Pathophysiology, causes and genetics of paediatric and adult bronchiectasis

Characteristics of children readmitted with severe pneumonia in Kenyan hospitals

BACKGROUND

Pneumonia is a leading cause of childhood morbidity and mortality. Hospital re-admission may signify missed opportunities for care or undiagnosed comorbidities.

METHODS

We conducted a retrospective cohort study including children aged ≥ 2 months-14 years hospitalised with severe pneumonia between 2013 and 2021 in a network of 20 primary referral hospitals in Kenya. Severe pneumonia was defined using the 2013 World Health Organization criteria, and re-admission was based on clinical documentation from individual patient case notes. We estimated the prevalence of re-admission, described clinical management practices, and modelled risk factors for re-admission and inpatient mortality.

RESULTS

Among 20,603 children diagnosed with severe pneumonia, 2,274 (11.0%, 95% CI 10.6-11.5) were readmitted. Re-admission was independently associated with age (12-59 months vs. 2-11 months: adjusted odds ratio (aOR) 1.70, 1.54-1.87; >5 years vs. 2-11 months: aOR 1.85, 1.55-2.22), malnutrition (weight-for-age-z-score (WAZ) <-3SD vs. WAZ> -2SD: aOR 2.05, 1.84-2.29); WAZ - 2 to -3 SD vs. WAZ> -2SD: aOR 1.37, 1.20-1.57), wheeze (aOR 1.17, 1.03-1.33) and presence of a concurrent neurological disorder (aOR 4.42, 1.70-11.48). Chest radiography was ordered more frequently among those readmitted (540/2,274 [23.7%] vs. 3,102/18,329 [16.9%], p < 0.001). Readmitted patients more frequently received second-line antibiotics (808/2,256 [35.8%] vs. 5,538/18,173 [30.5%], p < 0.001), TB medication (69/2,256 [3.1%] vs. 298/18,173 [1.6%], p < 0.001), salbutamol (530/2,256 [23.5%] vs. 3,707/18,173 [20.4%], p = 0.003), and prednisolone (157/2,256 [7.0%] vs. 764/18,173 [4.2%], p < 0.001). Inpatient mortality was 2,354/18,329 (12.8%) among children admitted with a first episode of severe pneumonia and 269/2,274 (11.8%) among those who were readmitted (adjusted hazard ratio (aHR) 0.93, 95% CI 0.82-1.07). Age (12-59 months vs. 2-11 months: aHR 0.62, 0.57-0.67), male sex (aHR 0.81, 0.75-0.88), malnutrition (WAZ <-3SD vs. WAZ >-2SD: aHR 1.87, 1.71-2.05); WAZ - 2 to -3 SD vs. WAZ >-2SD: aHR 1.46, 1.31-1.63), complete vaccination (aHR 0.74, 0.60-0.91), wheeze (aHR 0.87, 0.78-0.98) and anaemia (aHR 2.14, 1.89-2.43) were independently associated with mortality.

CONCLUSIONS

Children readmitted with severe pneumonia account for a substantial proportion of pneumonia hospitalisations and deaths. Further research is required to develop evidence-based approaches to screening, case management, and follow-up of children with severe pneumonia, prioritising those with underlying risk factors for readmission and mortality.

ECFS standards of care on CFTR-related disorders: Identification and care of the disorders

This is the third paper in the series providing updated information and recommendations for people with cystic fibrosis transmembrane conductance regulator (CFTR)-related disorder (CFTR-RD). This paper covers the individual disorders, including the established conditions - congenital absence of the vas deferens (CAVD), diffuse bronchiectasis and chronic or acute recurrent pancreatitis - and also other conditions which might be considered a CFTR-RD, including allergic bronchopulmonary aspergillosis, chronic rhinosinusitis, primary sclerosing cholangitis and aquagenic wrinkling. The CFTR functional and genetic evidence in support of the condition being a CFTR-RD are discussed and guidance for reaching the diagnosis, including alternative conditions to consider and management recommendations, is provided. Gaps in our knowledge, particularly of the emerging conditions, and future areas of research, including the role of CFTR modulators, are highlighted.

