boston Scientific, Marlborough) disposable duodenoscope at a single tertiary referral center. The LC for this device was described by the number of cases needed to achieve proficiency using cumulative sum (CUSUM) analysis. Number of attempts to cannulate and time to cannulate the desired duct were assessed as separate endpoints. The overall mean number of attempts and overall mean time to cannulation were used as the target values in the respective CUSUM analyses. Proficiency was defined as the number of procedures where an inflection point was reached in the CUSUM graph. This observation indicates improving operator performance as shown by a decrease in the number of attempts and shortening of cannulation time after the defined number of procedures.

RESULTS

Overall, 31 patients underwent ERCP using the EXALT Model D disposable duodenoscope by a single experienced endoscopist. 6 (19%) patients had a native papilla and the majority of these procedures were classified as ASGE complexity level 2 or above. The procedure was completed using solely the disposable duodenoscope in 27 patients (87%), while a reusable duodenoscope was required for procedure completion in 4 patients (13%). The cross-overs were distributed evenly across the performance period. Procedure-related adverse events included: post-ERCP pancreatitis (3%), bleeding (3%) and no perforations. In the analyses of both endpoints, an inflection of the CUSUM curves is achieved at 10 cases, indicating sustained reduction of cannulation attempts and time to cannulation.

CONCLUSION

Among experienced pancreaticobiliary endoscopists, approximately 10 ERCPs is the threshold whereby procedure-related factors including cannulation success and procedural time improves. Procedure-related adverse events are consistent with those expected with reusable duodenoscopes. The need to cross-over from single-use duodenoscope to reusable duodenoscope did not appear to be related to the learning curve, as they were evenly distributed across the study period. These results can be used to guide adoption of single-use duodenoscopes into clinical practice.

Factors associated with irritable bowel syndrome and Helicobacter pylori infection: public knowledge and awareness of signs and symptoms

OBJECTIVE

To investigate factors related to the risk of developing irritable bowel syndrome (IBS) or Helicobacter pylori infection.

METHODS

This cross-sectional, questionnaire-based study analysed the responses from participants that completed an online questionnaire, which asked about their knowledge of the causes and risk factors associated with IBS and H. pylori infection.

RESULTS

The study analysed responses from 230 participants: 181 females (of 227 participants; 79.7%) and 190 aged 18-40 years (of 228; 83.3%). Of the 230 participants, 40 (17.4%) had been diagnosed by a physician with IBS and 57 (24.8%) had been diagnosed with H. pylori infection. Of 226 participants, 93 (41.2%) had self-medicated with antibiotics in the past 6 months for various reasons. The overall mean ± SD knowledge score about IBS and H. pylori infection for the study cohort (n = 230) was 35.8 ± 19.2%. Wald χ2-test analysis demonstrated that chronic diseases, antibiotic use and having an endoscopy were significantly associated with developing IBS. Male sex and chronic diseases were significantly associated with H. pylori infection. Logistic regression analysis showed no relationship between IBS and H. Pylori infection.

CONCLUSION

Chronic diseases was the only risk factor common for IBS and H. pylori infection.

A search strategy for detecting duodenoscope-associated infections: a retrospective observational study

BACKGROUND

Duodenoscope-associated infections (DAIs) are exogenous infections resulting from the use of contaminated duodenoscopes. Though numerous outbreaks of DAI have involved multidrug-resistant micro-organisms (MDROs), outbreaks involving non-MDROs are also likely to occur. Detection challenges arise as these infections often resolve before culture or because causative strains are not retained for comparison with duodenoscope strains.

AIM

To identify and analyse DAIs spanning a seven-year period in a tertiary care medical centre.

METHODS

This was a retrospective observational study. Duodenoscope cultures positive for gastrointestinal flora between March 2015 and September 2022 were paired with duodenoscope usage data to identify patients exposed to contaminated duodenoscopes. Analysis encompassed patients treated after a positive duodenoscope culture and those treated within the interval from a negative to a positive culture. Patient identification numbers were cross-referenced with a clinical culture database to identify patients developing infections with matching micro-organisms within one year of their procedure. A 'pair' was established upon a species-level match between duodenoscope and patient cultures. Pairs were further analysed via antibiogram comparison, and by whole-genome sequencing (WGS) to determine genetic relatedness.

FINDINGS

Sixty-eight pairs were identified; of these, 21 exhibited matching antibiograms which underwent WGS, uncovering two genetically closely related pairs categorized as DAIs. Infection onset occurred up to two months post procedure. Both causative agents were non-MDROs.

CONCLUSION

This study provides crucial insights into DAIs caused by non-MDROs and it highlights the challenge of DAI recognition in daily practice. Importantly, the delayed manifestation of the described DAIs suggests a current underestimation of DAI risk.

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.

A proposed cleaning classification system for reusable medical devices to complement the Spaulding classification

A central tenet in infection prevention is application of the Spaulding classification system for the safe use of medical devices. Initially defined in the 1950s, this system defines devices and surfaces as being critical, semi-critical or non-critical depending on how they will be used on a patient. Different levels of antimicrobial treatment, defined as various levels of disinfection or sterilization, are deemed appropriate to reduce patient risk of infection. However, a focus on microbial inactivation is insufficient to address this concern, which has been particularly highlighted in routine healthcare facility practices, emphasizing the underappreciated importance of cleaning and achieving acceptable levels of cleanliness. A deeper understanding of microbiology has evolved since the 1950s, which has led to re-evaluation of the Spaulding classification along with a commensurate emphasis on achieving appropriate cleaning. Albeit underappreciated, cleaning has always been important as the presence of residual materials on surfaces can interfere with the efficacy of the antimicrobial process to inactivate micro-organisms, as well as other risks to patients including device damage, malfunction and biocompatibility concerns. Unfortunately, this continues to be relevant, as attested by reports in the literature on the occurrence of device-related infections and outbreaks due to failures in processing expectations. This reflects, in part, increasing sophistication in device features and reuse, along with commensurate manufacturer's instructions for use. Consequently, this constitutes the first description and recommendation of a new cleaning classification system to complement use of the traditional Spaulding definitions to help address these modern-day technical and patient risk challenges. This quantitative risk-based classification system highlights the challenge of efficient cleaning based on the complexity of device features present, as an isolated variable impacting cleaning. This cleaning classification can be used in combination with the Spaulding classification to improve communication of cleaning risk of a reusable medical device between manufacturers and healthcare facilities, and improve established cleaning practices. This new cleaning classification system will also inform future creation, design thinking and commensurate innovations for the sustainable safe reuse of important medical devices.

