Primary ciliary dyskinesia (PCD) is a rare, genetically heterogeneous, motile ciliopathy, characterized by neonatal respiratory distress, recurrent upper and lower respiratory tract infections, subfertility, and laterality defects. Diagnosis relies on a combination of tests for confirmation, including nasal nitric oxide (nNO) measurements, high-speed videomicroscopy analysis (HSVMA), immunofluorescent staining, axonemal ultrastructure analysis via transmission electron microscopy (TEM), and genetic testing. Notably, there is no single gold standard confirmatory or exclusionary test. Currently, 54 causative genes involved in cilia assembly, structure, and function have been linked to PCD; this rare disease has a spectrum of clinical manifestations and emerging genotype-phenotype relationships. In this review, we provide an overview of the structure and function of motile cilia, the emerging genetics and pathophysiology of this rare disease, as well as clinical features associated with motile ciliopathies, novel diagnostic tools, and updates on genotype-phenotype relationships in PCD.

The field of pediatric rare and diffuse lung disease continues its maturation as research advances the understanding of diagnosis and treatment of children\'s interstitial lung disease, noncystic fibrosis bronchiectasis, and primary ciliary dyskinesia. The rarity and breadth of these conditions make them challenging to study, yet we continue to make progress in our understanding of pathophysiology, genotype/phenotype relationships, and treatment. Papers published on these topics in Pediatric Pulmonology and other journals in 2023 describe the power of multicenter cooperation and patient registries, enhance our understanding of pathophysiology and genotype/phenotype relationships, and report progress in treatments. In this review, we hope to increase awareness and knowledge of these conditions and to inspire future research.

BACKGROUND: The pathophysiological mechanisms by which asthma and bronchiectasis are associated are still unclear. The association of these two diseases can result in more severe symptoms and a greater number of exacerbations.
OBJECTIVE: The aim of this systematic review is to collect evidence of the pathophysiology of non-cystic fibrosis bronchiectasis with associated asthma in children and adolescents, aged 6-18 years old.
METHODS: A systematic and comprehensive search will be performed using eight main databases, PubMed, PubMed PMC, BVS/BIREME, Scopus, EMBASE, Cochrane Library, Scielo and Web of Science. Articles will be searched from the earliest available time to July 2023. The studied population will be composed of children and adolescents with asthma and non-cystic fibrosis bronchiectasis. From the data obtained, all articles found will be transferred to the Rayyan platform. Study selection will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols Checklist (PRISMA P-2015). In addition, if sufficient data are available, a meta-analysis will be conducted. Two independent reviewers will conduct the studies selection, data extraction, and risk of bias assessment. The outcome measures will be to analyze if non-cystic fibrosis bronchiectasis is related to a specific inflammatory profile.
CONCLUSIONS: A systematic review will provide better knowledge about the etiopathogenesis and causes of the association between asthma and bronchiectasis and its role in the severity and control of asthma. Identifying, selecting and critically evaluating studies on asthma and bronchiectasis, would be possible to illuminate the characteristics of children and adolescents with associated diagnoses and provide information to help individualized treatments in order to control and prevent complications. The findings of this study will be published in a peer-reviewed journal.
BACKGROUND: The systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) in July 2023 (registration number CRD42023440355).

This review focuses on the latest advances in bronchiectasis from October 1st, 2022 to September 30th, 2023, including the etiology, diagnosis, treatment, comorbidities, and management of bronchiectasis in order to provide a reference in clinical diagnosis and treatment, and future research of bronchiectasis for domestic peers.
本文就2022年10月1日至2023年9月30日支气管扩张症领域的最新进展进行归纳总结，主要包括支扩的病因、诊断与治疗、合并症以及支扩的管理等方面，以期为国内同行的支扩临床诊治与研究提供帮助。.

