Bronchoscopy-related outbreaks and pseudo-outbreaks: A systematic review.

OBJECTIVE: To identify and report the pathogens and sources of contamination associated with bronchoscopy-related outbreaks and pseudo-outbreaks. DESIGN: Systematic review. SETTING: Inpatient and outpatient outbreaks and pseudo-outbreaks after bronchoscopy. METHODS: PubMed/Medline databases were searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, using the search terms "bronchoscopy," "outbreak," and "pseudo-outbreak" from inception until December 31, 2022. From eligible publications, data were extracted regarding the type of event, pathogen involved, and source of contamination. Pearson correlation was used to identify correlations between variables. RESULTS: In total, 74 studies describing 23 outbreaks and 52 pseudo-outbreaks were included in this review. The major pathogens identified in these studies were Pseudomonas aeruginosa, Mycobacterium tuberculosis, nontuberculous mycobacteria (NTM), Klebsiella pneumoniae, Serratia marcescens, Stenotrophomonas maltophilia, Legionella pneumophila, and fungi. The primary sources of contamination were the use of contaminated water or contaminated topical anesthetics, dysfunction and contamination of bronchoscopes or automatic endoscope reprocessors, and inadequate disinfection of the bronchoscopes following procedures. Correlations were identified between primary bronchoscope defects and the identification of P. aeruginosa (r = 0.351; P = .002) and K. pneumoniae (r = 0.346; P = .002), and between the presence of a contaminated water source and NTM (r = 0.331; P = .004) or L. pneumophila (r = 0.280; P = .015). CONCLUSIONS: Continued vigilance in bronchoscopy disinfection practices remains essential because outbreaks and pseudo-outbreaks continue to pose a significant risk to patient care, emphasizing the importance of stringent disinfection and quality control measures.

Both microbiological surveillance and audit of procedures improve reprocessing of flexible bronchoscopes and patient safety.

BACKGROUND: Microbiological surveillance of bronchoscopes and automatic endoscope reprocessors (AERs)/washer disinfectors as a quality control measure is controversial. Experts also are divided on the infection risks associated with bronchoscopic procedures. OBJECTIVE: We evaluated the impact of routine microbiological surveillance and audits of cleaning/disinfection practices on contamination rates of reprocessed bronchoscopes. DESIGN: Audits were conducted of reprocessing procedures and microbiological surveillance on all flexible bronchoscopes used from January 2007 to June 2020 at a teaching hospital in France. Contamination rates per year were calculated and analyzed using a Poisson regression model. The risk factors for microbiological contamination were analyzed using a multivariable logistical regression model. RESULTS: In total, 478 microbiological tests were conducted on 91 different bronchoscopes and 57 on AERs. The rate of bronchoscope contamination significantly decreased between 2007 and 2020, varying from 30.2 to 0% (P < .0001). Multivariate analysis confirmed that retesting after a previous contaminated test was significantly associated with higher risk of bronchoscope contamination (OR, 2.58; P = .015). This finding was explained by the persistence of microorganisms in bronchoscopes despite repeated disinfections. However, the risk of persistent contamination was not associated with the age of the bronchoscope. CONCLUSIONS: Our results confirm that bronchoscopes can remain contaminated despite repeated reprocessing. Routine microbial testing of bronchoscopes for quality assurance and audit of decontamination and disinfection procedures can improve the reprocessing of bronchoscopes and minimize the rate of persistent contamination.

Bronchoscopy during the COVID-19 pandemic: effect on current practices and strategies to reduce procedure-associated transmission.

Introduction: Bronchoscopy and related procedures have unambiguously been affected during the Corona Virus Disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS COV-2). Ordinary bronchoscopy practices and lung cancer services might have changed over this pandemic and for the years to come.Areas covered: This manuscript summarizes the utility of bronchoscopy in COVID-19 patients, and the impact of the pandemic in lung cancer diagnostic services, in view of possible viral spread during these We conducted a literature review of articles published in PubMed/Medline from inception to November 5th, 2020 using relevant terms.Expert opinion: Without doubt this pandemic has changed the way bronchoscopy and related procedures are being performed. Mandatory universal personal protective equipment, pre-bronchoscopy PCR tests, dedicated protective barriers and disposable bronchoscopes might be the safest and simpler way to perform even the most complicated procedures.

A pseudo-outbreak of Rhinocladiella similis in a bronchoscopy unit of a tertiary care teaching hospital in London, United Kingdom.

