An outbreak of bronchoscopy-related Mycobacterium tuberculosis infections due to lack of bronchoscope leak testing

Navigating Diagnostic Pitfalls: False Positivity in GeneXpert Mycobacterium Tuberculosis/Rifampicin Assay

Tuberculosis (TB), which is predominantly caused by Mycobacterium tuberculosis (MTB), poses severe diagnostic hurdles, especially with pulmonary tuberculosis (PTB), which spreads by aerosols. Sputum culture, the gold standard for MTB diagnosis, is time-consuming, expensive, and easily contaminated. The GeneXpert MTB/RIF (Xpert) assay, a molecular diagnostic tool, can quickly detect MTB and rifampicin (RIF) resistance. However, the ability to identify both live and non-viable MTB DNA, for example, in patients with a previous history of pulmonary tuberculosis or sampling from a contaminated bronchoscope, can result in false positives, as demonstrated in this case series. We present three cases of PTB diagnosed with Xpert, each with no conventional TB symptoms.

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.

Good Practices on Endoscope Reprocessing in Italy: Findings of a Nationwide Survey

Background: Correct reprocessing and microbiological surveillance on endoscopes are fundamental for preventing the transmission of multi-drug resistant strains and device-related infections. Methods: A questionnaire with three domains was created: (1) centre characteristics; (2) endoscope reprocessing procedures; and (3) application of microbiological surveillance. Nurses working in endoscopic units across Italy were invited to anonymously fill out the questionnaire on the SurveyMonkey platform between November 2021 and February 2022. Results: A total of 82 out of 132 endoscopic centres participated in the survey, with at least one centre from each Italian region. Data found different concerns regarding the current practice of both reprocessing and microbiological surveillance. According to respondents, the training on reprocessing was performed through theoretical training and only in 10% of centres; the microbiological surveillance was regularly performed in 59% of centres; and sampled endoscopes were not excluded for use in 31% of centres performing the surveillance until the outcome was pending, and when positive, 72% maintained them in quarantine until a successive negative result. Conclusions: Reprocessing and microbiological surveillance currently present several criticisms along the endoscopic centres in Italy. Our survey highlights the need for the correct application of the national recommendations in each endoscopic centre to prevent the potential transmission of endoscope-related infections.

Sans Standardization: Effective Endoscope Reprocessing

Bronchoscopy is a commonly performed procedure within thoracic and critical care medicine. Modern bronchoscopes are technologically advanced tools made of fragile electronic components. Their design is catered to allow maximum maneuverability within the semi-rigid tracheobronchial tree. Effective cleaning and reprocessing of these tools can be a challenge. Although highly functional, the design poses several challenges when it comes to reprocessing. It is a very important step, and lapses in the procedure have been tied to nosocomial infections. The process lacks universal standardization; several organizations have developed their own recommendations. Data have shown that key stakeholders are not fully versed in the essentials of endoscope reprocessing. A significant knowledge gap exists between those performing bronchoscopy and those who are stewards of effective endoscope reprocessing. To service as a resource for bronchoscopists, this study summarizes the steps of effective reprocessing, details the important elements within a health-care facility that houses this process, and reviews some of the current data regarding the use of disposable endoscopes.

Multisocieties position paper: Microbiological surveillance on flexible endoscopes

Transmission with endoscopes, particularly duodenoscope, of potential lethal infections prompted different scientific societies to deliver recommendations aimed reducing this risk. Some International societies extended recommendations on microbial surveillance to all the endoscopes and devices used in the reprocessing procedure. Considering the relevance of the topic, 8 Italian scientific societies of physicians, nurses and technical operators prepared a concerted document taking into account Institutional advisories and facilities in Italy. The rules for a correct microbial surveillance on endoscopes were detailed in term of what, how and when to perform the procedure, also suggesting behaviors in case of contamination.