BACKGROUND: Inhaled antibiotics are recommended conditionally by international bronchiectasis guidelines for the treatment of patients with bronchiectasis, but results of individual studies are inconsistent. A previous meta-analysis demonstrated promising results regarding the efficacy and safety of inhaled antibiotics in bronchiectasis. Subsequent publications have supplemented the existing body of evidence further in this area.
OBJECTIVE: To what extent do inhaled antibiotics demonstrate both efficacy and safety as a treatment option for adults with bronchiectasis?.
METHODS: Systematic review and meta-analysis of randomized controlled trials of inhaled antibiotics in adult patients with bronchiectasis. We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and ClinicalTrials.gov for eligible studies. Studies were included if they enrolled adults with bronchiectasis diagnosed by CT imaging and had a treatment duration of at least 4 weeks. The primary end point was exacerbation frequency, with additional key efficacy end points including severe exacerbations, bacterial load, symptoms, quality of life, and FEV1. Data were pooled through random-effects meta-analysis.
RESULTS: Twenty studies involving 3,468 patients were included. Inhaled antibiotics were associated with reduced number of patients with exacerbations (risk ratio, 0.85; 95% CI, 0.75-0.96), a slight reduction in exacerbation frequency (rate ratio [RR], 0.78; 95% CI, 0.68-0.91), a probable reduction in the frequency of severe exacerbations (RR, 0.48; 95% CI, 0.31-0.74), and a likely slight increase in time to first exacerbation (hazard ratio, 0.80; 95% CI, 0.68-0.94). Inhaled antibiotics likely lead to a slight increase in the Quality of Life-Bronchiectasis respiratory symptom score (2.51; 95% CI, 0.44-4.31) and may reduce scores on the St. George\'s Respiratory Questionnaire (-3.13; 95% CI, -5.93 to -0.32). Bacterial load consistently was reduced, but FEV1 was not changed with treatment. Evidence suggests little to no difference in adverse effects between groups (OR, 0.99; 95% CI, 0.75-1.30). Antibiotic-resistant organisms likely were increased by treatment.
CONCLUSIONS: Inhaled antibiotics result in a slight reduction in exacerbations, a probable reduction in severe exacerbations, and a likely slight improvement in symptoms and quality of life in adults with bronchiectasis.
BACKGROUND: International Prospective Register of Systematic Reviews; No.: CRD42023384694; URL: https://www.crd.york.ac.uk/prospero/.

BACKGROUND: Pseudomonas aeruginosa is the most commonly isolated pathogen in bronchiectasis and is associated with worse outcomes. Eradication treatment is recommended by guidelines, but the evidence base is limited. The expected success rate of eradication in clinical practice is not known.
METHODS: We conducted a systematic review and meta-analysis according to Meta-Analysis of Observational Studies in Epidemiology guidelines. PubMed, Embase, the Cochrane Database of Systematic Reviews and Clinicaltrials.gov were searched for studies investigating P. aeruginosa eradication treatment using antibiotics (systemic or inhaled) in patients with bronchiectasis. The primary outcome was the percentage of patients negative for P. aeruginosa at 12 months after eradication treatment. Cystic fibrosis was excluded.
RESULTS: Six observational studies including 289 patients were included in the meta-analysis. Our meta-analysis found a 12-month P. aeruginosa eradication rate of 40% (95% CI 34-45%; p<0.00001), with no significant heterogeneity (I2=0%). Combined systemic and inhaled antibiotic treatment was associated with a higher eradication rate (48%, 95% CI 41-55%) than systemic antibiotics alone (27%, 13-45%).
CONCLUSIONS: Eradication treatment in bronchiectasis results in eradication of P. aeruginosa from sputum in ∼40% of cases at 12 months. Combined systemic and inhaled antibiotics achieve higher eradication rates than systemic antibiotics alone.

Computed tomography (CT) imaging findings of pulmonary fibrosis are well established for adults and have been shown to correlate with prognosis and outcome. Recognition of fibrotic CT findings in children is more limited. With approved treatments for adult pulmonary fibrosis, it has become critical to define CT criteria for fibrosis in children, to identify patients in need of treatment and those eligible for clinical trials. Understanding how pediatric fibrosis compares with idiopathic pulmonary fibrosis and other causes of fibrosis in adults is increasingly important as these patients transition to adult care teams. Here, we review what is known regarding the features of pulmonary fibrosis in children compared with adults. Pulmonary fibrosis in children may be associated with genetic surfactant dysfunction disorders, autoimmune systemic disorders, and complications after radiation, chemotherapy, transplantation, and other exposures. Rather than a basal-predominant usual interstitial pneumonia pattern with honeycombing, pediatric fibrosis is primarily characterized by reticulation, traction bronchiectasis, architectural distortion, or cystic lucencies/abnormalities. Ground-glass opacities are more frequent in children with fibrotic interstitial lung disease than adults, and disease distribution appears more diffuse, without clearly defined axial or craniocaudal predominance. Following discussion and consensus amongst a panel of expert radiologists, pathologists and physicians, distinctive disease features were integrated to develop criteria for the first global Phase III trial in children with pulmonary fibrosis.

BACKGROUND: Using treatable traits as a management approach in bronchiectasis involves determining identifiable, clinically relevant, measurable and treatable problems to develop a management strategy in collaboration with the patient.
OBJECTIVE: To identify new treatable traits not previously reported in the literature and treatment strategies for new and existing traits that could be implemented in an outpatient clinic or community setting by an allied health professional or nurse in adults with bronchiectasis.
METHODS: A scoping review was conducted with searches of MEDLINE, CINAHL, AMED, Embase, Cochrane Central Register of Controlled Trials and PsycInfo. The search yielded 9963 articles with 255 articles proceeding to full text review and 114 articles included for data extraction.
RESULTS: Sixteen new traits were identified, including fatigue (number of studies with new trait (n) = 13), physical inactivity (n = 13), reduced peripheral muscle power and/or strength (n = 12), respiratory muscle weakness (n = 9) and sedentarism (n = 6). The main treatment strategies for new and existing traits were airway clearance therapy (number of citations (n) = 86), pulmonary rehabilitation (n = 58), inspiratory muscle training (n = 20) and nebulised saline (n = 12).
CONCLUSIONS: This review identifies several new traits in bronchiectasis and highlights the common treatments for new and existing traits that can be implemented in a treatable traits approach in an outpatient clinic or community setting by an allied health professional or nurse.

