Mucosal inflammation in idiopathic bronchiectasis: cellular and molecular mechanisms

Is there a role for lung or bronchial biopsies for the diagnosis of mycobacterial pulmonary disease in patients with bronchiectasis?

Background

Workup of bronchiectasis patients mandates microbiological characterization often being sought via Bronchoscopy. However, whether to perform bronchial or lung biopsies, is unknown, especially for the diagnosis of NTM pulmonary disease. We aimed to assess the current practice and yield of the different bronchoscopic procedures in this setting.

Methods

Data from an adult cohort with bronchiectasis referred for bronchoscopy for microbiologic sampling was reviewed, including demographics, etiology, imaging and results of the different bronchoscopic procedures performed.

Results

127 subjects were analyzed (mean age 61, 56% female). BAL culture was positive in 44%. Frequent pathogens were Hemophilus Influenza (20%), pseudomonas aeruginosa (8%) and Staphylococcus aureus (7%). NTM and tuberculosis were found in 6% and 1.5% respectively. BAL cytology was sent in 125 procedures, EBB was performed in 51 patients (40%) and TBLB in 38 patients (30%). BAL cytology and both EBB and TBB (including tissue cultures) had no benefit over BAL with respect to microbiological diagnosis, including identification of mycobacterial disease.

Conclusions

In adult subjects with Non-CF bronchiectasis requiring bronchoscopy for microbiological characterization, BAL cytology and lung tissue biopsies were frequently performed but were of minimal additional benefit over BAL culture (including for mycobacterial pulmonary disease), and are most likely futile.

Cardiovascular outcomes following hospitalisation for exacerbation of bronchiectasis: a territory-wide study

BACKGROUND

Although bronchiectasis is reported to be associated with cardiovascular disease, evidence for an association with cardiovascular events (CVEs) is lacking.

METHODS

A territory-wide retrospective cohort study was conducted in Hong Kong involving all patients who had bronchiectasis diagnosed in public hospitals and clinics between 1 January 1993 and 31 December 2017 were included. Patients were allocated to be exacerbator or non-exacerbator group based on hospitalzied bronchiecsis history and CVEs over the next 5 years determined. Propensity score matching was used to balance baseline characteristics.

RESULTS

10 714 bronchiectasis patients (mean age 69.6±14.4 years, 38.9% men), including 1230 in exacerbator group and 9484 in non-exacerbator group, were analysed. At 5 years, 113 (9.2%) subjects in the exacerbator group and 87 (7.1%) in the non-exacerbator group developed composite CVEs. After adjustment for age, sex, smoking and risk factors for cardiovascular disease, bronchiectasis exacerbation was associated with increased risks for acute myocardial infarction (AMI), congestive heart failure (CHF) and CVE compared with those in the non-exacerbator group with adjusted HR of 1.602 (95% CI 1.006-2.552, p value=0.047), 1.371 (95% CI 1.016-1.851, p value=0.039) and 1.238 (95% CI 1.001-1.532, p=0.049) in the whole cohort. Findings were similar for the propensity score-matched cohort for AMI and CVE.

CONCLUSION

Patients who were hospitalised for exacerbation of bronchiectasis were at significantly increased risk of AMI, CHF and CVE over a 5-year follow-up period.

Bronchiectasis not due to cystic fibrosis

Bronchiectasis is a clinical-radiological condition composed of irreversible bronchial dilation due to inflammation and infection of the airways, which causes respiratory symptoms, usually productive cough and infectious exacerbations. Bronchiectasis can have multiple causes, both pulmonary and extrapulmonary, and its clinical presentation is very heterogenous. Its prevalence is unknown, although up to 35-50% of severe COPD and 25% of severe asthma present them, so their underdiagnosis is evident. Chronic bacterial bronchial infection is common, and Pseudomonas aeruginosa is the pathogen that has been found to imply a worse prognosis. Treatment of bronchiectasis has three fundamental characteristics: it must be multidisciplinary (involvement of several specialties), pyramidal (from primary care to the most specialized units) and multidimensional (management of all aspects that make up the disease).

Chronic obstructive pulmonary disease and the airway microbiome: A review for clinicians

Chronic obstructive pulmonary disease (COPD) is a complex heterogeneous disease characterized by progressive airflow limitation and chronic inflammation. The progressive development and long-term repeated acute exacerbation of COPD make many patients still unable to control the deterioration of the disease after active treatment, and even eventually lead to death. An increasing number of studies have shown that the occurrence and development of COPD are closely related to the composition and changes of airway microbiome. This article reviews the interaction between COPD and airway microbiome, the potential mechanisms of interaction, and the treatment methods related to microbiome. We elaborated the internal correlation between airway microbiome and different stages of COPD, inflammatory endotypes, glucocorticoid and antibiotic treatment, analyze the pathophysiological mechanisms such as the "vicious cycle" hypothesis, abnormal inflammation-immune response of the host and the "natural selection" of COPD to airway microbiome, introduce the treatment of COPD related to microbiome and emphasize the predictive value of airway microbiome for the progression, exacerbation and prognosis of COPD, as well as the guiding role for clinical management of patients, in order to provide a new perspective for exploring the pathogenesis of COPD, and also provide clues and guidance for finding new treatment targets.

High-sensitivity C-reactive protein level in stable-state bronchiectasis predicts exacerbation risk

BACKGROUND

Elevation of systemic inflammatory markers were found to correlate with increased disease extent, reduced lung function and higher risk of future severe exacerbations in patients with bronchiectasis. Although a significant correlation of circulating hs-CRP levels with HRCT scores and resting oxygen saturation in patients with stable-state non-cystic fibrosis (CF) bronchiectasis was suggested, there is little data on the relationship between hs-CRP and the prognosis of bronchiectasis and a lack of data on the role of hs-CRP in predicting bronchiectasis exacerbation.

METHODS

A prospective study was conducted on Chinese patients with non- CF bronchiectasis from 1st October to 31st December 2021. Baseline serum hs-CRP were obtained at stable-state. The follow-up period lasted for one year. Co-primary endpoints were the development of any bronchiectasis exacerbation and hospitalized bronchiectasis exacerbation.

RESULTS

Totally 123 patients were included. Higher hs-CRP was associated with increased risk to develop any bronchiectasis exacerbation, adjusted odds ratio (aOR) of 2.254 (95% CI = 1.040-4.885, p = 0.039), and borderline significantly increased hospitalized bronchiectasis exacerbation with aOR of 1.985 (95% CI = 0.922-4.277, p = 0.080).

CONCLUSION

Baseline serum hs-CRP level at stable-state can predict risk of bronchiectasis exacerbation, which is reflecting chronic low-grade inflammation in bronchiectasis.