Comparing the Effects of Two Culture Methods to Determine the Total Heterotrophic Bacterial Colony Count in Hospital Purified Water

BACKGROUND

Accurately detecting the quantity of microorganisms in hospital purified water is of significant importance for early identification of microbial contamination and reducing the occurrence of water-borne hospital infections. The choice of detection method is a prerequisite for ensuring accurate results. Traditional Plate Count Agar (PCA) belongs to a high-nutrient medium, and there may be limitations in terms of accuracy or sensitivity in detecting microorganisms in hospital purified water. On the other hand, Reasoner's 2A agar (R2A) has characteristics, such as low-nutrient levels, low cultivation temperature, and extended incubation time, providing advantages in promoting the growth of aquatic microorganisms. This study, through comparing the differences in total colony counts between two detection methods, aims to select the method more suitable for the growth of aquatic microorganisms, offering new practical insights for accurately detecting the total count of heterotrophic bacteria in hospital purified water.

METHODS

The most commonly used plate count agar (PCA) method, and the R2A agar culture were adopted to detect microorganisms and determine the total number of bacterial colonies in the water for oral diagnosis and treatment water and terminal rinse water for endoscopes in medical institutions. The two water samples were inoculated by pour plate and membrane filtration methods, respectively. Using statistical methods including Spearman and Pearson correlation, Wilcoxon signed-rank sum test, paired-Chi-square test, and linear regression, we analyze the differences and associations in the bacterial counts cultivated through two different methods.

RESULTS

In 142 specimens of the water, the median and interquartile range of the heterotrophic bacterial colony number under the R2A culture method and under the PCA culture method were 200 (Q1-Q3: 25-18,000) and 6 (Q1-Q3: 0-3700). The total number of heterotrophic bacteria colonies cultured in R2A medium for 7 days was more than that cultured in PCA medium for 2 days (P < 0.05). The linear regression results showed a relatively strong linear correlation between the number of colonies cultured by the R2A method and that cultured by the PCA method (R2 = 0.7264). The number of bacterial species detected on R2A agar medium is greater than that on PCA agar medium.

CONCLUSION

The R2A culture method can better reflect the actual number of heterotrophic bacterial colonies in hospital purified water. After logarithmic transformation, the number of colonies cultured by the two methods showed a linear correlation.

Design, simulation and experimental analysis of a monolithic bending section for enhanced maneuverability of single use laparoscopic devices

Standard laparoscopes, which are widely used in minimally invasive surgery, have significant handling limitations due to their rigid design. This paper presents an approach for a bending section for laparoscopes based on a standard semi-finished tube made of Nitinol with laser-cut flexure hinges. Flexure hinges simply created from a semi-finished product are a key element for realizing low-cost compliant structures with minimal design space. Superelastic materials such as Nitinol allow the reversible strain required for this purpose while maintaining sufficient strength in abuse load cases. This paper focuses on the development of a bending section for single use laparoscopic devices (OD 10 mm) with a bending angle of 100°, which enables the application of 100 µm diameter Nitinol actuator wires. For this purpose, constructive measures to realise a required bending curvature and Finite Element Analysis for determining the strain distribution in the flexural region are applied and described for the design of the flexure hinges. In parallel, the influence of the laser-based manufacturing process on the microstructure is investigated and evaluated using micrographs. The deformation behavior of the bending section is experimentally determined using Digital Image Correlation. The required actuation forces and the failure load of the monolithic bending section is measured and compared to a state of the art riveted bending section made of stainless steel. With the developed monolothic bending section the actuation force could be reduced by 50% and the available inner diameter could be increased by 10% while avoiding the need of any assembly step.

International Delphi Consensus Study on disposable single-use endoscopy: A path to clinical adoption

BACKGROUND/OBJECTIVE

Increasing infectious rate estimates and low microbiological surveillance affect safety of gastrointestinal endoscopy globally. Single use endoscopes and accessories have been claimed to improve safety, but there is lack of data on their indication and sustainability. We aimed to identify a series of best practice recommendations for the use of single use endoscopes and accessories using a modified Delphi.

METHODS/DESIGN

Consensus statements for the use of single use endoscopy and accessories were developed using a modified Delphi process, utilizing an international endoscopist expert panel of 62 experts from 33 nations. The main steps in the process were selecting the consensus group, conducting systematic literature reviews, developing statements, and anonymous voting on the statements until consensus was reached. High-risk patients were defined as those with multi-drug-resistant infections, immunosuppressive medication or chemotherapy, post-transplantation, or with severe neutropenia.

RESULTS

Of the 26 statements that were voted upon through two rounds, 17 statements reached consensus. Category 1: single use accessories (8 statements), related to defining recommendations for the use of single use accessories in all patient populations or high-risk patients. Category 2: clinical indication for single use endoscopes (9 statements), including indications to high-risk patients, protecting the endoscope apparatus and contamination measures in endoscopy units. Category 3: technical factors (4 statements), related to superior performance and technical specifications with the new innovation. Category 4: environmental issues (2 statements), concerning mechanisms that reduce the detrimental burden to the environment. Category 5: financial implications (3 statements), related to healthcare policies, cost neutrality and other financial associations of single use endoscopy.

CONCLUSIONS

This is the first international initiative in determining clinical indications for single use endoscopy and accessories. The study's findings should serve as a framework for future physicians to guide future research and aid the proper evidence-based indications for the implementation of single use endoscopes in clinical practice.

Bronchial Tree System Analysis of Live Beluga Whale (Delphinapterus leucas) Using Bronchoscopy

Cetaceans, including beluga whales (Delphinapterus leucas), have high morbidity and mortality rates due to bacterial or fungal lower respiratory infections. Bronchoalveolar lavage fluid (BALF) collection by bronchoscopy is beneficial for detecting pathogenic microorganisms in the lower respiratory tract. Efficient and safe bronchoscopy requires characterizing the bronchial tree systems of beluga whales, as no reports exist on bronchial length and bifurcation. In this study, bronchoscopy was performed on five captive beluga whales (9-44 years old) to detect bronchial length and bifurcation. The lengths from the blowhole to the scope impassable points due to the minimized bronchi diameters of the left principal bronchus (LPB), right principal bronchus (RPB), and tracheal bronchus (TB) were 110-155, 110-150, and 80-110 cm, respectively, and were correlated with the body length. Bronchoscopy identified more than 10, 10, and 6 bifurcated bronchi from the LPB, RPB, and TB, respectively. This is the first report to clarify the differences in bronchial tree systems between beluga whales and other cetaceans, as well as the differences for each individual beluga whale. These results could be useful for obtaining BALF via bronchoscopy to detect pathogenic microorganisms causing infections in the lower respiratory tract of beluga whales.

