British Thoracic Society guidelines on diagnostic flexible bronchoscopy

The selected genetic polymorphisms of metalloproteinases MMP2, 7, 9 and MMP inhibitor TIMP2 in sarcoidosis

BACKGROUND

Increased activity of metalloproteinases may play a role in the initiation and propagation of inflammation in sarcoidosis, and may also be one of the factors responsible for the development of lung fibrosis. The aim of this study was to verify whether polymorphisms of MMP2 C-735T, MMP7 A-181G, MMP9 T-1702A and tissue inhibitor of metalloproteinase (TIMP)2 G-418C predispose to sarcoidosis.

MATERIAL/METHODS

The study included 139 patients with sarcoidosis and 100 healthy subjects. MMPs and TIMP2 mRNA were measured in peripheral blood lysate using real-time RT-PCR. DNA for genetic polymorphism was extracted from peripheral blood by GTC method. Protein concentrations in peripheral blood lysates were measured by ELISA, and MMP2 and 9 activities in BAL fluid were estimated by gel zymography.

RESULTS

TT genotype in MMP9 T-1702A was more frequent in sarcoidosis (p<0.0001, OR = 13.71, 95% CI 7.02-26.80) and resulted in higher expression of MMP9 mRNA (p<0.0001). No differences were found between TT and AT/AA patients in terms of radiological stage, lung function test parameters, activity markers and the presence/absence of Löfgren syndrome. There were no differences in the distribution of MMP2, MMP7 and TIMP2 polymorphisms. Messenger RNAs, as well as protein concentrations of MMP2, 7, 9, and TIMP2 were elevated in patients with sarcoidosis (p<0.0001 for each).

CONCLUSIONS

The TT homozygotes of MMP9 T-1702A genotype may be predisposed to sarcoidosis. Elevated MMP2, 7, 9, and TIMP2 mRNAs suggest their inducibility.

Contribution of cell blocks obtained through endobronchial ultrasound-guided transbronchial needle aspiration to the diagnosis of lung cancer

Background

Conventional smears of samples obtained by endobronchial ultrasound with real-time transbronchial needle aspiration (EBUS-TBNA) have proven useful in lung cancer staging, but the value of additional information from cell-block processing of EBUS-TBNA samples has only been marginally investigated. This study focussed on the contribution of cell block analysis to the diagnostic yield in lung cancer.

Methods

Patients referred for lung cancer diagnosis and/or staging by means of EBUS-TBNA were enrolled, the adequacy of the obtained samples for preparing cell blocks was assessed, and the additional pathologic or genetic information provided from cell block analysis was examined.

Results

In 270 lung cancer patients referred for EBUS-TBNA (mean age, 63.3 SD 10.4 years) 697 aspirations were performed. Cell blocks could be obtained from 334 aspirates (47.9%) and contained diagnostic material in 262 (37.6%) aspirates, providing information that was additional to conventional smears in 50 of the 189 samples with smears that were non-diagnostic, corresponding 21 of these blocks to malignant nodes, and allowing lung cancer subtyping of 4 samples. Overall, cell blocks improved the pathologic diagnosis attained with conventional smears in 54 of the 697 samples obtained with EBUS-TBNA (7.7%). Cell blocks obtained during EBUS-TBNA also made epithelial growth factor receptor mutation analysis possible in 39 of the 64 patients with TBNA samples showing metastatic adenocarcinoma (60.1%). Overall, cell blocks provided clinically significant information for 83 of the 270 patients participating in the study (30.7%).

Conclusions

Cell-block preparation from EBUS-TBNA samples is a simple way to provide additional information in lung cancer diagnosis. Analysis of cell blocks increases the diagnostic yield of the procedure by nearly seven per cent and allows for genetic analysis in a sixty per cent of the patients with metastatic adenocarcinoma.

Feasibility of bispectral index-guided propofol infusion for flexible bronchoscopy sedation: a randomized controlled trial

OBJECTIVES

There are safety issues associated with propofol use for flexible bronchoscopy (FB). The bispectral index (BIS) correlates well with the level of consciousness. The aim of this study was to show that BIS-guided propofol infusion is safe and may provide better sedation, benefiting the patients and bronchoscopists.

METHODS

After administering alfentanil bolus, 500 patients were randomized to either propofol infusion titrated to a BIS level of 65-75 (study group) or incremental midazolam bolus based on clinical judgment to achieve moderate sedation. The primary endpoint was safety, while the secondary endpoints were recovery time, patient tolerance, and cooperation.

RESULTS

The proportion of patients with hypoxemia or hypotensive events were not different in the 2 groups (study vs. control groups: 39.9% vs. 35.7%, p = 0.340; 7.4% vs. 4.4%, p = 0.159, respectively). The mean lowest blood pressure was lower in the study group. Logistic regression revealed male gender, higher American Society of Anesthesiologists physical status, and electrocautery were associated with hypoxemia, whereas lower propofol dose for induction was associated with hypotension in the study group. The study group had better global tolerance (p<0.001), less procedural interference by movement or cough (13.6% vs. 36.1%, p<0.001; 30.0% vs. 44.2%, p = 0.001, respectively), and shorter time to orientation and ambulation (11.7±10.2 min vs. 29.7±26.8 min, p<0.001; 30.0±18.2 min vs. 55.7±40.6 min, p<0.001, respectively) compared to the control group.

CONCLUSIONS

BIS-guided propofol infusion combined with alfentanil for FB sedation provides excellent patient tolerance, with fast recovery and less procedure interference.

TRIAL REGISTRATION

ClinicalTrials. gov NCT00789815.

An alternative therapy for idiopathic pulmonary fibrosis by doxycycline through matrix metalloproteinase inhibition

BACKGROUND

Idiopatiic pulmonary fibrosis (IPF) is a disease of dysregulated fibrogenesis with abnormal matrix metalloproteinase (MMPs) activity, angiogenesis, and profibrotic milieu wherein MMPs inhibition appears to be target-based therapy. We evaluated the role of doxycycline as a nonspecific inhibitor of MMPs in IPF patients.

MATERIALS AND METHODS

Patients of IPF diagnosed on the basis of ATS-ERS consensus criteria were put on oral doxycycline in an open prospective trial. They were followed up for long term with spirometry, 6 min walk test (6MWT), St. Georges respiratory questionnaire (SGRQ), forced vital capacity (FVC), and repeat bronchoscopy while on doxycycline monotherapy for over 24 weeks. Both the initial and follow-up broncho alveolar lavage fluids (BALF) from IPF patients (n = 6) and control subjects (n = 6) were looked for MMP-9, -3, tissue inhibitor of metalloproteinase (TIMP)-1 and vascular endothelial growth factor (VEGF) expression. Additionally, doxycycline's action on MMP activities in vitro was tested in BALF of IPF patients.