Inflammatory Molecular Endotypes in Bronchiectasis: A European Multicenter Cohort Study

Rationale: Although inflammation and infection are key disease drivers in bronchiectasis, few studies have integrated host inflammatory and microbiome data to guide precision medicine. Objectives: To identify clusters among patients with bronchiectasis on the basis of inflammatory markers and to assess the association between inflammatory endotypes, microbiome characteristics, and exacerbation risk. Methods: Patients with stable bronchiectasis were enrolled at three European centers, and cluster analysis was used to stratify the patients according to the levels of 33 sputum and serum inflammatory markers. Clusters were compared in terms of microbiome composition (16S ribosomal RNA sequencing) and exacerbation risk over a 12-month follow-up. Measurements and Main Results: A total of 199 patients were enrolled (109 [54.8%] female; median age, 69 yr). Four clusters of patients were defined according to their inflammatory profiles: cluster 1, milder neutrophilic inflammation; cluster 2, mixed-neutrophilic and type 2; cluster 3, most severe neutrophilic; and cluster 4, mixed-epithelial and type 2. Lower microbiome diversity was associated with more severe inflammatory clusters (P < 0.001), and β-diversity analysis demonstrated distinct microbiome profiles associated with each inflammatory cluster (P = 0.001). Proteobacteria and Pseudomonas at phylum and genus levels, respectively, were more enriched in clusters 2 and 3 than in clusters 1 and 4. Furthermore, patients in cluster 2 (rate ratio [RR], 1.49; 95% confidence interval [CI], 1.16-1.92) and cluster 3 (RR, 1.61; 95% CI, 1.12-2.32) were at higher risk of exacerbation over a 12-month follow-up compared with cluster 1, even after adjustment for prior exacerbation history. Conclusions: Bronchiectasis inflammatory endotypes are associated with distinct microbiome profiles and future exacerbation risk.

Autoimmunity in people with cystic fibrosis

Cystic fibrosis (CF) clinicians may see patients who have difficult-to-manage symptoms that do not have a clear CF-related etiology, such as unusual gastrointestinal (GI) complaints, vasculitis, or arthritis. Alterations in immunity, inflammation and intraluminal dysbiosis create a milieu that may lead to autoimmunity, and the CF transmembrane regulator protein may have a direct role as well. While autoantibodies and other autoimmune markers may develop, these may or may not lead to organ involvement, therefore they are helpful but not sufficient to establish an autoimmune diagnosis. Autoimmune involvement of the GI tract is the best-established association. Next steps to understand autoimmunity in CF should include a more in-depth assessment of the community perspective on its impact. In addition, bringing together specialists in various fields including, but not limited to, pulmonology, gastroenterology, immunology, and rheumatology, would lead to cross-dissemination and help define the path forward in basic science and clinical practice.

Bronchiectasis-COPD Overlap Syndrome: Role of Peripheral Eosinophil Count and Inhaled Corticosteroid Treatment

Both chronic obstructive pulmonary disease and bronchiectasis are highly prevalent diseases. In both cases, inhaled corticosteroids (ICs) are associated with a decrease in exacerbations in patients with a high peripheral blood eosinophil count (BEC), but it is still not known what occurs in bronchiectasis-COPD overlap syndrome (BCOS). The present study aimed to assess the effect of ICs on various outcomes in patients with BCOS, according to BEC values. We undertook a post-hoc analysis of a cohort of 201 GOLD II-IV COPD patients with a long-term follow-up (median 74 [IQR: 40-106] months). All participants underwent computerized tomography and 115 (57.2%) had confirmed BCOS. A standardized clinical protocol was followed and two sputum samples were collected at each medical visit (every 3-6 months), whenever possible. During follow-up, there were 68 deaths (59.1%), and the mean rate of exacerbations and hospitalizations per year was 1.42 (1.2) and 0.57 (0.83), respectively. A total of 44.3% of the patients presented at least one pneumonic episode per year. The mean value of eosinophils was 402 (112) eosinophils/µL, with 27 (23.5%), 63 (54.8%), and 25 patients (21.7%) presenting, respectively, less than 100, 101-300, and more than 300 eosinophils/µL. A total of 84 patients (73.1%) took ICs. The higher the BEC, the higher the annual rate of exacerbations and hospitalizations. Patients with less than 100 eosinophils/µL presented more infectious events (incident exacerbations, pneumonic episodes, and chronic bronchial infection via pathogenic bacteria). Only those patients with eosinophilia (>300 eosinophils/µL) treated with ICs decreased the number (1.77 (1.2) vs. 1.08 (0.6), p < 0.001) and the severity (0.67 (0.8) vs. 0.35 (0.5), p = 0.011) of exacerbations, without any changes in the other infectious outcomes or mortality. In conclusion, ICs treatment in patients with BCOS with increased BEC decreased the number and severity of incident exacerbations without any negative influence on other infectious outcomes (incidence of pneumonia or chronic bronchial infection).

Chronic airway epithelial hypoxia exacerbates injury in muco-obstructive lung disease through mucus hyperconcentration

Unlike solid organs, human airway epithelia derive their oxygen from inspired air rather than the vasculature. Many pulmonary diseases are associated with intraluminal airway obstruction caused by aspirated foreign bodies, virus infection, tumors, or mucus plugs intrinsic to airway disease, including cystic fibrosis (CF). Consistent with requirements for luminal O2, airway epithelia surrounding mucus plugs in chronic obstructive pulmonary disease (COPD) lungs are hypoxic. Despite these observations, the effects of chronic hypoxia (CH) on airway epithelial host defense functions relevant to pulmonary disease have not been investigated. Molecular characterization of resected human lungs from individuals with a spectrum of muco-obstructive lung diseases (MOLDs) or COVID-19 identified molecular features of chronic hypoxia, including increased EGLN3 expression, in epithelia lining mucus-obstructed airways. In vitro experiments using cultured chronically hypoxic airway epithelia revealed conversion to a glycolytic metabolic state with maintenance of cellular architecture. Chronically hypoxic airway epithelia unexpectedly exhibited increased MUC5B mucin production and increased transepithelial Na+ and fluid absorption mediated by HIF1α/HIF2α-dependent up-regulation of β and γENaC (epithelial Na+ channel) subunit expression. The combination of increased Na+ absorption and MUC5B production generated hyperconcentrated mucus predicted to perpetuate obstruction. Single-cell and bulk RNA sequencing analyses of chronically hypoxic cultured airway epithelia revealed transcriptional changes involved in airway wall remodeling, destruction, and angiogenesis. These results were confirmed by RNA-in situ hybridization studies of lungs from individuals with MOLD. Our data suggest that chronic airway epithelial hypoxia may be central to the pathogenesis of persistent mucus accumulation in MOLDs and associated airway wall damage.

Down-expression of Foxj1 on airway epithelium with impaired cilia architecture in non-cystic fibrosis bronchiectasis implies disease severity

INTRODUCTION

The pathogenesis of non-cystic fibrosis bronchiectasis has not been clearly clarified. This study aimed to investigate the expression of ciliary regulating protein forkhead box protein j1 (Foxj1) on airway epithelium in non-cystic fibrosis bronchiectasis and its association with airway cilia structure disorder and disease severity.

METHODS

Lung tissue sections excised from 47 patients with non-cystic fibrosis bronchiectasis were included between January 2018 and June 2021. Specimens from 26 subjects who underwent a lobectomy due to lung nodule were chosen as controls. Clinical information was collected, and pathologic analysis was performed to assess the epithelial structure and expression of ciliary regulating Foxj1.