Outbreaks of fungal infections due to emerging and rare species are increasingly reported in healthcare settings. We investigated a pseudo-outbreak of Rhinocladiella similis in a bronchoscopy unit of a tertiary care teaching hospital in London, UK. We aimed to determine route of healthcare-associated transmission and prevent additional infections. From July 2018 through February 2019, we detected a pseudo-outbreak of R. similis isolated from bronchoalveolar lavage (BAL) fluid samples collected from nine patients who had undergone bronchoscopy in a multispecialty teaching hospital, during a period of 8 months. Isolates were identified by MALDI-TOF mass spectrometry. Antifungal susceptibility testing was performed by EUCAST broth microdilution. To determine genetic relatedness among R. similis isolates, we undertook amplified fragment length polymorphism analysis. To determine the potential source of contamination, an epidemiological investigation was carried out. We reviewed patient records retrospectively and audited steps taken during bronchoscopy as well as the subsequent cleaning and decontamination procedures. Fungal cultures were performed on samples collected from bronchoscopes and automated endoscope washer-disinfector systems. No patient was found to have an infection due to R. similis either before or after bronchoscopy. One bronchoscope was identified to be used among all affected patients with positive fungal cultures. Physical damage was found in the index bronchoscope; however, no fungus was recovered after sampling of the affected scope or the rinse water of automated endoscope washer-disinfectors. Use of the scope was halted, and, during the following 12-month period, Rhinocladiella species were not isolated from any BAL specimen. All pseudo-outbreak isolates were identified as R. similis with high genetic relatedness (>90% similarity) on ALFP analysis. The study emphasises the emergence of a rare and uncommon black yeast R. similis, with reduced susceptibility to echinocandins, in a bronchoscope-related pseudo-outbreak with a potential water-related reservoir. Our findings highlight the importance of prolonged fungal culture and species-level identification of melanised yeasts isolated from bronchoscopy samples. Possibility of healthcare-associated transmission should be considered when R. similis is involved in clinical microbiology samples.

Bronchoscope-Related "Superbug" Infections.

Several recent cases associating cleaned and high-level disinfected duodenoscopes with outbreaks of carbapenem-resistant Enterobacteriaceae (CRE) and related multidrug-resistant organisms (MDROs) may cause bronchoscopists, pulmonologists, and other stakeholders to inquire about the effectiveness of today's practices for reprocessing flexible bronchoscopes. The primary objectives of this study were to address this question and investigate the risk of bronchoscopes transmitting infections of CRE and related MDROs. The published literature and the US Food and Drug Administration's medical device database of adverse events were searched beginning in 2012, when endoscopy first emerged as a recognized risk factor for transmission of CRE. The Internet was also searched during this same time frame to identify other relevant cases. Several cases associating reprocessed bronchoscopes with infections of CRE or a related MDRO were identified. This study's findings suggest that bronchoscopes may pose an underrecognized potential for transmission of CRE and related MDROs, warranting greater public awareness, enhanced preventive measures, and updated reprocessing guidance. This study's data also suggest that the cleaning and high-level disinfection of bronchoscopes performed in accordance with published guidelines and manufacturer instructions may not always be sufficiently effective to eliminate this risk. Several factors were identified that can adversely affect a bronchoscope's reprocessing and pose a risk of transmission of these multidrug-resistant bacteria, including use of a damaged or inadequately serviced bronchoscope, and formation of an inaccessible biofilm. Recommendations are provided to improve the safety of flexible bronchoscopes, including supplementing their reprocessing with an enhanced measure such as sterilization when warranted, and strict adherence to a periodic servicing and maintenance schedule consistent with the bronchoscope manufacturer's instructions.

Bronchoscope-related Pseudomonas aeruginosa pseudo-outbreak attributed to contaminated rinse water.

BACKGROUND: Increased percentage of Pseudomonas aeruginosa from bronchoalveolar lavage fluid of patients in June 2016 was observed. P aeruginosa were also obtained from flexible bronchoscope and rinse water in the microbiological surveillance in June 2016. METHODS: Reprocessing procedure of bronchoscope was assessed, and environmental samples were collected. P aeruginosa isolates recovered from bronchoalveolar lavage fluid of patients between May and September 2016 and environment were characterized using multilocus sequence typing and pulsed-field gel electrophoresis. RESULTS: A novel multilocus sequence type (ST) of P aeruginosa was defined as ST 2387. ST671 and ST 2387 were both cultured from bronchoscopes and connecting tube in manual reprocessing cleaning equipment. One strain from a patient was indistinguishable from the clones obtained from the bronchoscope and connecting tube revealed by pulsed-field gel electrophoresis. Two strains from 2 patients from the burn intensive care unit were identical, and highly related to 2 other strains from the burn intensive care unit. The persistence of P aeruginosa in bronchoscopes, connecting tubes, and final rinse water was terminated by replacement of the connecting tube. CONCLUSIONS: We report a pseudo-outbreak of P aeruginosa associated with bronchoscope, for which connecting tube was the hidden reservoir for contaminating bronchoscopes. This highlights that effective measures are needed to control the bacterial load in final rinsing water to protect reusable equipment from contamination in reprocessing and cleaning.