Methods for Endoscope Reprocessing

Over the past 2 decades, in hospital centers worldwide, there have been numerous outbreaks of multidrug-resistant organisms that have since been attributed to endoscopic transmission of the infections between patients, primarily from duodenoscopes. These outbreaks have focused the attention of endoscope manufacturers, professional societies, and regulatory agencies on improving the reprocessing of these devices. The key steps in this process are point-of-use precleaning, leak testing, manual cleaning, high-level disinfection, and finally drying and storage. The promise of these initial efforts suggest that the aim of minimizing and ultimately eliminating events of endoscope-/duodenoscope-associated transmission of infectious organisms between patients can be achieved.

Comparison of a rapid detection fluorescence-based assay targeting tuberculocidal efficacy with EN 14348 and EN 14563

BACKGROUND

A rapid test system using fluorescent Mycobacterium terrae to evaluate the tuberculocidal efficacy of disinfectants has recently been published. Results were obtained in a significantly shorter time than was previously possible.

AIM

To compare the European Standard test system with the fluorescence assay and to validate the rapid test system, including particularly the quantitative suspension test.

METHODS

Quantitative suspension tests and quantitative carrier tests were carried out according to EN 14348 and EN 14563, respectively. Quantitative carrier tests and subsequent green fluorescent protein (GFP)-based determination of germicidal efficacy were carried out as described previously. A peracetic acid-based formulation was used as a test germicide.

FINDINGS

Testing of the germicide in the quantitative suspension test EN 14348 and in the quantitative carrier test EN 14563 revealed tuberculocidal efficacy at a concentration of 1% after 15 min contact time. Accordingly, data obtained from the fluorescence assay demonstrated that a germicide concentration of 1% was effective after 15 min, indicating no live mycobacteria following this treatment. Thus, identical in-use parameters for tuberculocidal efficacy were obtained either by applying the quantitative suspension and quantitative carrier tests EN 14348 and EN 14563 or by using the GFP-based rapid test system.

CONCLUSION

The GFP-based rapid test system compares well with the established European Standard test procedure including both phase 2, step 1 and phase 2, step 2 tests and provides a rapid and sensitive tool for testing germicides for relevant in-use concentrations and contact times.

A systematic review and cost effectiveness analysis of reusable vs. single-use flexible bronchoscopes

The cost effectiveness of reusable vs. single‐use flexible bronchoscopy in the peri‐operative setting has yet to be determined. We therefore aimed to determine this and hypothesised that single‐use flexible bronchoscopes are cost effective compared with reusable flexible bronchoscopes. We conducted a systematic review of the literature, seeking all reports of cross‐contamination or infection following reusable bronchoscope use in any clinical setting. We calculated the incidence of these outcomes and then determined the cost per patient of treating clinical consequences of bronchoscope‐induced infection. We also performed a micro‐costing analysis to quantify the economics of reusable flexible bronchoscopes in the peri‐operative setting from a high‐throughput tertiary centre. This produced an accurate estimate of the cost per use of reusable flexible bronchoscopes. We then performed a cost effectiveness analysis, combining the data obtained from the systematic review and micro‐costing analysis. We included 16 studies, with a reported incidence of cross‐contamination or infection of 2.8%. In the micro‐costing analysis, the total cost per use of a reusable flexible bronchoscope was calculated to be £249 sterling. The cost per use of a single‐use flexible bronchoscope was £220 sterling. The cost effectiveness analysis demonstrated that reusable flexible bronchoscopes have a cost per patient use of £511 sterling due to the costs of treatment of infection. The findings from this study suggest benefits from the use of single‐use flexible bronchoscopes in terms of cost effectiveness, cross‐contamination and resource utilisation.

Guidelines for diagnostic flexible bronchoscopy in adults: Joint Indian Chest Society/National College of chest physicians (I)/Indian association for bronchology recommendations

Flexible bronchoscopy (FB) is commonly performed by respiratory physicians for diagnostic as well as therapeutic purposes. However, bronchoscopy practices vary widely across India and worldwide. The three major respiratory organizations of the country supported a national-level expert group that formulated a comprehensive guideline document for FB based on a detailed appraisal of available evidence. These guidelines are an attempt to provide the bronchoscopist with the most scientifically sound as well as practical approach of bronchoscopy. It involved framing appropriate questions, review and critical appraisal of the relevant literature and reaching a recommendation by the expert groups. The guidelines cover major areas in basic bronchoscopy including (but not limited to), indications for procedure, patient preparation, various sampling procedures, bronchoscopy in the ICU setting, equipment care, and training issues. The target audience is respiratory physicians working in India and well as other parts of the world. It is hoped that this document would serve as a complete reference guide for all pulmonary physicians performing or desiring to learn the technique of flexible bronchoscopy.