Pathogenesis of nontypeable Haemophilus influenzae infections in chronic suppurative lung disease

The respiratory tract antimicrobial defense system is a multilayered defense mechanism that relies upon mucociliary clearance and components of both the innate and adaptive immune systems to protect the lungs from inhaled or aspirated microorganisms. One of these potential pathogens, nontypeable Haemophilus influenzae (NTHi), adopts several, multifaceted redundant strategies to successfully colonize the lower airways and establish a persistent infection. NTHi can impair mucociliary clearance, express multiple multifunctional adhesins for various cell types within the respiratory tract and evade host defenses by surviving within and between cells, forming biofilms, increasing antigenic drift, secreting proteases and antioxidants, and by host-pathogen cross-talk, impair macrophage and neutrophil function. NTHi is recognized as an important pathogen in several chronic lower respiratory disorders, such as protracted bacterial bronchitis, bronchiectasis, cystic fibrosis, and primary ciliary dyskinesia. The persistence of NTHi in human airways, including its capacity to form biofilms, results in chronic infection and inflammation, which can ultimately injure airway wall structures. The complex nature of the molecular pathogenetic mechanisms employed by NTHi is incompletely understood but improved understanding of its pathobiology will be important for developing effective therapies and vaccines, especially given the marked genetic heterogeneity of NTHi and its possession of phase-variable genes. Currently, no vaccine candidates are ready for large phase III clinical trials.

Bronchiectasis as co morbidity with COPD or ILD: complex interactions and severe consequences

Background

Bronchiectasis is a chronic pulmonary disease characterized by widened, malformed bronchi, with profuse expectoration and impaired quality of life. COPD and ILD are common co-morbidities with bronchiectasis.

Methods

The present study evaluated the clinical, laboratory& radiological characteristics of COPD and ILD with/without bronchiectasis. A hospital-based, retrospective study was conducted for 1 year.

Results

A total of 101 patients were analyzed, 60 patients had COPD, 34 had ILD and 7 patients had bronchiectasis without COPD or ILD. It was noticed that, out of the analyzed 60 COPD patients, 10 patients developed bronchiectasis (16.7%) versus10 patients of 34 ILD patients (29.4%). In COPD and ILD accompanied by bronchiectasis, the incidence of hemoptysis was significantly higher in comparison to those without bronchiectasis. Moreover, they showed a significant increase in partial pressure of carbon dioxide (PCO2) in comparison to those without bronchiectasis, as well as in comparison to bronchiectasis only. Sputum culture revealed that COPD with bronchiectasis were significantly associated with Staphlococcus aureus (77.8%), more than ILD with Bronchiectasis (33.3%). While S. pneumoniae were more evident in cases of ILD with bronchiectasis (22.2%). The bilateral, peripheral bronchiectasis was more common than the unilateral, central bronchiectasis among cases of COPD with bronchiectasis followed by ILD with bronchiectasis more than bronchiectasis only.

Conclusion

Patients with COPD /ILD with bronchiectasis can be associated with serious clinical manifestations as hemoptysis. Their sputum cultures detected more positive organisms than negative in comparison to cases of bronchiectasis only. Screening of COPD and ILD patients using HRCT Scanning is a recommended preventive measure for early detection of bronchiectasis.

Phage Therapy Administration Route, Regimen, and Need for Supplementary Antibiotics in Patients with Chronic Suppurative Lung Disease

Antimicrobial resistance is leading to increased mortality, posing risk to those with chronic suppurative lung disease (CSLD). One therapeutic option may be to target treatment-resistant bacteria using viruses (bacteriophages [phages]). Currently, patients receiving phage therapy on compassionate grounds may not be receiving optimal treatment as there is no defined approach for phage use. This review aims to explore administration route, regimen, and need for supplementary antibiotics in phage therapy to treat bacterial infection in CSLD. Twelve articles totaling 18 participants included details of numerous phage administration routes with varying regimens. All articles reported an initial reduction of bacterial load or an improvement in patient symptoms, highlighting the potential of phage therapy in CSLD. Fifteen out of 18 used supplementary antibiotics. Standardized protocols informed by high-quality research are necessary to ensure safe and effective phage therapy. In the interim, systematic recording of information within case reports may be useful.

