Contamination Of Bronchoscopes Research Articles

POCT Detection of Pseudomonas aeruginosa by PGM and Application of Preventing Nosocomial Infection of Bronchoscopy.

The primary pathogen responsible for bronchoscope contamination is Pseudomonas aeruginosa. Conventional techniques for bronchoscopy disinfection and pathogen identification methods are characterized by time-consuming and operation complexly. The objective of this research is to establish a prompt and precise method for the identification of Pseudomonas aeruginosa, with the ultimate goal of mitigating the risk of nosocomial infections linked to this pathogen. The magnetic nanoparticles (MNPs) were synthesized in a single step, followed by the optimization of the coating process with antibodies and invertase to produce the bifunctionalized IMIc. Monoclonal antibodies were immobilized on microplates for the specific capture and enrichment of Pseudomonas aeruginosa. Upon the presence of Pseudomonas aeruginosa, the monoclonal antibodies, the test sample, and the IMIc formed sandwich structures. The subsequent addition of a sucrose solution allowed for the detection of glucose produced through invertase hydrolysis by a personal glucose meter, enabling quantitative assessment of Pseudomonas aeruginosa concentration. TEM image demonstrates that the MNPs exhibit a consistent spherical shape. NTA determined that the grain diameter of magnetic nanoparticles was 200 nm. FTIR spectrum revealed the successful modification of two carboxyl groups on the MNPs. The optimization of the incubation pH of the microplate-coated antibody was 7. The optimization of the incubation time of the microplate-coated antibody was 2 h. The optimization of the ligation pH for the polyclonal antibody was 5. Reaction times of polyclonal antibodies linked to magnetic beads was 1 h. The pH of invertase linked by magnetic beads was 4. This article presents a novel qualitative and quantitative immunoassay for point-of-care monitoring of P. aeruginosa utilizing PGM as a readout. The PGM represents a convenient and accurate quantitative detection method suitable for potential clinical diagnostic applications.

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

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. We evaluated the impact of routine microbiological surveillance and audits of cleaning/disinfection practices on contamination rates of reprocessed bronchoscopes. 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. 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. 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.

An investigation of Stenotrophomonas maltophilia-positive culture caused by fiberoptic bronchoscope contamination

BackgroundStenotrophomonas maltophilia (SMA) is present in hospital environments and has been one of the pathogens that cause nosocomial contamination and infections. To investigate the occurrence of Stenotrophomonas maltophilia (SMA) in bronchoscope lavage fluid (BALF) among 25 cases treated in the Division of Infection and to trace the contamination source and transmission route.Methods25 cases of SMA positive BALF occurring from May 11 to August 10, 2018 were tested for drug sensitivity. Environmental hygiene conditions were investigated to identify the source of contamination and the route of transmission.ResultsBALF associated SMA was in all cases sensitive to minocycline, levofloxacin and chloramphenicol and resistant to ceftazidime and imipenem. 92.3% of samples were sensitivity to compound sulfamethoxazole. Investigation of environmental hygiene parameters revealed SMA growing on the inner wall of the fiberoptic bronchoscope as a likely source of contamination.ConclusionIncomplete cleaning and sterilization of the fiberoptic bronchoscope led to SMA nosocomial contamination. Strict sterilization procedures are required to prevent and control nosocomial contamination.

Bacterial Topography of the Healthy Human Lower Respiratory Tract.

ABSTRACTAlthough culture-independent techniques have refuted lung sterility in health, controversy about contamination during bronchoscope passage through the upper respiratory tract (URT) has impeded research progress. We sought to establish whether bronchoscopic sampling accurately reflects the lung microbiome in health and to distinguish between two proposed routes of authentic microbial immigration, (i) dispersion along contiguous respiratory mucosa and (ii) subclinical microaspiration. During bronchoscopy of eight adult volunteers without lung disease, we performed seven protected specimen brushings (PSB) and bilateral bronchoalveolar lavages (BALs) per subject. We amplified, sequenced, and analyzed the bacterial 16S rRNA gene V4 regions by using the Illumina MiSeq platform. Rigorous attention was paid to eliminate potential sources of error or contamination, including a randomized processing order and the inclusion and analysis of exhaustive procedural and sequencing control specimens. Indices of mouth-lung immigration (mouth-lung community similarity, bacterial burden, and community richness) were all significantly greater in airway and alveolar specimens than in bronchoscope contamination control specimens, indicating minimal evidence of pharyngeal contamination. Ecological indices of mouth-lung immigration peaked at or near the carina, as predicted for a primary immigration route of microaspiration. Bacterial burden, diversity, and mouth-lung similarity were greater in BAL than PSB samples, reflecting differences in the sampled surface areas. (This study has been registered at ClinicalTrials.gov under registration no. NCT02392182.)