The incremental value of bronchoalveolar lavage for the diagnosis of pulmonary tuberculosis in a high-burden urban setting

OBJECTIVES

We prospectively evaluated the use of bronchoalveolar lavage fluid (BALF) specimens to assess their added incremental value to pulmonary tuberculosis (TB) diagnostic strategies used currently in a high-burden urban setting in China.

METHODS

A prospective study was conducted of patients with presumptive pulmonary TB registered at the Fifth Hospital of Suzhou between March 2018 and July 2018. BALF samples from patients with initial Xpert-negative sputum results were tested to diagnose TB.

RESULTS

Of 440 participants, 316 (71.8%) were initially diagnosed with TB from sputum, including 245 (55.7%) definitive TB cases based on a positive culture and/or Xpert result(s) and 71 (16.1%) positive cases based on clinical diagnosis. Of 153 patients with initial positive cultures, a significantly higher proportion were confirmed as TB-positive using Xpert (94.1%) versus smear microscopy (45.8%, P < 0.01). Xpert testing of BALF from 182 Xpert-negative cases exhibited greater detection sensitivity (97.4%) than did smear microscopy (23.4%, P < 0.01). Meanwhile, 74.1% of TB patients initially diagnosed as TB-negative via smear microscopy were identified using Xpert testing of BALF at reduced diagnostic cost/patient (from USD 266.9 to 171.5).

CONCLUSIONS

BALF samples added incremental value to pulmonary TB diagnostic strategies for patients with Xpert-negative sputum. Xpert outperformed smear microscopy for tubercle bacilli detection in both sputum and BALF.

Mycobacterium bovis BCG spinal osteomyelitis in a patient with bladder cancer without a history of BCG instillation

BCG has been used as intravesical immunotherapy for the treatment of bladder carcinoma. However, this treatment is not harmless and may lead to complications, with a reported incidence of systemic BCG infection ranging from 3% to 7%. We report a case of culture-proven Mycobacterium bovis (BCG) vertebral osteomyelitis in a 72-year-old patient with bladder carcinoma who was treated with intravesical mitomycin C but did not receive BCG. Cultures from biopsy recovered isolate resembling Mycobacterium tuberculosis biochemically, but resistant to pyrazinamide (PZA). The patient was originally started on a four-drug antituberculous regimen of isoniazid, rifampin, ethambutol and PZA. After genotypic analysis identified the organism as M. bovis (BCG), the regimen was changed to isoniazid and rifampin for 12 months. The patient responded well to this treatment. This case is unique as the patient received only intravesical mitomycin and did not receive BCG, implying the possibility of transmission from contaminated equipment.

Tuberkulose und andere durch Luft übertragbare Infektionserkrankungen: Krankenhaushygiene zur Vermeidung und Eindämmung

Die Tuberkulose (TB) gehört weltweit zu den am häufigsten auftretenden Infektionskrankheiten und wird fast ausschließlich über die Luft (aerogen) übertragen. Nachdem in Deutschland die Lungentuberkulosefallzahlen über Jahre hinweg stagnierten, ist seit 2013 wieder ein Anstieg der Inzidenzen zu verzeichnen (RKI 2016). Als Ursache hierfür werden die aktuellen demographischen Entwicklungen (Migration und Mobilität) gesehen. Die Kenntnis der epidemiologischen Situation ist von zentraler Bedeutung, um bei Vorliegen der Verdachtsdiagnose Tuberkulose sowie der Einbeziehung einer möglichen Resistenzproblematik frühzeitig adäquate krankenhaushygienische Maßnahmen einzuleiten. Als aerogen übertragbar werden auch die Aspergillose sowie Masern, Windpocken und Herpes zoster eingestuft (CDC 2007). Die Aspergillose ist eine relativ seltene, aber häufig letal verlaufende Pilzinfektion, die überwiegend bei immunsupprimierten Patienten auftritt. Krankenhaushygienische Schutzmaßnahmen können die Risiken einer Exposition und somit das Erkrankungsrisiko minimieren. Die zentralen Maßnahmen zur Kontrolle und Prävention von aerogen übertragbaren Infektionen sind Gegenstand dieses Kapitels.