Aspergillus Sensitization and Allergic Bronchopulmonary Aspergillosis in Asthmatic Children: A Systematic Review and Meta-Analysis

Background: The prevalence of aspergillus sensitization (AS) and allergic bronchopulmonary aspergillosis (ABPA) in asthmatic children remains unclear. Objective: To systematically review the literature to estimate the prevalence of AS and ABPA in children with bronchial asthma. Methods: We searched the PubMed and Embase databases for studies reporting the prevalence of AS or ABPA in pediatric asthma. The primary outcome was to assess the prevalence of AS, while the secondary outcome was to evaluate the prevalence of ABPA. We pooled the prevalence estimates using a random effects model. We also calculated the heterogeneity and publication bias. Results: Of the 11,695 records retrieved, 16 studies with 2468 asthmatic children met the inclusion criteria. Most studies were published from tertiary centers. The pooled prevalence of AS in asthma (15 studies; 2361 subjects) was 16.1% (95% confidence intervals [CI], 9.3-24.3). The prevalence of AS was significantly higher in prospective studies, studies from India, and those from developing countries. The pooled prevalence of ABPA in asthma (5 studies; 505 children) was 9.9% (95% CI, 0.81-27.6). There was significant heterogeneity and publication bias for both outcomes. Conclusions: We found a high prevalence of AS and ABPA in asthmatic children. There is a need for community-based studies from different ethnicities using a standard methodology to ascertain the true prevalence of AS and ABPA in pediatric asthma.

A Paradigm Shift in the Diagnosis of Aspiration Pneumonia in Older Adults

In older adults, community-acquired pneumonia (CAP) is often aspiration-related. However, as aspiration pneumonia (AP) lacks clear diagnostic criteria, the reported prevalence and clinical management vary greatly. We investigated what clinical factors appeared to influence the diagnosis of AP and non-AP in a clinical setting and reconsidered a more clinically relevant approach. Medical records of patients aged ≥75 years admitted with CAP were reviewed retrospectively. A total of 803 patients (134 APs and 669 non-APs) were included. The AP group had significantly higher rates of frailty, had higher SARC-F scores, resided in institutions, had neurologic conditions, previous pneumonia diagnoses, known dysphagia, and were more likely to present with vomiting or coughing on food. Nil by mouth orders, speech therapist referrals, and broad-spectrum antibiotics were significantly more common, while computed tomography scans and blood cultures were rarely performed; alternative diagnoses, such as cancer and pulmonary embolism, were detected significantly less. AP is diagnosed more commonly in frail patients, while aspiration is the underlying aetiology in most types of pneumonia. A presumptive diagnosis of AP may deny patients necessary investigation and management. We suggest a paradigm shift in the way we approach older patients with CAP; rather than trying to differentiate AP and non-AP, it would be more clinically relevant to recognise all pneumonia as just pneumonia, and assess their swallowing functions, causative organisms, and investigate alternative diagnoses or underlying causes of dysphagia. This will enable appropriate clinical management.

The role of viral infections in pulmonary exacerbations of patients with non-cystic fibrosis bronchiectasis: A systematic review

BACKGROUND

Bronchiectasis is a cause of increased morbidity of the respiratory system. Exacerbations among patients with non-CF (cystic fibrosis) bronchiectasis result in reduced pulmonary function and poor quality of life. While the role of bacteria in triggering exacerbations in patients with non- CF bronchiectasis has been well studied, little is known about viral infections in these patients. We aimed to review the evidence on the role of respiratory viruses in the exacerbations of non-CF bronchiectasis.

