Exogenous endoscopy-related infections, pseudo-infections, and toxic reactions: clinical and economic burden

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.

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.

An outbreak of postoperative rapidly developing and multidrug-resistant Klebsiella pneumoniae urosepsis due to a contaminated ureteroscope

INTRODUCTION

Outbreaks caused by microorganisms contaminating the inside of rigid ureteroscopes are extremely rare. Some of these outbreaks, especially those caused by multidrug-resistant (MDR) infections, can cause serious problems, even death. Among these serious infections, we have no data about Klebsiellapneumoniae outbreaks caused by rigid ureteroscopes and their management and consequences.

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.

[Single-use products in endoscopy-from consumables to single-use scopes]

Clinically relevant infections triggered by the use of flexible endoscopes and respective consumables have become the focus of clinical and scientific interest in the literature. Endoscopy-associated infections can be assigned to one of two groups: (i) endogenous infections are triggered by the spread of the patient's own local flora and (ii) exogenous infections result from transmission of contaminated material or endoscopes. The number of reported infectious complications in flexible endoscopy is low but likely underestimated due to inadequate surveillance strategies and lack of clinical symptoms. To prevent exogenous infections, single-use endoscopes were brought to the market. Single-use bronchoscope have been part of routine clinical care for years, while single-use duodenoscopes have only recently been approved. The increased patient safety and economic costs were clearly evaluated for the single-use bronchoscopes, but this still needs to be studied for single-use duodenoscopes. The use of single-use endoscopes-at first glance-represents an additional financial burden on the healthcare system. However, in addition to the material costs of disposable endoscopes, the costs that are avoided by them (e.g., prolonged hospitalization, intensive care treatment, and follow-up interventions) must also be included in the overall calculation.

Outbreaks in Health Care Settings

Outbreaks and pseudo-outbreaks in health care settings are complex and should be evaluated systematically using epidemiologic and molecular tools. Outbreaks result from failures of infection prevention practices, inadequate staffing, and undertrained or overcommitted health care personnel. Contaminated hands, equipment, supplies, water, ventilation systems, and environment may also contribute. Neonatal intensive care, endoscopy, oncology, and transplant units are areas at particular risk. Procedures, such as bronchoscopy and endoscopy, are sources of infection when cleaning and disinfection processes are inadequate. New types of equipment can be introduced and lead to contamination or equipment and medications can be contaminated at the manufacturing source.

A bronchoscopy-associated pseudo-outbreak of Mycobacterium mucogenicum traced to use of contaminated ice used for bronchoalveolar lavage

Clonal Mycobacterium mucogenicum isolates (determined by molecular typing) were recovered from 19 bronchoscopic specimens from 15 patients. None of these patients had evidence of mycobacterial infection. Laboratory culture materials and bronchoscopes were negative for Mycobacteria. This pseudo-outbreak was caused by contaminated ice used to provide bronchoscopic lavage. Control was achieved by transitioning to sterile ice.

Scoping the scope: endoscopic evaluation of endoscope working channels with a new high-resolution inspection endoscope (with video)

BACKGROUND AND AIMS

Outbreaks of transmission of infection related to endoscopy despite reported adherence to reprocessing guidelines warrant scrutiny of all potential contributing factors. Recent reports from ambulatory surgery centers indicated widespread significant occult damage within endoscope working channels, raising concerns regarding the potential detrimental impact of this damage on the adequacy of endoscope reprocessing.

METHODS

We inspected working channels of all 68 endoscopes at our academic institution using a novel flexible inspection endoscope. Inspections were recorded and videos reviewed by 3 investigators to evaluate and rate channel damage and/or debris. Working channel rinsates were obtained from all endoscopes, and adenosine triphosphate (ATP) bioluminescence was measured.

