A novel gelatinized barium sulfate injection method for assessment of bronchoalveolar lavage parameters.

INTRODUCTION: Bronchoalveolar lavage (BAL) is frequently used in pulmonary medicine though it requires further optimization. Practical obstacles such as patient safety and procedural limitation have to date precluded large, controlled trials aimed at standardization of BAL procedure. Indeed, BAL guidelines are based on observational data. Innovative research methods are necessary to advance the clinical practice of BAL. METHODS: In our study, we evaluated the effect of injecting a gelatinized barium solution into different lobes and segments of cadaveric lungs. As the technique requires an irreversible injection into lung airspaces, it is not suitable for in vivo purposes. We measured the volume returned from BAL as well as the distribution of BAL injection via dissection. Segmental anatomic orientation was compared to a radiologist's impression of plain film radiographs taken of injected lungs. RESULTS: Mean injected volume distributions were greatest in the upper lobes and lowest in the lower lobes; mean ratios of injected volume distribution to lung lobe volume also followed this trend. Cannulated bronchi orders favored lower branches in the upper lobe and higher branches in the lower lobes. Segmental anatomy varied by the lung lobe injected and was most varied in the lower lobes. CONCLUSION: This novel gelatinized-barium injection technique provides a minimally complex method to yield clinically meaningful feedback on the performance of BAL. The technique is also adaptable to study of procedural parameters in the context of variable lung anatomies and pathologies.

Assessment of an automated Cytomegalovirus nucleic acid amplification test using clinical plasma, bronchoalveolar lavage, and tissue specimens.

BACKGROUND: Cytomegalovirus (CMV) causes significant morbidity and mortality in immunocompromised patients, particularly transplant recipients. Quantitation of CMV DNA in peripheral blood is used to monitor prophylactic and pre-emptive approaches to prevent CMV disease, whereas CMV DNA testing of non-plasma specimens may aid in the diagnosis of end-organ disease. METHODS: The analytical performance of the FDA-approved Aptima CMV Quant Assay was evaluated using reference CMV (SeraCare) diluted in defibrinated human plasma, as well as negative bronchoalveolar lavage fluid and tissue. Agreement was determined using 100 clinical acid-citrate-dextrose (ACD) plasma specimens, 77 bronchoalveolar lavage (BAL) fluids, and 101 tissues previously tested using artus CMV qPCR. RESULTS: Aptima CMV lower limit of detection (LLOD) was 169 IU/mL for ACD plasma, 100 IU/mL for BAL, and 50 IU/mL for tissue. Positive percent agreement (PPA) was 100.0% (50/50; 95% CI: 92.9% - 100.0%) and negative percent agreement (NPA) was 94.0% (47/50; 95% CI: 83.5% - 98.8%) for ACD plasma. Bland-Altman analysis revealed a bias of 0.20 log10 IU/mL (Aptima - artus) with 95% limits of agreement of -0.53 to 0.93. For BAL fluids, PPA was 70.0% (14/20; 95% CI: 45.7% - 88.1%) and NPA was 82.4% (43/51; 95% CI: 69.1% - 91.6%). For tissues, PPA was 90.0% (45/50; 95% CI: 78.2% - 96.7%) and NPA was 94.0% (47/50; 95% CI: 83.5% - 98.8%). CONCLUSIONS: The Aptima CMV Quant Assay demonstrates high analytical sensitivity and good overall agreement using clinical plasma and tissue specimens.

The impact of lung ultrasound assessment during a whole lung lavage: A paediatric case of pulmonary alveolar proteinosis.

Whole lung lavage (WLL) is the first-line treatment for pulmonary alveolar proteinosis. We hypothesized that lung ultrasound (LUS) would guide flooding during treatment in a 15-year-old boy. WLL of each lung consisted of instillation of saline followed by kinesiotherapy and fluid drainage. In the first WLL, the lung was repeatedly flooded until the lavage fluid was clear on macroscopic examination. During this process, LUS was used to visualise lung aeration. In the second WLL, we used LUS signs to guide the lavage volume. The appearance of the fluid bronchogram sign showed that saline infusion could be stopped earlier than in the first lavage. In conclusion, LUS helped monitor the different stages of controlled lung de-aeration during WLL and reduce the total amount of saline used. This technique will also reduce the risk of WLL-related complications.