Mycobacterium avium pseudo-outbreak associated with an outpatient bronchoscopy clinic: Lessons for reprocessing.

We identified a pseudo-outbreak of Mycobacterium avium in an outpatient bronchoscopy clinic following an increase in clinic procedure volume. We terminated the pseudo-outbreak by increasing the frequency of automated endoscope reprocessors (AER) filter changes from quarterly to monthly. Filter changing schedules should depend on use rather than fixed time intervals.

Microbiological surveillance of flexible bronchoscopes after a high-level disinfection with peracetic acid: preliminary results from an Italian teaching hospital.

BACKGROUND: Flexible bronchoscopes are heat labile, complex and difficult to clean, and some nosocomial outbreaks related to bronchoscopy have been reported in literature. The aim of our study was to determine, through a systematic monitoring, whether bronchoscopes' cleaning and disinfection procedures have been correctly adopted by health operators. METHODS: We conducted a 19 months-long prospective study in the Unit of Pulmonology at Careggi Teaching Hospital (Florence, Italy), analyzing endoscopes that were reprocessed through a high-level disinfection procedure. Samples collection was performed weekly by two trained operators. Results were organized in a database and then exported for descriptive and inferential statistical analysis. RESULTS: From February 2016 to September 2017 we collected 218 samples from bronchoscopes' valves (N=109) and from their inner channels (N=109). Staphylococci were found in 34 samples (15.69% of all samples). Pseudomonas was found in 11 samples (5.04% of all samples). Pseudomonas aeruginosa wasn't found in any sample. CONCLUSIONS: Our results came out to be better than similar studies in literature and demonstrated that a correct endoscopes' hygiene should be part of a more complex strategy of surveillance and control of healthcare-associated infections. However, a continuous monitoring of endoscopes could provide a wider view about this problem, and more reliable results.

Hospital bronchoscopy-related pseudo-outbreak caused by a circulating Mycobacterium abscessus subsp. massiliense.

Adolfo Lutz Institute in Sao Paolo State performs mycobacterial identification for many healthcare units, and in 2008 identified a possible outbreak involving patients submitted to bronchoscopy at the same hospital. This study aimed to analyse the clonality of isolates. Mycobacterium abscessus subsp. massiliense isolated from 28 patients, water from one bronchoscope and water from four automated endoscope reprocessing machines presented high similarity by pulsed-field gel electrophoresis. This strain was not found in the water supply, and it was hypothesized that an infected patient contaminated the bronchoscope, with further false-positive cultures from subsequent patients.

Effectiveness of Reprocessing for Flexible Bronchoscopes and Endobronchial Ultrasound Bronchoscopes.

BACKGROUND: Infections have been linked to inadequately reprocessed flexible bronchoscopes, and recent investigations determined that pathogen transmission occurred even when bronchoscope cleaning and disinfection practices aligned with current guidelines. This multisite, prospective study evaluated the effectiveness of real-world bronchoscope reprocessing methods, using a systematic approach. METHODS: This study involved direct observation of reprocessing methods for flexible bronchoscopes, multifaceted evaluations performed after manual cleaning and after high-level disinfection, and assessments of storage conditions. Visual inspections of ports and channels were performed using lighted magnification and borescopes. Contamination was detected using microbial cultures and tests for protein, hemoglobin, and adenosine triphosphate (ATP). Researchers assessed reprocessing practices, and storage cabinet cleanliness was evaluated by visual inspection and ATP tests. RESULTS: Researchers examined 24 clinically used bronchoscopes. After manual cleaning, 100% of bronchoscopes had residual contamination. Microbial growth was found in 14 fully reprocessed bronchoscopes (58%), including mold, Stenotrophomonas maltophilia, and Escherichia coli/Shigella species. Visible irregularities were observed in 100% of bronchoscopes, including retained fluid; brown, red, or oily residue; scratches; damaged insertion tubes and distal ends; and filamentous debris in channels. Reprocessing practices were substandard at two of three sites. CONCLUSIONS: Damaged and contaminated bronchoscopes were in use at all sites. Inadequate reprocessing practices may have contributed to bioburden found on bronchoscopes. However, even when guidelines were followed, high-level disinfection was not effective. A shift toward the use of sterilized bronchoscopes is recommended. In the meantime, quality management programs and updated reprocessing guidelines are needed.