RESULTS

Overall endoscope working channel damage was rated as minimal and/or mild and was consistent with expected wear and tear (median 1.59 on our 5-point scale). Our predominant findings included superficial scratches (98.5%) and scratches with adherent peel (76.5%). No channel perforations, stains, or burns were detected. The extent of damage was not predicted by endoscope age. Minor punctate debris was common, and a few small drops of fluid were noted in 42.6% of endoscopes after reprocessing and drying. The presence of residual fluid predicted higher ATP bioluminescence values. The presence of visualized working channel damage or debris was not associated with elevated ATP bioluminescence values.

CONCLUSION

The flexible inspection endoscope enables high-resolution imaging of endoscope working channels and offers endoscopy units an additional modality for endoscope surveillance, potentially complementing bacterial cultures and ATP values. Our study, conducted in a busy academic endoscopy unit, indicated predominately mild damage to endoscope working channels, which did not correlate with elevated ATP values.

New Developments in the Prevention of Gastrointestinal Scope-Related Infections

Gastrointestinal endoscopes are used for diagnostic and therapeutic purposes and are the most common medical device implicated in health care-associated outbreaks. Infections can be divided into endogenous or exogenous. Exogenous infections were associated with lapses in reprocessing. Recent outbreaks have occurred despite compliance with reprocessing guidelines and highlight the challenges with clearance of all organisms from the duodenoscopes and the potential role of biofilms in hindering adequate reprocessing. This review provides an overview of recent developments and the current understanding of the key contributing factors related to gastrointestinal endoscope-related infections and current approaches to identify and prevent these complications.

Microbiological monitoring of medical devices after cleaning, disinfection and sterilisation

The use of reusable semi-critical devices has been extended in current medical practice for both diagnostic and therapeutic purposes. However, reuse of these instruments carries the risk of cross-transmission of microorganisms from one patient to another. The process of cleaning and disinfecting these devices is complex, long, expensive and very error-prone. This paper analyses the epidemiological aspects of infections associated with the reuse of semi-critical devices and the role of the Microbiology laboratory in monitoring the cleaning and disinfecting process through microbiological controls. The recommendations of different scientific societies on the relevance of such controls are reviewed and specific recommendations are proposed for the taking and processing of the samples, interpretation of the results and measures to be taken depending on the results obtained.

Outbreak of Hospital Infection from Biofilm-embedded Pan Drug-resistant Pseudomonas aeroginosa, Due to a Contaminated Bronchoscope

Background

Colistin-resistant Pseudomonas aeruginosa (P. aeruginosa) has been defined as pandrug-resistant (PDR) strain. Outbreaks of PDR P. aeruginosa especially in pulmonary tract infections due to contaminated bronchoscopes have rarely been reported. The emergence of pandrug-resistant strains in both CF (Cystic Fibrosis) and non-CF clinical isolates over recent years remains of a great concern. Hospital wards contaminated with PDR P. aeruginosa infection, must be shot down until their eradication. Health Authorities must be informed immediately and infection control strategies must be implemented.

Aim

To report such an outbreak and modify the infection control strategy in an academic hospital in Ankara Turkey.

Methods

From October to December 2013, PDR-Pseudomonas aerogionsa were identified from bronchial cultures of 15 patients who had undergone bronchoscopy prior to the infection. Three batches of surveillance cultures were obtained from the environmental objects and healthcare workers related to the procedures. Pulsed-field gel electrophoresis (PFGE) was used for bacterial typing. Antimicrobial susceptibility was assessed by disc diffusion and E-test methods.

Findings

A total of 70 specimens were obtained during the first surveillance operation. One Colistin-resistant P. aeroginosa was isolated from a bronchoscope. Although the disinfection protocols for bronchoscope were revised and implemented, seven additional bronchial cases were identified thereafter. The pathogen was identified from two subsequent surveillance cultures and was not eliminated until Ethylene oxide sterilization was added to the disinfection protocol. PFGE revealed that all 15 isolates from the patients and the three isolates from the bronchoscope shared a common pattern with minor variance. XbaI restriction enzyme turned out better than SpeI in interpreting bacterial pulse types with BioNumerics 6.0. The most suitable cut off value for SpeI was above 80% Dice similarity while for XbaI above 95%Dice similarity with BioNumerics 6.0.