Bronchoalveolar Lavage (BAL) and Pathologic Assessment of Electronic Cigarette or Vaping Product Use-associated Lung Injury (EVALI): The EVALI-BAL Study, A Multicenter Cohort.

BACKGROUND: E-cigarette or vaping-use related acute lung injury (EVALI) is a spectrum of radiographic and histologic patterns consistent with acute to subacute lung injury. However, limited data exist characterizing bronchoalveolar lavage (BAL) findings. The goal of this study is to further define the pathologic findings from BAL and biopsy samples of subjects with EVALI across 7 institutions. METHODS: A multicentered registry of patients admitted with EVALI who underwent flexible bronchoscopy with BAL+/-transbronchial biopsy from July 2019 to April 2021 was compiled for retrospective evaluation from 7 academic institutions throughout the United States. Radiographic and cytopathologic findings and frequencies were correlated with the substance vaped. RESULTS: Data from 21 subjects (42.9% women) who were predominantly White (76.2%) with a median age of 25 years (range, 16 to 68) with EVALI were included in this study. Sixteen patients (76.2%) reported use of tetrahydrocannabinol; the remainder used nicotine. BAL was performed in 19 of the 21 subjects, and transbronchial lung biopsy was performed in 7 subjects. BAL findings revealed neutrophilic predominance (median, 59.5%, range, 3.1 to 98) in most cases. Ten BAL samples demonstrated pulmonary eosinophilia ranging from 0.2% to 49.1% with one subject suggesting a diagnosis of acute eosinophilic pneumonia associated with the use of e-cigarettes. Lipid-laden macrophages were noted in 10 of 15 reports (66.7%). Transbronchial biopsy most frequently demonstrated patterns of organizing pneumonia (57.1%). CONCLUSION: EVALI-associated BAL findings typically demonstrate a spectrum of nonspecific inflammatory changes, including neutrophilia, lipid-laden macrophages, and in some cases eosinophilia.

Caracterización demográfica y clínica de pacientes críticos con neumonía por influenza A H1N1 / Demographic and clinical characterization of critically ill patients with influenza A H1N1 pneumonia