Point of Use Treatment for Medical Devices: From Bedside to Battlefield

INTRODUCTION

Point of use (POU) treatment is a critical first step of medical device reprocessing. Reusable instruments and flexible endoscopes require a minimum of terminal sterilization or high-level disinfection, neither of which can be guaranteed if POU is performed incorrectly. Compliance considerations for POU include hospital accreditation readiness, unique austere surgical mission requirements, and the transition of future conflict towards Large Scale Combat Operations. This integrative review aims to describe POU for reusable instruments and endoscopes, and extrapolate implications for Military Health System policies and future considerations.

MATERIALS AND METHODS

The authors performed an integrative review and comprehensive literature search in PubMed and CINAHL with the keywords "point of use," "point of use cleaning," "POU," "instrument," "high-level disinfection," "endoscope," and "clean." Articles were limited to "English" and "human" from 2017 to 2023. The authors also performed a thorough review of the Defense Health Agency and service-specific doctrine, as well as national guidelines regarding POU adherence.

RESULTS

The literature review yielded 18 articles that discussed the transport and reprocessing of reusable medical devices. Regulatory standards and national guidelines were used to supplement the literature. Seventeen evidence-based criteria were extrapolated from the literature to generate two step-by-step guides for the POU treatment of endoscopes and reusable instruments (Tables I and II). Despite increased morbidity and mortality rates linked to inadequate device reprocessing, compliance with POU procedures remains low. Barriers to practice included complex POU processes, intricately designed surgical instruments and endoscopes, lack of healthcare worker (HCW) knowledge and competency, and inadequate or ambiguously written policies. Training, competency assessments, and clearly written policies and procedures can be cost-effective, evidence-based, and feasible solutions.

CONCLUSION

Completing POU treatment is critical to a successful surgical mission in both the hospital and austere environment. Implications to practice include implementing evidence-based POU programs that improve patient outcomes and readiness while decreasing costs.

Feasibility and efficacy of newly developed eco-friendly, automatic washer for endoscope using electrolyzed alkaline and acidic water

INTRODUCTION

As well as preventing nosocomial and healthcare-associated infections, a reliable and eco-friendly washer for medical equipment would also be safe for the global environment. The aim of this study was to evaluate the efficacy of a newly developed automatic washing system (Nano-washer) that uses electrolyzed water and ultrasonication without detergent for washing endoscopes.

METHODS

Patients who underwent laparoscopic lobectomy or laparoscopic colectomy at Nagasaki University between 2018 and 2022 were included. A total of 60 cases of endoscope use were collected and classified according to endoscope washing method into the Nano-washer group (using no detergent) (n = 40) and the manual washing group (n = 20). Protein and bacterial residues were measured before and after washing, using absorbance spectrometry and 16S rRNA polymerase chain reaction. The effectiveness of protein and bacterial removal and endoscope surface damage after washing were compared under specular vision between the groups.

RESULTS

Nano-washer did not use detergent unlike manual washing. There was no difference in demographic or clinical characteristics between the groups except for the presence of comorbidities in the lobectomy group (Nano-washer, 85%; manual washing, 40%, P = .031). Compared with the manual washing group, residual protein levels in the Nano-washer group were significantly reduced after washing (lobectomy, 0.956 mg/mL vs 0.016 mg/mL, P < .001; colectomy, 0.144 mg/mL vs 0.002 mg/mL, P = .008). Nano-washer group showed a significant reduction in bacteria between before and after lobectomy (9437 copies/cm2 vs 4612 copies/cm2 , P = .024).

CONCLUSION

Nano-washer is a promising, effective, and eco-friendly automatic washing device that is safer and more efficient than manual washing.

Effect of a disposable endoscope precleaning kit in the cleaning procedure of gastrointestinal endoscope: A multi-center observational study

BACKGROUND

Precleaning is a key step in endoscopic reprocessing.

AIM

To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.

METHODS

Altogether, 228 used gastrointestinal endoscopes were selected from five high-volume endoscopy units and precleaned by a traditional precleaning bucket (group T) or a disposable endoscope bedside precleaning kit (group D). Each group was further subdivided based on the replacement frequency of the cleaning solution, which was replaced every time in subgroups T1 and D1 and every several times in subgroups Ts and Ds. The adenosine triphosphate (ATP) level and residual proteins were measured three times: Before and after precleaning and after manual cleaning.

RESULTS

After precleaning, the precleaning kit significantly reduced the ATP levels (P = 0.034) and has a more stable ATP clearance rate than the traditional precleaning bucket. The precleaning kit also saved a quarter of the cost of enzymatic detergent used during the precleaning process. After manual cleaning, the ATP levels were also significantly lower in the precleaning kit group than in the traditional precleaning bucket group (P < 0.05). Meanwhile, the number of uses of the cleaning solution (up to four times) has no significant impact on the cleaning effect (P > 0.05).

CONCLUSION

Considering its economic cost and cleaning effect, the use of a disposable endoscope bedside precleaning kit can be an optimal option in the precleaning stage with the cleaning solution being replaced several times in the manual cleaning stage.

A bronchoscopy-associated pseudo-outbreak of Mycobacterium chelonae and Mycobacterium mucogenicum associated with contaminated ice machine water and ice

A pseudo-outbreak of bronchoscopy-associated Mycobacterium chelonae and M. mucogenicum was traced to contaminated ice machine water and ice. A nonsterile ice bath was used to cool uncapped, sterile, saline syringes used to slow procedural bleeding. Joining the growing evidence of bronchoscopy pseudo-outbreaks, our investigation describes several lessons for future prevention.

Microbiological characteristics, transmission routes, and mitigation measures in bronchoscope-associated investigations: Summary of Centers for Disease Control and Prevention (CDC) consultations, 2014-2022

In this summary of US Centers for Disease Control and Prevention (CDC) consultations with state and local health departments concerning their bronchoscope-associated investigations from 2014 through 2022, bronchoscope reprocessing gaps and exposure to nonsterile water sources appeared to be the major routes of transmission of infectious pathogens, which were primarily water-associated bacteria.