Chronic cough (CC; ≥8 weeks in duration) is a common and burdensome feature of respiratory diseases. The understanding of cough has progressed significantly in recent years, albeit largely in refractory (unexplained) chronic cough (RCC) in the absence of other respiratory conditions. The prevalence of CC in respiratory diseases is poorly described, but estimates have been reported: asthma (8-58%), chronic obstructive pulmonary disease (COPD; 10-74%), bronchiectasis (82-98%), interstitial lung disease (ILD; 50-89%) and sarcoidosis (3-64%). CC in respiratory conditions generally predicts impaired health status and more severe disease. It is associated with increased symptom burden and disease severity in asthma, COPD, bronchiectasis and ILD, higher exacerbation frequency in asthma and bronchiectasis, and increased mortality and lung transplantation in idiopathic pulmonary fibrosis (IPF). Physiologically, heightened cough reflex sensitivity (CRS) has been reported and postulated to be mechanistic in isolated RCC. Cough reflex hypersensitivity (CRH) has also been reported in asthma, COPD, bronchiectasis, ILD and sarcoidosis. Unlike recent advances in isolated RCC, there are limited studies and understanding of central cough neuropathways in other respiratory conditions. Of note, dysfunctional central voluntary cough suppression neuropathways and physiology were observed in isolation in RCC; cough suppression is preserved in COPD. Understanding in the mechanism of RCC cannot be simply extrapolated to other respiratory conditions. The restricted understanding of cough mechanisms in these conditions has limited cough-specific therapeutic options in this context. There is currently an unmet need to expand our understanding of cough in chronic respiratory conditions, both in order to improve the quality of life of patients, and to improve knowledge of cough in general. This review aims to describe the prevalence, impact, pathophysiology and management of CC in asthma, COPD, bronchiectasis, ILD and sarcoidosis.

Our objective in this review is to familiarize radiologists with the spectrum of initial and progressive CT manifestations of pulmonary complications observed in adult patients with primary immunodeficiency diseases, including primary antibody deficiency (PAD), hyper-IgE syndrome (HIES), and chronic granulomatous disease (CGD). In patients with PAD, recurrent pulmonary infections may lead to airway remodeling with bronchial wall-thickening, bronchiectasis, mucus-plugging, mosaic perfusion, and expiratory air-trapping. Interstitial lung disease associates pulmonary lymphoid hyperplasia, granulomatous inflammation, and organizing pneumonia and is called granulomatous-lymphocytic interstitial lung disease (GLILD). The CT features of GLILD are solid and semi-solid pulmonary nodules and areas of air space consolidation, reticular opacities, and lymphadenopathy. These features may overlap those of mucosa-associated lymphoid tissue (MALT) lymphoma, justifying biopsies. In patients with HIES, particularly the autosomal dominant type (Job syndrome), recurrent pyogenic infections lead to permanent lung damage. Secondary infections with aspergillus species develop in pre-existing pneumatocele and bronchiectasis areas, leading to chronic airway infection. The complete spectrum of CT pulmonary aspergillosis may be seen including aspergillomas, chronic cavitary pulmonary aspergillosis, allergic bronchopulmonary aspergillosis (ABPA)-like pattern, mixed pattern, and invasive. Patients with CGD present with recurrent bacterial and fungal infections leading to parenchymal scarring, traction bronchiectasis, cicatricial emphysema, airway remodeling, and mosaicism. Invasive aspergillosis, the major cause of mortality, manifests as single or multiple nodules, areas of airspace consolidation that may be complicated by abscess, empyema, or contiguous extension to the pleura or chest wall. CLINICAL RELEVANCE STATEMENT: Awareness of the imaging findings spectrum of pulmonary complications that can occur in adult patients with primary immunodeficiency diseases is important to minimize diagnostic delay and improve patient outcomes. KEY POINTS: • Unexplained bronchiectasis, associated or not with CT findings of obliterative bronchiolitis, should evoke a potential diagnosis of primary autoantibody deficiency. • The CT evidence of various patterns of aspergillosis developed in severe bronchiectasis or pneumatocele in a young adult characterizes the pulmonary complications of hyper-IgE syndrome. • In patients with chronic granulomatous disease, invasive aspergillosis is relatively frequent, often asymptomatic, and sometimes mimicking or associated with non-infectious inflammatory pulmonary lesions.