RESULTS

Doxycycline intervention showed significant improvement in IPF patients in terms of change in 6MWT, SGRQ, FVC, and quality of life. The level of MMP-9, -3, TIMP-1 and VEGF in the BALF were found significantly higher in the IPF patients compared to the controls while doxycycline therapy reduced those parameters nearer to control value. Doxycycline also showed a significant dose-dependent reduction in the in vitro MMPs activities in BALF.

CONCLUSION

Doxycycline shows significant prospect in the treatment of IPF through its anti MMPs activities. This is the first report on a case series of long-term doxycycline monotherapy in IPF patients.

Posture influences patient cough rate, sedative requirement and comfort during bronchoscopy: An observational cohort study

Objectives

To investigate differences between semi-recumbent and supine postures in terms of cough rate, oxygen desaturation, sedative use, and patient comfort during the initial phase of bronchoscopy.

Methods

Consecutive bronchoscopy patients (n = 69) participated in this observational cohort study. Posture was determined by the bronchoscopist's usual practice. Patient demographics, spirometry, pulse, and SpO₂ were recorded. The initial phase was defined as the time from bronchoscopy insertion to visualisation of both distal main bronchi. Cough rate, peak pulse, nadir SpO₂, oxygen supplementation, and sedative use during the initial phase were recorded. A post-procedure questionnaire was administered to the patient and the attending nurse.

Results

36 patients had bronchoscopy in the semi-recumbent posture, 33 in the supine posture. 3 of 5 bronchoscopists performed in both postures. There were no differences in baseline parameters between the groups. The semi-recumbent posture resulted in significantly less cough (mean (SD) 3.6 (2.3) vs. 6.1 (4.5) coughs/min, p = 0.007) and less fentanyl use (70 (29) vs. 88 (28) mcg, p = 0.011) in the initial phase. There were no significant differences in the nadir SpO₂, fall in SpO₂, oxygen supplementation, or increase in pulse rate between the groups. On 100 mm visual analogue scale, nurse perception of patient discomfort was lower in the semi-recumbent position (23 (21) vs. 39 (28) mm, p = 0.01), and there was a trend towards less patient perceived cough in the semi-recumbent group (28 (25) vs. 40 (28) mm, p = 0.06).

Conclusions

Bronchoscopy performed in the semi-recumbent posture results in less cough and sedative requirement, and may improve patient comfort.

Establishing pass/fail criteria for bronchoscopy performance

BACKGROUND

Several tools have been created to assess competence in bronchoscopy. However, educational guidelines still use an arbitrary number of performed procedures to decide when basic competency is acquired.

OBJECTIVES

The purpose of this study was to define pass/fail scores for two bronchoscopy assessment tools, and investigate how these scores relate to physicians' experience regarding the number of bronchoscopy procedures performed.

METHODS

We studied two assessment tools and used two standard setting methods to create cut scores: the contrasting-groups method and the extended Angoff method. In the first we compared bronchoscopy performance scores of 14 novices with the scores of 14 experienced consultants to find the score that best discriminated between the two groups. In the second we asked an expert group of 7 experienced bronchoscopists to judge how a borderline trainee would perform on each item of the test.

RESULTS

Using the contrasting-groups method we found a standard that would fail all novices and pass all consultants. A clear pass related to prior experience of 75 procedures. The consequences of using the extended Angoff method were also acceptable: all trainees who had performed less than 50 bronchoscopies failed the test and all consultants passed. A clear pass related to 80 procedures.

CONCLUSIONS

Our proposed pass/fail scores for these two methods seem appropriate in terms of consequences. Prior experience with the performance of 75 and 80 bronchoscopies, respectively, seemed to ensure basic competency. In the future objective assessment tools could become an important aid in the certification of physicians performing bronchoscopies.

Fiber optic bronchoscopy in patients with acute hypoxemic respiratory failure requiring noninvasive ventilation--a feasibility study

Introduction

Noninvasive ventilation (NIV) is a standard procedure in selected patients with acute respiratory failure. Previous studies have used noninvasive ventilation to ensure adequate gas exchange during fiberoptic bronchoscopy in spontaneously breathing hypoxemic patients, thus avoiding endotracheal intubation. However, it is unknown whether bronchoscopy can be performed safely in patients with acute hypoxemic respiratory failure already in need of NIV prior to the decision for bronchoscopy.

Methods

We prospectively investigated 40 consecutive, critically ill, adult patients with acute hypoxemic respiratory failure (14 women, 26 men, age 61 ± 15 years, partial pressure for oxygen/fraction of inspired oxygen (PaO₂/FiO₂) < 300 under noninvasive ventilation, Simplified Acute Physiology scores (SAPS II) 47 ± 9.9 points). All patients required noninvasive ventilation prior to the decision to perform bronchoscopy (median 10.5 h; range 2.2 to 114). Blood gases, heart rate, blood pressure and ventilation were monitored before, during and up to 120 minutes after bronchoscopy.

Results

Bronchoscopy could be completed in all patients without subsequent complications. Oxygen saturation fell to < 90% in two patients (5%), and the lowest value during the procedure was 84%. The mean PaO₂/FiO₂ ratio improved from 176 ± 54 at baseline to 240 ± 130 (P < 0.001) at the end of bronchoscopy and 210 ± 79 after 120 minutes. The transient mean partial pressure of carbon dioxide in the arterial blood (PaCO₂) increase was 9.4 ± 8.1 mm Hg. Four patients (10%) required endotracheal intubation during the first eight hours after the procedure. Bronchoalveolar lavage yielded diagnostic information in 26 of 38 (68%) patients.

Conclusions

In critically ill patients with acute hypoxemic respiratory failure requiring noninvasive ventilation, bronchoscopy can be performed with an acceptable risk. Since these patients per se have a high likelihood of subsequent endotracheal intubation due to failure of NIV, bronchoscopy should only be performed by experienced clinicians.

Local Anaesthesia for Fiberoptic Intubation : A Comparison of Three Techniques

BACKGROUND

The successful conduct of fiberoptic aided intubation is dependent upon effective local anaesthesia. The aim of the study was to compare three different methods of anaesthetizing the airway.

