Lessons from outbreaks associated with bronchoscopy

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.

A review of waste-to-hydrogen conversion technologies for solid oxide fuel cell (SOFC) applications: Aspect of gasification process and catalyst development

In the twenty-first century, there has been an increase in energy demand and waste production, due to the rising population of the world. One good approach for satisfying the energy demand and overcoming the waste management issues is to convert waste to energy. Additionally, using waste biomass as the feedstock of waste-to-energy (WtE) conversion methods makes them renewable and green and also helps the environmental challenges and reduces the emission of greenhouse gases (GHGs). Gasification is a thermochemical WtE route, which can produce hydrogen-rich gaseous biofuel called synthetic gas (syngas), from wastes. In this paper, different aspects of gasification process are reviewed with greater focus on catalyst usage. Syngas processing steps, which increase the quality and H₂ content of the syngas to form bio-hydrogen, are discussed. Solid oxide fuel cell (SOFC) technology is one of the most promising techniques of renewable energy production due to their environmental cleanness characteristics and high efficiencies. Thus, one of the best ways to exploit the energy content of the bio-hydrogen product of gasification is to employ it in a SOFC. Therefore, waste biomass gasification process can be integrated with SOFCs to build high efficiency systems for production of clean and renewable energy from waste, which are called integrated gasification fuel cell (IGFC) systems. These systems provide the opportunity of further upgrading of syngas inside the SOFC. In this paper, we are going to briefly discuss fuel cell technology (especially SOFCs) and review SOFC applications from the aspect of integration with gasification process (IGFC system). Finally, the impacts and issues of gasification process and SOFC technology are considered.

Infection Prevention in the Neonatal Intensive Care Unit

Although many aspects of infection prevention and control (IPC) mirror institutional efforts, optimization of IPC practices in the neonatal intensive care unit requires careful consideration of its unique population and environment, addressed here for key IPC domains. In addition, innovative mitigation efforts to address challenges specific to limited resource settings are discussed.

Tuberculosis among prisoners & health care workers

TB in prisons and among HCW is a major public health concern in countries having high burden of disease. Prompt detection of TB is must in prisons by screening on entry, passive screening, mass screening and contact screening via clinical evaluation, smear microscopy and chest X-rays. The new rapid diagnostic methods - True-NAAT, CBNAAT and Line Probe Assay are important tools in the diagnosis. Implementation of effective preventive measures at every steps in various settings, along with airborne infection control and protective measures for staff must be ensured.

Adenovirus pseudo-outbreak associated with bronchoscopy

Introduction and regular application of multiplex polymerase chain reaction analysis of bronchoalveolar specimens for community-acquired respiratory viruses in January 2017 led to the identification of adenovirus in multiple patients in a surgical intensive unit in July 2017, which was attributed to a pseudo-outbreak.

Innovation in surgery/operating room driven by Internet of Things on medical devices

BACKGROUND

With the improvement of sensor technology, the trend of Internet of Things (IoT) is affecting the medical devices. The aim of this study is to verify whether it is possible to "visualize instrument usage in specific procedures" by automatically accumulating the digital data related to the behavior of surgical instruments/forceps in laparoscopic surgery.

METHODS

Five board-certified surgeons (PGY 9-24 years) performed laparoscopic cholecystectomy on 35-kg porcine (n = 5). Radio frequency identifier (RFID) was attached to each forceps with RFID readers installed on the left/right of the operating table. We automatically recorded the behavior by tracking the operator's right/left hands' forceps with RFID. The output sensor was installed in the electrocautery circuit for automatic recordings of the ON/OFF times and the activation time. All data were collected in dedicated software and used for analysis.

RESULTS

In all cases, the behaviors of forceps and electrocautery were successfully recorded. The median operation time was 1828 s (range 1159-2962 s), of which the electrocautery probe was the longest held on the right hand (1179 s, 75%), followed by Maryland dissectors (149 s, 10%), then clip appliers (91 s, 2%). In contrast, grasping forceps were mainly used in the left hand (1780 s, 93%). The activation time of electrocautery was only 8% of the total use and the remaining was mainly used for dissection. These situations were seen in common by all operators, but as a mentor surgeon, there was a tendency to change the right hand's instruments more frequently. The median activation time of electrocautery was 0.41 s, and these were confirmed to be 0.14-0.57 s among the operators.

CONCLUSION

By utilization of IoT for surgery, surgical procedure could be "visualized." This will improve the safety on surgery such as optimal usage of surgical devices, proper use of electrocautery, and standardization of the surgical procedures.