3-5 気管支鏡の抗酸菌汚染対策( 第29回日本呼吸器内視鏡学会総会)

3-5 気管支鏡の抗酸菌汚染対策( 第29回日本呼吸器内視鏡学会総会)

Mycobacterial contamination of bronchoscopes: Challenges and possible solutions in low resource settings

The use of bronchoscopes has increased in tuberculosis (TB) diagnostics to circumvent the diagnostic challenges that are associated with low sputum volume and smear-negative TB. In healthcare facilities situated in low income countries that have a high burden of TB, adequate decontamination of bronchoscopes is a challenge and often overlooked to save on time and costs. This amplifies the risk of outbreaks and pseudo-outbreaks due to Mycobacterium tuberculosis and nontuberculosis mycobacteria. In this minireview, we review published literature of contaminated bronchoscopes causing pseudo-outbreaks of M. tuberculosis and nontuberculosis mycobacteria in an effort to determine common sources, and possible mitigation strategies in low-resource settings.

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.

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. To describe a pseudooutbreak of M abscessus subsp bolletii in an endoscopy and bronchoscopy unit. 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. 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. 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.

Outbreak of Pseudomonas aeruginosa Infection Associated With Contamination of a Flexible Bronchoscope

A cluster of patients with respiratory cultures positive for Pseudomonas aeruginosa with a unique antibiogram was observed during June and July 2007 at a 1,000-bed urban teaching hospital in Atlanta, Georgia. These P. aeruginosa isolates were recovered from bronchoscopically obtained specimens. A cross-sectional study was performed to assess whether the cluster was associated with exposure to a particular bronchoscope (B1); cultures from specimens from the bronchoscopes and the environment were obtained, and the P. aeruginosa isolate type was determined using pulsed-field gel electrophoresis (PFGE). Records of patients exposed to B1 during the cluster period were reviewed. Twelve patients with a culture positive for P. aeruginosa with the unique susceptibility pattern were identified in June-July 2007. No cases were documented from March 1 through May 31, 2007. Culture specimens obtained from B1 after high-level disinfection revealed P. aeruginosa, prompting removal of B1 from service on July 23, 2007. No cases occurred after that date. Eleven (55%) of 20 patients who were exposed to B1 during the cluster period had a culture positive for P. aeruginosa, compared with 1 (2%) of 53 patients who were exposed to other bronchoscopes (P < .001). PFGE patterns for P. aeruginosa isolates obtained from case patients and from B1 were identical. An engineering evaluation of B1 documented several internal damages. Two (10.5%) of 19 patients exposed to B1 during the cluster period may have developed P. aeruginosa infection following exposure to B1. An outbreak or pseudo-outbreak of P. aeruginosa infection occurred in association with use of a damaged bronchoscope. Periodic engineering maintenance may be needed to prevent bronchoscope contamination that is resistant to high-level disinfection.

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.

Pseudo-outbreak of Stenotrophomonas maltophilia Due to Contamination of Bronchoscope

We noticed an abrupt increase in the isolation of Stenotrophomonas maltophilia from bronchoalveolar lavage (BAL) specimens collected at Chosun University Hospital. We performed surveillance cultures in order to identify the source of what appeared to be a pseudo-outbreak. To investigate a possible nosocomial outbreak of S. maltophilia, we performed culture of 11 environmental specimens obtained from a bronchoscopy room and two bronchoscopes. Pulsed-field gel electrophoresis (PFGE) was used to examine the genetic relatedness among the strains of S. maltophilia recovered from BAL specimens of 3 patients and 1 environmental sample, as well as 9 unrelated strains of S. maltophilia as a control. During a 7 day-period in March 2006, S. maltophilia was isolated from the BAL specimens of 7 of 13 (54%) patients, compared to only 5 of 188 (2.6%) patients during the 6-month period prior to that period. S. maltophilia was isolated from 1 of the 11 environmental samples, which was obtained from a fiberoptic bronchoscope suction channel. All 7 patient isolates and one environmental isolate exhibited similar antibiotic susceptibility patterns. PFGE analysis of the genomic DNA from epidemic strains demonstrated an identical banding pattern, whereas each of epidemiologically unrelated strains showed a unique electrophoretic pattern. Apparently one of the hospital bronchoscopes became contaminated with S. maltophilia during a bronchoscopic procedure. It is likely that subsequent specimen contamination occurred because the bronchoscope had been inadequately cleaned and disinfected. The pseudo-outbreak was controlled successfully by removing the source of infection.