METHODS

60 adult patients (American Society of Anaesthesiologists status I-III and Mallampati class III & IV), scheduled for elective surgery, received sedation followed by spraying of the nares and posterior pharyngeal wall with 4% lignocaine. Thereafter the patients received 4 ml of 4% lignocaine either by transtracheal injection (n=20, group A), via intubating fiberscope (Pentax F1-10P2) using 'spray as you go' technique (n=20, group B) or by nebulizer (Devilbiss 5610W) 20 min before intubation, (n=20, group C). Patients were asked to score the procedure using visual analog scale (VAS) and severity scores. Episodes of coughing, choking, stridor, extra / total local anaesthetic used and intubation times were recorded. Patients were monitored continuously for vital parameters.

RESULTS

Group B patients showed better VAS scores with shorter intubation times and had a lower incidence of coughing and choking. The endoscopists' VAS scores also showed a preference for group B.

CONCLUSION

In conclusion the 'spray as you go' technique was safe, provided effective local anaesthesia and was preferred by both patients and endoscopists.

Experimental rhinovirus infection as a human model of chronic obstructive pulmonary disease exacerbation

RATIONALE

Respiratory virus infections are associated with chronic obstructive pulmonary disease (COPD) exacerbations, but a causative relationship has not been proven. Studies of naturally occurring exacerbations are difficult and the mechanisms linking virus infection to exacerbations are poorly understood. We hypothesized that experimental rhinovirus infection in subjects with COPD would reproduce the features of naturally occurring COPD exacerbations and is a valid model of COPD exacerbations.

OBJECTIVES

To evaluate experimental rhinovirus infection as a model of COPD exacerbation and to investigate the mechanisms of virus-induced exacerbations.

METHODS

We used experimental rhinovirus infection in 13 subjects with COPD and 13 nonobstructed control subjects to investigate clinical, physiologic, pathologic, and antiviral responses and relationships between virus load and these outcomes.

MEASUREMENTS AND MAIN RESULTS

Clinical data; inflammatory mediators in blood, sputum, and bronchoalveolar lavage; and viral load in nasal lavage, sputum, and bronchoalveolar lavage were measured at baseline and after infection with rhinovirus 16. After rhinovirus infection subjects with COPD developed lower respiratory symptoms, airflow obstruction, and systemic and airway inflammation that were greater and more prolonged compared with the control group. Neutrophil markers in sputum related to clinical outcomes and virus load correlated with inflammatory markers. Virus load was higher and IFN production by bronchoalveolar lavage cells was impaired in the subjects with COPD.

CONCLUSIONS

We have developed a new model of COPD exacerbation that strongly supports a causal relationship between rhinovirus infection and COPD exacerbations. Impaired IFN production and neutrophilic inflammation may be important mechanisms in virus-induced COPD exacerbations.

Respiratory syncytial virus as a cause of pulmonary hemorrhage in a low birth weight infant: strategies for protection and prevention: a case report

INTRODUCTION

Respiratory syncytial virus is a common neonatal pathogen. Here we present a case of a premature, low birth weight infant who contracted respiratory syncytial virus and developed a severe pulmonary hemorrhage.

CASE PRESENTATION

A 12-day-old Asian male, former 30 week premature infant with a birth weight of 1025 grams presented with nasal secretions, episodes of desaturations and increased work of breathing. The infant developed a pulmonary hemorrhage. Secretions during tracheal lavage were positive for respiratory syncytial virus on rapid fluorescence assay. After supportive care, the patient improved. Isolation, cohorting techniques and reinforcement of strict hand-washing guidelines prevented and outbreak to other infants.

CONCLUSION

This original case report presents an uncommon presentation of respiratory syncytial virus infection, a common pediatric pathogen. Neonatologists should consider evaluating patients with pulmonary hemorrhage for respiratory syncytial virus if preceding symptoms are consistent with that infectious illness.

Fospropofol Disodium for Sedation in Elderly Patients Undergoing Flexible Bronchoscopy

BACKGROUND: Fospropofol disodium is a water-soluble prodrug of propofol. A subset analysis was undertaken of elderly patients (≥65 y) undergoing flexible bronchoscopy, who were part of a larger multicenter, randomized, double-blind study. METHODS: Patients received fentanyl citrate (50 mcg) followed by fospropofol at initial (4.88mg/kg) and supplemental (1.63mg/kg) doses. The primary end point was sedation success (3 consecutive Modified Observer's Assessment of Alertness/Sedation scores of ≤4 and procedure completion without alternative sedative or assisted ventilation). Treatment success, time to fully alert, patient and physician satisfaction, and safety/tolerability were also evaluated. RESULTS: In the elderly patients subset (n=61), sedation success was 92%, the mean time to fully alert was 8.0±10.9 min, and memory retention was 72% during recovery, and these were comparable with the younger patients subgroup (age, <65 y). Sedation-related adverse events occurred in 23% of the elderly and 18% of the younger patients (age, <65 y) group. Hypoxemia occurred in 26% of the elderly and 18% of the younger patients group, but no escalation of care was required. CONCLUSIONS: Fospropofol provided safe and effective sedation, rapid time to fully alert, and high satisfaction in this elderly subset undergoing flexible bronchoscopy, which was comparable with outcomes in younger patients.

Influence of additional post-bronchoscopy visit on patient satisfaction after flexible bronchoscopy

BACKGROUND/AIMS

Many patients undergoing a flexible bronchoscopy (FB) experience anxiety and discomfort during the procedure. We assessed whether an additional patient visit after a FB would improve patient satisfaction.

METHODS

The study patients were randomly assigned to a control and post-visit groups. The physicians who were scheduled to perform the FB visited the study patients. The control group had one visit before the FB and the post-visit group had a before and after FB visit. The post-visit group received additional information and support during the second visit. Twenty-four hours after the FB, the participants completed questionnaires about discomfort and satisfaction with the procedure.

RESULTS

The control and post-visit groups included 151 and 153 patients, respectively. The post-visit group reported having more information after the FB than the control group. The additional post-bronchoscopy visit improved the general patient tolerability of the procedure. The willingness to return for another FB was not affected by the post-bronchoscopy patient visit.

CONCLUSIONS

The post-bronchoscopy visit improved patient satisfaction and general tolerability to the procedure. Subjective patient tolerability with the FB may be improved through a post-bronchoscopy visit by providing more information and emotional support to patients.

Expression of the T helper 17-associated cytokines IL-17A and IL-17F in asthma and COPD

Background:

Asthma and COPD are characterized by airway dysfunction and inflammation. Neutrophilic airway inflammation is a common feature of COPD and is recognized in asthma, particularly in severe disease. The T helper (Th) 17 cytokines IL-17A and IL-17F have been implicated in the development of neutrophilic airway inflammation, but their expression in asthma and COPD is uncertain.