APSIC guidelines for disinfection and sterilization of instruments in health care facilities

Background

The Asia Pacific Society of Infection Control launched its revised Guidelines for Disinfection and Sterilization of Instruments in Health Care Facilities in February 2017. This document describes the guidelines and recommendations for the reprocessing of instruments in healthcare setting. It aims to highlight practical recommendations in a concise format designed to assist healthcare facilities at Asia Pacific region in achieving high standards in sterilization and disinfection.

Method

The guidelines were revised by an appointed workgroup comprising experts in the Asia Pacific region, following reviews of previously published guidelines and recommendations relevant to each section.

Results

It recommends the centralization of reprocessing, training of all staff with annual competency assessment, verification of cleaning, continual monitoring of reprocessing procedures to ensure their quality and a corporate strategy for dealing with single-use and single-patient use medical equipment/devices. Detailed recommendations are also given with respect to reprocessing of endoscopes. Close working with the Infection Prevention & Control department is also recommended where decisions related to reprocessing medical equipment/devices are to be made.

Conclusions

Sterilization facilities should aim for excellence in practices as this is part of patient safety. The guidelines that come with a checklist help service providers identify gaps for improvement to reach this goal.

Electronic supplementary material

The online version of this article (10.1186/s13756-018-0308-2) contains supplementary material, which is available to authorized users.

Outbreak of pulmonary Pseudomonas aeruginosa and Stenotrophomonas maltophilia infections related to contaminated bronchoscope suction valves, Lyon, France, 2014

In April 2014, pulmonary Pseudomonas aeruginosa and Stenotrophomonas maltophilia co-infections potentially related to bronchoscopic procedures were identified in the intensive care units of a university hospital in Lyon, France. A retrospective cohort of 157 patients exposed to bronchoscopes from 1 December 2013 to 17 June 2014 was analysed. Environmental samples of suspected endoscopes were cultured. Bronchoscope disinfection was reviewed. Ten cases of pulmonary P. aeruginosa/S. maltophilia co-infections were identified, including two patients with secondary pneumonia. Eight cases were linked to bronchoscope A1 and two to bronchoscope A2. Cultures deriving from suction valves were positive for P. aeruginosa/S. maltophilia. Exposure to bronchoscopes A1 and A2 was independently coupled with increased risk of co-infection (adjusted odds ratio (aOR) = 84.6; 95% confidence interval (CI): 9.3-771.6 and aOR = 11.8, 95% CI: 1.2-121.3). Isolates from suction valves and clinical samples presented identical pulsotypes. The audit detected deficiencies in endoscope disinfection. No further cases occurred after discontinuation of the implicated bronchoscopes and change in cleaning procedures. This outbreak of pulmonary P. aeruginosa/S. maltophilia co-infections was caused by suction valve contamination of two bronchoscopes of the same manufacturer. Our findings underscore the need to test suction valves, in addition to bronchoscope channels, for routine detection of bacteria.

Enzymes Enhance Biofilm Removal Efficiency of Cleaners

Efficient removal of biofilms from medical devices is a big challenge in health care to avoid hospital-acquired infections, especially from delicate devices like flexible endoscopes, which cannot be reprocessed using harsh chemicals or high temperatures. Therefore, milder solutions such as enzymatic cleaners have to be used, which need to be carefully developed to ensure efficacious performance. In vitro biofilm in a 96-well-plate system was used to select and optimize the formulation of novel enzymatic cleaners. Removal of the biofilm was quantified by crystal violet staining, while the disinfecting properties were evaluated by a BacTiter-Glo assay. The biofilm removal efficacy of the selected cleaner was further tested by using European standard (EN) for endoscope cleaning EN ISO 15883, and removal of artificial blood soil was investigated by treating TOSI (Test Object Surgical Instrument) cleaning indicators. Using the process described here, a novel enzymatic endoscope cleaner was developed, which removed 95% of Staphylococcus aureus and 90% of Pseudomonas aeruginosa biofilms in the 96-well plate system. With a >99% reduction of CFU and a >90% reduction of extracellular polymeric substances, this cleaner enabled subsequent complete disinfection and fulfilled acceptance criteria of EN ISO 15883. Furthermore, it efficiently removed blood soil and significantly outperformed comparable commercial products. The cleaning performance was stable even after storage of the cleaner for 6 months. It was demonstrated that incorporation of appropriate enzymes into the cleaner enhanced performance significantly.

How to Assess Risk of Disease Transmission to Patients When There Is a Failure to Follow Recommended Disinfection and Sterilization Guidelines

Background.