INTRODUCCIÓN. La epidemia de influenza y sus complicaciones profundizaron el estudio de las neumonías virales en cuidados intensivos. En nuestro país hay pocos datos sobre este tema. OBJETIVOS. Realizar una caracterización demográfica y clínica de pacientes críticos con neumonía por Influenza A H1N1 en un hospital de tercer nivel de complejidad. MATERIALES Y MÉTODOS. Estudio observacional, analítico, retrospectivo, con análisis univariante y multivariante. Población de 293 y muestra de 44 datos de historias clínicas electrónicas de pacientes diagnosticados con A H1N1 ingresados a la Unidad de cuidados intensivos del Hospital de Especialidades Carlos Andrade Marín en el período enero 2016 a diciembre de 2018. Como criterios de inclusión se consideró a todos los pacientes adultos mayores de 18 años que ingresaron a la UCI, con el diagnóstico de neumonía comunitaria grave con confirmación por reacción de cadena de polimerasa en tiempo real para influenza A H1N1 en hisopado nasal o aspirado traqueal. Se excluyó a pacientes embarazadas con diagnóstico de influenza A H1N1, pacientes con más de 48 horas de ingreso hospitalario previo a su ingreso a UCI, pacientes con datos insuficientes en los registros. Los datos se obtuvieron del sistema AS-400. El análisis estadístico se realizó en el programa Statistical Package for Social Sciences, versión 22. El nivel de significación fue una p<0.05. RESULTADOS. La prevalencia en pacientes críticos de neumonía por influenza A H1N1 durante 2016-2018 fue de 16,72%, la mediana de edad fue de 55 años, 25% masculinos, 34% obesos, 34% con hipertensión arterial. Escala "Acute Physiology and Chronic Health Evaluation II" 23,50, "Simplified Acute Physiologic Score III" 54, "Sepsis related Organ Failure Assessment" 11,50, Lactato deshidrogenasa 99,50, Procalcitonina 0,99; 9 días de ventilación mecánica invasiva, 10,50 días de estancia en la unidad. El 91% presentó shock séptico, 59% lesión renal aguda. El 89% tuvo Síndrome de Distrés Respiratorio del Adultos, 69% fue grave, 87% usó ventilación mecánica, 38,50% corticoides, 36% posición prona, Presión parcial de oxígeno/Fracción inspirada de oxígeno 74, volumen tidal/kilogramo de 7 mililitros, presión plateau de 27,50 centímetros de agua. La mortalidad general en la Unidad de Cuidados Intensivos fue de 38,63% y a los 28 días de 63,60%, en shock séptico fue 42,50% y en Síndrome de Distrés Respiratorio del Adultos del 41,02%. El análisis de regresión logística multivariable identificó como factores independientes asociados a mortalidad el incremento de Lactato deshidrogenasa (OR 2,69, 9% IC 1,090-6,642) y Procalcitonina (OR 2,51, IC 1,005-6,272). CONCLUSIONES. Las características, frecuencia y mortalidad de este grupo de pacientes críticos con neumonía por influenza A H1N1 son similares a lo reportado en la literatura mundial.

INTRODUCTION. The influenza epidemic and its complications deepened the study of viral pneumonias in intensive care. In our country there is little data on this subject. OBJECTIVES. To perform a demographic and clinical characterization of critical patients with pneumonia due to pneumonia due to Influenza A H1N1 in a third level hospital. MATERIALS AND METHODS. Observational, analytical, retrospective study, with univariate and multivariate analysis. We compared the groups of dead patients and survivors. The significance level was p<0,05. RESULTS. The prevalence in critically ill patients of influenza A H1N1 pneumonia during 2016-2018 was 16,72%, 44 cases were collected, median age 55 years, 25% male, 34% obese, 34% with arterial hypertension. APACHE II 23,50, SAPS III 54, SOFA 11,50, LDH 99,50, PCT 0,99, 9 days of invasive mechanical ventilation, 10,50 days of unit stay. 91% presented septic shock, 59% with acute kidney injury 89% had ARDS, 69% were severe, 87% used mechanical ventilation, 38,50% corticosteroids, 36% prone position, PaO2/FiO2 74, tidal volume/kg of 7 ml, plateau pressure of 27,50 cmH2O. Overall mortality in the ICU was 38,63% and at 28 days was 63,60%, in septic shock it was 42,50% and in Adult Respiratory Distress Syndrome it was 42,50%. was 42,50% and 41,02% in Adult Respiratory Distress Syndrome. The ultivariate logistic regression analysis identified as independent factors associated with mortality, the increase in LDH (OR 2,69, 9% CI 1,090-6,642) and PCT (OR 2,51, CI 1,005-6,272). CONCLUSIONS. The characteristics, frequency and mortality of this group of critical patients with pneumonia due to influenza A H1N1 are similar to those reported in the world literature.

External quality assessment of flow cytometric bronchoalveolar lavage cellular analysis: 20 years' experience in The Netherlands.