Contamination of single-use bronchoscopes in critically ill patients.

Disposable bronchoscopes such as the Ambu aScopeTM 3 are marketed as 'single use' The risks of contamination from prolonged device storage before possible re-use are unknown. Following clinical bronchoscopy in patients whose lungs were mechanically ventilated, 20 aScopeTM 3's bronchoscopes received a standard 'social clean' and were then stored. Subsequent paired saline flush and swab samples were taken at time zero, and at 24 h and 48 h. Positive microbiological cultures were obtained from at least one time point from 16 of the 20 bronchoscopes. Pathogens considered at high risk of causing pneumonia were isolated from seven bronchoscopes, with significant quantities from six of them. Our study demonstrates that aScopeTM 3's should not be re-used on the same patient, as clinically significant growth of micro-organisms occurs frequently, despite adequate social cleaning. Culture of bronchoscopes themselves may be a potentially useful diagnostic tool in the context of pulmonary infection. Our data make it clear that these devices are single use and not single patient use.

A Pseudo-Outbreak of Pseudomonas putida and Stenotrophomonas maltophilia in a Bronchoscopy Unit.

BACKGROUND: Endoscopes represent the medical devices most commonly linked to health care-associated outbreaks and pseudo-outbreaks. Most of the recent outbreaks and pseudo-outbreaks have resulted from contaminated automated endoscope reprocessors (AER) or the use of damaged or malfunctioning bronchoscopes or contaminated equipment. OBJECTIVES: We investigated a pseudo-outbreak of Pseudomonas putida and Stenotrophomonas maltophilia recovered from bronchial washing (BW) specimens obtained during bronchoscopy in a bronchoscopy unit. METHODS: Samples were obtained from environmental surfaces in the endoscopy suite, bronchoscopes, and bronchoscopic dispensable material, and specimens of cleaning solutions, cleaning brushes, the AER, and the ultrasound system were sent for bacterial culture. Medical records were reviewed to identify possible infections after a bronchoscopy. RESULTS: P. putida and S. maltophilia were isolated from BW samples of 39 patients. The bronchoscopy models Olympus BF-1T160 and BF-160 were contaminated. Both bronchoscopes and other contaminated material (cleaning brushes, diluted cleaning solutions, and the sink) were isolated, but new cases continued to appear. The AER was recently installed, and new connections were used for the water lines and new tubes were connected to the AER. Initially, specimens were obtained from the external circuits and the internal walls of the AER. Finally, cultures were made from the filters on the water lines, and growth of P. putida and S. maltophilia was found. The investigation revealed that the BW specimens were contaminated because sterile saline was injected by means of the biopsy port of the bronchoscope and was recovered through the same channel by means of the proximal suction port. No patients developed clinical signs or symptoms of infection, but the positive cultures did lead to treatment of 21 patients. CONCLUSIONS: We described a pseudo-outbreak related to a contaminated bronchoscope because of inadequate installation of the AER for used new water lines and because the new tubes were connected to the AER. The antibacterial filters of the AER used tap water, and this may have contained low levels of microorganisms. No serious clinical complications derived from this pseudo-outbreak.

Pseudooutbreak of rapidly growing mycobacteria due to Mycobacterium abscessus subsp bolletii in a digestive and respiratory endoscopy unit caused by the same clone as that of a countrywide outbreak.

BACKGROUND: The nontuberculous mycobacteria (NTM) are widely spread. In Brazil, 2,520 cases of rapidly growing mycobacteria (RGM) infections after medical procedures were reported, with 5.4% of cases related to nonsurgical invasive procedures and with an occurrence of 1 clone (BRA100) of Mycobacterium abscessus subsp bolletii. OBJECTIVE: To describe a pseudooutbreak of M abscessus subsp bolletii in an endoscopy and bronchoscopy unit. METHODS: The alert for a pseudooutbreak was given when 3 patients, in the same week, had a positive bronchoalveolar lavage culture for M abscessus subsp bolletii. The patients had no symptoms/signs of mycobacterial infection; thus, contamination of bronchoscopes was suspected. Samples for culturing were collected from bronchoscopes, digestive endoscopes, automated disinfection machines, and the water supply. Clinical samples were identified by polymerase chain reaction restriction-enzyme analysis (PRA) of the hsp65 gene and their pulsed-field gel electrophoresis pattern was compared with environmental samples. RESULTS: The investigation demonstrated a contamination of bronchoscopes, digestive endoscopes, and disinfection machines. Molecular typing demonstrated that all strains belonged to the same clone (MAB01), identical to clone BRA100. DISCUSSION: Cross-transmission due to poor disinfection as well as resistance to glutaraldehyde may play roles in the spread of MAB01 M abscessus subsp bolletii, which may have a unique resistance to the environment and adaption to human hosts. However the water supply may have played a role. Attention is needed to ensure the quality of water used to rinse disinfected equipment.