Disinfection and sterilization are critical components of infection control. Unfortunately, breaches of disinfection and sterilization guidelines are not uncommon.

Objective.

To describe a method for evaluating a potential breach of guidelines for high-level disinfection and sterilization of medical devices.

Methods.

The appropriate scientific literature was reviewed to determine the frequency of failures of compliance. A risk assessment model was constructed.

Results.

A 14-step protocol was constructed to aid infection control professionals in the evaluation of potential disinfection and sterilization failures. In addition, a model is presented for aiding in determining how patients should be notified of the potential adverse event. Sample statements and letters are provided for communicating with the public and individual patients.

Conclusion.

Use of a protocol can guide an institution in managing potential disinfection and sterilization failures.

Pseudo-Outbreak ofLegionella pneumophilaSerogroup 8 Infection Associated With a Contaminated Ice Machine in a Bronchoscopy Suite

Objective.

To investigate the marked increase noted over an 8-month period in the number ofLegionella pneumophilaisolates recovered from bronchoalveolar lavage fluid specimens obtained during bronchoscopy in our healthcare system.

Setting.

Bronchoscopy suite that serves a 580-bed tertiary care center and a large, multisite, faculty practice plan with approximately 2 million outpatient visits per year.

Methods.

Cultures of environmental specimens from the bronchoscopy suite were performed, including samples from the air and water filters, bronchoscopes, and the ice machine, with the aim of identifyingLegionellaspecies. Specimens were filtered and acid-treated and then inoculated on buffered charcoal yeast extract agar. Serogrouping was performed on all isolates recovered from patient and environmental samples.

Results.

AUL. pneumophilaisolates recovered from patients were serogroup 8, a serogroup that is not usually recovered in our facility. An epidemiologic investigation of the bronchoscopy suite revealed the ice machine to be contaminated withL. pneumophilaserogroup 8. Patients were exposed to the organism as a result of a recently adopted practice in the bronchoscopy suite that involved directly immersing uncapped syringes of sterile saline in contaminated ice baths during the procedures. At least 1 patient was ill as a result of the pseudo-outbreak. Molecular typing of isolates recovered from patient and environmental samples revealed that the isolates were indistinguishable.

Conclusions.

Extensive cleaning of the ice machine and replacement of the machine's water filter ended the pseudo-outbreak. This episode emphasizes the importance of using aseptic technique when performing invasive procedures, such as bronchoscopies. It also demonstrates the importance of reviewing procedures in all patient areas to ensure compliance with facility policies for providing a safe patient environment.

New developments in reprocessing semicritical items

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (eg, gastrointestinal endoscopes). Such medical devices require minimally high-level disinfection. Because many of these items are temperature sensitive, low-temperature chemical methods must be used rather than steam sterilization. Strict adherence to current guidelines is required because more outbreaks have been linked to inadequately cleaned or disinfected endoscopes undergoing high-level disinfection than any other medical device.

The role of biofilms in reprocessing medical devices

Biofilms are communities of microorganisms within extracellular polymeric material attached to surfaces. Within a biofilm, cells have some protection from drying and other stress factors in their environment, including antimicrobial agents. In this article, the challenges to medical device reprocessing posed by biofilms are addressed. Biofilm formation on reusable medical device surfaces is a risk that can be controlled. By ensuring prompt device cleaning and reprocessing either by high-level disinfection or sterilization and proper drying, biofilms will not have a chance to form. Reusable medical devices like flexible endoscopes that are promptly cleaned and disinfected, rinsed and dried pose little risk to patients.

Reduced turnover times make flexible optical reusable scope with EndoSheath(®) Technology significantly cost-effective

EndoSheath bronchoscopy (Vision Sciences, Inc.) uses a sterile, disposable microbial barrier that may meet the growing needs for safe, efficient, and cost effective flexible bronchoscopy. The purpose of this open-label comparative study was to compare and calculate the costs-per-airway-procedure of the reusable fiberscope when used with and without EndoSheath^® Technology; and to record the turnover time from the completion of the use of each scope until its readiness again for the next use. Seventy-five new patients' airways requiring airway maneuvers and manipulations with Vision Sciences, Inc., reusable fiberscope with EndoSheath^® Technology were evaluated for the costs comparisons with reassessed historical costs data for Olympus scope assisted tracheal intubations. As compared to costs of an intubation ($158.50) with Olympus scope at our institute, the intubation costs with Vision Sciences, Inc., reusable fiberscope with EndoSheath technology was $81.50 (P < 0.001). The mean turnover time was 5.44 min with EndoSheath technology as compared to previously reported 30 min with Olympus fiberscope (P < 0.001). Based on our institutional experience, Vision Sciences, Inc., reusable fiberscope with EndoSheath technology is significantly cost effective as compared to the Olympus scope with significantly improved turnover times.

