Bronchoalveolar Lavage Liquid Research Articles

Bronchoalveolar lavage in suspected COVID-19 cases with a negative nasopharyngeal swab: a retrospective cross-sectional study in a high-impact Northern Italy area.

COVID-19 diagnosis relies on molecular testing for SARS-CoV-2 via nasopharyngeal swab in the presence of suggestive clinical, radiological and laboratory findings. Since bronchoalveolar lavage liquid (BAL) collected during fibrobronchoscopy may increase test sensitivity compared to nasopharyngeal swabs, it was performed during the 2020 pandemic in clinically or radiologically suspected cases. Our aim was to determine whether clinical features, chest computed tomography (CT) findings or laboratory tests may predict patients testing positive for SARS-CoV-2 at BAL after a negative nasopharyngeal swab. We performed a retrospective cross-sectional study with multivariable analysis of suspected patients who were tested for SARS-CoV-2 at BAL after at least one negative nasopharyngeal swab. Univariable logistic regression for odds ratio and multivariate models was calculated to determine clinical, radiological and laboratory predictors. 32/198 (16%) patients had BAL positive for SARS-CoV-2, while 65/198 tested positive for other pathogens at BAL. Of the 32 patients positive for COVID, 4 had a coinfection at BAL, being thus positive both for COVID as well as for another pathogen while the remaining 105 patients were negative for COVID and other pathogens at BAL. COVID-19 patients had more often highly suggestive CT findings, higher number of involved lobes, more often ground glass opacity of more than 50% of lung parenchyma, and less frequently other radiologically suspected infections. At multivariate model, temperature also predicted BAL positivity. The procedure was well tolerated—with only one desaturation episode—while no healthcare worker was infected. In conclusion, when nasopharyngeal swabs are negative but there is clinical or imaging suspicion of COVID-19, BAL represents a complementary diagnostic tool, particularly in conjunction with suggestive/more extensive lung involvement at CT scan. The procedure did not carry increased risks for patients nor for operators, while allowing to free hospital resources, avoiding unnecessary isolations.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11739-021-02714-y.

Study of the Effects of Bronchoalveolar Lavage Liquid in the ARDS on the Functioning of the Neutrophil Polynuclear System

Study of the Effects of Bronchoalveolar Lavage Liquid in the ARDS on the Functioning of the Neutrophil Polynuclear System

42: Signal relay by CCR2 and formylpeptide receptor-2 (Fpr2) in the recruitment of monocyte-derived dendritic cells in allergic airway inflammation

Chemoattractant receptors regulate leukocyte accumulation at sites of inflammation. In allergic airway inflammation, although a chemokine receptor CCR2 was implicated in mediating monocyte-derived dendritic cell (DC) recruitment into the lung, we previously also discovered reduced accumulation of DCs in the inflamed lung in mice deficient in formylpeptide receptor Fpr2 (Fpr2−/−). We therefore investigated the role of Fpr2 in the trafficking of monocyte-derived DCs in allergic airway inflammation in cooperation with CCR2. We report that in allergic airway inflammation, CCR2 mediated the recruitment of monocyte-derived DCs to the perivascular region, and Fpr2 was required for further migration of the cells into bronchiolar area. We additionally found that the broncho-alveolar lavage liquid from mice with airway inflammation contained both the CCR2 ligand CCL2 and an Fpr2 agonist CRAMP. Furthermore, similar to Fpr2−/− mice, in the inflamed airway of CRAMP−/− mice, DC trafficking into the peribronchiolar areas was diminished. Our study demonstrates that the interaction of CCR2 and Fpr2 with their endogenous ligands sequentially mediates the trafficking of DCs within the inflamed lung.

Signal Relay by CC Chemokine Receptor 2 (CCR2) and Formylpeptide Receptor 2 (Fpr2) in the Recruitment of Monocyte-derived Dendritic Cells in Allergic Airway Inflammation

Chemoattractant receptors regulate leukocyte accumulation at sites of inflammation. In allergic airway inflammation, although a chemokine receptor CCR2 was implicated in mediating monocyte-derived dendritic cell (DC) recruitment into the lung, we previously also discovered reduced accumulation of DCs in the inflamed lung in mice deficient in formylpeptide receptor Fpr2 (Fpr2(-/-)). We therefore investigated the role of Fpr2 in the trafficking of monocyte-derived DCs in allergic airway inflammation in cooperation with CCR2. We report that in allergic airway inflammation, CCR2 mediated the recruitment of monocyte-derived DCs to the perivascular region, and Fpr2 was required for further migration of the cells into the bronchiolar area. We additionally found that the bronchoalveolar lavage liquid from mice with airway inflammation contained both the CCR2 ligand CCL2 and an Fpr2 agonist CRAMP. Furthermore, similar to Fpr2(-/-) mice, in the inflamed airway of CRAMP(-/-) mice, DC trafficking into the peribronchiolar areas was diminished. Our study demonstrates that the interaction of CCR2 and Fpr2 with their endogenous ligands sequentially mediates the trafficking of DCs within the inflamed lung.