METHODS

Relevant literature was searched on the MEDLINE/PubMed database. Seven studies satisfied the criteria and were included in this review.

RESULTS

According to the included articles, respiratory viruses are often identified in exacerbations of patients with non-CF bronchiectasis with the most frequent being human rhinovirus and influenza viruses. When a virus is isolated during an exacerbation patients have more symptoms from the upper respiratory tract. One study showed that detection of Epstein- Barr virus among patients with non-CF bronchiectasis is correlated with faster reduction of pulmonary function and progression of the disease.

CONCLUSION

Viruses seem to have a role in the exacerbation of patients with non-CF bronchiectasis. However, the exact nature and importance of this role remain elusive. Viruses are also isolated during the stable period of the disease. Further well-designed studies are necessary to clarify this complex issue.

Prevalence and risk factors for postinfectious cough in discharged patients with coronavirus disease 2019 (COVID-19)

Background

Cough is one of the most common symptoms of coronavirus disease 2019 (COVID-19). However, the prevalence of persistent cough in recovered patients with COVID-19 during a longer follow-up remained unknown. This study aims to investigate the prevalence, and risk factors for postinfectious cough in COVID-19 patients after discharge.

Methods

We conducted a follow-up study for 129 discharged patients with laboratory-confirmed COVID-19 in two large hospitals located in Hubei Province, China from January 2020 to December 2020. Baseline demographics, comorbidities and smoking history were extracted from the medical record. Current symptoms and severity were recorded by a uniform questionnaire. Spirometry, diffuse function and chest computed tomography (CT) were performed on part of patients who were able to return to the outpatient department at follow-up.

Results

The median (interquartile range) follow-up time was 8.1 (7.9-8.5) months after discharge. The mean (standard deviation) age was 51.5 (14.9) years and 57 (44.2%) were male. A total of 27 (20.9%) patients had postinfectious cough (>3 weeks), 6 patients (4.7%) had persistent cough by the end of follow-up, including 3 patients with previous chronic respiratory diseases or current smoking. Other symptoms included dyspnea (6, 4.7%), sputum (4, 3.1%), fatigue (4, 3.1%), and anorexia (4, 3.1%) by the end of follow-up. Thirty-six of 41 (87.8%) patients showed impaired lung function or diffuse function, and 39 of 50 (78.0%) patients showed abnormal CT imaging. Patients with postinfectious cough demonstrated more severe and more frequent cough during hospitalization (P<0.001), and more chronic respiratory diseases (P=0.01). In multivariate logistic regression analysis, digestive symptoms during hospitalization [odds ratio (OR) 2.95, 95% confidence interval (CI): 1.10-7.92] and current smoking (OR 6.95, 95% CI: 1.46-33.14) were significantly associated with postinfectious cough of COVID-19.

Conclusions

A small part of patients developed postinfectious cough after recovery from COVID-19, few patients developed chronic cough in spite of a higher proportion of impaired lung function and abnormal lung CT image. Current smoking and digestive symptoms during hospitalization were risk factors for postinfectious cough in COVID-19.

Informatic analysis of the pulmonary microecology in non-cystic fibrosis bronchiectasis at three different stages

This study explored the impact of pulmonary microecological changes on disease progression in non-cystic fibrosis bronchiectasis (nCFB). A careful search of the NCBI BioProject database revealed the 16S rRNA-based microbiological testing results of 441 pulmonary sputum samples from patients in the relatively stable (baseline), acute exacerbation, or recovery stage. After preliminary analysis and screening, we selected 152 samples for further analyses, including determination of the operational taxonomic unit (OTU) distribution at the phylum, class, order, family and genus levels, community structure, alpha diversity, beta diversity, microbial multivariables, correlations, and community structure after the abundances of intragroup samples were averaged. The recovery group showed significant differences in pulmonary microbiological changes (P < 0.05) compared with the other groups. There were 30 differentially abundant OTUs, with 27 and 7 at the genus and phylum levels, respectively. The Chao1 value of the recovery group was comparable to that of the baseline group, and the Shannon and Simpson values of the recovery group were the highest. Rhodococcus in Actinobacteria was positively correlated with Ochrobactrum in Firmicutes. The differences in pulmonary microecological changes at different nCFB stages may serve as a biologically predictive indicator of nCFB progression.