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

Background

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

Aim

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

Methods

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

Findings

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

Conclusion

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

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.

Hygiene: The Looming Achilles Heel in Endoscopy

BACKGROUND

Since the late 1970s there have been sporadic reports of nosocomial infections linked to endoscopic procedures. Infections by multidrug-resistant organisms (MDRO) have an increasing impact on healthcare systems worldwide. Since 2010 outbreaks involving MDRO have been reported as a result of endoscopic retrograde cholangiopancreatography (ERCP) from the USA, France, Germany and the Netherlands.

METHODS

This article evaluates the recent outbreaks and developments and demonstrates a structural approach to how to prevent future infections. Current national and international guidelines were used as a basis for discussions.

RESULTS

In some cases insufficient cleaning or drying supported the outbreak. In the majority of cases, outbreaks occurred despite the apparently appropriate reprocessing protocols being in use. Microlesions were identified on a number of endoscopes, which supported the growth of bacteria and represented a vehicle for the transmission of infectious material. National official bodies responded with warnings. Manufacturers informed their customers accordingly. Separate, purpose-designed reprocessing rooms and a sufficient number of competent staff provide the structural quality for a safe reprocessing. The process quality includes a thorough cleaning of all endoscope channels and crucial instrument components, followed by an automated and validated reprocessing procedure. Strict adherence to manufacturers' recommendations is essential. The outcome quality should be evaluated by regular audits, validation of reprocessing procedures and microbiological surveillance. If outbreaks occur, a close co-operation with official bodies and manufacturers is essential.

CONCLUSION

Health care professionals and manufacturers should be aware of their responsibility to ensure patient safety. A structural approach is key in prevention of endoscopy-associated infections.

Infectious diseases linked to cross-contamination of flexible endoscopes

Flexible endoscopes are widely used to examine, diagnose, and treat medical disorders. While the risk of endoscopy-related transmission of infection is estimated to be very low, more health care-associated infections are related to contaminated endoscopes than to any other medical device. Flexible endoscopes can get highly contaminated with microorganisms, secretions and blood during use. The narrow lumens and multiple internal channels make the cleaning of flexible endoscopes a complex and difficult task. Despite the availability of international, national and local endoscope reprocessing guidelines, contamination and transmission of microorganisms continue to occur. These transmissions are mostly related to the use of defective equipment, endoscope reprocessing failures, and noncompliance with recommended guidelines. This article presents an overview of publications about case reports and outbreaks related to contamination of flexible endoscopes.

Risk Factors forBurkholderia cepaciaComplex Bacteremia Among Intensive Care Unit Patients Without Cystic Fibrosis: A Case-Control Study

Background.

TheBurkholderia cepaciacomplex is associated with colonization or disease in patients with cystic fibrosis (CF). For patients without CF, this complex is poorly understood apart from its presence in occasional point source outbreaks.

Objective.

To investigate risk factors forB. cepaciabacteremia in hospitalized, intensive care unit patients without CF.

Methods.

We identified patients with 1 or more blood cultures positive forB. cepaciabetween May 1, 1996, and March 31, 2002, excluding those with CF. Control patients were matched to case patients by ward, duration of hospitalization, and onset date of bacteremia. Matched analyses were used to identify risk factors forB. cepaciabacteremia.

Results.