Better instructions for use to improve reusable medical equipment (RME) sterility

OBJECTIVE

The objective was to evaluate human-factors-based instructional aids on endoscope reprocessing.

BACKGROUND

The project stems from recent failures in reprocessing (cleaning) endoscopes, contributing to the spread of harmful bacterial and viral agents between patients. A previous study discovered three themes that represent a majority of problems: (1) lack of visibility (parts and tools were difficult to identify), (2) high memory demands, and (3) insufficient feedback.

METHOD

In an effort to improve completion rate and reduce error, the authors designed instructional aids utilizing human factors principles that would replace existing manufacturer-provided visual aids. Then, they conducted a usability test, which compared the endoscope reprocessing performance of novices using the standard manufacturer-provided visual aids and the new instructional aids.

RESULTS

Participants in the experimental group successfully completed 87.1% of the reprocessing procedure with the use of the instructional aids, compared to 44.7% in the control group using only existing support materials. Of 60 subtasks, 27 showed significant improvement in completion rates.

CONCLUSION

When given an instructional aid designed with human factors principles, participants were able to more successfully complete the reprocessing task. This resulted in an endoscope that was more likely to be safe for use on patients.

APPLICATION

The human factors design elements utilized to create the instructional aids could be transferred to a dynamic electronic-based system to improve patient safety.

Plumbing of hospital premises is a reservoir for opportunistically pathogenic microorganisms: a review

Several bacterial species that are natural inhabitants of potable water distribution system biofilms are opportunistic pathogens important to sensitive patients in healthcare facilities. Waterborne healthcare-associated infections (HAI) may occur during the many uses of potable water in the healthcare environment. Prevention of infection is made more challenging by lack of data on infection rate and gaps in understanding of the ecology, virulence, and infectious dose of these opportunistic pathogens. Some healthcare facilities have been successful in reducing infections by following current water safety guidelines. This review describes several infections, and remediation steps that have been implemented to reduce waterborne HAIs.

Controlling bacterial contamination of dental impression guns

BACKGROUND

Dental impression material handgun cartridge dispensers are contaminated easily during clinical use. The authors attempted to quantify contamination by bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), of impression guns used in an academic dental clinic after five infection-prevention protocols were followed.

METHODS

The authors obtained samples from four commercially available impression guns at four specific sites (button, handle, latch, trigger) after routine clinical use, disinfection, steam sterilization (also known as autoclaving), steam sterilization followed by use of plastic impression gun covers and steam sterilization followed by use of plastic impression gun covers and disinfection.

RESULTS

The authors found that after routine clinical use, bacteria-including MRSA-heavily contaminated the impression guns. After the impression guns underwent disinfection, there was a 6 percent decrease in bacterial counts. The use of steam sterilization achieved sterility without harming the impression guns. Use of steam-sterilized impression guns with plastic impression gun covers decreased bacterial isolates by approximately 60 percent. Use of steam-sterilized impression guns plus covers and disinfection resulted in an approximately 95 percent reduction in contamination.

CONCLUSIONS

The use of common infection-prevention methods appears to reduce the bacterial counts, including those of MRSA. Bacterial contamination was lowest after steam sterilization, followed by the use of plastic impression gun covers and disinfection.

CLINICAL IMPLICATIONS

Use of contaminated impression guns on successive patients could increase the risk of causing cross-transmission of disease. The use of sterilization, plus plastic impression gun covers and disinfection, for impression guns after each use could be an effective and practical infection-control method for dental practices.

National athletic trainers' association position statement: skin diseases

OBJECTIVE

To present recommendations for the prevention, education, and management of skin infections in athletes.

BACKGROUND

Trauma, environmental factors, and infectious agents act together to continually attack the integrity of the skin. Close quarters combined with general poor hygiene practices make athletes particularly vulnerable to contracting skin diseases. An understanding of basic prophylactic measures, clinical features, and swift management of common skin diseases is essential for certified athletic trainers to aid in preventing the spread of infectious agents.

RECOMMENDATIONS

These guidelines are intended to provide relevant information on skin infections and to give specific recommendations for certified athletic trainers and others participating in athletic health care.

