Geographic variation in the aetiology, epidemiology and microbiology of bronchiectasis

The bronchiectasis microbiome: current understanding and treatment implications

PURPOSE OF REVIEW

Advances in DNA sequencing and analysis of the respiratory microbiome highlight its close association with bronchiectasis phenotypes, revealing fresh opportunities for diagnosis, stratification, and personalized clinical intervention. An under-recognized condition, bronchiectasis is increasingly the subject of recent large-scale, multicentre, and longitudinal clinical studies including detailed analysis of the microbiome. In this review, we summarize recent progress in our understanding of the bronchiectasis microbiome within the context of its potential use in treatment decisions.

RECENT FINDINGS

Diverse microbiome profiles exist in bronchiectasis, in line with the established disease heterogeneity including treatment response. Classical microbiology has established Pseudomonas aeruginosa and Haemophilus influenza as two microbial markers of disease, while holistic microbiome analysis has uncovered important associations with less common bacterial taxa including commensal an/or pathobiont species, including the emerging role of the fungal mycobiome, virome, and interactome. Integration of airway microbiomes with other high-dimensional biological and clinical datasets holds significant promise to determining treatable traits and mechanisms of disease related to the microbiome.

SUMMARY

The bronchiectasis microbiome is an emerging and key area of study with significant implications for understanding bronchiectasis, influencing treatment decisions and ultimately improving patient outcomes.

Type 2 Biomarkers and Their Clinical Implications in Bronchiectasis: A Prospective Cohort Study

PURPOSE

Bronchiectasis is predominantly marked by neutrophilic inflammation. The relevance of type 2 biomarkers in disease severity and exacerbation risk is poorly understood. This study explores the clinical significance of these biomarkers in bronchiectasis patients.

METHODS

In a cross-sectional cohort study, bronchiectasis patients, excluding those with asthma or allergic bronchopulmonary aspergillosis, underwent clinical and radiological evaluations. Bronchoalveolar lavage samples were analyzed for cytokines and microbiology. Blood eosinophil count (BEC), serum total immunoglobulin E (IgE), and fractional exhaled nitric oxide (FeNO) were measured during stable disease states. Positive type 2 biomarkers were defined by established thresholds for BEC, total IgE, and FeNO.

RESULTS

Among 130 patients, 15.3% demonstrated BEC ≥ 300 cells/μL, 26.1% showed elevated FeNO ≥ 25 ppb, and 36.9% had high serum total IgE ≥ 75 kU/L. Approximately 60% had at least one positive type 2 biomarker. The impact on clinical characteristics and disease severity was variable, highlighting BEC and FeNO as reflective of different facets of disease severity and exacerbation risk. The combination of low BEC with high FeNO appeared to indicate a lower risk of exacerbation. However, Pseudomonas aeruginosa colonization and a high neutrophil-to-lymphocyte ratio (NLR ≥ 3.0) were identified as more significant predictors of exacerbation frequency, independent of type 2 biomarker presence.

CONCLUSIONS

Our study underscores the distinct roles of type 2 biomarkers, highlighting BEC and FeNO, in bronchiectasis for assessing disease severity and predicting exacerbation risk. It advocates for a multi-biomarker strategy, incorporating these with microbiological and clinical assessments, for comprehensive patient management.

Prevalence of bronchiectasis in adults: a meta-analysis

BACKGROUND

Bronchiectasis, once considered an orphan disease, is receiving attention globally owing to its increasing prevalence, healthcare burden, and associated morbidity. However, the prevalence of bronchiectasis is unclear. This meta-analysis estimates the prevalence of bronchiectasis in adults, providing a valuable reference for future research.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science databases were searched from inception to May 31, 2024 for studies reporting the prevalence of bronchiectasis. Study selection, data extraction, and overall analysis of risk of the retrieved studies were conducted independently by two authors. The tool for assessing the risk of bias in prevalence studies was used to evaluate overall risk. Stata software (version 15.1) was used to performed the meta-analysis. Subgroup and sensitivity analyses were conducted to identify the source of heterogeneity. Funnel plots combined with Egger's test were used to detect publication bias.

RESULTS

The pooled prevalence of bronchiectasis in adults from 15 studies covering 437,851,478 individuals was 680 per 100,000 (95% CI: 634-727 per 100,000). Subgroup analysis showed that the prevalence of bronchiectasis in the United States, Korea, and China was 478 per 100,000 (95% CI: 367-588 per 100,000), 886 per 100,000 (95% CI: 778-993 per 100,000), and 759 per 100,000 (95% CI: 35-2399 per 100,000), respectively; 467 per 100,000 (95% CI: 416-518 per 100,000) in males and 535 per 100,000 (95% CI: 477-592 per 100,000) in females; 3958 per 100,000 (95% CI: 117-12637 per 100,000), 4677 per 100,000 (95% CI: 427-8928 per 100,000), and 3630 per 100,000 (95% CI: 158-7103 per 100,000) among never-smokers, ever-smokers, and current smokers, respectively; 430 per 100,000 (95% CI: 411-450 per 100,000), 380 per 100,000 (95% CI: 374-386 per 100,000), and 351 per 100,000 (95% CI: 342-360 per 100,000) among individuals with body mass index<18.5, 18.5-24.9, and ≥ 25, respectively. Sixteen comorbidities were evaluated in patients with bronchiectasis, revealing a high rate.