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

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

Pseudo-outbreak of Phaeoacremonium parasiticum from a hospital ice dispenser.

In 31 patients, Phaeoacremonium parasiticum was recovered from bronchoscopy specimens (biopsies and aspirates). The pseudo-outbreak was caused by contaminated ice used to control hemorrhage during bronchoscopy and was associated with deficiencies in equipment cleaning. The bronchoscopy technique was modified, the ice dispenser was disinfected, bronchoscope reprocessing was improved, and there were no recurrences.

Correlation between outbreaks of multidrug-resistant Pseudomonas aeruginosa infection and use of bronchoscopes suggested by epidemiological analysis.

An outbreak of Multi-Drug Resistance Pseudomonas aeruginosa (MDRP) infections occurred in intensive care unit (ICU) and emergency room (ER) between June and August 2007. Five patients who isolated MDRP in the outbreak of 2007 were all used bronchoscopes, thus, we suspected contamination of the bronchoscopes as the cause of outbreak. Although we did not detect MDRP from any bronchoscopes, the outbreak finally ended after all the bronchoscopes had been disinfected appropriately with the reexamination of washing process in 2008 and 2009. We retrospectively reviewed eleven patients who isolated MDRP in 2006 and 2007, and the fact was revealed that bronchoscopes were used in most patients in ICU and ER. Bronchoscopes were significantly used during 2006-2007 period, compared with 2008-2009 period in ICU and ER, and the case-control analysis among all Pseudomonas aeruginosa isolated patients identified that bronchoscopes [risk ratio (RR) 8.25, 95% confidence interval (CI) 1.328-51.26] was one of the most important risk factors for MDRP isolation. Duration from admission to MDRP isolation was significant longer in MDRP-isolated cases (19.82±12.77 d), compared with in non MDRP-isolated controls (11.76±11.69 d: p=0.0453). Our epidemiological analysis suggested the significant risk factors for an MDRP outbreak, and could contribute the estimation of the focus and prevention of future outbreaks.

Is reprocessing after disuse a safety procedure for bronchoscopy?: A cross-sectional study in a teaching hospital in Rome.

A bacteriological assessment of flexible bronchoscopes that were stored after a reprocessing procedure was performed to determine whether reprocessing removes microbiological contamination and whether the instruments could be used safely after extended storage without repeating the disinfection before bronchoscopy. The microbiological quality of manual and automated reprocessed bronchoscopes was examined by collecting a pre-reprocessing and a post-reprocessing liquid sample from the stored instruments' channels. A qualitative microbiological analysis was performed to evaluate bacterial contamination. Among the 264 pre-reprocessing bronchoscopes, 10 were contaminated (13 human flora strains and 1 environmental strain were detected). After reprocessing, 8 were decontaminated and 2 remained contaminated. Furthermore, 12 other bronchoscopes had a new contamination post-reprocessing (11 human flora and 3 environmental strains were detected). In addition, 2 sampled bronchoscopes were contaminated both pre- and posttreatment. Our findings support the suggestion that reprocessing after storage can be avoided in the safe usage of the instrument if earlier decontaminations are performed correctly. Having found that reprocessing could contaminate bronchoscopes, additional studies are needed to identify the risk factors for contamination and avoid controversial suggestions for first-use reprocessing.

Cluster of pseudoinfections with Burkholderia cepacia associated with a contaminated washer-disinfector in a bronchoscopy unit.

In December 2008, bronchoalveolar lavage fluid samples obtained from 3 patients were positive for Burkholderia cepacia complex on culture. Samples obtained from bronchoscopes and rinse-water samples obtained from the washer-disinfector were found to be positive for B. cepacia complex. The cause of this pseudo-outbreak was that the washer-disinfector was installed without the required antibacterial filter.