Barriers and facilitators of physical activity in children with bronchiectasis: Perspectives from children and parents

BACKGROUND

Current bronchiectasis management guidelines recommend regular physical activity but a large proportion of children with bronchiectasis do not meet public health recommendations which call for 60 min or more of moderate-to-vigorous intensity physical activity daily. Knowing the factors that influence physical activity in children with bronchiectasis is necessary for the development of effective interventions to increase physical activity in this patient group. The objective of this study was to identify facilitators and barriers to physical activity in children with bronchiectasis unrelated to cystic fibrosis (CF) from the perspectives of children and their parents.

MATERIALS AND METHODS

This was a qualitative study informed by the theoretical domains framework (TDF). Children aged 7-15 years (8.8 years, 8.4-11.0) (median, interquartile range) and parents (45.8 years, 39.7-48.3) completed separate, semi-structured interviews (n = 21). Recordings were transcribed verbatim, and barriers and facilitators related to each TDF domain deductively coded. Emergent themes were inductively derived via consensus moderation.

RESULTS

From the perspectives of children, fun with friends, organized sport and activities, and family co-participation in physical activity emerged as facilitators. Inability to keep up with their peers and time on technology emerged as barriers. From the perspectives of parents, instrumental and logistic support for physical activity and supportive social and physical activity environments emerged as facilitators, while management of symptoms associated with bronchiectasis emerged as a barrier.

CONCLUSION

Programs to increase physical activity in children with bronchiectasis should be fun, accessible, provide opportunities for social interaction and address barriers related to exercise tolerance, perceived competence, and presence of respiratory symptoms.

25-Hydroxy vitamin D and body composition are associated with pulmonary function in non-cystic fibrosis bronchiectasis: A cross-sectional study

BACKGROUND

Previous studies have emphasized the effects of vitamin D on the lung function of cystic fibrosis (CF) adult patients. The main aim of the present study sought to determine the association between circulating 25-hydroxyvitamin D (25-OH D) concentration and clinical outcomes in non-cystic fibrosis (non-CF) bronchiectasis subjects. Secondary, we assessed the possible relationship between body composition and respiratory dysfunction in these patients.

MATERIALS AND METHODS

Sixty-two non-CF bronchiectasis patients (24 male/38 female), aged 18-72, were recruited in this cross-sectional study. Anthropometric indices, lung function tests, and bronchiectasis severity valuations were determined. Body composition, including Mid-arm muscle circumference (MAMC, cm) was calculated using triceps skinfold (TSF,mm) and mid-arm circumference (MAC,cm) under the reference formula. Then serum 25-hydroxyvitamin D concentration and C-reactive protein level were measured. The correlation between vitamin D level and pulmonary function and disease exacerbation tests was primarily assessed. Additionally, we evaluated the correlation between body composition and lung function tests.

RESULTS

Circulating 25-hydroxyvitamin D status positively was correlated with lung function tests, including FEV₁ (r = 0.30, p value = 0.035) and FVC (r = 0.36, p value = 0.011), and also be associated with the extent of pulmonary involvement (r = -0.34, p value = 0.03). There was a significant negative correlation between percentage body fat and respiratory function, FEV₁/FVC ratio (r = -0.43, p value < 0.001). In contrast, there was a strong correlation between skeletal muscle mass and pulmonary function tests (r = 0.26, p value = 0.04).