CONCLUSION

Bronchiectasis is not a rare disease and requires more attention from scientific researchers.

TRIAL REGISTRATION

The protocol for this review was registered with PROSPERO: CRD42023409216. Registered 26 June 2023.

Safety profile of drugs used in non-cystic fibrosis bronchiectasis: a narrative review

Non-cystic fibrosis bronchiectasis is a long-term lung disease characterised by abnormal dilatation of the bronchi, with patients experiencing chronic productive cough and recurrent exacerbations. Currently, there are no licensed drugs for use in bronchiectasis while clinical trials have been conducted to either test new drugs or repurpose existing ones. These drugs target the underlying pathophysiology of bronchiectasis which is known to include infection, inflammation, mucus hypersecretion and retention. Most of the drugs used in daily clinical practice for bronchiectasis are off-label with no randomised trials exploring their safety. This review aims at exploring the safety profile of drugs frequently used in clinical practice to manage bronchiectasis, including antibiotics (e.g. macrolides, aminoglycosides, polymyxins, fluoroquinolones, aztreonam), mucoactive therapy (e.g. hypertonic saline, mannitol, DNase and carbocisteine), anti-inflammatory therapy (inhaled corticosteroids) and drugs currently in development for use in bronchiectasis (e.g. brensocatib, benralizumab and itepekimab).

Eosinophilic Bronchiectasis: Prevalence, Severity, and Associated Features-A Cohort Study

Background: Bronchiectasis (BE) has been traditionally associated with neutrophilic inflammation, but eosinophilic bronchiectasis (EB) has recently emerged. Data about prevalence, clinical features, and disease severity are lacking. This study aimed to assess the EB prevalence, compare EB with non-EB, evaluate the Type-2 (T2) high endotype in BE (T2-high EB) versus non-T2-high EB, and identify EB predictors. Methods: We conducted a prospective study involving 153 BE patients. The data collected included clinical, radiological, and microbiological findings. BE severity was assessed using the bronchiectasis severity index (BSI), FACED and E-FACED scores, and the bronchiectasis etiology and comorbidity index (BACI). EB was defined as a blood eosinophil count (BEC) ≥ 300 cells/μL, and T2-high EB as BEC ≥ 300 cells/μL with fractional exhaled nitric oxide (FeNO) ≥ 25 ppb. Results: Prevalence was 27% for EB and 20% for T2-high EB. EB patients exhibited poorer lung function and more severe radiologic features, with significantly higher severity scores [BSI, FACED, E-FACED, BACI (p < 0.05)], and a higher median exacerbation rate [4 (2-5) in EB vs. 2 (1-4) in non-EB, p = 0.0002], compared with non-EB patients. T2-high EB patients showed higher severity scores [BSI, FACED, E-FACED (p < 0.05)], as well as worse lung function parameters [FEV1%, FVC%, FEF 25-75% (p < 0.05)] compared with non-T2-high EB patients. In our study, patients with EB exhibited notably worsened lung function and higher BE severity scores compared with their non-EB counterparts, with exacerbations playing a major role in these differences. We found statistically significant positive correlations between BEC and disease severity scores, such as BSI, FACED, and mMRC, as well as an inverse relationship with pulmonary function. The likelihood of EB being present was significantly higher in association with mMRC ≥ 1 (OR = 2.53; 95% CI, 1.26-5.64), exacerbations/year ≥ 1 (OR = 1.27; 95% CI, 1.0-1.63), and chronic PA colonization (OR = 3.9; 95% CI, 1.08-15.8). Conclusions: EB is a distinct endotype. Dyspnea, exacerbations, and PA colonization may be predictive of EB, emphasizing the importance of early detection for improved outcomes. BEC could serve as a useful biomarker of disease severity to consider when diagnosing EB.

The clinical impacts of lung microbiome in bronchiectasis with fixed airflow obstruction: a prospective cohort study

BACKGROUND

Airflow obstruction is a hallmark of disease severity and prognosis in bronchiectasis. The relationship between lung microbiota, airway inflammation, and outcomes in bronchiectasis with fixed airflow obstruction (FAO) remains unclear. This study explores these interactions in bronchiectasis patients, with and without FAO, and compares them to those diagnosed with chronic obstructive pulmonary disease (COPD).

METHODS

This prospective observational study in Taiwan enrolled patients with either bronchiectasis or COPD. To analyze the lung microbiome and assess inflammatory markers, bronchoalveolar lavage (BAL) samples were collected for 16S rRNA gene sequencing. The study cohort comprised 181 patients: 86 with COPD, 46 with bronchiectasis, and 49 with bronchiectasis and FAO, as confirmed by spirometry.