Conclusion

The outbreak of "Colistin" pan drug-resistant Pseudomonas aeroginosa was caused by a contaminated bronchoscope and was terminated by the implementation of a revised disinfection protocol for bronchoscope.

Adenosine triphosphate bioluminescence for bacteriologic surveillance and reprocessing strategies for minimizing risk of infection transmission by duodenoscopes

BACKGROUND AND AIMS

Recent outbreaks of duodenoscope-transmitted infections underscore the importance of adequate endoscope reprocessing. Adenosine triphosphate (ATP) bioluminescence testing allows rapid evaluation of endoscopes for bacteriologic/biologic residue. In this prospective study we evaluate the utility of ATP in bacteriologic surveillance and the effects of endoscopy staff education and dual cycles of cleaning and high-level disinfection (HLD) on endoscope reprocessing.

METHODS

ATP bioluminescence was measured after precleaning, manual cleaning, and HLD on rinsates from suction-biopsy channels of all endoscopes and elevator channels of duodenoscopes/linear echoendoscopes after use. ATP bioluminescence was remeasured in duodenoscopes (1) after re-education and competency testing of endoscopy staff and subsequently (2) after 2 cycles of precleaning and manual cleaning and single cycle of HLD or (3) after 2 cycles of precleaning, manual cleaning, and HLD.

RESULTS

The ideal ATP bioluminescence benchmark of <200 relative light units (RLUs) after manual cleaning was achieved from suction-biopsy channel rinsates of all endoscopes, but 9 of 10 duodenoscope elevator channel rinsates failed to meet this benchmark. Re-education reduced RLUs in duodenoscope elevator channel rinsates after precleaning (23,218.0 vs 1340.5 RLUs, P < .01) and HLD (177.0 vs 12.0 RLUs, P < .01). After 2 cycles of manual cleaning/HLD, duodenoscope elevator channel RLUs achieved levels similar to sterile water, with corresponding negative cultures.

CONCLUSIONS

ATP testing offers a rapid, inexpensive alternative for detection of endoscope microbial residue. Re-education of endoscopy staff and 2 cycles of cleaning and HLD decreased elevator channel RLUs to levels similar to sterile water and may therefore minimize the risk of transmission of infections by duodenoscopes.

A novel self-propelled disposable colonoscope is effective for colonoscopy in humans (with video)

BACKGROUND AND AIMS

The self-propelled disposable colonoscope (SPDC) with a 360° view is designed to enhance visualization, minimize risks of perforation and infection transmission, and shorten operator training time associated with conventional colonoscopy (CC). We evaluated SPDC efficacy for cecal intubation and safety.

METHODS

Prospective patients presenting for colorectal cancer screening underwent SPDC immediately followed by CC. Initial patients necessary for SPDC operators to achieve proficiency comprised the training cohort. Subsequent enrolled patients comprised the study cohort. SPDC colonoscopy was performed up to the cecum, where anatomic landmarks were photographed and mucosal suction marks were placed. During SPDC withdrawal, polyps were recorded and similarly marked. On the second pass (by using CC), any potential mucosal damage and suction marks from the SPDC as well as polyps were recorded. Main endpoints included SPDC cecal intubation rates, confirmed by anatomic landmarks and residual marks seen on subsequent CC, and frequency and severity of adverse events and mucosal damage with SPDC. The secondary endpoint was subjective procedure proficiency, evaluated by the operator based on the training cohort. The tertiary endpoint was documenting pathologies visualized with SPDC.

RESULTS

Fifty-six of 58 enrolled subjects completed the study. Proficiency with SPDC was attained after 8 to 10 procedures. Cecal intubation was successful in 98.2% (55/56 subjects; 95% confidence interval [CI], 90.4%-99.9%), including 100% (95% CI, 90.7%-100%) of the study cohort and 94.4% (95% CI, 72.7%-99.9%) of the training cohort. No mucosal damage or adverse events were reported. SPDC detected 87.5% of polyps seen in tandem CC, including all polyps larger than 5 mm.