RESULTS

Of the 47 patients with non-cystic fibrosis bronchiectasis, 25 were considered as mild, 12 were moderate whereas the remaining 10 cases were severe according to the bronchiectasis severity index score evaluation. Epithelial hyperplasia, hyperplasia of goblet cells and inflammatory cell infiltration were observed in non-cystic fibrosis bronchiectasis, compared with control subjects. Cilia length in non-cystic fibrosis bronchiectasis patients were shorter than that in the control group, (5.34 ± 0.89) μm versus (7.34 ± 0.71) μm, respectively (P = 0.002). The expression of Foxj1 was (2.69 ± 1.09) × 10⁶ in non-cystic fibrosis bronchiectasis, compared with (6.67 ± 1.15) × 10⁶ in the control group (P = 0.001). Moreover, patients with lower expression of Foxj1 showed shorter airway cilia and worse in disease severity.

CONCLUSION

Foxj1 declined in the airway epithelium of patients with non-cystic fibrosis bronchiectasis, positively correlated to cilia length and might imply worse disease severity.

Sleep-Disordered Breathing and Chronic Respiratory Infections: A Narrative Review in Adult and Pediatric Population

Sleep-disordered breathing (SDB) comprises different diseases characterized by abnormal respiratory patterns during sleep including obstructive sleep apnea. SDB prevalence and impact in patients with chronic respiratory infections have been only marginally studied. The purpose of this narrative review is to report the prevalence and impact of SDB in chronic respiratory infections, including cystic fibrosis (CF), bronchiectasis and mycobacterial infections, and explore the possible pathophysiological mechanisms. Common pathophysiological mechanisms, underlying SDB onset in all chronic respiratory infections, include inflammation, which plays a central role, chronic nocturnal cough and pain, excessive production of mucous plugs, presence of obstructive and/or restrictive ventilatory impairment, upper airways involvement, and comorbidities, such as alteration of nutritional status. SDB may affect about 50% of patients with bronchiectasis. The severity of the disease, e.g., patients colonized with P. aeruginosa and frequent exacerbators, as well as comorbidities, such as chronic obstructive pulmonary disease and primary ciliary dyskinesia, may impact SDB onset. SDB may also frequently complicate the clinical course of both children and adults with CF, impacting the quality of life and disease prognosis, suggesting that their routine assessment should be incorporated into the clinical evaluation of patients from the first stages of the disease regardless of suggestive symptoms, in order to avoid late diagnosis. Finally, although the prevalence of SDB in patients with mycobacterial infections is uncertain, extrapulmonary manifestations, particularly nasopharyngeal locations, and concomitant symptoms, such as body pain and depression, may act as atypical predisposing factors for their development.

Adiponectin Increase in Patients Affected by Chronic Obstructive Pulmonary Disease with Overlap of Bronchiectasis

Chronic obstructive pulmonary disease (COPD) is characterized by respiratory symptoms and non-reversible airflow limitation with recurrent episodes of acute exacerbations. The concurrent presence of bronchiectasis in patients with COPD is associated with reduced respiratory function as well as increased exacerbation risk. Adiponectin is a promising biomarker in COPD, as greater high molecular weight (HMW) oligomer levels have been observed among COPD patients. Here, we investigate adiponectin levels in two groups of COPD patients characterized by the presence or absence of bronchiectasis (BCO), comparing both groups to healthy controls. We evaluated serum adiponectin levels in COPD patients, those with BCO, and healthy subjects and characterized the pattern of circulating adiponectin oligomers. We found that forced volume capacity % (FVC%) and forced expiratory volume % (FEV1%) were lower for BCO patients than for COPD patients. COPD patients had higher levels of adiponectin and its HMW oligomers than healthy controls. Interestingly, BCO patients had higher levels of adiponectin than COPD patients. We showed that expression levels of IL-2, -4, and -8, IFN-γ, and GM-CSF were significantly higher in BCO patients than in healthy controls. Conversely, IL-10 expression levels were lower in BCO patients. Our data suggest that the increased levels of adiponectin detected in the cohort of BCO patients compared to those in COPD patients without bronchiectasis might be determined by their worse airway inflammatory state. This hypothesis suggests that adiponectin could be considered as a biomarker to recognize advanced COPD patients with bronchiectasis.

Simultaneous evaluation of the fractional exhaled nitric oxide and blood eosinophil count of T2-high endotype in patients with non-cystic fibrosis bronchiectasis

OBJECTIVE

Recently, a type 2 inflammation (T2) high endotype in bronchiectasis was identified. The fraction of exhaled nitric oxide (FeNO) and blood eosinophil count (BEC) are recognized as representative biomarkers of T2 inflammation. Herein, we investigate the clinical characteristics of T2-high endotype in non-cystic fibrosis bronchiectasis patients classified by FeNO and BEC.

METHODS

This retrospective study included 164 bronchiectasis patients treated in the First Affiliated Hospital of Sun Yat-sen University from December 2017 to July 2022. Clinical characteristics were analyzed after classifying patients into four groups according to T2 inflammation biomarkers (FeNO ≥25 ppb; BEC ≥200/µL).

RESULTS

Among the 164 bronchiectasis patients, 35.3% (58/164) presented with high FeNO, 30.5% (50/164) presented with high BEC, and 10.4% (17/164) had high FeNO and BEC. Patients with high FeNO and low BEC presented with better lung function, fewer affected lobes, and lower dyspnea prevalence compared with the three other groups. Moreover, decreased FeNO, instead of decreased BEC, is revealed to be an independent predictor for disease severity and airflow obstruction in bronchiectasis.

CONCLUSIONS

Simultaneous evaluation of FeNO and BEC proposed different endotypes of bronchiectasis established that patients with low BEC and high FeNO had better lung function, fewer affected lobes, lower dyspnea prevalence, and less disease severity. This result will contribute to a more comprehensive assessment of the disease severity and lead to more precise treatment of T2 inflammation in bronchiectasis patients.

Inhaled Corticosteroids in Adults with Non-cystic Fibrosis Bronchiectasis: From Bench to Bedside. A Narrative Review

Due to their potent anti-inflammatory capacity (particularly in predominantly eosinophilic inflammation) and immunosuppressive properties, inhaled corticosteroids (ICSs) are widely used in asthmatic patients and also in individuals with chronic obstructive pulmonary disease (COPD) who suffer multiple exacerbations or have peripheral eosinophilia. However, there is little evidence for their use in non-cystic fibrosis bronchiectasis (hereafter, bronchiectasis). According to data extracted from large databases of bronchiectasis in adults, ICSs are used in more than 50% of patients without any scientific evidence to justify their efficacy and contrary to the recommendations of international guidelines on bronchiectasis that generally advise against their use. Indeed, bronchiectasis is a disease with predominantly neutrophilic inflammation and a high likelihood of chronic bacterial bronchial infection. Furthermore, it is known that due to their immunosuppressive properties, ICSs can induce an increase in bacterial infections. This manuscript aims to review the basic properties of ICSs, how they impact bronchiectasis in adults, the current position of international guidelines on this treatment, and the current indications and future challenges related to ICS use in bronchiectasis.