Methods:

We assessed IL-17A and IL-17F expression in the bronchial submucosa from 30 subjects with asthma, 10 ex-smokers with mild to moderate COPD, and 27 nonsmoking and 14 smoking control subjects. Sputum IL-17 concentration was measured in 165 subjects with asthma and 27 with COPD.

Results:

The median (interquartile range) IL-17A cells/mm² submucosa was increased in mild to moderate asthma (2.1 [2.4]) compared with healthy control subjects (0.4 [2.8]) but not in severe asthma (P = .04). In COPD, IL-17A⁺ cells/mm² submucosa were increased (0.5 [3.7]) compared with nonsmoking control subjects (0 [0]) but not compared with smoking control subjects (P = .046). IL-17F⁺ cells/mm² submucosa were increased in severe asthma (2.7 [3.6]) and mild to moderate asthma (1.6 [1.0]) compared with healthy controls subjects (0.7 [1.4]) (P = .001) but was not increased in subjects with COPD. IL-17A and IL-17F were not associated with increased neutrophilic inflammation, but IL-17F was correlated with the submucosal eosinophil count (rs = 0.5, P = .005). The sputum IL-17 concentration in COPD was increased compared with asthma (2 [0-7] pg/mL vs 0 [0-2] pg/mL, P < .0001) and was correlated with post-bronchodilator FEV₁% predicted (r = −0.5, P = .008) and FEV₁/FVC (r = −0.4, P = .04).

Conclusions:

Our findings support a potential role for the Th17 cytokines IL-17A and IL-17F in asthma and COPD, but do not demonstrate a relationship with neutrophilic inflammation.

Exhaled 8-isoprostane in sarcoidosis: relation to superoxide anion production by bronchoalveolar lavage cells

Objective

This study was designed to examine the mutual relationship between 8-isoprostane in exhaled breath condensate (EBC) and superoxide anion generation by bronchoalveolar lavage fluid (BALF) cells in patients with sarcoidosis.

Design

About 29 patients with sarcoidosis, 34 healthy never smokers (control group for EBC) and 15 healthy never smokers (control group for BAL) were examined. EBC was collected directly before bronchoscopy. 8-Isoprostane was measured by ELISA, and superoxide anion by colorimetry.

Results

Exhaled breath condensate 8-isoprostane is increased in sarcoidosis (median, 25–75 percentile): 2.50; 2.50–3.90 versus 6.20; 2.50–16.95 pg/ml, p ≤ 0.05). Spontaneous superoxide anion release from BALF cells was significantly elevated only in patients with a high percentage of lymphocytes in BALF (6.42 ± 1.24 vs. 23.52 ± 4.30 nmol/10⁶ cells, p ≤ 0.01). There were no correlations between 8-isoprostane and spontaneous or stimulated superoxide anion release.

Conclusions

We confirmed higher concentrations of EBC 8-isoprostane in sarcoidosis and higher spontaneous release of superoxide anion from BALF cells in patients with sarcoidosis. The increase of EBC 8-isoprostane is not directly related to superoxide anion released from BALF cells.

Exhaled 8-isoprostane as a prognostic marker in sarcoidosis. A short term follow-up

Background

8-Isoprostane (8-IP) is a marker of lipid peroxidation. Elevated concentrations have been reported in BAL fluid and exhaled breath condensate (EBC) in sarcoidosis (S). To validate the prognostic value of this marker we tested whether: 1. high initial EBC 8-IP predispose to more severe disease; 2. low initial concentrations increase a chance of early remission; 3. remissions are connected with the decrease of EBC 8-IP.

Methods

40 patients (S) have been examined initially (V1) and after 8.5 ± 0.5 months (V2). EBC 8-IP concentrations were measured by ELISA. Chest X-ray, lung function test, serum ACE and Ca²⁺ concentrations, 24 hrs Ca²⁺loss, abdominal ultrasonography, symptoms evaluation were performed.

Results

We confirmed higher concentrations of 8-IP in EBC of patients with sarcoidosis (p = 0.001). Relative risk (RR) of persistence of disease at V2 when initial 8-IP was above 20 pg/mL was 1.04, and the frequency distributions estimated by χ² test were not significantly different. A chance (RR) of early complete remission when V1 8-IP was below DL, was 3.33 (p = 0.04 by χ² test). A significant decrease of 8-IP at V2 was observed only in patients who received treatment (p = 0.03), but not in those with spontaneous remission.

Conclusions

We come to the conclusion, that low initial 8-IP may be a positive prognostic factor. A decrease of 8-IP in treated patients reflects a non-specific effect of treatment and is not related to mere regression of disease.

Airway wall expression of OX40/OX40L and interleukin-4 in asthma

BACKGROUND

The costimulatory molecule OX40 and its ligand, OX40L, mediate key aspects of allergic airway inflammation in animal models of asthma, including eosinophilic airway inflammation, airway hyperresponsiveness, and T helper 2 polarization. We sought to examine OX40/OX40L and interleukin (IL)-4 expression in asthma across severities.

METHODS

Bronchial biopsies were obtained from 27 subjects with asthma (mild Global Initiative for Asthma [GINA] 1 [n = 10], moderate GINA 2-3 [n = 7], and severe GINA 4-5 [n = 10]) and 13 healthy controls. The number of OX40(+), OX40L(+), IL-4(+), and IL-4 receptor alpha (IL-4Ralpha)(+) cells in the lamina propria and airway smooth muscle (ASM) bundle and the intensity of IL-4Ralpha(+) expression by the ASM were assessed.

RESULTS

The number of OX40(+), OX40L(+), and IL-4(+) cells in the lamina propria and OX40(+) and IL-4(+) cells in the ASM bundle was significantly increased in subjects with mild asthma, but not in those with moderate or severe asthma, compared with healthy controls. In the subjects with asthma, OX40/OX40L expression was positively correlated with the number of eosinophils and IL-4(+) cells in the lamina propria. The number of IL-4Ralpha(+) cells in the lamina propria was significantly increased in moderate-to-severe disease, but not in mild asthma, compared with controls. IL-4Ralpha expression by the ASM bundle was not different among groups.

CONCLUSIONS

OX40/OX40L expression is increased in the bronchial submucosa in mild asthma, but not in moderate-to-severe disease, and is related to the degree of tissue eosinophilia and IL-4 expression. Whether these costimulatory molecules have a role as targets for asthma requires further investigation.