What Are the Ready-to-Use Endoscope Channels Hiding?: Unraveling the Risks of Safe Reuse

Contamination due to failures or omissions in the reprocessing steps of gastrointestinal endoscopes is common in clinical practice. Ensuring the proper execution of each step is a challenge for reprocessing personnel. This cross-sectional study was conducted in an endoscopy setting between March and May 2021. We performed interviews about reprocessing practices, analyzed the life history of the equipment, and performed inspections through a borescope video of gastrointestinal endoscope channels that were stored and ready for use. A borescope is a complementary tool used to validate endoscope reprocessing, evaluate the internal visualization of channels, and identify changes that can compromise the safety of its use, which are often not detected in the leak test. Thirteen biopsy channels from stored gastrointestinal endoscopes were inspected. We found that 85% had stains and grooves, 69% contained moisture, and 46% had debris. There was at least one noncompliance issue in all of the channels inspected.

Reprocessing semicritical items: An overview and an update on the shift from HLD to sterilization for endoscopes

BACKGROUND

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (e.g., gastrointestinal endoscopes, endocavitary probes). Such medical devices require minimally high-level disinfection.

METHODS

Analyze the methods used to reprocess semicritical medical devices and identify methods and new technologies to reduce the risk of infection.

RESULTS

The reprocessing methods for semicritical medical devices is described as well as a shift from high-level disinfection to sterilization for lumened endoscopes.

CONCLUSIONS

Strict adherence to current guidelines and transition to sterilization for endoscopes is required as more outbreaks have been linked to inadequately disinfected endoscopes and other semicritical items than any other reusable medical devices.

In vitro activity of sanitizers against mono- and polymicrobial biofilms of C. parapsilosis and S. aureus

The emergence of disinfectant-resistant microorganisms poses a significant threat to public health. These resilient pathogens can survive and thrive in hospital settings despite routine disinfection practices, leading to persistent infections and the potential for outbreaks. In this study, we investigated the impact of 11 different commercial sanitizers at various concentrations and exposure times on biofilms consisting of clinical and nosocomial environmental isolates of Candida parapsilosis and Staphylococcus aureus. Among the sanitizers tested, 0.5% and 2.0% chlorhexidine (CLX), 10% polyvinyl pyrrolidone (PVP-I), a disinfectant based on quaternary ammonium compound (QAC), 2% glutaraldehyde, and 0.55% orthophthalaldehyde (OPA) demonstrated efficacy against both C. parapsilosis and S. aureus in monospecies and mixed biofilms. Analysis showed that 0.5% CLX and 10% PVP-I had fungicidal and bactericidal activity against all biofilms. However, the sanitizer based on QAC and 0.55% OPA proved to be bacteriostatic and fungicidal against both monospecies and mixed biofilms. In mixed biofilms, despite the last four sanitizers exerting fungicidal action, the reduction of fungal cells was approximately 4 log10 CFU/mL compared to monospecies biofilms, showing that the interaction provided more resistance of the yeast to the sanitizer. Formation of mixed biofilms in hospital settings can create an ecological niche that enhances the survival of pathogens against routine sanitization procedures. Therefore, effective sanitization practices, including regular cleaning with effective sanitizers, should be implemented to prevent C. parapsilosis/S. aureus biofilm formation in healthcare settings.

Evaluation of two detergent-disinfectants and a detergent on a Klebsiella pneumoniae biofilm formed within Tygon tubes

BACKGROUND

Transmission of infections via contaminated endoscopes is a common problem. Manual cleaning, using at least a detergent, is an important step in endoscope processing and should be performed as soon as possible to avoid drying of organic residues that might interfere with high-level disinfection and promote biofilm formation.

AIM

To assess the efficacy of two detergent-disinfectants, enzymatic and non-enzymatic, and of an enzymatic detergent used during the manual cleaning against a Klebsiella pneumoniae biofilm.

METHODS

A 24 h biofilm statically formed in a Tygon tube was exposed to detergent-disinfectants at 20 °C and 35 °C for 10 mn, and to enzymatic detergent at 45 °C for 60 mn. The logarithmic reduction in bacteria in the Tygon tube and the number of bacteria in the product supernatant were calculated.

FINDINGS

Biofilm formation was reproducible between assays. After exposure to detergent-disinfectants, the logarithmic reduction was between 6.32 and 6.71 log10 cfu/cm2 in the Tygon tubes. No bacteria were found in their supernatants. Results in the detergent-disinfectant group were not affected by the exposure temperature or the addition of enzymes. No decrease in the bacterial load was observed in the Tygon tubes after exposure to the enzymatic detergent. Bacteria were found in its supernatant.

CONCLUSION

These results show the importance of the choice of products used during the manual cleaning phase. They also show the potential benefit of combining detergent and disinfectant activity to decrease the bacterial load during the manual cleaning step of endoscope processing.

Pulling the plug on a pseudomonas outbreak: ancillary equipment as vectors of infection

OBJECTIVES

Outbreaks of infection related to flexible endoscopes are well described. However, flexible endoscopy also requires the use of ancillary equipment such as irrigation plugs. These are potential vectors of infection but are infrequently highlighted in the literature. This paper reports a cystoscopy-associated outbreak of Pseudomonas aeruginosa from contaminated irrigation plugs in a UK tertiary care centre.

METHODS

Laboratory, clinical and decontamination unit records were reviewed, and audits of the decontamination unit were performed. Flexible cystoscopes and irrigation plugs were assessed for contamination. Retrospective and prospective case finding was performed utilizing the microbiology laboratory information management system. Available P. aeruginosa isolates underwent variable nucleotide tandem repeat (VNTR) typing. Confirmed cases were defined as P. aeruginosa infection with an identical VNTR profile to an outbreak strain.

RESULTS

Three strains of P. aeruginosa were isolated from five irrigation plugs but none of the flexible cystoscopes. No acquired resistance mechanisms were detected. Fifteen confirmed infections occurred, including bacteraemia, septic arthritis and urinary tract infection. While failure of decontamination likely occurred because the plugs were not dismantled prior to reprocessing, the manufacturer's reprocessing instructions were also incompatible with standard UK practice. The Medicines and Healthcare Products Regulatory Agency was informed. A field safety notice was issued, and the manufacturer issued updated reprocessing instructions.

CONCLUSIONS

Ancillary equipment can represent an important vector for infection, and should be considered during outbreak investigations. Users should review the manufacturer's instructions for reprocessing ancillary equipment to ensure that they are compatible with available procedures.

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.