The efficacy of azithromycin to prevent exacerbation of non-cystic fibrosis bronchiectasis: a meta-analysis of randomized controlled studies

Introduction

The efficacy of azithromycin to prevent exacerbation for non-cystic fibrosis bronchiectasis remains controversial. We conduct this meta-analysis to explore the influence of azithromycin versus placebo for the treatment of non-cystic fibrosis bronchiectasis.

Methods

We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through July 2019 for randomized controlled trials (RCTs) assessing the efficacy of azithromycin versus placebo for non-cystic fibrosis bronchiectasis. This meta-analysis was performed using the random-effect model.

Results

Four RCTs were included in the meta-analysis. Overall, compared with control group for non-cystic-fibrosis bronchiectasis, azithromycin treatment was associated with improved free of exacerbation (odd ratios [OR] = 3.66; 95% confidence interval [CI] = 1.69–7.93; P = 0.001), reduced pulmonary exacerbations (OR = 0.27; 95% CI 0.13–0.59; P = 0.001) and number of pulmonary exacerbations (standard mean difference [SMD] =  − 0.87; 95% CI − 1.21 to − 0.54; P < 0.00001), but demonstrate no obvious impact on forced expiratory volume in 1 s (FEV1), score on St George’s respiratory questionnaire, nausea or vomiting, adverse events.

Conclusions

Azithromycin is effective to prevent exacerbation of non-cystic fibrosis bronchiectasis.

Peripheral Neutrophil-to-Lymphocyte Ratio in Bronchiectasis: A Marker of Disease Severity

Most patients with bronchiectasis have a predominantly neutrophilic inflammatory profile, although other cells such as lymphocytes (as controllers of bronchial inflammation) and eosinophils also play a significant pathophysiological role. Easy-to-interpret blood biomarkers with a discriminative capacity for severity or prognosis are needed. The objective of this study was to assess whether the peripheral neutrophil-to-lymphocyte ratio (NLR) is associated with different outcomes of severity in bronchiectasis. A total of 1369 patients with bronchiectasis from the Spanish Registry of Bronchiectasis were included. To compare groups, the sample was divided into increasing quartiles of NLR ratio. Correlations between quantitative variables were established using Pearson's P test. A simple linear regression (with the value of exacerbations as a quantitative variable) was used to determine the independent relationship between the number and severity of exacerbations and the NLR ratio. The area under the curve (AUC)-ROC was used to determine the predictive capacity of the NLR for severe bronchiectasis, according to the different multidimensional scores. Mean age: 69 (15) years (66.3% of women). The mean NLR was 2.92 (2.03). A higher NLR was associated with more severe bronchiectasis (with an especially significant discriminative power for severe forms) according to the commonly used scores (FACED, E-FACED and BSI), as well as with poorer quality of life (SGRQ), more comorbidities (Charlson index), infection by pathogenic microorganisms, and greater application of treatment. Furthermore, the NLR correlated better with severity scores than other parameters of systemic inflammation. Finally, it was an independent predictor of the incident number and severity of exacerbations. In conclusion, the NLR is an inexpensive and easy-to-measure marker of systemic inflammation for determining severity and predicting exacerbations (especially the most severe) in patients with bronchiectasis.

Neisseria species as pathobionts in bronchiectasis

Neisseria species are frequently identified in the bronchiectasis microbiome, but they are regarded as respiratory commensals. Using a combination of human cohorts, next-generation sequencing, systems biology, and animal models, we show that bronchiectasis bacteriomes defined by the presence of Neisseria spp. associate with poor clinical outcomes, including exacerbations. Neisseria subflava cultivated from bronchiectasis patients promotes the loss of epithelial integrity and inflammation in primary epithelial cells. In vivo animal models of Neisseria subflava infection and metabolipidome analysis highlight immunoinflammatory functional gene clusters and provide evidence for pulmonary inflammation. The murine metabolipidomic data were validated with human Neisseria-dominant bronchiectasis samples and compared with disease in which Pseudomonas-, an established bronchiectasis pathogen, is dominant. Metagenomic surveillance of Neisseria across various respiratory disorders reveals broader importance, and the assessment of the home environment in bronchiectasis implies potential environmental sources of exposure. Thus, we identify Neisseria species as pathobionts in bronchiectasis, allowing for improved risk stratification in this high-risk group.

Practical tips in bronchiectasis for Primary Care

Bronchiectasis is the third most common chronic inflammatory airway disease, after chronic obstructive pulmonary disease (COPD) and asthma with a prevalence clearly underestimated probably because of its clinical similitudes with other chronic airway diseases. Bronchiectasis can be caused by a dozen of pulmonary and extra-pulmonary diseases and a variable number and severity of exacerbations can appear throughout its natural history, usually with an infectious profile. The dilation of the airway and the inflammation/infection is their radiological and pathophysiological hallmarks. Primary Care should play an important play in many aspects of the bronchiectasis assessment. In this article, we will try to offer a series of important concepts and practical tips on some key aspects of the diagnosis and management of bronchiectasis in Primary Care: clinical suspicion, diagnostic methods, severity assessment, overlap with asthma and COPD and microbiological and therapeutic aspects.

Acute and long-term management of severe bronchiectasis with high flow nasal therapy: A case report

Bronchiectasis (BE) is a long-term, chronic lung condition featured by widened and scarred airways. These can alter the physiological mucociliary clearance, making it difficult to clear mucus and microorganisms, leading to frequent exacerbations. High flow nasal therapy (HFNT) is a noninvasive respiratory support that delivers heated and humidified gas eventually enriched with oxygen, through a nasal cannula.  Humidification is crucial for adequate airways mucociliary clearance, improving ciliary function and consequently reducing airways inflammation and recurrent infections. HFNT has been mostly used in patients with acute hypoxemic respiratory failure and in selected patients with chronic respiratory failure due to COPD. Still, evidence about its use in acute and long-term home setting in patients with clinically relevant BE are lacking. We report a case of severe widespread BE, already on top medical therapy and pulmonary rehabilitation, still suffering from difficult mucus expectoration and recurrent exacerbations, who has been additionally treated with HFNT, both in hospital and domiciliary, reporting significant improvements on relevant clinical and patient-centered outcomes. Thus, HFNT may confer additional benefits as an add-on treatment of patients with severe BE and respiratory failure.

Morphological features of bronchiectasis in patients with non-tuberculous mycobacteriosis and interstitial pneumonia

Objective

To compare the morphological features of bronchiectasis between patients with different underlying diseases, we performed quantitative analysis of high-resolution computed tomography (HRCT) images of 14 patients with non-tuberculous mycobacteriosis (NTM) and 13 with idiopathic pulmonary fibrosis (IPF). A 3D image of the bronchial structure was made from HRCT data. Bronchiectasis was defined as abnormal dilatation of the bronchi with the diameter greater than that of the accompanying pulmonary artery. We measured the inner and outer diameters, wall area as %total airway cross sectional area (WA%), and wall thickness to airway diameter ratio (T/D) of the 4-8th generations of bronchi.

Results

In patients with IPF, the inner and outer diameters linearly decreased toward the distal bronchi. In contrast, the inner and outer diameters of NTM fluctuated. The coefficient of variation of the outer diameters of the 6-7th generations of bronchi was larger in the NTM patients than in those with IPF, whereas no significant difference was observed in the coefficient of variation of the inner diameters between the groups. In IPF patients, WA% and T/D varied between the generation of bronchi, but the coefficient of variation of WA% and T/D was relatively small in those with NTM.