Bronchoscopic evaluation of the mediastinum using endobronchial ultrasound: a description of the first 216 cases carried out at an Australian tertiary hospital

BACKGROUND

Performance of linear probe endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for staging non-small-cell lung cancer has been extensively studied. Alternate indications for its use are less well characterised, and performance in other clinical settings may differ.

METHODS

We examined a prospectively collected cohort comprising the first 215 patients undergoing EBUS-TBNA at our institution. Patients were analysed according to the clinical and radiological indication for referral. We also examined the effect of the procedural learning curve on diagnostic sensitivity.

RESULTS

A total of 215 patients underwent 216 EBUS-TBNA procedures. EBUS-TBNA returned adequate tissue for cytopathological analysis in 202 of 216 procedures (94%). Overall sensitivity for detection of malignancy was 0.92 (95% confidence interval 0.86-0.96); however, this varied according to the primary indication for EBUS-TBNA. Diagnostic sensitivity was high among all sub-groups, but the negative predictive value varied depending on the clinical indication for the procedure. We estimate 104 invasive surgical procedures and 32 inpatient admissions were avoided by use of EBUS-TBNA. Significant improvement in diagnostic performance was seen after 20 procedures were completed, and diagnostic accuracy did not peak until after 50 procedures.

CONCLUSIONS

EBUS-TBNA is able to confirm accurately histologically a large number of disease processes, both malignant and benign, in all clinical indications studied. The procedure is safe even when carried out by proceduralists with minimal prior experience. Diagnostic performance continues to improve beyond 50 cases carried out.

Non-invasive mechanical ventilation for diagnostic bronchoscopy using a new face mask: an observational feasibility study

Purpose

Bronchoscopy is an indispensable tool for invasive pulmonary evaluation with high diagnostic yield and low incidence of major complications. However, hypoxemia increases the risk of complications, in particular after bronchoalveolar lavage. Non-invasive positive pressure ventilation may prevent hypoxemia associated with bronchoalveolar lavage. The purpose of this study is to present a modified total face mask to aid bronchoscopy during non-invasive positive pressure ventilation.

Methods

A commercially available full face mask was modified to allow introduction of the bronchoscope without interfering with the ventilator circuit. Bronchoscopy with bronchoalveolar lavage was performed in 12 hypoxemic non-ICU patients during non-invasive positive pressure ventilation in the ICU.

Results

Patients had severely impaired oxygen uptake as indicated by PaO₂/FiO₂ ratio 192  ± 23 mmHg before bronchoscopy. Oxygenation improved after initiation of non-invasive positive pressure ventilation. In all patients the procedure could be completed without subsequent complications, although in one patient SpO₂ decreased until 86% during bronchoscopy. A microbiological diagnosis could be established in 8 of 12 patients with suspected for infection.

Conclusions

Our modified face mask for non-invasive positive pressure ventilation is a valuable tool to aid diagnostic bronchoscopy in hypoxemic patients.

Bronchial epithelial cells cultured from clinically stable lung allograft patients promote the development of macrophages from monocytes rather than dendritic cells

BACKGROUND

It is understood that chronic allograft failure occurs as a result of alloimmune and non-alloimmune injury. Dendritic cells (DC) are thought to be crucial in regulating (allo)immune airway damage and interactions with epithelial cells are likely. Studies in human lung transplantation are limited, however, and the available literature on DC is inconsistent. This study focused on the ex vivo influence of primary bronchial epithelial cells derived from lung allografts on DC differentiation.

METHODS

Epithelial cell conditioned media (ECCM) were added to monocytes differentiating into DC under the influence of interleukin-4 and granulocyte macrophage-colony stimulating factor. The resultant cells were compared with DC cultured without ECCM and with monocyte-derived macrophages. Expression of typical DC (eg, CD1a) and macrophage (eg, CD14) markers was assessed by flow cytometry. Phenotypical assessments were complemented by functional studies of mannose receptor-mediated phagocytosis (FITC-dextran uptake) and antigen-presenting capability (mixed lymphocyte reactions).

RESULTS

Cells exposed to ECCM expressed significantly lower levels of CD1a than unexposed DC. CD14 expression and phagocytic function were increased. ECCM cultured cells also expressed lower levels of T cell co-stimulatory molecules, secreted an anti-inflammatory cytokine profile and had significantly reduced antigen-presenting capability.

CONCLUSION

Using phenotypic and functional approaches, this study has shown that ECCM from lung allografts drives the production of macrophage-like cells from monocytes rather than DC. The data suggest that epithelial cells may restrain airway DC and potential alloimmunity. It is unclear whether the observed effect is specifically seen in lung transplant recipients or is a general property of bronchial epithelial cells. This may reflect a homeostatic inter-relationship between airway epithelial and DC populations relevant both to lung allografts and the lung more generally.

Granulocyte-macrophage colony-stimulating factor expression in induced sputum and bronchial mucosa in asthma and COPD

Background:

Granulocyte–macrophage colony-stimulating factor (GM-CSF) has been implicated as an important mediator in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). However, the expression of GM-CSF and its receptor in airway samples in asthma and COPD across disease severity needs to be further defined.

Methods:

Sputum GM-CSF was measured in 18 control subjects, 45 subjects with asthma and 47 subjects with COPD. Enumeration of GM-CSF+ cells in the bronchial submucosa and airway smooth muscle bundle was performed in 29 control subjects, 36 subjects with asthma and 10 subjects with COPD.

Results:

The proportion of subjects with measurable GM-CSF in the sputum was raised in those with moderate (7/14) and severe (11/18) asthma, and in those with COPD GOLD (Global Initiative for Chronic Obstructive Lung Disease) stage II (7/16), III (8/17) and IV (7/14) compared with controls (1/18) and those with mild asthma (0/13); p = 0.001. The sputum GM-CSF concentration was correlated with the sputum eosinophilia in subjects with moderate to severe asthma (r_s = 0.41; p = 0.018). The median (interquartile range) GM-CSF+ and GM-CSFR+ cells/mm² of submucosa was increased in severe asthma (1.4 (3.0) and 2.1 (8.4)) compared with those with mild to moderate asthma (0 (2.5) and 1.1 (5)) and healthy controls (0 (0.5) and 0 (1.6)), (p = 0.004 and p = 0.02, respectively).

Conclusions:

The findings support a potential role for GM-CSF in asthma and COPD and suggest that overexpression of GM-CSF in sputum and the bronchial mucosa is a particular feature of severe asthma.