American College of Chest Physicians and American Association for Bronchology Consensus Statement: Prevention of Flexible Bronchoscopy-Associated Infection

American College of Chest Physicians and American Association for Bronchology Consensus Statement: Prevention of Flexible Bronchoscopy-Associated Infection

Unusual implication of biopsy forceps in outbreaks of Pseudomonas aeruginosa infections and pseudo-infections related to bronchoscopy

Between January and April 2003, a sudden increase in positive respiratory tract specimens for Pseudomonas aeruginosa was observed in an intensive care unit of the University Teaching Hospital of Montpellier, France. Most of the strains were cultured from bronchoalveolar lavage fluid samples, suggesting that bronchoscopic procedures could be implicated. The relationships between isolates were investigated by antibiotyping and pulsed-field gel electrophoresis. Both phenotypic and molecular markers allowed identification of two consecutive nosocomial outbreaks of respiratory infections related to two different bronchoscopes. These two outbreaks implicated nine and seven patients, respectively. Four of these 16 patients had true infections and recovered with antibiotic therapy. Inspection of both bronchoscopes revealed a damaged internal channel caused by defective biopsy forceps. These defects led to improper cleaning and disinfection of the bronchoscopes despite adherence to all current reprocessing procedures. The two outbreaks were controlled after replacing the inner channels of the bronchoscopes and switching from use of re-usable to disposable biopsy forceps. These outbreaks emphasize the need to establish surveillance procedures for detecting contamination of bronchoscopes, and the importance of recording each endoscopic procedure to facilitate further investigations if needed.

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

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. 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. 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. 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.

Avaliação do risco de contaminação por bactérias, no paciente submetido à broncoscopia, após o reprocessamento do broncoscópio

Introdução: A broncoscopia é um procedimento diagnóstico e terapêutico realizado com a introdução nas vias aéreas de um tubo flexível que permite visualizar até as menores delas. Para evitar ou reduzir o risco de infecções, o broncoscópio deve ser adequadamente desinfetado com, pelo menos, desinfecção de alto nível. Objetivo: Verificar se há risco de contaminação bacteriana para os pacientes submetidos à broncoscopia do Hospital São Paulo da Unifesp, Estado de São Paulo. Métodos: No período de 1997 a 1998, o reprocessamento do broncoscópio incluiu limpeza e enxágüe com água estéril ou potável, seguida de rinsagem com glutaraldeído a 2% por 20 minutos, novo enxágüe com água estéril ou potável e rinsagem com álcool etílico a 70% e secagem com ar forçado pelo canal de sucção. Foram colhidas amostras de 65 pacientes para exames microbiológicos, instalando-se soro fisiológico estéril pelo canal de sucção do broncoscópio. Resultados: Após o reprocessamento foram encontrados nas amostras Staphylococcus epidermidis, Enterobacter sp, Acinetobacter baumanni, Streptococcus viridans, Staphylococcus aureus, Streptococcus beta hemoliticus A, Staphylococcus coagulase negativa e em cinco amostras houve crescimento de microbactéria na cultura. Conclusões: A desinfecç ão do broncoscópio com glutaraldeído a 2% não foi suficiente para garantir a desinfecção do aparelho e a presença de Staphylococcus epidermidis indica que houve contaminação do broncoscópio pela manipulação após a desinfecção.

Contamination of bronchoscopes with Mycobacterium tuberculosis and successful sterilization by low-temperature hydrogen peroxide plasma sterilization

Background: The transmission of mycobacteria by bronchoscopes has been reported several times in the last years. To explore methods to prevent transmission of tuberculosis in this way, we sterilized contaminated bronchoscopes with low-temperature hydrogen peroxide gas plasma sterilization. Methods: Bronchoscopes were contaminated with Mycobacterium tuberculosis and decontaminated with a washer/disinfecter (“normal washing”). Some were additionally disinfected with glutaraldehyde (“intensive washing”). Afterward the bronchoscopes were sterilized by low-temperature hydrogen peroxide plasma sterilization. Results: After normal washing, 8/17 samples had positive results by culture, and 7/17 had positive results by nucleic acid amplification technique. After intensive washing, all samples had negative results by culture, and 10/25 had positive results by nucleic acid amplification technique; after sterilization with low-temperature hydrogen peroxide plasma sterilization, all samples had negative results by culture and nucleic acid amplification technique. Conclusion: Washing of bronchoscopes, as performed normally, is not sufficient for decontamination of bronchoscopes. Additional disinfection is recommended. If the nucleic acid amplification technique is used for diagnostic procedures, sterilization by low-temperature hydrogen peroxide plasma sterilization is recommended to avoid false-positive results.

Mycobacterium immunogenum sp. nov., a novel species related to Mycobacterium abscessus and associated with clinical disease, pseudo-outbreaks and contaminated metalworking fluids: an international cooperative study on mycobacterial taxonomy.