Diagnosis and Treatment of Ventilator-Associated Pneumonia: Fiberoptic Bronchoscopy with Bronchoalveolar Lavage Is Essential

The management of patients suspected of having ventilator-associated pneumonia (VAP) requires a strategy for diagnosis and treatment that is designated to: (1) identify patients with true lung bacterial infection; (2) determine the pathogen(s) responsible for pneumonia; (3) permit early selection of appropriate antimicrobial therapy; and (4) avoid indiscriminate administration of antibiotics. The use of bronchoscopic techniques to obtain bronchoalveolar lavage (BAL) specimens from the affected area in the lung allows definition of a strategy superior to that based exclusively on clinical evaluation. When BAL is performed before introduction of new antibiotics, it enables physicians to identify patients who need immediate treatment and help to select initial antibiotic therapy (with the results of direct examination of BAL liquid) and to withhold, deescalate, and/or optimize treatment (when the results of quantitative cultures are available), in a manner that is safe and well tolerated by patients. This strategy, based on clinical and bacteriological evaluation, prevents resorting to broad-spectrum drug coverage in all patients who develop signs and symptoms suggestive of pneumonia, thus minimizing the emergence of resistant flora, and redirects the search for another infection site.

Detection of Aspergillus fumigatus hyphae by solid phase cytometry

A rapid method based on solid phase cytometry (SPC) for the detection of Aspergillus fumigatus hyphae is described. With an enzymatic ‘viability’ staining procedure, fungal hyphae can be detected non-specifically within the hour. By combining this procedure with an immunofluorescence labelling, a distinction between Aspergillus spp. and other clinically important fungi is possible, except for Penicillium spp. due to cross-reactivity. To differentiate both genera, microcolonies are generated by incubation at 45 °C prior to viability staining. The latter approach in conjunction with immunofluorescence labelling allows a quasi-specific detection of A. fumigatus hyphae and has shown its applicability to samples of bronchoalveolar lavage liquid (BAL).

Bronchoalveolar fluid is not a major hindrance to virus-mediated gene therapy in cystic fibrosis.

Successfully targeting the airway epithelium is essential for gene therapy of some pulmonary diseases. However, the airway epithelium is resistant to virus-mediated gene transfer with commonly used vectors. Vectors that interact with endogenously expressed receptors on the apical surface significantly increase gene transfer efficiency. However, other endogenous components involved in host immunity may hinder virus-mediated gene transfer. We tested the effect of bronchoalveolar lavage liquid (BAL) from patients with cystic fibrosis (CF), BAL from subjects without CF (non-CF BAL), Pseudomonas aeruginosa-derived proteins, and an array of inflammatory proteins on gene transfer mediated by adeno-associated virus type 5 (AAV5) and adenovirus targeted to an apically expressed glycosylphosphatidylinositol-modified coxsackie-adenovirus receptor. We found that neither CF BAL nor its components had a significant effect on gene transfer to human airway epithelium by these vectors. Non-CF BAL significantly impaired adenovirus-mediated gene transfer. Removal of immunoglobulins in non-CF BAL restored gene transfer efficiency. As virus vectors are improved and mechanisms of humoral immunity are elucidated, barriers to successful gene therapy found in the complex environment of the human lung can be circumvented.

The clinical significance of detection of telomerase in bronchoalveolar lavage liquid in patients with lung cancer

To investigate the diagnostic significance of detection of telomerase activity of bronchoalveolar lavage liquid (BALF) in primary lung cancer. BALF of 63 patients with lung cancer and 31 patients with non-cancerous pulmonary disease was collected, and telomerase activity was detected with silver-stained TRAP. Brush cytology and BALF cytology were carried out simultaneously. The positive rate of telomerase was 76.2% (48/63) in lung cancer group, which was higher than 6.5% (2/31) in control group (Chi-square=40.6, P < 0.01). The positive rate was also higher than that of brush cytology (58.7%, 37/63) (Chi-square =3.6, P > 0.05), and higher than that of BALF cytology (14.3%, 9/63) (Chi-square=46.3, P < 0.01). In central type lung cancer group, the positive rate of telomerase was 71.4% (35/49), and higher than that of BALF cytology (12.2%, 6/49) (Chi-square= 35.3 , P < 0.01), but had no significant difference compared to that of brush cytology (61.2%, 30/49) (Chi-square=1.1, P > 0.05). In peripheral-type lung cancer group, the positive rate of telomerase in BALF was 92.9% (13/14), and higher than that of brush cytology (50.0%, 7/14) and that of BALF cytology (21.4%, 3/14). The telomerase activity could be detected in the BALF of the primary lung cancer. Hence, detection of telomerase in the BALF of patients may be helpful to diagnose lung cancer.