Efficacy of high-level disinfection of endoscopes contaminated with Streptococcus equi subspecies equi with 2 different disinfectants

BACKGROUND

Prevention of spread of Streptococcus equi subspecies equi (S. equi) after an outbreak is best accomplished by endoscopic lavage of the guttural pouch, with samples tested by culture and real time, quantitative polymerase chain reaction (qPCR). Disinfection of endoscopes must eliminate bacteria and DNA to avoid false diagnosis of carrier horses of S. equi.

HYPOTHESIS/OBJECTIVES

Compare failure rates of disinfection of endoscopes contaminated with S. equi using 2 disinfectants (accelerated hydrogen peroxide [AHP] or ortho-phthalaldehyde [OPA]). The null hypothesis was that there would be no difference between the AHP and OPA products (based on culture and qPCR results) after disinfection.

METHODS

Endoscopes contaminated with S. equi were disinfected using AHP, OPA or water (control). Samples were collected before and after disinfection and submitted for detection of S. equi by culture and qPCR. Using a multivariable logistic regression model-adjusted probability, with endoscope and day as controlled variables, the probability of an endoscope being qPCR-positive was determined.

RESULTS

After disinfection, all endoscopes were culture-negative (0%). However, the raw unadjusted qPCR data were positive for 33% AHP, 73% OPA, and 71% control samples. The model-adjusted probability of being qPCR-positive after AHP disinfection was lower (0.31; 95% confidence interval [CI], -0.03-0.64) compared to OPA (0.81; 95% CI, 0.55-1.06), and control (0.72; 95% CI, 0.41-1.04).

CONCLUSION AND CLINICAL IMPORTANCE

Disinfection using the AHP product resulted in significantly lower probability of endoscopes being qPCR-positive compared to the OPA product and control.

Unlocking quality in endoscopic mucosal resection

A review of the development of the key performance metrics of endoscopic mucosal resection (EMR), learning from the experience of the establishment of widespread colonoscopy quality measurements. Potential future performance markers for both colonoscopy and EMR are also evaluated to ensure continued high quality performance is maintained with a focus service framework and predictors of patient outcome.

Systematic Review and Cost-Consequence Analysis of Ambu aScope 5 Broncho Compared with Reusable Flexible Bronchoscopes: Insights from Two US University Hospitals and an Academic Institution

OBJECTIVE

The aim of this study was to perform a systematic review, meta-analysis and cost-consequence analysis of the single-use bronchoscope, Ambu aScope^TM 5 Broncho, in relation to reusable flexible bronchoscopes (RFB) available within three high procedure volume university hospitals and academic institutions in the USA.

METHODS

The primary outcome was incremental cost and the secondary outcome was incremental cross-infection risk of use for both the single-use flexible bronchoscope (SUFB) and RFBs. Cost estimates included capital, repair, and reprocessing costs derived from a prospective observational micro-costing approach within three large university hospitals and academic institutions. All costs were valued in 2022 US dollars (USD). A meta-analysis based on literature covering cross-contamination and infection from 2010 to 2020 investigated cross-infection risk following bronchoscopy procedures with RFBs. Capital costs were discounted at 3% over 5-8 years. All parameters were evaluated using both univariate deterministic and probabilistic sensitivity analyses.

RESULTS

In high-volume hospitals, RFBs were cost minimizing compared to SUFBs. Probabilistic sensitivity analysis showed that RFBs were cost saving in 88% of iterations. Univariate analyses illustrated sensitivity of the base-case result to the procedure volume. Data from sensitivity analyses suggest that the two interventions are cost neutral at a break-even point of 756 procedures per year or 46 procedures per bronchoscope per year.

CONCLUSION

Assuming equivalent clinical performance, single-use flexible bronchoscopes are not cost minimizing when including the costs associated with cross-infection in high-volume US university hospitals and academic institutions. Overall, the benefits of conversion from RFBs to SUFBs are dependent on the annual procedure volume of individual hospitals, expected cross-infection risk, and purchase price of the aScope 5 Broncho.

[A systematic analysis of nosocomial outbreaks of nosocomial infections after gastrointestinal endoscopy]

Esophagogastroduodenoscopy (EGD), endoscopic retrograde cholangiopancreatography (ERCP) and colonoscopy (CLN) come with a potential risk of pathogen transmission. Unfortunately, up to now data on the causes and the distribution of pathogens is rather sparse.We performed a systematic review of the medical literature using the Worldwide Outbreak Database, the PubMed, and Embase. We then checked so-retrieved articles for potential sources of the outbreak, the spectrum of pathogens, the attack rates, mortality and infection control measures.In total 73 outbreaks (EGD: 24, ERCP: 42; CLN: 7) got included. The corresponding attack rates were 3.5%, 7.1% and 12.8% and mortality rates were 6.3%, 12.7% and 10.0% respectively. EGD was highly associated with transmission of enterobacteria including a large proportion of multi-drug resistant strains. ERCP led primarily to transmission of non-fermenting gram-negative rods. The most frequent cause was human failure during reprocessing regardless of the type of endoscope.Staff working in the field of endoscopy should always be aware of the possibility of pathogen transmission in order to detect and terminate those events at the early most time point. Furthermore, proper ongoing education of staff involved in the reprocessing and maintenance of endoscopes is crucial. Single-use devices may be an alternative option and lower the risk of pathogen transmission, but on the downside may also increase costs and waste.

A Single-Blind Study Testing the Preparation Accuracy of Bedside Precleaning Solutions Used for Flexible Endoscopes

Endoscopy-related pathogen transmission may occur if microorganisms are spread from patient to patient by contaminated equipment. Effective and safe endoscope reprocessing includes bedside precleaning, mechanical cleaning, high-level disinfection, storage, and drying. The aim of this research study was to observe and report on the variation in practice regarding the use of detergent for bedside precleaning of flexible gastrointestinal endoscopes. Endoscopy nurses working in the endoscopy unit at the Princess Alexandra Hospital, Australia, prepared four samples of detergent solution as per normal routine. Twenty-nine nurses participated providing in total 116 samples. There was a significant variation in detergent concentration. The detergent concentration variated between 2.00 and 288.20 ml/L ( M = 34.55, SD = 39.21). Two samples revealed lower concentrations than required. More than 25% of the samples contained at least a 10 times higher concentration than required (>40 ml/L). Current practice of bedside precleaning of gastrointestinal endoscopes was not deemed safe or cost-effective as it did not guarantee an adequate concentration of detergent. More precise methods to establish the required concentration of the bedside precleaning solution were introduced to improve practice.