Fibrocyte localization to the airway smooth muscle is a feature of asthma

BACKGROUND

Airway smooth muscle (ASM) hyperplasia is a hallmark of asthma that is associated with disease severity and persistent airflow obstruction.

OBJECTIVES

We sought to investigate whether fibrocytes, a population of peripheral blood mesenchymal progenitors, are recruited to the ASM compartment in asthma.

METHODS

We assessed the number of fibrocytes in bronchial biopsy specimens and peripheral blood from subjects with mild-to-severe refractory asthma versus healthy control subjects. In vitro we investigated potential mechanisms controlling fibrocyte migration toward the ASM bundle.

RESULTS

Fifty-one subjects with asthma and 33 control subjects were studied. In bronchial biopsy specimens, the number of fibrocytes was increased in the lamina propria of subjects with severe refractory asthma (median [interquartile range] number, 1.9/mm(2) [1.7/mm(2)]) versus healthy control subjects (median [interquartile range] number, 0/mm(2) [0.3/mm(2)], P < .0001) and in the ASM bundle of subjects with asthma of all severities (subjects with severe asthma, median [interquartile range] number, 3.8/mm(2) [9.4/mm(2)]; subjects with mild-to-moderate asthma, median [interquartile range] number, 1.1/mm(2) [2.4/mm(2)]); healthy control subjects, (median [interquartile range] number, 0/mm(2) [0/mm(2)]); P = .0004). In the peripheral blood the fibrocyte number was also increased in subjects with severe refractory asthma (median [interquartile range] number, 1.4 x 10(4)/mL [2.6 x 10(4)/mL]) versus healthy control subjects (median [interquartile range] number, 0.4 x 10(4)/mL [1.0 x 10(4)/mL], P = .002). We identified that in vitro ASM promotes fibrocyte chemotaxis and chemokinesis (distance of migration after 4.5 hours, 31 microm [2.9 microm] vs 17 microm [2.4 microm], P = .0001), which was in part mediated by platelet-derived growth factor (mean inhibition by neutralizing antibody, 16% [95% CI, 2% to 32%], P = .03) but not by activation of chemokine receptors.

CONCLUSION

This study provides the first evidence that fibrocytes are present in the ASM compartment in asthma and that ASM can augment fibrocyte migration. The importance of fibrocytes in the development of ASM hyperplasia and airway dysfunction in asthma remains to be determined.

Bronchial hyper-responsiveness, subepithelial fibrosis, and transforming growth factor-beta(1) expression in patients with long-standing and recently diagnosed asthma

INTRODUCTION

Chronic inflammation in asthmatic airways leads to bronchial hyper-responsiveness (BHR) and the development of structural changes. Important features of remodeling include the formation of subepithelial fibrosis due to increased collagen deposition in the reticular basement membrane. Transforming growth factor (TGF)-beta might be a central mediator of tissue fibrosis and remodeling.

MATERIALS AND METHODS

Immunohistochemistry was used to measure collagen III deposition and TGF-beta(1) expression in biopsies from patients with long-standing asthma treated with inhaled corticosteroids, patients with recently diagnosed asthma, and control subjects. Computer-assisted image analysis was used to evaluate total basement membrane (TBM) thickness.

RESULTS

Asthmatics, particularly those with long-standing asthma, had thicker TBMs than healthy subjects. Collagen III deposition was comparable in the studied groups. BHR was not correlated with features of mucosal inflammation and was lower in steroid-treated patients with long-standing asthma than in subjects with newly diagnosed asthma untreated with steroids. Epithelial TGF-beta(1) expression negatively correlated with collagen III deposition and TBM thickness.

CONCLUSIONS

The study showed that TBM thickness, but not collagen III deposition, could be a differentiating marker of asthmatics of different disease duration and treatment. The lack of correlation between BHR and features of mucosal inflammation suggests the complexity of BHR development. Corticosteroids can reduce BHR in asthmatics, but it seems to be less effective in reducing subepithelial fibrosis. The role of epithelial TGF-beta(1) needs to be further investigated since the possibility that it plays a protective and anti-inflammatory role in asthmatic airways cannot be excluded.

Mast cells promote airway smooth muscle cell differentiation via autocrine up-regulation of TGF-beta 1

Asthma is a major cause of morbidity and mortality worldwide. It is characterized by airway dysfunction and inflammation. A key determinant of the asthma phenotype is infiltration of airway smooth muscle bundles by activated mast cells. We hypothesized that interactions between these cells promotes airway smooth muscle differentiation into a more contractile phenotype. In vitro coculture of human airway smooth muscle cells with beta-tryptase, or mast cells with or without IgE/anti-IgE activation, increased airway smooth muscle-derived TGF-beta1 secretion, alpha-smooth muscle actin expression and agonist-provoked contraction. This promotion to a more contractile phenotype was inhibited by both the serine protease inhibitor leupeptin and TGF-beta1 neutralization, suggesting that the observed airway smooth muscle differentiation was driven by the autocrine release of TGF-beta1 in response to activation by mast cell beta-tryptase. Importantly, in vivo we found that in bronchial mucosal biopsies from asthmatics the intensity of alpha-smooth muscle actin expression was strongly related to the number of mast cells within or adjacent to an airway smooth muscle bundle. These findings suggest that mast cell localization in the airway smooth muscle bundle promotes airway smooth muscle cell differentiation into a more contractile phenotype, thus contributing to the disordered airway physiology that characterizes asthma.

Airway hyperresponsiveness is dissociated from airway wall structural remodeling

BACKGROUND

Nonasthmatic eosinophilic bronchitis (EB) has emerged as a useful tool to study the structural and inflammatory mechanisms of airway hyperresponsiveness (AHR) in asthma. We have previously shown that vascular remodeling and reticular basement membrane (RBM) thickening are present in EB. However, it is not known whether other features of structural remodeling including increased airway smooth muscle (ASM) mass, matrix deposition, and glandular hyperplasia are also present in EB.

OBJECTIVES

We sought to determine whether structural remodeling occurs in EB and is associated with AHR and airflow limitation.

METHODS

Forty-two patients with asthma, 21 patients with EB, and 19 healthy volunteers were recruited. ASM area, RBM thickness, collagen 3 deposition, glandular area, mast cells, and granulocytes were assessed in bronchial biopsy samples.

RESULTS

Nonasthmatic eosinophilic bronchitis and asthma were associated with a significant increase in ASM mass and RBM thickness compared with healthy subjects. In contrast, we did not observe any significant differences in collagen 3 deposition in the lamina propria and ASM or the % area of glands in the lamina propria. Univariate analysis demonstrated that mast cell numbers in the ASM were the only feature of remodeling associated with AHR (beta = -0.51; P = .004). Stepwise linear regression revealed that a combination of mast cell numbers in the ASM (beta = -0.43) and disease duration (beta = -0.25; model-adjusted R(2) = 0.26; P = .027) best modeled AHR.