Parathyroid hormone-related protein and lung injury after pulmonary thromboendarterectomy

Parathyroid hormone-related protein (PTHrP) is an autocrine growth and differentiation factor for alveolar type II epithelial cells. Type II cells secrete pulmonary surfactant and are pluripotent cells with a role in alveolar epithelial repair after lung injury. The goals of this study were to investigate whether the levels of PTHrP in bronchoalveolar lavage liquid (BAL) varied between patients who did and did not develop lung injury after pulmonary thromboendarterectomy (PTE). BAL was performed in 48 patients undergoing PTE for unresolved pulmonary emboli. Samples were obtained following induction of anesthesia, following separation from cardiopulmonary bypass, and 48 h postoperatively. PTHrP was measured by radioimmunoassay. Lung injury was diagnosed in 23 patients on the basis of hypoxemia (PaO 2/FIO 2<300) and the presence of lung infiltrates in the absence of infection or atelectasis. Patients with lung injury had significantly lower preoperative BAL levels of PTHrP, 21 (21–30) pg/ml (median, interquartile gap), compared to patients without lung injury, 34 (21–41) pg/ml ( P<0.05). Preoperative BAL PTHrP levels <32 pg/ml predicted lung injury with a positive predictive value of 60% and negative predictive value of 82%. The odds of developing lung injury for patients with preoperative PTHrP levels below this cutpoint were 6 times the odds for patients with higher levels.

Reduced Priming Capacity of Bronchoalveolar Lavage Liquid on Polymorphonuclear Leucocytes after Nedocromil Therapy in Asthmatic Children

Reduced Priming Capacity of Bronchoalveolar Lavage Liquid on Polymorphonuclear Leucocytes after Nedocromil Therapy in Asthmatic Children

Baseline Lung Function and Inflammatory Indices in Guinea Pigs: Effects of Growth, Repeated Lavage, and Orotracheal Intubation

We examined the relationships between baseline lung function, weight, and indices of inflammation in bronchoalveolar lavage (BAL) liquid in unsensitized, anesthetized guinea pigs (GPs) and evaluated a model for performing orotracheal intubation and BAL without having to sacrifice the animal. Thirty-six GPs were anesthetized and orotracheally intubated. Lung resistance (RL) and elastance (EL) were measured. BAL was then performed with sterile saline, and the animal permitted to cover. White blood cells and differentials, total protein (TP), histamine, prostaglandins (PGs) D2, F2a, E2, leukotrienes (LTs) B4, and C4/D4/E4 were measured in the BAL liquid as indices of inflammation. Body weight (and by inference, age) directly correlated with BAL concentrations at TP and PGD2 and inversely correlated with LTC4/D4/E4 and % eosinophils. Significant correlations were found between PGD2 vs. TP (r = 0.54, p less than .001), histamine vs. % eosinophils (r = 0.45, p = 0.03), and % macrophages vs. % neutrophils (r = -0.76, p less than .001). RL and EL did not correlate with BAL measurements of cells or mediators. A second group of 9 animals was lavaged, permitted to recover, and relavaged 2 weeks later, with no significant changes noted in lung mechanics, BAL cell profiles, or mediators between study days. These data demonstrate that some baseline BAL inflammatory indices in the GP correlate well with body weight and with each other and that baseline BAL measurements of inflammatory mediators may vary with size or age of the animal, an important consideration in studies using the GP for BAL measurements of inflammatory mediators. The data further document the reproducibility and feasibility of reintubating and lavaging the same animal over a period separated by 2 weeks without having to sacrifice the animal.

Alterations of the Endoalveolar Surfactant after Surgery with Extracorporeal Circulation

In 10 patients who required extracorporeal circulation (ECC) during surgery, we studied the damage induced by surgery to the pulmonary surfactant and the effectiveness of ambroxol in preventing changes in the phospholipid pool. There were 5 control patients and 5 patients who were given 1 g/day of ambroxol on the 4 days prior to and the 4 days after surgery. To follow changes in phospholipid concentrations, bronchoalveolar lavage (BAL) was performed before surgery and 24 h and 8 days after ECC. Phospholipids were assayed in the BAL liquid by two-dimensional thin-layer chromatography. There were marked decreases in total phosphorus and quantitative alterations of individual phospholipid species in the surfactant of the control group, but not in the patients treated with ambroxol.