Rationale and Clinical Use of Bronchodilators in Adults with Bronchiectasis

Currently, there is much controversy surrounding the therapeutic approach to pulmonary function abnormalities in patients with bronchiectasis and, consequently, whether and when to use bronchodilators in these patients. National and international guidelines on the treatment of bronchiectasis in adults do not recommend the routine use of bronchodilators because there is no evidence that a significant response to a bronchodilator or the presence or hyperresponsiveness of the airway are good predictors of future effective clinical response. However, some guidelines recommend them in the presence of airway obstruction and/or special conditions, which vary according to the guideline in question, although there are no recommendations on optimal dosing and bronchodilator treatment combined with or without inhaled corticosteroids. Nonetheless, in contrast with guideline recommendations, bronchodilators are overused in real-world patients with bronchiectasis even in the absence of airway obstruction, as demonstrated by analysis of national and international registries. This overuse can be explained by the awareness of the existence of a solid pharmacological rationale that supports the use of bronchodilators in the presence of chronic airway obstruction independent of its aetiology. We performed a systematic review of the literature and were able to verify that there are no randomised controlled trials (apart from a small study with methodological limitations and a very recent trial involving a not-very-large number of patients), or any long-term observational studies on the short- or long-term effect of bronchodilators in patients with bronchiectasis. Therefore, we believe that it is essential and even urgent to evaluate the effects of bronchodilators in these patients with appropriately designed studies.

Phenotypic Clustering in Non-Cystic Fibrosis Bronchiectasis Patients: The Role of Eosinophils in Disease Severity

Whether high blood eosinophil counts may define a better phenotype in bronchiectasis patients, as shown in chronic obstructive pulmonary disease (COPD), remains to be investigated. Differential phenotypic characteristics according to eosinophil counts were assessed using a biostatistical approach in a large cohort study from the Spanish Online Bronchiectasis Registry (RIBRON). The 906 patients who met the inclusion criteria were clustered into two groups on the basis of their eosinophil levels. The potential differences according to the bronchiectasis severity index (BSI) score between two groups (Mann–Whitney U test and eosinophil count threshold: 100 cells/µL) showed the most balanced cluster sizes: above-threshold and below-threshold groups. Patients above the threshold exhibited significantly better clinical outcomes, lung function, and nutritional status, while showing lower systemic inflammation levels. The proportion of patients with mild disease was higher in the above-threshold group, while the below-threshold patients were more severe. Two distinct clinical phenotypes of stable patients with non-cystic fibrosis (CF) bronchiectasis of a wide range of disease severity were established on the basis of blood eosinophil counts using a biostatistical approach. Patients classified within the above-threshold cluster were those exhibiting a mild disease, significantly better clinical outcomes, lung function, and nutritional status while showing lower systemic inflammatory levels. These results will contribute to better characterizing bronchiectasis patients into phenotypic profiles with their clinical implications.

Neutrophil Elastase and Chronic Lung Disease

Neutrophil elastase (NE) is a major inflammatory protease released by neutrophils and is present in the airways of patients with cystic fibrosis (CF), chronic obstructive pulmonary disease, non-CF bronchiectasis, and bronchopulmonary dysplasia. Although NE facilitates leukocyte transmigration to the site of infection and is required for clearance of Gram-negative bacteria, it also activates inflammation when released into the airway milieu in chronic inflammatory airway diseases. NE exposure induces airway remodeling with increased mucin expression and secretion and impaired ciliary motility. NE interrupts epithelial repair by promoting cellular apoptosis and senescence and it activates inflammation directly by increasing cytokine expression and release, and indirectly by triggering extracellular trap release and exosome release, which magnify protease activity and inflammation in the airway. NE inhibits innate immune function by digesting opsonins and opsonin receptors, degrading innate immune proteins such as lactoferrin, and inhibiting macrophage phagocytosis. Importantly, NE-directed therapies have not yet been effective in preventing the pathologic sequelae of NE exposure, but new therapies are being developed that offer both direct antiprotease activity and multifunctional anti-inflammatory properties.

Pathophysiology of Bronchiectasis

Bronchiectasis is a complex, heterogeneous disorder defined by both a radiological abnormality of permanent bronchial dilatation and a clinical syndrome. There are multiple underlying causes including severe infections, mycobacterial disease, autoimmune conditions, hypersensitivity disorders, and genetic conditions. The pathophysiology of disease is understood in terms of interdependent concepts of chronic infection, inflammation, impaired mucociliary clearance, and structural lung damage. Neutrophilic inflammation is characteristic of the disease, with elevated levels of harmful proteases such as neutrophil elastase associated with worse outcomes. Recent data show that neutrophil extracellular trap formation may be the key mechanism leading to protease release and severe bronchiectasis. Despite the dominant of neutrophilic disease, eosinophilic subtypes are recognized and may require specific treatments. Neutrophilic inflammation is associated with elevated bacterial loads and chronic infection with organisms such as Pseudomonas aeruginosa. Loss of diversity of the normal lung microbiota and dominance of proteobacteria such as Pseudomonas and Haemophilus are features of severe bronchiectasis and link to poor outcomes. Ciliary dysfunction is also a key feature, exemplified by the rare genetic syndrome of primary ciliary dyskinesia. Mucus symptoms arise through goblet cell hyperplasia and metaplasia and reduced ciliary function through dyskinesia and loss of ciliated cells. The contribution of chronic inflammation, infection, and mucus obstruction leads to progressive structural lung damage. The heterogeneity of the disease is the most challenging aspect of management. An understanding of the pathophysiology of disease and their biomarkers can help to guide personalized medicine approaches utilizing the concept of "treatable traits."

Protease-Antiprotease Imbalance in Bronchiectasis

Airway inflammation plays a central role in bronchiectasis. Protease-antiprotease balance is crucial in bronchiectasis pathophysiology and increased presence of unopposed proteases activity may contribute to bronchiectasis onset and progression. Proteases' over-reactivity and antiprotease deficiency may have a role in increasing inflammation in bronchiectasis airways and may lead to extracellular matrix degradation and tissue damage. Imbalances in serine proteases and matrix-metallo proteinases (MMPs) have been associated to bronchiectasis. Active neutrophil elastase has been associated with disease severity and poor long-term outcomes in this disease. Moreover, high levels of MMPs have been associated with radiological and disease severity. Finally, severe deficiency of α1-antitrypsin (AAT), as PiSZ and PiZZ (proteinase inhibitor SZ and ZZ) phenotype, have been associated with bronchiectasis development. Several treatments are under study to reduce protease activity in lungs. Molecules to inhibit neutrophil elastase activity have been developed in both oral or inhaled form, along with compounds inhibiting dipeptydil-peptidase 1, enzyme responsible for the activation of serine proteases. Finally, supplementation with AAT is in use for patients with severe deficiency. The identification of different targets of therapy within the protease-antiprotease balance contributes to a precision medicine approach in bronchiectasis and eventually interrupts and disrupts the vicious vortex which characterizes the disease.