BACKGROUND: Bronchoalveolar (BAL) cellular analysis can be supportive in the diagnosis of interstitial lung disease. The flow cytometric analysis of BAL fluid cells is complicated by cell fragility and adherence and autofluorescence of macrophages, making conventional analysis of BAL fluid cells as done in external quality schemes (EQA) for blood lymphocyte subsets, not representative. Following a procedure for stabilized BAL cells, a separate EQA was set up. The results of 20 years' experience are presented. METHODS: From each round between 2000 and 2020 the following flow cytometric parameters were recorded from each participant: total lymphocyte population (TLY), CD3+ lymphocytes, CD3+ CD4+ lymphocytes, CD3+ CD8+ lymphocytes, CD3- CD16+/56+ lymphocytes, CD19+ lymphocytes and CD103 + CD3+ lymphocytes. In addition, the eosinophils and neutrophils were recorded. The mean and standard deviation of each parameter per round were calculated. The 40 rounds were divided in four respective groups of 10 in order to compare the results as function of time. In addition the interpretation of the results of participants was scored. RESULTS: The median SD in the four groups was below 10% for all parameters except for TLY and the CD103+ CD3+ lymphocytes. No improvement in time was observed for any (sub)population except for the CD3+ CD4+ subset. Interpretation of the results varied based on disease, with greatest consensus for sarcoidosis cases and lowest for nonspecific interstitial lung disease cases. CONCLUSIONS: A dedicated EQA for BAL fluid cellular analysis appears to be justified as the test material is substantially different from that of peripheral blood. We show that adequate analytical and post-analytical quality control can be achieved.

Aspiration and Inspiration: Using Bronchoalveolar Lavage for Toxicity Assessment.

Bronchoalveolar lavage (BAL) is a simple procedure that is used to investigate drug efficacy or lung toxicity. It is sensitive to lung changes and less invasive than histological evaluation. It can be performed repeatedly at interim time points or as a terminal procedure. Airborne contaminants and purposely inhaled compounds, resident and inflammatory cells, as well as different cellular soluble products can be harvested in bronchoalveolar fluid (BALF) and measured. Bronchoalveolar lavage can also be an important tool to understand drug exposure and its metabolism in the lung, although it should be rigorously performed and interpreted with caution, especially in the context of regulated toxicology studies. This review focuses on the methods and uses of BAL in animal research, primarily in the pharmaceutical industry, as well as for the assessment of drugs, pollutants, and chemical lung toxicity. Methods of collecting and analyzing BALF and parameters affecting variability are discussed in detail. Improved automated methods for cell counting and analysis of the inflammatory cellular differential using hematology analyzers, common markers of lung injury, and new methodologies are described. Correlation between BALF and histological evaluation should not be considered as repetitive but as complementary assessments in the context of efficacy and toxicity studies.

Assessment and Management of Occupational Hypersensitivity Pneumonitis.

The diagnosis and treatment of occupational hypersensitivity pneumonitis (OHP) remain complex and challenging in the absence of diagnostic gold standards or clinical guidelines. This review provides an update of the recent literature regarding the different presentations of OHP and the diagnostic yield and value of the diagnostic tests currently available, which include occupational and medical history, laboratory tests (serum-specific immunoglobulins, environmental sampling), imaging, bronchoalveolar lavage, transbronchial biopsy, transbronchial cryobiopsy, surgical lung biopsy, and specific inhalation challenges. These tools provide a precise differential diagnosis within the framework of interstitial lung diseases. However, among the chronic fibrotic forms, distinguishing OHP from sarcoidosis, nonspecific interstitial pneumonia and idiopathic pulmonary fibrosis remains a diagnostic challenge. Avoidance of exposure is pivotal for OHP management, whereas corticosteroids are fundamental in the pharmacological approach to this disease. In addition, studies describing the long-term benefits of immunosuppressive and antifibrotic agents have increased the use of these treatments in OHP.

High levels of inherent variability in microbiological assessment of bronchoalveolar lavage samples from children with persistent bacterial bronchitis and healthy controls.