CONCLUSION

There is a positive association between low 25-hydroxyvitamin D status and lung dysfunction in participants with non-CF bronchiectasis. The pulmonary dysfunction also correlated with more percentage body fat and low skeletal muscle mass in these patients. Therefore, the evaluation of body composition and serum vitamin D are suggested in the disease management of the patients with non-CF bronchiectasis. However, these associations should be interpreted with caution due to the likelihood of reverse causation. More high-quality prospective studies are warranted to confirm our observations and determine the mechanisms underlying these findings.

Outcome and prognostic factors after lung transplantation for bronchiectasis other than cystic fibrosis

BACKGROUND

While lung transplant (LTX) can be an effective therapy to provide the survival benefit in selected populations, post-transplant outcome in LTX recipients with bronchiectasis other than cystic fibrosis (CF) has been less studied. Pseudomonas aeruginosa, often associated with exacerbations in bronchiectasis, is the most common micro-organism isolated from LTX recipients. We aimed to see the outcomes of patients with bronchiectasis other than CF after LTX and seek the risk factors associated with pre- and post-transplant Pseudomonas status.

METHODS

Patients who underwent LTX at Tohoku University Hospital between January 2000 and December 2020 were consecutively included into the retrospective cohort study. Pre- and post-transplant prevalence of Pseudomonas colonization between bronchiectasis and other diseases was reviewed. Post-transplant outcomes (mortality and the development of chronic lung allograft dysfunction (CLAD)) were assessed using a Cox proportional hazards and time-to-event outcomes were estimated using the Kaplan-Meier method.

RESULTS

LTX recipients with bronchiectasis experienced a high rate of pre- and post-transplant Pseudomonas colonization compared to other diseases with statistical significance (p < 0.001 and p < 0.001, respectively). Nevertheless, long-term survival in bronchiectasis was as great as non-bronchiectasis (Log-rank p = 0.522), and the bronchiectasis was not a trigger for death (HR 1.62, 95% CI 0.63-4.19). On the other hand, the chance of CLAD onset in bronchiectasis was comparable to non-bronchiectasis (Log-rank p = 0.221), and bronchiectasis was not a predictor of the development of CLAD (HR 1.88, 95% CI 0.65-5.40).

CONCLUSIONS

Despite high prevalence of pre- and post-transplant Pseudomonas colonization, the outcome in LTX recipients with bronchiectasis other than CF was comparable to those without bronchiectasis.

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."

New Perspectives in the Diagnosis and Management of Allergic Fungal Airway Disease

Allergy to airway-colonising, thermotolerant, filamentous fungi represents a distinct eosinophilic endotype of often severe lung disease. This endotype, which particularly affects adult asthma, but also complicates other airway diseases and sometimes occurs de novo, has a heterogeneous presentation ranging from severe eosinophilic asthma to lobar collapse. Its hallmark is lung damage, characterised by fixed airflow obstruction (FAO), bronchiectasis and lung fibrosis. It has a number of monikers including severe asthma with fungal sensitisation (SAFS) and allergic bronchopulmonary aspergillosis/mycosis (ABPA/M), but these exclusive terms constitute only sub-sets of the condition. In order to capture the full extent of the syndrome we prefer the inclusive term allergic fungal airway disease (AFAD), the criteria for which are IgE sensitisation to relevant fungi in association with airway disease. The primary fungus involved is Aspergillus fumigatus, but a number of other thermotolerant species from several genera have been implicated. The unifying mechanism involves germination of inhaled fungal spores in the lung in the context of IgE sensitisation, leading to a persistent and vigorous eosinophilic inflammatory response in association with release of fungal proteases. Most allergenic fungi, including Alternaria and Cladosporium species, are not thermotolerant and cannot germinate in the airways so only act as aeroallergens and do not cause AFAD. Studies of the airway mycobiome have shown that A. fumigatus colonises the normal as much as the asthmatic airway, suggesting it is the tendency to become IgE-sensitised that is the critical triggering factor for AFAD rather than colonisation per se. Treatment is aimed at preventing exacerbations with glucocorticoids and increasingly by the use of anti-T2 biological therapies. Anti-fungal therapy has a limited place in management, but is an effective treatment for fungal bronchitis which complicates AFAD in about 10% of cases.