Cross-contamination rate of reusable flexible bronchoscopes: A systematic literature review and meta-analysis

Background

Bronchoscopy is generally a safe and efficient procedure. However, the risk of cross-contamination with reusable flexible bronchoscopes (RFB) has been detected in several outbreaks worldwide.

Aim

To estimate the average cross-contamination rate of patient-ready RFBs based on available published data.

Methods

We performed a systematic literature review in PubMed and Embase to investigate the cross-contamination rate of RFB. Included studies identified indicator organisms or colony forming units (CFU) levels, and total number of samples >10. The Contamination threshold was defined according to the European Society of Gastrointestinal Endoscopy and European Society of Gastrointestinal Endoscopy Nurse and Associates (ESGE-ESGENA) guidelines. To calculate the total contamination rate, a random effects model was applied. Heterogeneity was analysed via a Q-test and illustrated in a forest plot. Publication bias was analysed via the Egger’s regression test and illustrated in a funnel plot.

Results

Eight studies fulfilled our inclusion criteria. The random effects model included 2169 samples and 149 events (positive tests). The total RFB cross-contamination rate was 8.69% ± 1.86 (standard division [SD]) (95% confidence interval [CI]: 5.06–12.33%). The result showed significant heterogeneity of 90% and publication bias.

Discussion

Significant heterogeneity and publication bias is likely associated with varying methodology and aversion towards publishing negative findings, respectively. Based on the cross-contamination rate an infection control paradigm shift is needed to ensure patient safety. We recommend to follow the Spaulding classification and classify RFBs as critical items. Accordingly, infection control measures such as obligatory surveillance, and implementing single-use alternatives must be considered where feasible.

Investigation of the Internal Conditions of 213 Reprocessed Endoscopic Channels

BACKGROUND AND AIMS

Studies have indicated that endoscope reprocessing failure might be attributed to internal damage or residual liquid in endoscopes. However, large-sample survey data on the internal conditions of endoscopic channels after reprocessing are lacking. This study used a borescope to investigate the internal cleanliness and damage of 213 endoscopic biopsy channels after reprocessing at the endoscopy center of the First Affiliated Hospital of Nanchang University, provided in theoretical basis for the efficacy of endoscope reprocessing and maintenance.

METHODS

A borescope was used to observe and analyze the inside of the endoscopic biopsy channel of 213 reprocessed endoscopes (in accordance with the Chinese health industry standard "Regulation for cleaning and disinfection technique of flexible endoscope (WS 507-2016). Each endoscope was observed for at least 10 minutes, and the results were recorded and evaluated by 5 researchers independently.

RESULTS

In all, 2504 images and 109 videos were recorded, and abnormal findings were classified into 10 categories: scratches (91.5%, 195/213), scratches with adherent peel (46.0%, 98/213), discolored areas (49.3%, 105/213), transparent drops (28.2%, 60/213), milky drops (23.9%, 51/213), white particles (46.9%, 100/213), attached materials (37.6%, 80/213), wear on metal parts (41.3%, 88/213), rust (23.9%, 51/213), and black spots (35.7%, 76/213). Among scratches, those in Teflon from 0-10 cm at the apex of the biopsy channel outlet and in metal from 0-5 cm at the biopsy channel inlet accounted for 58.4% (114/195) and 96.4% (188/195), respectively.

CONCLUSIONS

Scratches were the most common form of damage in the endoscopic biopsy channels investigated and were related to the use of endoscopic accessories and cleaning brush materials. The incidence of other abnormalities gradually increased with the duration of use and began to increase significantly after 18 months. All abnormalities have a certain impact on the quality of endoscope reprocessing. We recommend that a borescope be used to check the inside of endoscopic biopsy channels regularly to determine the damage and cleaning conditions and that these channels be reprocessed, repaired, or replaced in a timely manner.

Single Use or Disposable Flexible Bronchoscopes: Bench Top and Preclinical Comparison of Currently Available Devices

BACKGROUND

Data regarding the risk of infection related to reusable bronchoscopes, the global drive toward disposable technology and the COVID-19 pandemic have led to an increase in the use and production of single use or disposable bronchoscopes. An in-depth comparison of all available devices has not been published.

METHODS

A benchtop comparison of the Ambu^®aScope^TM, Boston Scientific^® EXALT^TM Model B, the Surgical Company Broncoflex^© Vortex, Pentax^® Medical ONE Pulmo™, and Vathin^® H-Steriscope^TM (all 2.8 mm inner dimension other than the Pentax single-use flexible bronchoscope (3 mm)) was undertaken including measurement of maximal flexion and extension angles, thumb force required and suction with and without biopsy forceps. Thereafter, preclinical assessment was performed with data collected including experience, gender, hand size, and scope preference.

RESULTS

The Vathin single-use flexible bronchoscope had the biggest range of tip movement from flexion to extension with and without forceps. The Boston single-use flexible bronchoscope required the maximal thumb force but had the least reduction of tip movement with forceps. The Boston single-use flexible bronchoscope significantly outperformed all other scopes including the standard Pentax scope and was the only scope capable of suctioning pseudo-mucus around the forceps. Although there was no significant difference in preference in the overall group, females and those with smaller hand size preferred the Pentax and males the Broncoflex single-use flexible bronchoscope.

CONCLUSIONS

Currently available single-use flexible bronchoscopes differ in several factors other than scope sizes and monitor including suction, turning envelope, and handle size. Performance in the clinical setting will be key to their success.

Complications of diagnostic upper Gastrointestinal endoscopy: common and rare - recognition, assessment and management

A clear understanding of the potential complications or adverse events (AEs) of diagnostic endoscopy is an essential component of being an endoscopist. Creating a culture of safety and prevention of AEs should be part of routine endoscopy practice. Appropriate patient selection for procedures, informed consent, periprocedure risk assessments and a team approach, all contribute to reducing AEs. Early recognition, prompt management and transparent communication with patients are essential for the holistic and optimal management of AEs. In this review, we discuss the complications of diagnostic upper gastrointestinal endoscopy, including their recognition, treatment and prevention.

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.

Tolerance of biofilm of a carbapenem-resistant Klebsiella pneumoniae involved in a duodenoscopy-associated outbreak to the disinfectant used in reprocessing

Background

One possible transmission route for nosocomial pathogens is contaminated medical devices. Formation of biofilms can exacerbate the problem. We report on a carbapenemase-producing Klebsiella pneumoniae that had caused an outbreak linked to contaminated duodenoscopes. To determine whether increased tolerance to disinfectants may have contributed to the outbreak, we investigated the susceptibility of the outbreak strain to disinfectants commonly used for duodenoscope reprocessing. Disinfection efficacy was tested on planktonic bacteria and on biofilm.