Bronchoalveolar lavage (BAL) is widely regarded as providing "gold standard" samples for infective lower respiratory tract disease. Current approaches have been adopted empirically without robust assessment and hence carry many assumptions that have not been tested. Many of these uncertainties were highlighted in the ATS pediatric bronchoscopy guidelines. This study was designed to explore some of these issues. BAL was undertaken via an endotracheal tube in 13 subjects aged less than 6 years with persistent bacterial bronchitis and five healthy controls. Aliquots of the same pooled BAL sample were sent to two accredited laboratories. one producing semiquantitative results and the other quantitative results. For five patients potentially pathogenic bacteria were grown by one laboratory but not the other, while in three more there were discrepancies in the organisms reported. Despite being symptomatic and off antibiotics, only 3 of 13 patients were reported to have a pathogen at a density of more than 1 × 104 colony forming unit. There was at best a poor correlation between semiquantitative and quantitative data. Potential pathogens were cultured in two of five control samples. The results suggest that the results from conventional microbiological assessment of BAL samples can be highly variable and that the proposal that a discrete cut-off is of value in patients with chronic endobronchial infection is probably invalid.

Molecular testing on bronchial washings for the diagnosis and predictive assessment of lung cancer.

Cytopathological analyses of bronchial washings (BWs) collected during fibre-optic bronchoscopy are often inconclusive for lung cancer diagnosis. To address this issue, we assessed the suitability of conducting molecular analyses on BWs, with the aim to improve the diagnosis and outcome prediction of lung cancer. The methylation status of RASSF1A, CDH1, DLC1 and PRPH was analysed in BW samples from 91 lung cancer patients and 31 controls, using a novel two-colour droplet digital methylation-specific PCR (ddMSP) technique. Mutations in ALK, BRAF, EGFR, ERBB2, KRAS, MAP2K1, MET, NRAS, PIK3CA, ROS1 and TP53 and gene fusions of ALK, RET and ROS1 were also investigated, using next-generation sequencing on 73 lung cancer patients and 14 tumour-free individuals. Our four-gene methylation panel had significant diagnostic power, with 97% sensitivity and 74% specificity (relative risk, 7.3; odds ratio, 6.1; 95% confidence interval, 12.7-127). In contrast, gene mutation analysis had a remarkable value for predictive, but not for diagnostic, purposes. Actionable mutations in EGFR, HER2 and ROS1 as well as in other cancer genes (KRAS, PIK3CA and TP53) were detected. Concordance with gene mutations uncovered in tumour biopsies was higher than 90%. In addition, bronchial-washing analyses permitted complete patient coverage and the detection of additional actionable mutations. In conclusion, BWs are a useful material on which to perform molecular tests based on gene panels: aberrant gene methylation and mutation analyses could be performed as approaches accompanying current diagnostic and predictive assays during the initial workup phase. This study establishes the grounds for further prospective investigation.

Spontaneous Pneumothorax After Rupture of the Cavity as the Initial Presentation of Tuberculosis in the Emergency Department.

BACKGROUND Spontaneous pneumothorax can be secondary to a wide variety of lung diseases. Spontaneous pneumothorax secondary to pulmonary tuberculosis occurs in rare cases of residual fibrosis with retractions and bullae. CASE REPORT We present the case of a 65-year-old male patient from a rural area in the province of Los Ríos in Babahoyo, Ecuador, with no history of contact with tuberculosis. The patient arrived at the Emergency Department of the Regional Hospital of the Instituto Ecuatoriano de Seguridad Social (IESS), Babahoyo, due to acute respiratory failure, preceded by 10 days of evolution due to cough accompanied by greenish expectoration, chest pain, asthenia, and weight loss. On chest radiography, a left pneumothorax and interstitial pulmonary infiltrate were reported. A chest tube was placed, and the patient was intubated and was placed on invasive mechanical ventilation due to severe respiratory failure. Use of the GeneXpert MTB/RIF System detected Mycobacterium tuberculosis without resistance to rifampicin. Ziehl-Neelsen (ZN) staining for the identification of bacillus acid-resistant alcohol was positive in alveolar bronchial lavage. MALDI-TOF mass spectrometry and phenotypic analysis showed the presence of Pseudomonas aeruginosa and Klebsiella pneumonia with carbapenemases resistance mechanism, and the KPC type enzyme was identified. The culture for Mycobacterium tuberculosis was positive from the fourth week. CONCLUSIONS Secondary pneumothorax due to rupture of the polymicrobial cavity and especially of tuberculous origin is a very special form of acute respiratory failure in patients with previous structural pulmonary lesions in the Emergency Department.