Antimicrobial Resistance in Common Respiratory Pathogens of Chronic Bronchiectasis Patients: A Literature Review

Non-cystic fibrosis bronchiectasis is a chronic disorder in which immune system dysregulation and impaired airway clearance cause mucus accumulation and consequent increased susceptibility to lung infections. The presence of pathogens in the lower respiratory tract causes a vicious circle resulting in impaired mucociliary function, bronchial inflammation, and progressive lung injury. In current guidelines, antibiotic therapy has a key role in bronchiectasis management to treat acute exacerbations and chronic infection and to eradicate bacterial colonization. Contrastingly, antimicrobial resistance, with the risk of multidrug-resistant pathogen development, causes nowadays great concern. The aim of this literature review was to assess the role of antibiotic therapy in bronchiectasis patient management and possible concerns regarding antimicrobial resistance based on current evidence. The authors of this review stress the need to expand research regarding bronchiectasis with the aim to assess measures to reduce the rate of antimicrobial resistance worldwide.

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.

Unusual Bronchial Foreign Bodies with Localized Bronchiectasis in Five Children

Obstructive foreign bodies are uncommon causes of bronchiectasis in children, the causal relationship between foreign body aspiration and bronchiectasis remains unclear. We conducted a review of children who were diagnosed with bronchiectasis due to foreign body retention in a university hospital between 2014 and 2019. Five patents were studied (four boys, one girl; age range: 15 months to 13 years old). Computed tomography showed localized cylindrical bronchiectasis in all five patients. After removal of the foreign body by bronchoscopy, the prognoses were good. Patients with localized cylindrical bronchiectasis should be examined to exclude foreign body. As long as foreign body aspiration is diagnosed early and appropriately removed, the possibility of a lobectomy or even mortality is greatly reduced.

The Association of Airway Comorbidities With the Clinical Phenotypes and Outcomes of Patients With Antineutrophil Cytoplasmic Autoantibody-associated Vasculitis

OBJECTIVE

We investigated the association of airway comorbidities with the clinical phenotypes and outcomes of myeloperoxidase (MPO)-antineutrophil cytoplasmic antibodies (ANCA)-positive ANCA-associated vasculitis (AAV).

METHODS

An AAV patient multicenter cohort trial was established in 13 hospitals in western Japan between 2012 and 2018. We examined 143 of the new-onset MPO-ANCA-positive AAV patients. Their clinical characteristics and comorbidities at disease onset were compared based on clinical phenotypes. Multivariate analysis was performed to identify factors predictive of remission and death.

RESULTS

Twenty-seven cases with granulomatosis with polyangiitis (GPA), 10 with eosinophilic GPA (EGPA), 81 with microscopic polyangiitis (MPA), and 25 with unclassified AAV were identified. The average age of MPO-ANCA-positive patients was 71.4 years. Comorbidity (87.4%) and airway comorbidity (70.6%) were frequently observed in these patients. Examination of the clinical phenotypes revealed that the cases of GPA were frequently accompanied by infectious airway comorbidity (upper airway disease, bronchiectasis, pulmonary infections), and most of the cases of MPA and unclassified AAV were accompanied by fibrotic interstitial lung disease (fILD) or emphysema. Among MPO-ANCA-positive patients, infectious airway comorbidity was predictive of both remission (HR 1.58, P = 0.03) and mortality (HR 2.64, P = 0.04), and fILD was predictive of mortality (HR 7.55, P = 0.008). The combination of infectious airway comorbidities and fILD caused the worst survival outcomes in patients.

CONCLUSION

MPO-ANCA-positive AAV was frequently accompanied by airway comorbidities. In addition to fILD, infectious airway comorbidities were closely associated with those clinical phenotypes and outcomes.