CONCLUSION

Mast cell localization to the ASM bundle, but not structural remodeling of the airway wall, is associated with AHR in asthma.

[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.

Increased sputum and bronchial biopsy IL-13 expression in severe asthma

BACKGROUND

The importance of IL-13 in the asthma paradigm is supported by increased expression in human subjects, particularly in patients with mild-to-moderate asthma. However, the role of IL-13 in severe asthma needs to be further defined.

OBJECTIVE

We sought to assess IL-13 expression in sputum and bronchial biopsy specimens from subjects with mild-to-severe asthma.

METHODS

Sputum IL-13 concentrations were measured in 32 control subjects, 34 subjects with mild asthma, 21 subjects with moderate asthma, and 26 subjects with severe asthma. Enumeration of mast cells, eosinophils, and IL-13+ cells in the bronchial submucosa and airway smooth muscle (ASM) bundle was performed in 7 control subjects, 14 subjects with mild asthma, 7 subjects with moderate asthma, and 7 subjects with severe asthma.

RESULTS

The proportion of subjects with measurable IL-13 in the sputum was increased in the mild asthma group (15/34) and severe asthma group (10/26) compared with that seen in the control group (4/32; P = .004). IL-13+ cells were increased within the submucosa in all asthma severity groups compared with control subjects (P = .006). The number of IL-13+ cells were increased within the ASM bundle in the severe asthma group compared with that seen in the other groups (P < .05). Asthma control questionnaire scores positively correlated with sputum IL-13 concentrations (R(s) = 0.35, P = .04) and mast cells in the ASM bundle (R(s) = 0.7, P = .007). IL-13+ cells within the submucosa and ASM correlated with sputum eosinophilia (R(s) = 0.4, P < or = .05).

CONCLUSIONS

IL-13 overexpression in sputum and bronchial biopsy specimens is a feature of severe asthma.

Realistic and affordable lo-fidelity model for learning bronchoscopic transbronchial needle aspiration

BACKGROUND

Transbronchial needle aspiration (TBNA) is used to sample mediastinal abnormalities and lymph node stations for diagnostic purposes and lung cancer staging. The procedure is underused, operator dependent, and reputed to have a steep learning curve. Other difficulties arise from a bronchoscopist's failure to insert the needle satisfactorily into the target node. The purpose of this study was to evaluate the realism and helpfulness of a lo-fidelity, easily constructed hybrid model used for learning and practicing TBNA.

METHODS

The model is constructed by attaching a porcine tracheobronchial tree to a Laerdal Airway Model mounted on polyvinyl chloride (PVC) piping. Twelve individuals with various levels of bronchoscopy training and experience were given a 15-min introductory PowerPoint presentation on TBNA strategy and planning, execution, and response to complications. Participants then practiced TBNA alone and with guidance, aided by an assistant, as many times as individually necessary to feel comfortable with the procedure. A five-point Likert scale 8-item questionnaire was then completed.

RESULTS

Participants were unanimously positive about their experience (mean scores 4.25-4.91). The model was realistic, provided increased comfort with TBNA techniques, and allowed practice of communication skills.

CONCLUSION

This realistic, affordable, and easily constructed hybrid lo-fidelity airway model allows beginner and experienced bronchoscopists opportunities to learn and practice basic TBNA techniques and team communication skills without placing patients at risk.

The presence of rhinovirus in lower airways of patients with bronchial asthma

RATIONALE

The common cold virus, human rhinovirus (HRV), is the most frequent cause of asthma exacerbations. However, a possible contribution of HRV to the pathogenesis of chronic, persistent asthma has not been defined.

OBJECTIVES

To determine if patients with stable asthma, who are free of clinical signs of a respiratory infection for at least 3 weeks, harbor HRV in their bronchi more frequently than nonasthmatic control subjects, and whether clinical features of asthma are associated with the presence of HRV.

METHODS

Immunohistochemistry and the indirect in situ reverse transcription-polymerase chain reaction method were used to detect the presence of HRV in bronchial mucosal biopsies in patients with asthma and nonasthmatic control subjects.

MEASUREMENTS AND MAIN RESULTS

HRV was found by immunohistochemistry in 9 of 14 bronchial biopsies from subjects with asthma (64.3%) and 2 of 6 nonasthmatic control subjects (33.3%) (P = 0.38). With the more sensitive indirect in situ reverse transcription-polymerase chain reaction method, HRV was found in the mucosal biopsies of 73% of patients with asthma and 22% of nonasthmatic control subjects (P < 0.001). Subjects positive for HRV had lower pulmonary function, higher numbers of blood eosinophils and leukocytes, and eosinophilic infiltration in bronchial mucosa.

CONCLUSIONS

HRV was detected in the lower airway tissue of patients with asthma significantly more often than in nonasthmatic subjects, and its presence was associated with clinical features of more severe disease.

Predictors of diagnostic yield in bronchoscopy: a retrospective cohort study comparing different combinations of sampling techniques

BACKGROUND

The reported diagnostic yield from bronchoscopies in patients with lung cancer varies greatly. The optimal combination of sampling techniques has not been finally established. The objectives of this study were to find the predictors of diagnostic yield in bronchoscopy and to evaluate different combinations of sampling techniques.

METHODS

All bronchoscopies performed on suspicion of lung malignancy in 2003 and 2004 were reviewed, and 363 patients with proven malignant lung disease were included in the study. Sampling techniques performed were biopsy, transbronchial needle aspiration (TBNA), brushing, small volume lavage (SVL), and aspiration of fluid from the entire procedure. Logistic regression analyses were adjusted for sex, age, endobronchial visibility, localization (lobe), distance from carina, and tumor size.

RESULTS

The adjusted odds ratios (OR) with 95% confidence intervals (CI) for a positive diagnostic yield through all procedures were 17.0 (8.5-34.0) for endobronchial lesions, and 2.6 (1.3-5.2) for constriction/compression, compared to non-visible lesions; 3.8 (1.3-10.7) for lesions > 4 cm, 6.7 (2.1-21.8) for lesions 3-4 cm, and 2.5 (0.8-7.9) for lesions 2-3 cm compared with lesions <= 2 cm. The combined diagnostic yield of biopsy and TBNA was 83.7% for endobronchial lesions and 54.2% for the combined group without visible lesions. This was superior to either technique alone, whereas additional brushing, SVL, and aspiration did not significantly increase the diagnostic yield.