Bronchial Infection and Temporal Evolution of Bronchiectasis in Patients With Chronic Obstructive Pulmonary Disease

BACKGROUND

Bronchiectasis (BE) impact the clinical course and prognosis of patients with chronic obstructive pulmonary disease (COPD). Yet, the temporal evolution of BE in these patients is unknown. This study seeks to assess the temporal evolution of BE in persons with COPD.

METHODS

201 moderate-to-severe patients were recruited between 2004 and 2007 and followed up at least every 6 monts (median of 102 months). To investigate the temporal evolution of BE, in 2015 a second high-resolution computed tomography scan (HRCT) was obtained in survivors and compared with the one obtained at recruitment.

RESULTS

99 (49.3%) died during follow-up. The second HRCT could be obtained in 77 patients and showed that (1) in 27.3% of patients BE never developed, in 36.4% they remained stable, in 16.9% they increased in size and/or extension, and in 19.5% new BE emerged; and that (2) the presence of chronic purulent sputum (hazard ratio [HR], 2.8 [95% confidence interval {CI}, 1.3-5.8]), number of hospitalizations due to exacerbatons (HR, 1.2 [95% CI, 1.1-1.5]), and number of pathogenic microorganism (PPM) isolations (HR, 1.1 [95% CI, 1.02-1.3]) were independent risk factors for the progression or development of BE.

CONCLUSIONS

The presence of chronic purulent sputum production, number of PPMs isolated in sputum, and number of hospitalizations due to exacerbations of COPD are independent risk factors of BE progression in patients with COPD.

Clinical features related to hospital expenses for non-cystic fibrosis bronchiectasis in China

Objective

Bronchiectasis is a common chronic airway disease. We investigated the economic burden and associated factors of bronchiectasis in China.

Methods

In this multicenter retrospective cohort study, we reviewed medical records of patients admitted to 18 tertiary hospitals during 2010 to 2014 with a bronchiectasis-related diagnosis.

Results

A total 5469 patients with bronchiectasis were admitted, accounting for 3.13% ± 1.80% of all discharged patients with any diagnosis during the same period; 13 patients died upon discharge. The median hospitalization cost was RMB 8421.52 (RMB 5849.88–12,294.47). Risk factors associated with hospitalization costs included age at admission (>70 vs. <40 years, odds ratio (OR) = 1.221, 95% confidence interval (CI) = 1.082–1.379; >80 vs. <40 years, OR = 1.251, 95% CI = 1.089–1.438), smoking (≤15 packs/year vs. non-smokers, OR = 1.125, 95% CI = 1.006–1.271; >15 packs/year vs. non-smokers, OR = 1.127, 95% CI = 1.062–1.228), length of hospitalization (OR = 1.05, 95% CI = 1.046–1.054), combination antibiotic treatment (OR = 1.089, 95% CI = 1.033–1.148), cough (OR = 0.851, 95% CI = 0.751–0.965), dyspnea (OR = 0.93, 95% CI = 0.878–0.984), chronic obstructive pulmonary disease (OR = 0.935, 95% CI = 0.878–0.996), respiratory failure (OR = 0.923, 95% CI = 0.862–0.989), cor pulmonale (OR = 0.919, 95% CI = 0.859–0.982), and death (OR = 1.816, 95% CI = 1.113–2.838).

Conclusions

Age, smoking status, symptoms, and respiratory comorbidities were associated with hospitalization costs of bronchiectasis.

Comorbidities and mortality risk factors for patients with bronchiectasis

Introduction: Comorbidities in patients with bronchiectasis are common and have a significant impact on clinical outcomes, contributing to lower quality of life, lung function, and exacerbation frequency. At least 13 comorbidities have been associated with a higher risk of mortality in bronchiectasis patients. Nonetheless, the kind of relationship between bronchiectasis and comorbidities is heterogeneous and poorly understood.Areas covered: different biological mechanisms leading to bronchiectasis could have a role in the development of the associated comorbidities. Some comorbidities could have a causal relationship with bronchiectasis, possibly through a variable degree of systemic inflammation, such as in rheumatic disorders and bowel inflammatory diseases. Other comorbidities, such as COPD or asthma, could be associated through airway inflammation and there is an uncertain cause-effect relationship. Finally, shared risk factors could link different comorbidities to bronchiectasis such as in the case of cardiovascular diseases, where the known link between chronic systemic inflammation and pulmonary infection could play a significant role.Expert opinion: Although different tools have been developed to assess the role of comorbidities in bronchiectasis , we believe that the implementation of current strategies to manage them is absolutely necessary and could significantly improve long-term prognosis in patients with bronchiectasis.

The role of high-flow nasal therapy in bronchiectasis: a post hoc analysis

High-flow nasal therapy (HFNT) is a gas delivery system that provides heated and humidified air or supplemental oxygen by nasal cannula. The role of HFNT in airways disease has primarily focused on COPD. Studies in patients with COPD have demonstrated improvement in quality-of-life scores and reduced acute exacerbations with HFNT use [1, 2].

High-flow nasal therapy significantly reduces exacerbation rates and improves quality of life in patients with stable bronchiectasis. High-flow nasal therapy is therefore a potential treatment option for patients with bronchiectasis.https://bit.ly/2JFXuQc

Neutrophil dysfunction in bronchiectasis: an emerging role for immunometabolism

Bronchiectasis is a heterogenous disease with multiple underlying causes. The pathophysiology is poorly understood but neutrophilic inflammation and dysfunctional killing of pathogens is believed to be key. There are, however, no licensed therapies for bronchiectasis that directly target neutrophilic inflammation. In this review, we discuss our current understanding of neutrophil dysfunction and therapeutic targeting in bronchiectasis. Immunometabolic reprogramming, a process through which inflammation changes inflammatory cell behaviour by altering intracellular metabolic pathways, is increasingly recognised across multiple inflammatory and autoimmune diseases. Here, we show evidence that much of the neutrophil dysfunction observed in bronchiectasis is consistent with immunometabolic reprogramming. Previous attempts at developing therapies targeting neutrophils have focused on reducing neutrophil numbers, resulting in increased frequency of infections. New approaches are needed and we propose that targeting metabolism could theoretically reverse neutrophil dysfunction and dysregulated inflammation. As an exemplar, 5' adenosine monophosphate (AMP)-activated protein kinase (AMPK) activation has already been shown to reverse phagocytic dysfunction and neutrophil extracellular trap (NET) formation in models of pulmonary disease. AMPK modulates multiple metabolic pathways, including glycolysis which is critical for energy generation in neutrophils. AMPK activators can reverse metabolic reprogramming and are already in clinical use and/or development. We propose the need for a new immunomodulatory approach, rather than an anti-inflammatory approach, to enhance bacterial clearance and reduce bronchiectasis disease severity.

Network Pharmacology Analysis of the Therapeutic Mechanisms Underlying Beimu-Gualou Formula Activity against Bronchiectasis with In Silico Molecular Docking Validation

Background

The classical Chinese herbal prescription Beimu-Gualou formula (BMGLF) has been diffusely applied to the treatment of respiratory diseases, including bronchiectasis. Although concerning bronchiectasis the effects and mechanisms of action of the BMGLF constituents have been partially elucidated, it remains to be determined how the formula in its entirety exerts therapeutic effects.