CONCLUSIONS

SPDC was highly successful, simple to use, and safe in achieving complete colonoscopy (cecal intubation). (

CLINICAL TRIAL REGISTRATION NUMBER

0692-12-TLV.).

Transmission of infection by flexible gastrointestinal endoscopy and bronchoscopy

Flexible endoscopy is a widely used diagnostic and therapeutic procedure. Contaminated endoscopes are the medical devices frequently associated with outbreaks of health care-associated infections. Accurate reprocessing of flexible endoscopes involves cleaning and high-level disinfection followed by rinsing and drying before storage. Most contemporary flexible endoscopes cannot be heat sterilized and are designed with multiple channels, which are difficult to clean and disinfect. The ability of bacteria to form biofilms on the inner channel surfaces can contribute to failure of the decontamination process. Implementation of microbiological surveillance of endoscope reprocessing is appropriate to detect early colonization and biofilm formation in the endoscope and to prevent contamination and infection in patients after endoscopic procedures. This review presents an overview of the infections and cross-contaminations related to flexible gastrointestinal endoscopy and bronchoscopy and illustrates the impact of biofilm on endoscope reprocessing and postendoscopic infection.

Outbreak of ertapenem-resistant Enterobacter cloacae urinary tract infections due to a contaminated ureteroscope

BACKGROUND

Outbreaks of urinary tract infections (UTIs) due to contaminated ureteroscopes have been rarely reported.

AIM

To report such an outbreak at a regional teaching hospital in southern Taiwan.

METHODS

From October to December 2010, ertapenem-resistant Enterobacter cloacae were identified from urine cultures of 15 patients who had undergone ureteroscopy prior to the infection. Three batches of surveillance cultures were obtained from the environmental objects and healthcare workers related to the procedures. Pulsed-field gel electrophoresis (PFGE) was used for bacterial typing. Antimicrobial susceptibility was assessed by disc diffusion and E-test methods. Polymerase chain reaction and sequencing were used to analyse β-lactamase genes.

FINDINGS

A total of 70 specimens were obtained during the first surveillance operation. One ertapenem-resistant E. cloacae was isolated from a ureteroscope. Although the disinfection protocols for ureteroscopes were revised and implemented, seven additional UTI cases were identified thereafter. The pathogen was identified from two subsequent surveillance cultures and was not eliminated until ethylene oxide sterilization was added to the disinfection protocol. PFGE revealed that all 15 isolates from the patients and the three isolates from the ureteroscope shared a common pattern with minor variance. Most isolates were resistant to gentamicin, levofloxacin, ceftriaxone, ceftazidime, and ertapenem. All isolates were susceptible to amikacin, imipenem, and meropenem. SHV-12 and IMP-8 genes were simultaneously identified in 16 of the 18 isolates.

CONCLUSION

The outbreak of ertapenem-resistant E. cloacae was caused by a contaminated ureteroscope and was terminated by the implementation of a revised disinfection protocol for ureteroscopes.

The new requirements of endoscopy

The following on new requirements of endoscopy contains commentaries on the risk of infection in endoscopy, the need to eliminate contamination, and the use of a disposable system in transnasal endoscopy.

Microbiologic assessment of disposable sterile endoscopic sheaths to replace high-level disinfection in reprocessing: a prospective clinical trial with nasopharygoscopes

BACKGROUND

Conventional reprocessing of endoscopes with high-level disinfection is labor intensive, expensive, delays the turnover of instruments, and involves potential exposure of personnel to toxic chemicals. We report a prospective clinical trial with rigorous microbiologic assessment of a novel disposable, sterile, polyurethane sheath, which can be easily and snugly applied over a nasopharyngoscope before performing the endoscopic procedure, with enzymatic cleansing and disinfection of the instrument with 70% ethanol following the procedure to determine whether the use of the novel sheath can provide reliable protection against bacterial contamination and obviate the need for routine high-level disinfection in reprocessing.