We enrolled 40 patients withB. cepaciabacteremia into the study. No environmental or other point source forB. cepaciacomplex was identified, although horizontal spread was suspected. Implementation of contact precautions was effective in decreasing the incidence ofB. cepaciabacteremia. We selected 119 matched controls. Age, sex, and race were similar between cases and controls. In multivariable analysis, renal failure that required dialysis, recent abdominal surgery, 2 or more bronchoscopic procedures before detection ofB. cepaciabacteremia, tracheostomy, and presence of a central line before detection ofB. cepaciabacteremia were independently associated with development ofB. cepaciabacteremia, whereas presence of a percutaneous feeding tube was associated with a lower risk of disease.

Conclusions.

B. cepaciacomplex is an important emerging group of nosocomial pathogens in patients with and patients without CF. Nosocomial spread is likely facilitated by cross-transmission, frequent pulmonary procedures, and central venous access. Infection control measures appear useful for limiting the spread of virulent, transmissible clones ofB. cepaciacomplex.

Transmission of infection by flexible gastrointestinal endoscopy and bronchoscopy

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

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

BACKGROUND

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

AIM

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

METHODS

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

FINDINGS

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

CONCLUSION

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

Medical errors, infection-control breaches and the use of adulterated and misbranded medical devices

Several well-publicized cases of improper cleaning, disinfection or sterilization of contaminated reusable medical equipment that posed an increased risk of patient-to-patient disease transmission were reported within the past few years, resulting in the notification of approximately 20 000 patients. These medical errors, the specific infection-control standards they breached, and assessments of the risk of infection associated with each are discussed. Other topics discussed include the Food and Drug Administration’s (FDA) regulation of medical devices and infection-control products; the use of adulterated, misbranded, and investigational devices; consent decrees and associated Certificates of Medical Necessity; and informed patient consent. Focus is placed on liquid chemical sterilization, its history, and the FDA’s recent censure and discontinuation of a medical device labeled with this claim, namely, the STERIS System 1 processor. Recommendations are provided for healthcare facilities, regulatory agencies, manufacturers of reusable medical devices, and professional healthcare organizations and administrations to improve public health and prevent healthcare-associated infections.

Bronchoscopy in suspected pulmonary TB with negative induced-sputum smear and MTD(®) Gen-probe testing

INTRODUCTION

In our institution, patients with suspected pulmonary TB undergo multiple induced-sputum sampling for microscopy, culture and nucleic acid amplification (NAA) with the MTD(®) Gen-probe assay. Those with negative induced-sputum results still suspected with TB are then referred for bronchoscopy. We sought to determine the diagnostic yield of bronchoscopy in these patients with negative initial induced-sputum results both via smear and NAA testing.

METHODS

We identified 30 consecutive cases of suspected pulmonary TB between 2001 and 2007, who had undergone a diagnostic bronchoscopy after negative results on induced-sputum smears and the MTD(®) Gen-probe on at least 2 samples.

RESULTS

The cohort (M = 20 & F = 10) had a median age of 37 (range 16-85 yrs); were predominantly foreign born (27/30); HIV-negative (29/30) individuals with strongly positive TST's (mean 18 + 5 mm). Induced-sputum cultures were negative for M-TB in all patients after a full 60-day incubation period. BAL was culture positive for M-TB in 3/30 cases (10%) with 2 strains being pan-sensitive and the third being INH resistant. BAL microscopy with acid-fast smear (n = 30) and BAL Gen-probe (n = 23) were negative in all cases. A third of the patients (9/27, 33%) with negative bronchoscopy results were treated for culture negative TB. Treatment for latent TB was initiated in 5/27 (18%) individuals whereas 13/27 (48%) received no further treatment.

CONCLUSION

Bronchoscopy provided diagnostic confirmation of pulmonary TB in 10% of subjects at least 2 negative induced-sputum samples by smear microscopy and NAA testing.

[Diagnostic flexible bronchoscopy. Recommendations of the Endoscopy Working Group of the French Society of Pulmonary Medicine]

These guidelines on flexible bronchoscopy depict important clues to be known and taken into account while practicing flexible bronchoscopy, in adult, except in emergency situations. This is a practical clarification. Safety conditions, complications, anesthesia, infectious risks, cleaning and disinfection are detailed from a review of the literature. Intensive care practice of bronchoscopy requires more attention due to higher risks patients and is discussed extensively. Standards and performances of the various sampling techniques complete this work. Indications for bronchoscopy, therapeutic and paediatric bronchoscopy are not covered in these guidelines.