Semiquantitative Ultrasound Assessment of Lung Aeration Correlates With Lung Tissue Inflammation.

We studied the relationship between ultrasound-assessed lung aeration and inflammation in a particular population of ventilated preterm neonates with mild-to-moderate lung inflammation and no congenital heart defect. Lung aeration estimated by a semiquantitative lung ultrasound score significantly correlated with several inflammatory markers both at cellular (neutrophil count in bronchoalveolar lavage: ρ = 0.400, p = 0.018) and molecular level (total proteins: ρ = 0.524, p = 0.021; interleukine-8: ρ = 0.523, p = 0.021; granulocytes-macrophages colony stimulating factor: ρ = 0.493, p = 0.020; all measured in bronchoalveolar lavage and expressed as epithelial lining fluid concentrations). Lung ultrasound might detect changes in lung aeration attributable to mild-to-moderate local inflammation if cardiogenic lung edema is excluded. Thus, it is possible to describe some levels of lung inflammation with semiquantitative lung ultrasound.

Diagnostic Fibreoptic Bronchoscopy at Tribhuvan University Teaching Hospital.

BACKGROUND: Fibreoptic bronchoscopy is one of the most vital procedures performed in health care setting. Globally, several studies have reported findings of fibreoptic bronchoscopy while only few studies have been reported in Nepal. The aim of this study was to perform two year retrospective analysis of diagnostic fibreoptic bronchoscopy at tertiary referral centre. METHODS: A hospital based retrospective observational study was conducted at Tribhuvan University Teaching Hospital, Kathmandu, Nepal. Consecutive bronchoscopy reports from June 2017 to May 2019 were included. Data entry and analysis was done in Microsoft Office Excel 2010. Descriptive statistics was performed to obtain clinico-demographic profile of patients, indications and findings of bronchoscopy. RESULTS: A total of 238 bronchoscopy procedures were analyzed. Mean age of patients was 55.02 years with range from 15 to 84 years. Majority of bronchoscopy were performed in male patients (58%). One hundred and twelve patients (47.05%) had no endobronchial lesion. Endoscopically visible tumor was the most common abnormality seen in 57 (23.9%) patients with highest prevalence in 55-65 years followed by extrinsic compression of bronchial tree seen in 13 (5.5%) patients. Bronchioalveolar lavage for routine examination (n=207) was the most commonly performed procedure during bronchoscopy followed by bronchial biopsy (n=55). CONCLUSIONS: Fibreoptic bronchoscopy is an extremely useful tool for evaluation of tracheobronchial pathology. Baseline bronchoscopic findings from tertiary referral centre in Nepal was obtained in this study.

Characterizing Health Outcomes in Idiopathic Pulmonary Fibrosis using US Health Claims Data.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a life-threatening interstitial lung disease (ILD). Characterizing health outcomes of IPF patients is challenging due to disease rarity. OBJECTIVE: This study aimed to identify the burden of disease in patients newly diagnosed with IPF. METHODS: Patients with ≥1 claim with an IPF diagnosis were identified from a United States healthcare insurer's database (2000-2013). Patients with other known causes of ILD or aged <40 years were excluded. Subgroups were compared based on the 2011 change in International Classification of Diseases, 9th Revision (ICD-9) definition of IPF and occurrence of IPF testing. The prevalence and incidence of preselected health conditions of clinical interest were estimated. RESULTS: Median age of newly diagnosed patients (n = 7,298) was 62 years (54.0% male). Restricting to patients with IPF diagnostic testing did not substantially affect cohort characteristics, nor did ICD-9 IPF coding change. Mean follow-up was 1.7 years; 16.8% of patients died; and a substantial proportion of patients were censored due to end of health plan enrollment (50.7%) and other causes of ILD (19.6%). The incidence of pulmonary hypertension, lung cancer, and claims-based algorithm proxy for acute respiratory worsening of unknown cause was 22.5, 17.6, and 12.6 per 1,000 person-years, respectively. CONCLUSIONS: Patients with IPF had a high disease burden with a variety of health outcomes observed, including a high rate of mortality. Database censoring due to changes in enrollment or other ILD diagnoses limited follow-up. Altering cohort entry definitions, including IPF testing or ICD-9 IPF coding change, had little impact on cohort baseline characteristics.