Methods

In this study, the multitarget mechanisms of BMGLF against bronchiectasis were predicted with network pharmacology analysis. Using prepared data, a drug-target interaction network was established and subsequently the core therapeutic targets of BMGLF were identified. Furthermore, the biological function and pathway enrichment of potential targets were analyzed to evaluate the therapeutic effects and pivotal signaling pathways of BMGLF. Finally, virtual molecular docking was performed to assess the affinities of compounds for the candidate targets.

Results

The therapeutic action of BMGLF against bronchiectasis involves 18 core target proteins, including the aforementioned candidates (i.e., ALB, ICAM1, IL10, and MAPK1), which are assumed to be related to biological processes such as drug response, cellular response to lipopolysaccharide, immune response, and positive regulation of NF-κB activity in bronchiectasis. Among the top 20 signaling pathways identified, mechanisms of action appear to be primarily related to Chagas disease, allograft rejection, hepatitis B, and inflammatory bowel disease.

Conclusion

In summary, using a network pharmacology approach, we initially predicted the complex regulatory profile of BMGLF against bronchiectasis in which multilink suppression of immune/inflammatory responses plays an essential role. These results may provide a basis for novel pharmacotherapeutic approaches for bronchiectasis.

Systemic Inflammation and Oxidative Stress in Adults with Bronchiectasis: Association with Clinical and Functional Features

OBJECTIVES

To compare the inflammatory and oxidative stress (OS) states of adults with bronchiectasis with those of healthy controls and correlate inflammatory and OS levels with lung function and physical capacity.

METHODS

This study used a cross-sectional design. Seventy-four adults with bronchiectasis (age: 49±15 years, forced expiratory volume in 1 second [FEV1]: 52.5±25.6%) and 42 healthy controls (age: 44±17 years, FEV1: 95.9±14.0%) performed cardiopulmonary exercise tests and incremental shuttle walking tests. Their physical activity in daily life, inflammatory cytokine, and antioxidant levels in plasma were measured.

RESULTS

Compared to that of the controls, the levels of interleukin (IL)-6 (p<0.001), IL-10 (p<0.001), carbonylated proteins (p=0.001), and superoxide anions (p=0.046) were significantly increased in adults with bronchiectasis. Catalase activity was also reduced in this group (p<0.001). The inflammatory markers IL-1β, IL-6, and tumor necrosis factor-α correlated negatively with aerobic capacity (r=-0.408, r=-0.308, and r=-0.207, respectively). We observed similar correlations with OS markers (thiobarbituric acid and carbonyls; r=-0.290 and r=0.379, respectively), and these markers also significantly correlated with the aerobic capacity.

CONCLUSIONS

Adults with bronchiectasis presented an increased systemic inflammatory response that correlated negatively with physical capacity.

A Cluster Analysis of Bronchiectasis Patients Based on the Airway Immune Profile

BACKGROUND

Clinical heterogeneity in bronchiectasis remains a challenge for improving the appropriate targeting of therapies and patient management. Antimicrobial peptides (AMPs) have been linked to disease severity and phenotype.

RESEARCH QUESTION

Can we identify clusters of patients based on the levels of AMPs, airway inflammation, tissue remodeling, and tissue damage to establish their relationship with disease severity and clinical outcomes?

STUDY DESIGN AND METHODS

A prospective cohort of 128 stable patients with bronchiectasis were recruited across three centers in three different countries (Spain, Scotland, and Italy). A two-step cluster strategy was used to stratify patients according to levels of lactoferrin, lysozyme, LL-37, and secretory leukocyte protease inhibitor in sputum. Measurements of inflammation (IL-8, tumor growth factor β, and IL-6), tissue remodeling and damage (glycosaminoglycan, matrix metallopeptidase 9, neutrophil elastase, and total and bacterial DNA), and neutrophil chemotaxis were assessed.

RESULTS

Three clusters of patients were defined according to distinct airway profiles of AMPs. They represented groups of patients with gradually distinct airway infection and disease severity. Each cluster was associated with an airway profile of inflammation, tissue remodeling, and tissue damage. The relationships between soluble mediators also were distinct between clusters. This analysis allowed the identification of the cluster with the most deregulated local innate immune response. During follow-up, each cluster showed different risk of three or more exacerbations occurring (P = .03) and different times to first exacerbations (P = .03).

INTERPRETATION

Bronchiectasis patients can be stratified in different clusters according to profiles of airway AMPs, inflammation, tissue remodeling, and tissue damage. The combination of these immunologic variables shows a relationship with disease severity and future risk of exacerbations.

The efficacy of inhaled hypertonic saline for bronchiectasis: a meta-analysis of randomized controlled studies

INTRODUCTION

The efficacy of inhaled hypertonic saline for bronchiectasis remains controversial. We conduct a systematic review and meta-analysis to explore the influence of inhaled hypertonic saline versus 0.9% isotonic saline for the treatment of bronchiectasis.

METHODS

We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through April 2020 for randomized controlled trials (RCTs) assessing the efficacy of inhaled hypertonic saline versus 0.9% isotonic saline for the treatment of bronchiectasis. This meta-analysis was performed using the random-effect model.

RESULTS

Four RCTs were included in the meta-analysis. Overall, compared with control group for bronchiectasis, inhaled hypertonic saline had no obvious influence on forced expiratory volume in 1 s (FEV1, SMD = 0.12; 95% CI = -0.06 to 0.30; P = .18), forced vital capacity (FVC, SMD = 0.10; 95% CI = -0.09 to 0.28; P = .30), sputum expectorated (SMD = -0.03; 95% CI = -2.73 to 2.68; P = .99) or Leicester Cough Questionnaire (LCQ) score (SMD = -0.15; 95% CI = -0.89 to 0.58; P = .68).

CONCLUSIONS

Inhaled hypertonic saline and 0.9% isotonic saline show similar efficacy for bronchiectasis.

Co-infection of SARS-CoV-2 and Bordetella bronchiseptica in a young man with idiopathic non-cystic bronchiectasis and vitamin D3 deficiency

This is the first reported case, to our knowledge, of co-infection of Bordetella bronchiseptica and SARS-CoV-2 in a young patient with underlying idiopathic bronchiectasis and vitamin D₃ deficiency that was treated successfully with a combination therapeutic regime integrating doxycycline, empiric therapies for COVID-19, vitamin D supplementation, and supportive ICU care. Large prospective studies are required to investigate further the role of co-infections in COVID-19 patients with bronchiectasis. Randomized control trials should examine the putative beneficial role of vitamin D supplementation in patients with COVID-19.

Prevalence and burden of bronchiectasis in a lung cancer screening program

INTRODUCTION

The prevalence of bronchiectasis in the general population and in individuals undergoing lung cancer screening with low dose computed tomography (LDCT) is unknown. The aim of this study is to estimate the prevalence and impact of bronchiectasis in a screening lung cancer program.

METHODS

3028 individuals participating in an international multicenter lung cancer screening consortium (I-ELCAP) were selected from 2000 to 2012. Patients with bronchiectasis on baseline CT were identified and compared to selected controls. Detection of nodules, need for additional studies and incidence of cancer were analyzed over the follow-up period.