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

OBJECTIVES

The objective of this study was to analyze the characteristics and costs of exogenous endoscopy-related infections, pseudo-infections, and toxic reactions in the US.

METHODS

A systematic review of the scientific literature published between 1966 and 2005 was conducted in Medline. Data collection was based on a prospective protocol developed by the authors.

RESULTS

The literature review included 70 outbreaks described in 64 scientific articles. Bronchoscopy accounted for half of all reported outbreaks. Inadequate decontamination practices were the leading cause of contamination; equipment malfunction became the second leading cause of contamination during the period 1990-2004. More than 91% of the infections identified could be prevented by health care providers if quality control systems are improved and implemented. The available economic information concerning exogenous endoscope related events is very limited. A model for the analysis of the economic burden of exogenous endoscopy-related events is proposed.

CONCLUSIONS

Proper decontamination practices, the use of protective sheaths, and the improvement of surveillance systems could reduce the clinical and economic burdens associated with exogenous endoscopy-related events.

[Prevention of tuberculosis in care settings]

INTRODUCTION

The hospital is a favourable setting for the transmission of tubercle bacilli. The presence of susceptible subjects, often immunocompromised, increases the dangers. This risk extends to the patients' visitors and to the staff. It is therefore the responsibility of the hospital to establish preventative measures capable of reducing the risk of transmission or to reduce the effects by appropriate management of exposed subjects.

BACKGROUND

The modes and vectors of transmission are well established. The standardised prevention of transmission is achieved by isolation, the indications and duration of which are based on incomplete information. The surveillance of the carers by the doctor in charge, is based on precise recommendations depending on the risk of exposure.

VIEWPOINT

The objectives are a reduction diagnostic delay, a better determination of infectivity and its duration during treatment, and a more complete census of cases of hospital acquired tuberculosis.

CONCLUSIONS

The management of tuberculosis in hospital requires co-ordination of all involved including those outside the institution and a deliberate policy in the institution itself.

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.

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.

Dear Los Angeles Times: the risk of disease transmission during gastrointestinal endoscopy

This is the second in a series of articles that review media reports investigating the risk of disease transmission associated with gastrointestinal flexible endoscopy. The first article in this series, "

COMMENTARY

Do Scopes Spread Sickness?'' was published in this journal in 1999 (Gastroenterology Nursing, 22(4), 179-180).

Nosocomial Transmission of Congenital Tuberculosis in a Neonatal Intensive Care Unit

Congenital tuberculosis is uncommon, and nosocomial transmission from a congenitally infected infant to another infant has not been reported in the English literature. We report an investigation of 2 infants with tuberculosis who were cared for in the same neonatal intensive care unit. Isolates from both infants were genetically indistinguishable. Transmission between the 2 infants was likely due to contaminated respiratory equipment.

Utility of fast mycobacterial interspersed repetitive unit-variable number tandem repeat genotyping in clinical mycobacteriological analysis

BACKGROUND

Analysis of variable numbers of tandem repeats (VNTR) of genetic elements called mycobacterial interspersed repetitive units (MIRUs) is a recently described, polymerase chain reaction (PCR)-based method used to genotype Mycobacterium tuberculosis. It is much faster, requires a smaller amount of DNA, and has approximately the same discriminatory power as the standard IS6110 restriction fragment-length polymorphism (RFLP) method. We report the adaptation and optimization of MIRU-VNTR genotyping on a capillary electrophoresis system. We describe its application to 3 typical clinical situations encountered in our laboratory (Institut Pasteur de Bruxelles, Laboratoire Tuberculose et Mycobacteries; Brussels, Belgium).