CONCLUSION

In patients with malignant lung disease, visible lesions and larger tumor size were significant predictors of higher diagnostic yield, after adjustment for sex, age, distance from carina, side and lobe. The combined diagnostic yield of biopsy and TBNA was significant higher than with either technique alone.

[Follow-up criteria for community acquired pneumonias and acute exacerbations of chronic obstructive pulmonary disease]

The follow-up of Community Acquired Pneumonias (CAP) and Acute Exacerbations of Chronic Obstructive Pulmonary Diseases (AECOPD) differs with the setting of care, but overall calls upon the same investigations as the initial evaluations. In the event of initial ambulatory care, the evaluation is carried out primarily on clinical data, at the 2 or 3rd day for the CAP, at the 2nd to 5th day for the AECOPD. In the event of unfavourable evolution, or from the start in the most severe cases, the follow-up is carried out in hospital; clinical evaluation is readily daily, and all the more frequent that the clinical condition is worrying because of the severity or risk factors. The investigations will be limited to those initially abnormal in the event of favourable evolution; on the contrary, unfavourable evolution can justify new investigations which depend on clinical characteristics. Remotely, i.e. 4 to 8 weeks later, must be checked the return at the baseline clinical state, a chest X-ray (CAP), spirometry and arterial blood gas (AECOPD), even bronchoscopy and thoracic CT-scan.

Nosocomial outbreak of Pseudomonas aeruginosa infections related to a flexible bronchoscope

An outbreak of Pseudomonas aeruginosa infections affecting 17 patients was detected in the 27-bed intensive care unit (ICU) of a community hospital from 1 July to 30 September 2003. An ambidirectional cohort study was conducted to identify the risk factors for infection. Nosocomial infections were defined using the criteria of the Centers for Disease Control and Prevention. Random arbitrary polymorphic DNA-polymerase chain reaction was used for genotypic characterization. Logistic regression analyses demonstrated that case patients were more likely than non-cases to have had a longer stay in the ICU, and to have undergone mechanical ventilation and antimicrobial treatment. The multi-variate analysis identified recent bronchoscopy [risk ratio (RR) 3.8, 95% confidence interval (CI) 2.5-3.9] and exposure to an infected patient (RR 2.9, 95% CI 1.1-3.7) as independent risk factors. Molecular analysis showed that of the nine isolates available, four patients had a similar strain. The factor with the strongest influence on the risk of death was infection with P. aeruginosa (RR 2.1, 95% CI 1.0-2.4, P=0.04). A combined infection control strategy was implemented, including strict compliance with isolation precautions and recommendations for cleaning and disinfecting bronchoscopes, and a sharp reduction in the incidence of P. aeruginosa infection followed. It is thought that this outbreak was caused by patient-to-patient transmission and infection from a common source, i.e. the flexible bronchoscope.

Interstitial lung disease: progress and problems

Interstitial lung disease involves all areas of medicine as it often occurs in patients with comorbidities or as a consequence of systemic diseases and their treatment. Typically the physician is faced with a breathless patient, a diffusely abnormal chest radiograph, and a wide differential diagnosis. Progress has been made in using high resolution computed tomography as the key investigation in characterising the pattern and extent of the disease. Bronchoalveolar lavage is particularly important in excluding infection as a cause of diffuse lung infiltrates. Surgical lung biopsies have led to a new classification system for the range of histopathological patterns of disease that were previously known by the collective term cryptogenic fibrosing alveolitis. Problems persist in deciding when a surgical lung biopsy is clinically justified, in understanding the pathogenesis of these diseases, and in finding more effective treatments.

Ameba-associated microorganisms and diagnosis of nosocomial pneumonia

Ameba-associated microorganisms should be suspected when conventional microbiologic test results are negative.

To elucidate the role of ameba-associated microorganisms (AAMs) as etiologic agents of pneumonia, we screened for Legionella spp., Parachlamydia acanthamoeba, Afipia sp., Bosea spp., Bradyrhizobium spp., Mesorhizobium amorphae, Rasbo bacterium, Azorhizobium caulinodans, Acanthamoeba polyphaga mimivirus, and conventional microorganisms in 210 pneumonia patients in intensive-care units by using culture, polymerase chain reaction, and serologic testing. These resulted in 59 diagnoses in 40 patients. AAMs and non-AAMs were implicated in 10.5% of the patients. The infectious agents were identified in 15 patients: Acanthamoeba polyphaga mimivirus, 8; Legionella pneumophila, 3; L. anisa, 1; Parachlamydia sp., 1; Bosea massiliensis, L. worsleiensis, L. quinlivanii, and L. rubrilucens, 1; and M. amorphae and R. bacterium, 1. A. polyphaga mimivirus was the fourth most common etiologic agent, with a higher seroprevalence than noted in healthy controls. This finding suggested its clinical relevance. Therefore, AAM might cause nosocomial pneumonia and should be suspected when conventional microbiologic results are negative.

Effective nonanatomical endoscopy training produces clinical airway endoscopy proficiency

We studied the effectiveness of two nonanatomical endoscopic dexterity training models: "Choose the Hole" and Dexter. Effectiveness was assessed in terms of time spent training, subjective rating, performance on an anatomical manikin, and clinical performance on fellow participants who acted as awake subjects. Forty-three anesthesia specialists, trainees, and technicians volunteered. Performances were videotaped, timed, and scored with a Global Rating Scale (GRS) from 1 (very poor) to 5 (clearly superior). The Dexter group spent more time training than the Choose the Hole group (median time [range], 152 min [70-510 min] versus 75 min [17-281 min]; P < 0.01). Subjective ratings were better in the Dexter group. In clinical bronchoscopy, the Dexter group was faster (30.7 s [17.1-43.5 s] versus 36.6 s [22.8-105.1 s]; P = 0.02) and had higher GRS scores (mean [sd]: 3.0 [0.4] versus 2.6 [0.6]; P = 0.04), indicating superior performance. Clinical and manikin performance (GRS scores) were significantly correlated (rho = 0.62; P = 0.0001). Benchmark levels of clinical bronchoscopic performance can be anticipated from bench model performance without a clinical learning curve. Dexter is a more effective model for learning endoscopic dexterity than the Choose the Hole model. Airway topicalization with lidocaine in a dose range consistent with published series (490-980 mg or 7.14-14.77 mg/kg) resulted in a frequent incidence of side effects. No major adverse events occurred.

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.

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.