RESULTS

The prevalence of bronchiectasis was 11.6%(354/3028). On the baseline LDCT, the number of subjects with nodules identified was 189(53.4%) in patients with bronchiectasis compared to 63(17.8%) in controls (p<0.001). The occurrence of false positives was higher in subjects with bronchiectasis (26%vs17%;p = 0.003). During follow-up, new nodules were more common among subjects with bronchiectasis (17%vs.12%; p = 0.008). The total number of false positives during follow-up was 29(17.06%) for patients with bronchiectasis vs. 88(12.17%) for controls (p = 0.008).The incidence rate of lung cancer during follow-up was 6.8/1000 and 5.1/1000 person-years for each group respectively (p = 0.62).

CONCLUSIONS

Bronchiectasis are common among current and former smokers undergoing lung cancer screening with LDCT. The presence of bronchiectasis is associated with greater incidence of new nodules and false positives on baseline and follow-up screening rounds. This leads to an increase need of diagnostic tests, although the lung cancer occurrence is not different.

Pregnancy Zone Protein Is Associated with Airway Infection, Neutrophil Extracellular Trap Formation, and Disease Severity in Bronchiectasis

Rationale: PZP (pregnancy zone protein) is a broad-spectrum immunosuppressive protein believed to suppress T-cell function during pregnancy to prevent fetal rejection. It has not previously been reported in the airway.

Objectives: To characterize PZP in the bronchiectasis airway, including its relationship with disease severity.

Methods: Label-free liquid chromatography/mass spectrometry was performed for sputum protein profiling of patients with bronchiectasis confirmed by high-resolution computed tomography. Results for patients with and without Pseudomonas aeruginosa infection were compared. Sputum and serum PZP was measured by validated ELISA. Airway infection status was established by culture and 16S ribosomal RNA sequencing. Immunofluorescence, ELISA, and electron microscopy were used to identify the cellular source of PZP in neutrophils treated with multiple stimuli.

Measurements and Main Results: Elevated PZP was identified by label-free liquid chromatography/mass spectrometry as being associated with P. aeruginosa infection. In a validation study of 124 patients, sputum but not serum concentrations of PZP were significantly associated with the Bronchiectasis Severity Index, the frequency of exacerbations, and symptoms. Airway infection with Proteobacteria such as P. aeruginosa was associated with higher concentrations of PZP. PZP in sputum was directly related to airway bacterial load. Neutrophils induced to form neutrophil extracellular traps (NETs) with phorbol myristate acetate released high concentrations of PZP in vitro, and fluorescence microscopy confirmed the presence of PZP in NETs, whereas fluorescence and electron microscopy localized PZP to the cytoplasm and nuclei of neutrophils. Effective antibiotic therapy reduced sputum PZP.

Conclusions: PZP is released into NETs. We report a novel link between airway infection, NET formation, and disease severity in bronchiectasis during chronic airway inflammation.

Assessment of Bronchiectasis in HIV Patients among an Urban Population

Bronchiectasis is characterized by permanent destruction of the airways that presents with productive cough, as well as bronchial wall thickening and luminal dilatation on computed tomographic (CT) scan of the chest; it is associated with high mortality. Accumulating data suggests higher rates of bronchiectasis among the HIV-positive population. This case series involves 14 patients with bronchiectasis and HIV followed at two major urban institutions from 1999 to 2018. Demographics, clinical presentation, microbiology, radiographic imaging, and outcomes were collected and compiled. Mean age was 42 years (range 12-77 years). 36% had a CD4 count greater than 500 cells/mm3, 28% had a CD4 count between 200 and 500 cells/mm3, and 36% had AIDS. 43% were treated for Pneumocystis jiroveci pneumonia (PJP) and 50% for Mycobacterium avium complex (MAC) infection. 21% had COPD, 7% had asthma, and 7% had a history of pulmonary aspergillosis. Two patients were followed up by pulmonary services after diagnosis of bronchiectasis on CT. The timeline of the follow-up in these cases was within months and after three years respectively. It is posited that the prevalence of bronchiectasis in HIV patients may be underestimated. Improving recognition and management of bronchiectasis could help diminish rehospitalization rates.

Total oxidant and antioxidant status and paraoxonase 1 levels of children with noncystic fibrosis bronchiectasis

Background/aim

To evaluate total oxidant status (TOS), total antioxidant capacity (TAC), and paraoxonase 1 (PON1) levels in children with noncystic fibrosis (CF) bronchiectasis (BE), and to compare these levels with those of healthy controls. The study parameters were also evaluated according to some demographic, anthropometric, and clinical characteristics, as well as lung functions.

Materials and methods

Enrolled in the study were 118 children with non-CF BE and 68 healthy controls. Serum TOS, TAC, and PON1 levels were determined. Lung function tests were performed by spirometry.

Results

Serum TOS was higher in the patients [median 9.54 (IQR 25–75 = 7.05–13.30) μmol H2O2 Eq/L] than in the healthy subjects [6.64 (5.45–9.53) μmol H2O2 Eq/L] (P < 0.001). TAC was higher in patients with non-CF BE [1.07 (1.0–1.07) mmol Trolox Eq/L] than in the healthy controls [0.87 (0.77–0.98) mmol Trolox Eq/L] (P < 0.001). In addition, serum PON1 levels were significantly higher in the patients [106.5 (42.5–154.2) U/L] than in the controls [47.7 (27.5–82.1) U/L] (P < 0.001). The patients with low FEV1 had decreased TAC when compared to those who had normal FEV1 in non-CF BE.

Conclusion

The present study demonstrated that compared with the control group the children with non-CF BE had elevated oxidative status, antioxidant defenses parameters, and PON1 values.

Brazilian consensus on non-cystic fibrosis bronchiectasis

Bronchiectasis is a condition that has been increasingly diagnosed by chest HRCT. In the literature, bronchiectasis is divided into bronchiectasis secondary to cystic fibrosis and bronchiectasis not associated with cystic fibrosis, which is termed non-cystic fibrosis bronchiectasis. Many causes can lead to the development of bronchiectasis, and patients usually have chronic airway symptoms, recurrent infections, and CT abnormalities consistent with the condition. The first international guideline on the diagnosis and treatment of non-cystic fibrosis bronchiectasis was published in 2010. In Brazil, this is the first review document aimed at systematizing the knowledge that has been accumulated on the subject to date. Because there is insufficient evidence on which to base recommendations for various treatment topics, here the decision was made to prepare an expert consensus document. The Brazilian Thoracic Association Committee on Respiratory Infections summoned 10 pulmonologists with expertise in bronchiectasis in Brazil to conduct a critical assessment of the available scientific evidence and international guidelines, as well as to identify aspects that are relevant to the understanding of the heterogeneity of bronchiectasis and to its diagnostic and therapeutic management. Five broad topics were established (pathophysiology, diagnosis, monitoring of stable patients, treatment of stable patients, and management of exacerbations). After this subdivision, the topics were distributed among the authors, who conducted a nonsystematic review of the literature, giving priority to major publications in the specific areas, including original articles, review articles, and systematic reviews. The authors reviewed and commented on all topics, producing a single final document that was approved by consensus.