METHODS

MIRU-VNTR genotyping was performed on heat-inactivated M. tuberculosis cultures obtained from clinical specimens on Lowenstein solid medium or in mycobacteria growth indicator liquid tubes (Becton Dickinson). After amplification of 12 genomic loci using 4 different multiplex PCRs, DNA fragments were separated by capillary electrophoresis using the ABI Prism 3100-Avant Genetic Analyzer (Applied Biosystems). Sizing of the PCR fragments and assignment of the various MIRU-VNTR alleles were done using the GeneScan and customized Genotyper software packages (PE Applied Biosystem).

RESULTS

Clustering on the basis of IS6110 fingerprinting of isolates from 3 different patients attending the same hospital was confirmed by MIRU-VNTR typing. This concordance between 2 independent, highly discriminatory techniques was decisive in triggering an epidemiological inquiry that led to identification of a bronchoscopy-related tuberculosis nosocomial infection. A mixed tuberculosis infection in a patient whose infection was initially suspected as a result of the IS6110 RFLP method was clearly identified by MIRU-VNTR typing. Finally, automated MIRU-VNTR analysis permitted the identification of laboratory contamination in 6 liquid cultures of M. tuberculosis within several hours.

CONCLUSION

These examples illustrate the utility of this genotyping technique for quick and accurate resolution of problems commonly encountered in clinical mycobacteriology.

Infection control and its application to the administration of intravenous medications during gastrointestinal endoscopy

Several infection control practices and procedures crucial to the prevention of disease transmission in the health care setting are reviewed and discussed. Emphasis is placed on the importance of infection control to gastrointestinal endoscopy. Recommendations that minimize the risk of nosocomial infection during the preparation, handling, and administration of intravenous medications, particularly propofol, are provided. These recommendations include the labeling of predrawn syringes; use of sterile single-use syringes, needles, and administration sets for each patient; and, whenever feasible, administration of intravenous medications promptly after opening their prefilled syringes or after opening their ampoules or vials and filling the sterile syringes.

Bronchoscopy with the Vision Sciences BF100 Disposable-Sheath Device: French Experience after 328 Procedures

BACKGROUND

In spite of adhesion to recommended disinfection procedures, the transmission of infections by bronchoscopes is a permanent problem.

OBJECTIVE

The new device may prevent nosocomial infections because it consists of two parts: a specific bronchoscope Vision Sciences BF100 and a single-use protective sheath for each procedure. The aim of this paper is to report our practice and the difficulties encountered when using this system.

METHODS

We report our experience from 1997 to 2002 after 328 elective and emergency endoscopic procedures with the BF100 device. In a retrospective study, we describe the population and the incidents during procedure. We discuss the impact of the use of BF100 on the cost of bronchoscopies.

RESULTS

The major constraint is the care required in assembling the optical device and disposable sheath. The intrinsic qualities of the optics are confirmed; any sample may be taken although image quality and suction capacity are inferior to videoscopes. Maneuverability is inferior to videoscopes, but improves with a short experience. In addition, this device is expensive.

CONCLUSIONS

The technical performances of the BF100 device are inferior to those of videoscopes but the concept of sterile single-use sheaths is able to prevent the nosocomial infections related to bronchoscopes. Because of the cost, examination with the BF100 should be reserved to patients with proved or suspected infection (multiresistant bacteria, tuberculosis, hepatitis C and B virus, HIV, prions) and immunosuppression (hematologic diseases).

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.

Nosocomial pneumonia: emerging concepts in diagnosis, management, and prophylaxis

Nosocomial pneumonia is a dynamic disease with multiple etiologic agents and a changing natural history. The highest attack rates and mortality occur in patients with ventilator-associated pneumonia. Diagnosis of nosocomial pneumonia is often made by clinical criteria that are sensitive but lack specificity. The use of quantitative endotracheal aspirates or bronchoscopy with bronchoalveolar lavage and protected specimen brush clearly improve diagnostic specificity and outcome in patients who are mechanically ventilated. The rapid spread of multidrug-resistant, spp, and has made initial empiric therapy more difficult. Management principles include the use of techniques for more accurate diagnosis and early antimicrobial therapy with appropriate agents along with careful analysis of culture results, clinical response, and potential complications of pneumonia and therapy. Strategies for prophylaxis are of critical importance for risk reduction, improvement in patient outcome, and reduction of hospital costs.