PCR-restriction enzyme pattern analysis of a 439 bp hsp65 gene segment identified 113 unique isolates among non-pigmented rapidly growing mycobacteria (RGM) from clinical and environmental sources that failed to match currently recognized species patterns. This group represented 40% of isolates recovered from bronchoscope contamination pseudo-outbreaks, 0% of disease-associated nosocomial outbreaks and 4% of routine clinical isolates of the Mycobacterium abscessus/Mycobacterium chelonae group submitted to the Mycobacteria/Nocardia laboratory for identification. It is grouped within the Mycobacterium fortuitum complex, with growth in less than 7 d, absence of pigmentation, positive 3-d arylsulfatase reaction and growth on MacConkey agar without crystal violet. It exhibited overlapping biochemical, antimicrobial susceptibility and HPLC characteristics of M. abscessus and M. chelonae. By 16S rRNA gene sequencing, these isolates comprised a homogeneous group with a unique hypervariable region A sequence and differed by 8 and 10 bp, respectively, from M. abscessus and M. chelonae. Surprisingly, this taxon contained two copies of the ribosomal operon, compared with single copies in the two related species. By DNA-DNA hybridization, this new group exhibited <30% homology with recognized RGM species. The name Mycobacterium immunogenum sp. nov. is proposed for this new taxon.

Nosocomial transmission of imipenem-resistant Pseudomonas aeruginosa following bronchoscopy associated with improper connection to the Steris System 1 processor.

To assess nosocomial transmission of imipenem-resistant Pseudomonas aeruginosa (IRPA) following bronchoscopy during August through October 1998. Traditional and molecular epidemiological investigation of a case series. University-affiliated community hospital. 18 patients with IRPA bronchial-wash isolates. We reviewed clinical data, performed environmental cultures and molecular analysis of all IRPA isolates, and observed disinfection of bronchoscopes. Of 18 patients who had IRPA isolated from bronchoscopic or postbronchoscopic specimens, 13 underwent bronchoscopy for possible malignancy or undiagnosed pulmonary infiltrates. Following bronchoscopy, 3 patients continued to have IRPA isolated from sputum and demonstrated clinical evidence of infection requiring specific antimicrobial therapy. The remaining 15 patients had no further IRPA isolated and remained clinically well 3 months following bronchoscopy. Pulsed-field gel electrophoresis revealed that all strains except one were >95% related. STERIS SYSTEM 1 had been implemented in July 1998 as an automatic endoscope reprocessor (AER) for all endoscopes and bronchoscopes. Inspection of bronchoscope sterilization cycles revealed incorrect connectors joining the bronchoscope suction channel to the STERIS SYSTEM 1 processor, obstructing peracetic acid flow through the bronchoscope lumen. No malfunction warning was received, and spore strips remained negative. The similarity of diverse connectors and limited training by the manufacturer regarding AER for bronchoscopes were the two factors responsible for the outbreak. Appropriate connections were implemented, and there was no further bronchoscope contamination. We suggest active surveillance of all bronchoscopy specimen cultures, standardization of connectors of various scopes and automated processors, and systematic education of staff by manufacturers with periodic on-site observation.

Measures against Contamination of Bronchoscopes with Mycrobacteria Linked to an Automatic Endoscope Washer

Measures against Contamination of Bronchoscopes with Mycrobacteria Linked to an Automatic Endoscope Washer

An outbreak of multidrug-resistant Pseudomonas aeruginosa infection associated with contamination of bronchoscopes and an endoscope washer-disinfector

Over a two-month period, two distinct types of Pseudomonas aeruginosa resistant to ceftazidime and azlocillin were isolated from bronchial specimens of ITU patients who had been previously bronchoscoped. The source of the outbreak was probably a faulty contaminated bronchoscope washer-disinfector which had been purchased a year earlier but not properly maintained. This paper describes the outbreak, the identification and elimination of the source, and the steps taken to prevent recurrence. Several automated, closed washer-disinfectors had been bought by the hospital in response to health and safety concerns about glutaraldehyde disinfection toxicity, but the operation and maintenance of these machines had not been supervised. Several other washer-disinfectors were also found to be faulty. The potential hazards of automated endoscope washer-disinfectors and the importance of controlled professional maintenance, servicing and training is discussed.

Nosocomial infections and pseudoinfections from contaminated bronchoscopes: two-year follow up using molecular markers.

During a 6-month period, two genetically distinct clones were isolated from 65% of patients with Pseudomonas aeruginosa isolated from bronchial specimens obtained during or after bronchoscopy. This epidemic was due to contamination of bronchoscopes by washing machines. After reintroduction of manual disinfection of endoscopes, a significant decrease in the incidence of the epidemic clones was observed, but the incidence of nonepidemic P aeruginosa did not change. The distinction between sporadic and epidemic cases was possible only with the use of a molecular typing method (ribotyping).