Hospital epidemiology and infection control in acute-care settings

Health care-associated infections (HAIs) have become more common as medical care has grown more complex and patients have become more complicated. HAIs are associated with significant morbidity, mortality, and cost. Growing rates of HAIs alongside evidence suggesting that active surveillance and infection control practices can prevent HAIs led to the development of hospital epidemiology and infection control programs. The role for infection control programs has grown and continues to grow as rates of antimicrobial resistance rise and HAIs lead to increasing risks to patients and expanding health care costs. In this review, we summarize the history of the development of hospital epidemiology and infection control, common HAIs and the pathogens causing them, and the structure and role of a hospital epidemiology and infection control program.

Exploring Human Factors in Endoscope Reprocessing

The goal of this research is to study the human factors that influence the reprocessing of flexible endoscopes. This paper will report on the preliminary findings from a heuristic evaluation of current reprocessing procedures from an ongoing multi-method study and will discuss the implications of the results for future research purposes.

Controlling antimicrobial resistance in the hospital

Most evidence-based methods to control the spread of antimicrobial resistance have been developed and applied to the hospital setting. Strategies to control the emergence and spread of antimicrobial resistance in hospitals can be categorized as either infection control or antibiotic stewardship strategies. Infection control is the discipline focused on preventing the spread of infections within the health care setting; antibiotic stewardship can help minimize the emergence of multidrug-resistant organisms by promoting prudent use of antibiotics. This article describes different infection control and antibiotic management strategies that can be used to control antimicrobial resistance in hospital settings.

An outbreak of Pseudomonas aeruginosa infections following thoracic surgeries occurring via the contamination of bronchoscopes and an automatic endoscope reprocessor

An outbreak of Pseudomonas aeruginosa infections occurred after thoracic surgeries performed between May and June 2003. Clinical data of seven patients were reviewed and the fact was revealed that bronchoscopes were used during endotracheal intubation for one-lung ventilation in most patients. P. aeruginosa was recovered from the sputum of these patients at a very early stage post-operation. Environmental samples from bronchoscopes and an automated endoscope reprocessor (AER) were cultured and P. aeruginosa strains were recovered from all of them. All of these strains were confirmed to be identical by pulsed-field gel electrophoresis (PFGE). Inspection of the sterilization cycles of bronchoscopes revealed inappropriate management of bronchoscopes and a flaw in the AER; once its detergent tank was contaminated, it was not possible to disinfect it. After all the bronchoscopes had been disinfected, and the washing machine had been remodeled, with the washing process confirmed to be appropriate, the outbreak finally ended. This outbreak had two causes, a flaw in the AER and inappropriate disinfection procedures. Outbreaks associated with bronchoscopic examinations have been reported elsewhere. Bronchoscopes are widely used to facilitate endotracheal intubation, especially for one-lung anesthesia. Although they are used for only a short time during anesthetic procedures, we should handle them more carefully.

Developing a broader approach to management of infection control breaches in health care settings

Our experiences with health departments and health care facilities suggest that questions surrounding instrument reprocessing errors and other infection control breaches are becoming increasingly common. We describe an approach to management of these incidents that focuses on risk of bloodborne pathogen transmission and the role of public health and other stakeholders to inform patient notification and testing decisions.

Decontamination and traceability of flexible endoscopes

The Ear, Nose and Throat (ENT) and Oral and Maxillofacial Surgery (OMFS) departments at Glasgow's Southern General Hospital use their 21 flexible endoscopes on a daily basis for a variety of surgical and anaesthetic procedures, including difficult intubations and the examination of the throat and airway. This article will examine the possible risks to the patient with these procedures and some cost-effective methods of minimising those risks within these departments.

Use of germicides in the home and the healthcare setting: is there a relationship between germicide use and antibiotic resistance?

BACKGROUND

The spread of antibiotic-resistant pathogens represents an increasing threat in healthcare facilities. Concern has been expressed that the use of surface disinfectants and antiseptics may select for antibiotic-resistant pathogens.

OBJECTIVE

To review the scientific literature on whether there is a link between use of germicides (ie, disinfectants and antiseptics) and bacterial resistance to antibiotics. In addition, we will review whether antibiotic-resistant bacteria exhibit altered susceptibility to germicides that are recommended for use as disinfectants or antiseptics.

DESIGN

A review of the appropriate scientific literature.