Flow Cytometry-Based Cell Type-Specific Assessment of Target Regulation by Pulmonary siRNA Delivery.

Pulmonary siRNA delivery has attracted strong interest and has been reported to successfully mediate target gene knockdown in a number of disease models. However, the nature of the epithelial cells that eventually take up siRNA and the question if other lung cell types may also be transfected has so far been neglected. Therefore, we describe here a flow cytometry-based method using transgenic enhanced green fluorescence protein (EGFP) expressing mice for the differentiation of transfected lung cell populations based on their antigen expression.

Metagenomic comparison of tracheal aspirate and mini-bronchial alveolar lavage for assessment of respiratory microbiota.

Accurate and informative microbiological testing is essential for guiding diagnosis and management of pneumonia in patients who are critically ill. Sampling of tracheal aspirate (TA) is less invasive compared with mini-bronchoalveolar lavage (mBAL) and is now recommended as a frontline diagnostic approach in patients who are mechanically ventilated, despite the historical belief that TA was suboptimal due to contamination from oral microbes. Advancements in metagenomic next-generation sequencing (mNGS) now permit assessment of airway microbiota without a need for culture and, as such, provide an opportunity to examine differences between mBAL and TA at a resolution previously unachievable. Here, we engaged shotgun mNGS to assess quantitatively the airway microbiome in matched mBAL and TA specimens from a prospective cohort of critically ill adults. We observed moderate differences between sample types across all subjects; however, we found significant compositional similarity in subjects with bacterial pneumonia, whose microbial communities were characterized by dominant pathogens. In contrast, in patients with noninfectious acute respiratory illnesses, significant differences were observed between sample types. Our findings suggest that TA sampling provides a similar assessment of airway microbiota as more invasive testing by mBAL in patients with pneumonia.

Assessment of Ozone-Induced Lung Injury in Mice.

Ozone is a major pollutant in the air we breathe, and elevated levels lead to significant morbidity and mortality. As the climate warms, levels of ozone are predicted to increase. Accordingly, studies to assess the mechanisms of ozone-induced lung diseases are paramount. This chapter describes mouse models of ozone exposure and methods for assessing the effects of ozone in the lungs. These include bronchoalveolar lavage, necropsy, and measurement of lung function. Lavage allows for assessment of cell infiltration, cytokine production, tissue damage and capillary leakage in the airspaces. Necropsy provides tissue for gene expression, histology, and protein assessment in the whole lung. Lung physiology is used to assess airway hyperresponsiveness, tissue and total lung resistance, compliance, and elastance.

Assessment of BRAFV600E mutation in pulmonary Langerhans cell histiocytosis in tissue biopsies and bronchoalveolar lavages by droplet digital polymerase chain reaction.