METHODS

Baseline cultures were obtained at 3 time periods from the control heads and insertion shafts of nasopharyngoscopes used in 100 clinical examinations: before application of the protective sheath and execution of the procedure; immediately after the procedure and removal of the sheath; and after enzymatic cleaning, disinfection with 70% ethanol, and drying. All 100 used sheaths and 20 unused sheaths were subjected to high-pressure leak testing to assess barrier integrity.

RESULTS

Bacteria were detected on 16 control heads and 6 shafts prior to the procedure; from 13 heads and 1 shaft immediately following the nasopharyngoscopic procedure and sterile sheath removal; and none of the instruments following cleaning, ethanol disinfection, and drying. No sheath showed loss of barrier integrity on leak testing.

CONCLUSION

Use of a high-quality, snugly fitting, sterile, disposable polyurethane sheath on a nasopharyngoscope during a clinical examination, combined with enzymatic detergent cleaning and disinfection with 70% ethanol, can provide a reliably decontaminated, patient-ready instrument, eliminating the need for high-level disinfection of endoscopes.

Patient to patient transmission of hepatitis B virus: a systematic review of reports on outbreaks between 1992 and 2007

BACKGROUND

Hepatitis B outbreaks in healthcare settings are still a serious public health concern in high-income countries. To elucidate the most frequent infection pathways and clinical settings involved, we performed a systematic review of hepatitis B virus outbreaks published between 1992 and 2007 within the EU and USA.

METHODS

The research was performed using two different databases: the PubMed Database and the Outbreak Database, the worldwide database for nosocomial outbreaks. Selection of papers was carried out using the Quorom algorithm, and to avoid selection biases, the inclusion criteria were established before the articles were identified.

RESULTS

Overall, 30 papers were analyzed, reporting on 33 hepatitis B virus outbreaks that involved 471 patients, with 16 fatal cases. Dialysis units accounted for 30.3% of outbreaks followed by medical wards (21.2%), nursing homes (21.2%), surgery wards (15.2), and outpatient clinics (12.1%). The transmission pathways were: multi-vial drugs (30.3%), non-disposable multi-patient capillary blood sampling devices (27.2%), transvenous endomyocardial biopsy procedures (9.1%), and multiple deficiencies in applying standard precautions (9.1%).

CONCLUSION

The analysis of transmission pathways showed that some breaches in infection control measures, such as administration of drugs using multi-vial compounds and capillary blood sampling, are the most frequent routes for patient-to-patient transmission of hepatitis B virus. Moreover some outbreak reports underlined that heart-transplant recipients are at risk of contracting hepatitis B virus infection during the transvenous endomyocardial biopsy procedure through indirect contact with infected blood as a result of environmental contamination. To prevent transmission, healthcare workers must adhere to standard precautions and follow fundamental infection control principles, such as the use of sterile, single-use, disposable needles and avoiding the use of multi-vial compounds in all healthcare settings including outpatient settings.

Endoscopy-related infection: relic of the past?

PURPOSE OF REVIEW

Recent outbreaks of nosocomial infection and pseudoinfection have been linked to contaminated endoscopes. This review summarizes the recent literature, analyzes the latest published information related to the epidemiology, examines potential causes for the outbreaks, and discusses current alternatives for preventing infection.

RECENT FINDINGS

A systematic follow-up of patients revealed that the risk of infection attributed to inadequate endoscope reprocessing was very low. Nevertheless, inadequate reprocessing practices are still considered the main culprit underlying contamination from endoscopy procedures. Moreover, standards of care are difficult to maintain given the numerous inconsistencies that exist among reprocessing guidelines and manufacturer's recommended practices. Exposure to contaminated equipment could be prevented through better reprocessing practices and adherence to decontamination guidelines. Recent literature reinforces the need for endoscopy drying after each reprocessing cycle, endoscope reprocessing after short periods of disuse, surveillance, and for a coordinated approach to handle postcontamination responses. Additional analyses such as health technology assessment and cost analysis are needed to identify control alternatives that are most effective.

SUMMARY

Although the risk of endoscopy-related infection is very low, continued efforts are needed to ensure that quality is maintained during endoscope reprocessing to reduce the incidence of endoscopy-related infections.