RESULTS

In the laboratory, it has been possible to develop bacterial mutants with reduced susceptibility to disinfectants and antiseptics that also demonstrate decreased susceptibility to antibiotics. However, the antibiotic resistance described was not clinically relevant because the test organism was rarely a human pathogen, the altered level of antimicrobial susceptibility was within achievable serum levels for the antibiotic, or the antibiotic tested was not clinically used to treat the study pathogen. Similarly, wild-type strains with reduced susceptibility to disinfectants (principally, quaternary ammonium compounds) and antiseptics (principally, triclosan) have been reported. However, because the concentration of disinfectants used in the healthcare setting greatly exceeds the concentration required to kill strains with reduced susceptibility to disinfectants, the clinical relevance of these observations is questionable.

CONCLUSION

To date, there is no evidence that using recommended antiseptics or disinfectants selects for antibiotic-resistant organisms in nature. Disinfectants and antiseptics should be used when there are scientific studies demonstrating benefit or when there is a strong theoretical rationale for using germicides.

Outbreaks of contaminated broncho-alveolar lavage related to intrinsically defective bronchoscopes

From 5 March 2001 to 19 October 2001, outbreaks of broncho-alveolar lavage (BAL) contamination with Enterobacteraceae were detected in our 700-bed institution. We report the investigation of these outbreaks. A case was defined as the occurrence of pairs of specific Enterobacteraceae in BAL specimens among any patients who underwent bronchoscopy in the respiratory unit during the period of the outbreak. Contamination was identified in 117 BAL samples during three outbreaks among 418 patients, and was associated with bronchoscopes 11 and 12 (P<0.001). The other five devices in use were not linked with the outbreaks. During the first outbreak, particular pairs of micro-organisms were associated with a specific bronchoscope (Klebsiella pneumoniae/Proteus vulgaris with bronchoscope 11, and Morganella morganii/Proteus mirabilis with bronchoscope 12). Cultures of sputa from two patients also yielded M. morganii some days after bronchoscopic examination. Isolates from contaminated BAL samples and bronchoscope 11 had similar patterns by pulsed-field gel electrophoresis. No further cases occurred after removal of the implicated bronchoscopes. No deficiencies in disinfection procedures were detected and the source of contamination was found to be a loose port of the biopsy channel of the bronchoscope. Our findings underscore the urgent need to test bronchoscopic samples regularly and to improve the design and structure of bronchoscopes.

Disinfection and sterilization in health care facilities: what clinicians need to know

All invasive procedures involve contact between a medical device or surgical instrument and a patient's sterile tissue or mucous membranes. A major risk of all such procedures is the introduction of pathogenic microbes that could lead to infection. Failure to properly disinfect or sterilize reusable medical equipment carries a risk associated with breach of the host barriers. The level of disinfection or sterilization is dependent on the intended use of the object: critical items (such as surgical instruments, which contact sterile tissue), semicritical items (such as endoscopes, which contact mucous membranes), and noncritical items (such as stethoscopes, which contact only intact skin) require sterilization, high-level disinfection, and low-level disinfection, respectively. Cleaning must always precede high-level disinfection and sterilization. Users must consider the advantages and disadvantages of specific methods when choosing a disinfection or sterilization process. Adherence to these recommendations should improve disinfection and sterilization practices in health care facilities, thereby reducing infections associated with contaminated patient-care items.

Antibiotic susceptibility of glutaraldehyde-tolerant Mycobacterium chelonae from bronchoscope washing machines

BACKGROUND

Contamination of bronchoalveolar lavage fluid is a major problem in the world. Although 2% glutaraldehyde (GA) is widely used as a disinfectant for bronchoscope cleaning, recently, GA-tolerant mycobacteria have been isolated, which makes this problem more complicated.

METHODS

We studied the susceptibility to GA and antibiotics of mycobacteria isolated from bronchoscope washing machines in our hospital. We also studied the minimum inhibitory concentrations of GA and antibiotics with pump inhibitors.

RESULTS

Twenty-nine mycobacteria were isolated, of which 26 were Mycobacterium chelonae. Among 18 isolates of M chelonae, excluding 8 isolates in which some results were not reproducible, 50% (9 of 18) were 2% GA-tolerant. One hundred percent (9 of 9) of the GA-tolerant isolates and 11% (1 of 9) of the GA-sensitive isolates were either resistant or intermediately resistant to 2 or 3 classes of antibiotics. Efflux pump inhibitors did not influence the susceptibility to GA and antibiotics.

CONCLUSIONS

It was suggested that there might be an association of GA tolerance with antibiotic resistance in M chelonae. There may a different mechanism(s) other than that involving efflux pumps with regard to GA tolerance and antibiotic resistance in M chelonae. When bronchoscopy-related mycobacterial infections are suspected, physicians and clinical microbiologists should exercise care in handling GA-tolerant mycobacteria, which may be resistant to multiple antibiotics.