The neoplastic nature of pulmonary Langerhans cell histiocytosis (PLCH) is still debated. As the detection of BRAF V600E and MAP2K1 mutations in patients with PCLH is now considered for such assessment, the aim of our study was to evaluate digital droplet polymerase chain reaction (ddPCR) in PCLH diagnosis. We retrospectively analyzed BRAFV600E detection in a cohort of 42 PCLH tissues and 18 bronchoalveolar lavages (BALs) by ddPCR, immunohistochemistry, high-resolution melting PCR (HRM), and next-generation sequencing (NGS). The presence of BRAFV600E mutation was assessed by at least two concordant techniques to further evaluate specificity and sensitivity of each method. The BRAF V600E mutation prevalence was detected in 18 out of 41 cases by ddPCR, 10 out of 36 cases by HRM PCR, and 16 out of 31 cases by NGS. BRAFV600E immunohistochemistry sensitivity was 94%, and specificity was 79%. HRM PCR sensitivity was only 59%, and specificity was 100%. NGS sensitivity and specificity were 100% for interpretable cases (n = 31), but in 11 cases, this technique was non-contributive. The analysis of BAL samples by ddPCR revealed a BRAFV600E mutation both in tissue and in BAL samples in one patient, a wild-type status both in tissue and in BAL samples in two patients, and a wild-type BRAF status in BAL and a BRAFV600E mutation in tissue samples in four patients. The study supports the usefulness of ddPCR for BRAF status assessment in either tissue or BAL samples to increase the accuracy of PLCH diagnosis.

Household air pollution and the lung microbiome of healthy adults in Malawi: a cross-sectional study.

BACKGROUND: Domestic combustion of biomass fuels, such as wood, charcoal, crop residue and dung causes Household Air Pollution (HAP). These inhaled particulates affect more than half of the world's population, causing respiratory problems such as infection and inflammatory lung disease. We examined whether the presence of black carbon in alveolar macrophages was associated with alterations in the lung microbiome in a Malawi population. METHODS: Bronchoalveolar lavage samples from 44 healthy adults were sequenced using 16S rDNA amplification to assess microbial diversity, richness and relative taxa abundance. Individuals were classified as high or low particulate exposure as determined by questionnaire and the percentage of black carbon within their alveolar macrophages. RESULTS: Subjects in the low and high particulate groups did not differ in terms of source of fuels used for cooking or lighting. There was no difference in alpha or beta diversity by particulate group. Neisseria and Streptococcus were significantly more abundant in samples from high particulate exposed individuals, and Tropheryma was found less abundant. Petrobacter abundance was higher in people using biomass fuel for household cooking and lighting, compared with exclusive use of electricity. CONCLUSIONS: Healthy adults in Malawi exposed to higher levels of particulates have higher abundances of potentially pathogenic bacteria (Streptococcus, Neisseria) within their lung microbiome. Domestic biomass fuel use was associated with an uncommon environmental bacterium (Petrobacter) associated with oil-rich niches.

A novel continuous capnodynamic method for cardiac output assessment in a porcine model of lung lavage.

BACKGROUND: We have evaluated a new method for continuous monitoring of effective pulmonary blood flow (COEPBF ), i.e. cardiac output (CO) minus intra-pulmonary shunt, during mechanical ventilation. The method has shown good trending ability during severe hemodynamic challenges in a porcine model with intact lungs. In this study, we further evaluate the COEPBF method in a model of lung lavage. METHODS: COEPBF was compared to a reference method for CO during hemodynamic and PEEP alterations, 5 and 12 cmH2 O, before and after repeated lung lavages in 10 anaesthetised pigs. Bland-Altman, four-quadrant and polar plot methodologies were used to determine agreement and trending ability. RESULTS: After lung lavage at PEEP 5 cmH2 O, the ratio of arterial oxygen partial pressure related to inspired fraction of oxygen significantly decreased. The mean difference (limits of agreement) between methods changed from 0.2 (-1.1 to 1.5) to -0.9 (-3.6 to 1.9) l/min and percentage error increased from 34% to 70%. Trending ability remained good according to the four-quadrant plot (concordance rate 94%), whereas mean angular bias increased from 4° to -16° when using the polar plot methodology. CONCLUSION: Both agreement and precision of COEPBF were impaired in relation to CO when the shunt fraction was increased after lavage at PEEP 5 cmH2 O. However, trending ability remained good as assessed by the four-quadrant plot, whereas the mean polar angle, calculated by the polar plot, was wide.