Methods

Disinfectant efficacy testing was performed for planktonic bacteria according to EN standards 13727 and 14561 and for biofilm using the Bead Assay for Biofilms. Disinfection was defined as ≥ 5log₁₀ reduction in recoverable colony forming units (CFU).

Results

The outbreak strain was an OXA-48 carbapenemase-producing K. pneumoniae of sequence type 101. We found a slightly increased tolerance of the outbreak strain in planktonic form to peracetic acid (PAA), but not to other disinfectants tested. Since PAA was the disinfectant used for duodenoscope reprocessing, we investigated the effect of PAA on biofilm of the outbreak strain. Remarkably, disinfection of biofilm of the outbreak strain could not be achieved by the standard PAA concentration used for duodenoscope reprocessing at the time of outbreak. An increased tolerance to PAA was not observed in a K. pneumoniae type strain tested in parallel.

Conclusions

Biofilm of the K. pneumoniae outbreak strain was tolerant to standard disinfection during duodenoscope reprocessing. This study establishes for the first time a direct link between biofilm formation, increased tolerance to disinfectants, reprocessing failure of duodenoscopes and nosocomial transmission of carbapenem-resistant K. pneumoniae.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-022-01112-z.

The Cost of Flexible Bronchoscopes: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Until 2009, only reusable bronchoscopes were marketed, but the introduction and widespread adoption of single-use flexible bronchoscopes (SFBs) as an emerging technology has since accelerated. Several studies have described the costs of reusable flexible bronchoscopes (RFBs) and SFBs. This meta-analysis aimed to compile the current published evidence to analyse the cost of different scenarios using RFBs and SFBs.

METHODS

All published literature describing the cost of RFBs or SFBs was identified by searching PubMed, Embase and Google Scholar, limited to those between 1 January, 2009 and 6 November, 2020. Included studies should report the total cost of RFBs. Continuous data were extracted for relevant outcomes and analysed using RStudio^® 4.0.3 as the standardised mean difference and standard error of the mean in a mixed-effects model. Risk of bias was assessed based on the reporting quality.

RESULTS

In the systematic literature review, 342 studies were initially identified, and 11 were included in the final analysis. The mean RFB procedure cost was $266 (standard error of the mean: 34), including capital investments, repairs and reprocessing costs of $91, $92 and $83, respectively. The mean SFB procedure cost was $289 (standard error of the mean: 10). The incremental cost was $23 (standard error of the mean: 33) and was not significant (p = 0.46). Because of the economy of scale, RFB is more likely to be cost minimising compared with SFB when performing 306 or 39 procedures per site or RFB, respectively.

CONCLUSIONS

In this study, we found no significant difference in the cost of use between RFBs and SFBs and a high risk of bias.

Adoption of Improved Reprocessing Decreased Microbiological Non-Compliance for Bronchoscopes

BACKGROUND

In the past few decades, the inadequate reprocessing of bronchoscopes has been associated with several serious outbreaks caused by multidrug-resistant microorganisms. In this study we evaluated the improvement in the quality of reprocessing in a Bronchoscopy Unit (BU), after the introduction of a new procedure.

METHODS

In 2019, observational and clinical audits were conducted in the BU. After the introduction of an improved procedure in 2020, a microbiological surveillance plan was implemented in 2021.

RESULTS

In 2019, 13 of 22 bronchoscopes (59%) resulted as non-compliant, 18% as high concern organisms (HCO) and 36.4% as high microbial count (≥100 CFU/all channels) and HCO. The most frequent microorganisms were Staphylococcus aureus (38.5%) and NDM-producing Klebsiella pneumoniae (15.4%). The bronchoscopes were stored inside their transport cases, which in some cases were found to be contaminated by the same strains isolated on the bronchoscopes (Enterobacter gergoviae and Vibrio alginolyticus). In 2021, all 31 bronchoscopes were sampled at least three times and 13/99 (13.1%) resulted as non-compliant, mostly K. pneumoniae (4.04%). Contamination level increases weakly in bronchoscopes in use for more than 14 years (R = 0.32).

CONCLUSIONS

The adoption of an improved reprocessing procedure decreased the non-compliance of bronchoscopes, increasing the quality of the process and patient safety.

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.

Borescope Examination and Microbial Culture Results of Endoscopes in a Tertiary Care Hospital Led to Changes in Storage Protocols to Improve Patient Safety

BACKGROUND

Flexible endoscopes are highly versatile and useful medical instruments, and their proper reprocessing is critical to patient health and safety. The value of routine visual inspections and surveillance of endoscopes in a tertiary care hospital was assessed by performing borescope examinations and microbial sampling on respiratory, gastro-intestinal (GI), and urological endoscopes.

METHODS

A total of 42 endoscopes were cultured, and 36 endoscopes were examined with a borescope. The flush-brush-flush method was used to culture the endoscopes. Microbiologic sampling water was vortexed prior to being suctioned through a membrane filter device. The membrane was plated on a blood agar plate and incubated at 37°C for 48 hours. A 1.9-meter borescope with a 1.6mm diameter was used to perform borescope examinations in an antegrade and retrograde approach.

RESULTS

Positive microbial cultures were seen in 28% of bronchoscopes, 22% of GI endoscopes, and 30% of urological endoscopes. Only Gram-positive colonies were identified in endoscopes that had microbial growth. Borescope examinations revealed multiple abnormalities and damage including channel shredding, filamentous debris, water retention, discoloration, dents, and red particles.

CONCLUSIONS

Borescope examination and microbial sampling should be used routinely to assure endoscopic safety. Borescope examination enabled us to visualize structural damage, foreign material, and moisture within endoscopes. The structural damages and the particles found in endoscopes resulted in timely repair and discontinuation of this type of distal end protectors in our facility.

Risk factors for infections after endoscopic retrograde cholangiopancreatography (ERCP): a retrospective cohort analysis of US Medicare Fee-For-Service claims, 2015-2021

OBJECTIVE

Contaminated reprocessed duodenoscopes pose a serious threat to patients in the endoscopy unit. Despite manufacturer changes to reprocessing guidelines, 20% of reprocessed duodenoscopes meet criteria for quarantine-level contamination based on microbiological or ATP testing. We aimed to examine risk factors for postendoscopic retrograde cholangiopancreatography (ERCP) infection.