Reprocessing endoscopes: United States perspective

Endoscopes are used frequently for the diagnosis and therapy of medical disorders. For example, greater than 10000000 gastrointestinal endoscopic procedures are performed each year in the United States. Failure to employ appropriate cleaning and disinfection/sterilization of endoscopes has been responsible for multiple nosocomial outbreaks and serious, sometimes life-threatening, infections. Flexible endoscopes, by virtue of the site of use, have a high bioburden of microorganisms after use. The bioburden found on flexible gastrointestinal endoscopes following use has ranged from 10(5) to 10(10)CFU/ml, with the highest levels being found in the suction channels. Cleaning dramatically reduces the bioburden on endoscopes. Several investigators have shown a mean log(10) reduction factor of 4 (99.99%) in the microbial contaminants with cleaning alone. Cleaning should be done promptly following each use of an endoscope to prevent drying of secretions, allow removal of organic material, and decrease the number of microbial pathogens. Because the endoscope comes into intimate contact with mucous membranes, high-level disinfection is the reprocessing standard after each patient use. High-level disinfection refers to the use of a disinfectant (e.g., FDA-cleared chemical sterilant or high-level disinfectant) that inactivates all microorganisms (i.e., bacteria, viruses, fungi, mycobacteria) but not high levels of bacterial spores. The disinfection process requires immersion of the endoscope in the high-level disinfectant and ensuring all channels are perfused for the approved contact time (e.g., for ortho-phthaladehyde this is 12 min in the US). Following disinfection, the endoscope and channels are rinsed with sterile water, filtered water, or tapwater. The channels are then flushed with alcohol and dried using forced air. The endoscope should be stored in a manner that prevents recontamination. A protocol that describes the meticulous manual cleaning process, the appropriate training and evaluation of the reprocessing personnel, and a quality assurance program for endoscopes should be adopted and enforced by each unit performing endoscopic reprocessing.

Bronchoscope Reprocessing and Infection Prevention and Control

BACKGROUND

It has been recommended that bronchoscopists familiarize themselves with national recommendations for bronchoscope reprocessing practices, but the extent of guideline awareness is unclear.

METHODS

We distributed a survey to practicing bronchoscopists at two meetings. Questions addressed infection control issues related to bronchoscopy and specific reprocessing recommendations.

RESULTS

A total of 46 surveys were completed by medical directors of bronchoscopy suites (26%) and attending bronchoscopists (74%) who had graduated from medical school a median of 22 years ago and performed a median of 19 procedures per month. Sixty-five percent of respondents, including 55% of directors, were not familiar with national reprocessing recommendations, and 39% did not know the approach to reprocessing at their own institution. Respondents who did > 20 procedures per month trended toward being more likely to be aware of guidelines (54% vs 26%, p = 0.09) and were less likely to answer "do not know" to more than one question about specific reprocessing details (25% vs 70%, p = 0.003). Seventy-eight percent of respondents did not know local practices for at least one of the reprocessing details. Forty-six percent of respondents stated their institutions followed recommendations that records be kept of the specific bronchoscope used in each case.

CONCLUSIONS

Many experienced bronchoscopists are unfamiliar with national guidelines and local practices related to bronchoscope reprocessing. Publication of bronchoscope-specific, comprehensive reprocessing guidelines in the pulmonary literature may help increase familiarity with this crucial process.

Epidemiology and Prevention of Infections Related to Endoscopy

Contaminated endoscopes are the most common cause of device-related nosocomial outbreaks in the United States. Because almost all outbreaks are related to breaches in reprocessing techniques, it is crucial that endoscope cleaning and disinfection are performed carefully. Key elements that should be emphasized are availability of and adherence to guidelines, thorough staff training, and ensuring proper equipment is used in the reprocessing. Encouraging endoscopists to notify infection control when they see unexpected postprocedure complications and document which endoscopes are used in each case are key elements in limiting the impact of outbreaks.

Cluster of Trichosporon mucoides in children associated with a faulty bronchoscope

BACKGROUND

Several outbreaks of Pseudomonas aeruginosa infection associated with a specific model of fiberoptic bronchoscope have been reported. In a 3-week period in September 2000, we noticed an increased number of Trichosporon mucoides isolates recovered from bronchoalveolar lavage (BAL) specimens collected at our hospital. We investigated the circumstances surrounding these isolates.

METHODS

Outbreak investigation was conducted, and the medical records of the affected patients were reviewed retrospectively for evidence of positive cultures for T. mucoides from BAL specimens. Specimens collected during the investigation were inoculated onto fungal culture medium and yeasts were identified with API-20C (BioMèrieux-Vitek).

RESULTS

During the 3-week period BAL specimens from six patients yielded growth of T. mucoides. These six high risk patients had emergency bronchoscopy performed as a workup for pneumonia and/or respiratory distress. A Model BF XP-40 bronchoscope (Olympus) had been used in all six patients. Cultures of the bronchoscope (external body and the lumen), bronchoscope disinfector, 2% glutaraldehyde disinfecting solution and water filters/supply were performed. Only fluid from the bronchoscope lumen yielded growth of T. mucoides. Air sample cultures of the bronchoscopy suites were negative. Medical records review disclosed that affected patients were not readmitted with infection with T. mucoides and had no adverse outcomes. The bronchoscope was removed from service and returned to the manufacturer.

CONCLUSION

Routine surveillance and aggressive investigation identified persistent T. mucoides contamination of one bronchoscope. The bronchoscope manufacturer later recalled the BF XP-40 model for corrective revision.

Pseudomonas aeruginosa and Serratia marcescens contamination associated with a manufacturing defect in bronchoscopes

BACKGROUND

Several outbreaks and pseudo-outbreaks of Pseudomonas aeruginosa and Serratia marcescens infections associated with bronchoscopy have been reported. We conducted an investigation of P. aeruginosa and S. marcescens isolates related to bronchoscopy at a community hospital.

METHODS

We reviewed the records of all bronchoscopic procedures at the community hospital from July to October 2001. Environmental samples were obtained. Pulsed-field gel electrophoresis (PFGE) was performed on isolates of P. aeruginosa.

RESULTS

From July 1 to October 31, 2001, 66 bronchoscopic procedures were performed in 60 patients, and 43 specimens were obtained for bacterial culture; 20 of the specimens (47 percent) were positive for P. aeruginosa. Six (30 percent) of the specimens that were positive for P. aeruginosa also yielded S. marcescens. All 20 P. aeruginosa isolates were associated with procedures performed with three of four new bronchoscopes from the same manufacturer. Contrary to manufacturing specifications, the biopsy-port caps on all four bronchoscopes were easily removable, and P. aeruginosa was cultured from the biopsy ports of the three implicated bronchoscopes. The PFGE patterns of P. aeruginosa isolates from the bronchoscopes, patients, and two environmental samples were indistinguishable. One patient was hospitalized with P. aeruginosa pneumonia 11 days after bronchoscopy. The manufacturer reported a design change instituted in 1997, and production problems may have resulted in the distribution of bronchoscopes that did not meet specifications.

CONCLUSIONS

We documented contamination of bronchoscopes with P. aeruginosa and S. marcescens and possible infection of patients at a community hospital as a result of the inadequate disinfection of bronchoscopes because of a manufacturing defect.

Cleaning efficacy of nine different cleaners in a washer-disinfector designed for flexible endoscopes

Studies on processing endoscopes usually involve the combined cleaning and disinfecting activity. We compared nine cleaning agents designed for automatic processing for cleaning efficacy alone using soft and hard water as controls in 12 different processes in a washer-disinfector. Experiments were performed according to the German Endoscopy Working Group recommendations using transparent Teflon tubes (internal diameter 2mm, length 2m) as test pieces. For each test three pieces contaminated with a blood/test soil containing Enterococcus faecium were used; two for the test and one as a control; each test was repeated three times. Tests were run according to the manufacturer's instructions. Test pieces were assessed visually and microbiologically [log(10) reduction factors (RF) vs. untreated controls]. Soft water alone gave poor visible cleanliness and an RF of 0.3 (SD 0.2), while hard water produced adequate visible cleanliness and an RF of 1.2 (SD 1.0). Five processes gave better visible cleanliness than soft water, but only three were better than hard water. Six processes were worse than soft water and five worse than hard water. Nine processes gave a better microbiological reduction factor than soft water, but the difference was only statistically significant in three. Only one process yielded a significantly higher RF than hard water; three were significantly worse. None of the cleaning processes reached the RF of 4 specified in the US regulations. This study confirms the variability of cleaning processes to dissolve blood residues and reduce the bioburden. We do not recommend abandoning cleaning agents, but suggest that further research is needed to clarify the relationships between washer-disinfectors, cleaning agents, and cleaning performance.