DESIGN

Retrospective cohort analysis.

SETTING

US Medicare Fee-For-Service claims (2015-2021) and all-payer data (2017).

PARTICIPANTS

In the Medicare data, 823 575 ERCP procedures were included. The all-payer five-state data, 16 609 procedures were included.

INTERVENTIONS

ERCP was identified by Current Procedural Terminology and International Classification of Disease (ICD) procedure codes. We identified inpatient infections using ICD diagnosis codes.

OUTCOME MEASURES

A logistic regression model predicted risk factors for infections occurring within 7-day and 30-day periods following ERCP. 7-day and 30-day all-cause hospitalisations and post-ERCP pancreatitis were also examined.

RESULTS

Post-ERCP infection occurred within 3.5% of 7-day and 7.7% of 30-day periods in Medicare. Disposable duodenoscopes were billed in 711 procedures, with 1.4% (n=10, 7-day) and 3.5% (n=25, 30-day) post-ERCP infections. Urgent ERCPs were the strongest risk factor for infections in the 7-day period (OR 3.3, 95% CI 3.2 to 3.4). Chronic conditions, sex (male), age (older) and race (non-white) were also risk factors. In the all-payer five-state data, fewer infections (2.4%, 7 days) were observed. No difference arose between Medicare and other payers for 7-day period infections (OR 1.0, 95% CI 0.7 to 1.3).

CONCLUSIONS

Urgent ERCPs, patient chronic conditions and patient demographics are post-ERCP infection risk factors. Patients with infection risk factors should be targeted for specialised infection control prevention measures, including disposable duodenoscopes.

Clinical and Endoscopic Consequences of Delay in Stent Exchange Procedures With ERCP During the Covid-19 Pandemic

INTRODUCTION

During the COVID-19 pandemic, elective endoscopic retrograde cholangiopancreatography (ERCP) procedures have been postponed as recommended by international guidelines. In this study, the results of biliary and pancreatic ERCP procedures that had to be postponed during the pandemic process were investigated.

MATERIALS AND METHODS

Forty-seven patients whose stent exchange procedures with ERCP were postponed between March 2020 and June 2020 due to the COVID-19 pandemic were included in the study. Patients were evaluated in 2 groups as delayed biliary procedures (n: 32) and delayed pancreatic procedures (n: 15). Clinical problems (biliary or pancreatic pain, itching, cholangitis, etc.) and technical problems encountered during the procedure (stent migration, abundant stone sludge in the bile ducts, etc.) were compared with 46 patients who could be treated without delay (39 interventions for the biliary system and seven interventions for the pancreas).

FINDINGS

Considering the procedures for the biliary system, there was no difference in age and sex between the groups. Although clinical problems in biliary procedures were more common in the group with delay than in those without delay, this difference was not significant (34% vs. 20%; P: 0.14). The technical problems encountered during the procedures in the group with delay were significantly higher than those without delay (21% vs. 2.5%; P: 0.019), with stent migration being the most common problem (n: 5). Age and sex did not differ in the patients who had pancreatic interventions with and without delay. The clinical problems that developed in the patients did not differ between the groups with and without delay (26% vs. 28%; P: 0.8). Although technical problems were encountered in 1 out of 15 patients in the group with delay, no technical problem was experienced in the group without delay (P: 0.68).

CONCLUSION

Postponing elective ERCP procedures for the biliary system not for the pancreatic system during the COVID-19 pandemic brings technical problems.

What is the best technic to dislodge Staphylococcus epidermidis biofilm on medical implants?

Background

Bacterial biofilm can occur on all medical implanted devices and lead to infection and/or dysfunction of the device.

In this study, artificial biofilm was formed on four different medical implants (silicone, piccline, peripheral venous catheter and endotracheal tube) of interest for our daily clinical and/or research practice. We investigated the best conventional technic to dislodge the biofilm on the implants and quantified the number of bacteria. Staphylococcus epidermidis previously isolated from a breast implant capsular contracture on a patient in the university hospital of Dijon was selected for its ability to produce biofilm on the implants. Different technics (sonication, Digest-EUR®, mechanized bead mill, combination of sonication plus Digest-EUR®) were tested and compared to detach the biofilm before quantifying viable bacteria by colony counting.

Results

For all treatments, the optical and scanning electron microscope images showed substantial less biofilm biomass remaining on the silicone implant compared to non-treated implant.

This study demonstrated that the US procedure was statistically superior to the other physical treatment: beads, Digest-EUR® alone and Digest-EUR® + US (p < 0.001) for the flexible materials (picc-line, PIV, and silicone). The number of bacteria released by the US is significantly higher with a difference of 1 log on each material. The result for a rigid endotracheal tube were different with superiority for the chemical treatment dithiothreitol: Digest-EUR®. Surprisingly the combination of the US plus Digest-EUR® treatment was consistently inferior for the four materials.

Conclusions

Depending on the materials used, the biofilm dislodging technique must be adapted. The US procedure was the best technic to dislodge S. epidermidis biofilm on silicone, piccline, peripheral venous catheter but not endotracheal tube. This suggested that scientists should compare themselves different methods before designing a protocol of biofilm study on a given material.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-022-02606-x.

Efficacy of a novel channel-cleaning ball brush for endoscope reprocessing: a randomized controlled trial

Background/Aims

Endoscopic channels are difficult to clean and can cause infection transmission. We examined the effectiveness of a newly developed channel-cleaning ball brush (BB), which is sucked into the endoscopic channel and scrapes and cleans the lumen as it passes through.

Methods

The upper and lower gastrointestinal endoscopes used for patient examinations were randomly selected as the conventional brush (CB) or BB group. After manual cleaning, the presence or absence of carbohydrates, proteins, adenosine triphosphate, and hemoglobin was assessed.

Results

Fifty-six and 58 endoscopes were cleaned with the CB and BB, respectively. Carbohydrate and protein were detected in one (1.8%) and two endoscopes (3.4%) in the CB and BB groups, respectively (p=1.000). Hemoglobin was observed in one (1.8%) and three endoscopes (5.2%) in the CB and BB groups, respectively (p=0.636). The adenosine triphosphate levels were 10.6±15.9 and 12.5±14.3 relative light units in the CB and BB groups, respectively (p=0.496). Twenty-seven (48.2%) and 19 (32.8%) endoscopes were positive for microbial cultures in the CB and BB groups, respectively (p=0.136).

Conclusions

The efficacy of BB was not significantly different from that of CB in the endoscopic channel-cleaning process.

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.