RESULTS

Patients with bronchiectasis, with or without FAO, had similar microbiome profiles characterized by reduced alpha diversity and a predominance of Proteobacteria, distinctly different from COPD patients who exhibited more Firmicutes, greater diversity, and more commensal taxa. Furthermore, compared to COPD and bronchiectasis without FAO, bronchiectasis with FAO showed more severe disease and a higher risk of exacerbations. A significant correlation was found between the presence of Pseudomonas aeruginosa and increased airway neutrophilic inflammation such as Interleukin [IL]-1β, IL-8, and tumor necrosis factor-alpha [TNF]-α, as well as with higher bronchiectasis severity, which might contribute to an increased risk of exacerbations. Moreover, in bronchiectasis patients with FAO, the ROSE (Radiology, Obstruction, Symptoms, and Exposure) criteria were employed to classify individuals as either ROSE (+) or ROSE (-), based on smoking history. This classification highlighted differences in clinical features, inflammatory profiles, and slight microbiome variations between ROSE (-) and ROSE (+) patients, suggesting diverse endotypes within the bronchiectasis with FAO group.

CONCLUSION

Bronchiectasis patients with FAO may exhibit two distinct endotypes, as defined by ROSE criteria, characterized by greater disease severity and a lung microbiome more similar to bronchiectasis without FAO than to COPD. The significant correlation between Pseudomonas aeruginosa colonization and increased airway neutrophilic inflammation, as well as disease severity, underscores the clinical relevance of microbial patterns. This finding reinforces the potential role of these patterns in the progression and exacerbations of bronchiectasis with FAO.

Development of a core outcome set for physiotherapy trials in adults with bronchiectasis (the COS-PHyBE study): A Delphi study and consensus meeting

Background

Physiotherapy is recommended for bronchiectasis management, but there is disparity in evidence supporting its use. This is partly because of inconsistency and poor reporting of outcomes in available studies. A Core Outcome Set (COS) may improve trial consistency and decrease reporting bias. This study aimed to develop a COS for physiotherapy clinical trials in adults with bronchiectasis.

Methods

A comprehensive list of outcomes was developed using a systematic review and qualitative semi-structured interviews with patients with bronchiectasis and physiotherapists.An international two-round online Delphi survey was conducted. Outcomes scored 7-9 (crucial) by ≥ 70 % of participants and 1-3 (not that important) by ≤ 15 % of participants from each stakeholder in the Likert scale were nominated for inclusion in the COS. Nominated outcomes and those considered crucial by only one of the stakeholders' groups were further discussed and voted in an international consensus meeting.

Results

A list of 137 outcomes was generated; 104 from literature and 33 from interviews. A Delphi survey containing 59 outcomes was completed by 171 participants from 20 countries. After the consensus meeting, representatives agreed on seven outcomes: health-related quality of life, respiratory symptoms, physical functioning, emotional and psychological functioning, fatigue, adherence to treatment, and functional exercise capacity.

Conclusion

A minimum set of seven outcomes are recommended to be included as measurements in future trials evaluating physiotherapy interventions for bronchiectasis.

Pseudomonas aeruginosa mucinous phenotypes and algUmucABD operon mutant characteristics obtained from inpatients with bronchiectasis and their correlation with acute aggravation

Objective

Although the mechanism is unclear, Pseudomonas aeruginosa (PA) infection directly affects the frequency of acute exacerbations in patients with bronchiectasis. The aims of this article are to analyze the genetic mutation characteristics of the algUmucABD operon in PA, isolated from hospitalized patients with bronchiectasis, and to explore independent risk factors for frequent acute exacerbations of bronchiectasis.

Methods

Based on the number of acute exacerbations that occurred in the past year, these patients with bronchiectasis were divided into those with frequent acute exacerbations (Group A) and those with non-frequent acute exacerbations (Group B). We identified the distribution of mucoid phenotypes (MPs) and alginate morphotypes (AMs) in PA, and classified them into I-IV categories based on their different AMs; otherwise, the gene mutation types (GMTs) of the algUmucABD operon were tested. Subsequently, the relationship between GMT, MP, and AM and the independent risk factors for frequent acute exacerbations in patients with bronchiectasis were explored.

Results

A total of 93 patients and 75 PA strains, from January 2019 to August 2023, were included in this study. The MP and AM distributions of PA were as follows: 64 strains (85.33%) of mucoid (the AMs were 38 strains of type I, 3 strains of type II, and 23 strains of type IV) and 11 strains of non-mucoid (the AM was type III only). Mucoid PA with algU, mucA, mucB, and mucD mutations accounted for 19.61%, 74.51%, 31.37%, and 50.98%, respectively. GMT was divided into the following: mucA mutations only, mucA combined with other gene mutations, other gene mutations without mucA mutations, and without gene mutations. In 91.7% of PA with type I of AM, only mucA mutations occurred, and in both separate MP and AM, the GMT differences were statistically significant. Lastly, the number of lung lobes with bronchiectasis and the number of PA with mucA mutations only were the independent risk factors for frequent acute exacerbations.

Conclusion

The mucA mutation was primarily responsible for the mucoid of MP and type I of AM in PA, and it was also an independent risk factor for frequent exacerbations of bronchiectasis.

Growing from common ground: nontuberculous mycobacteria and bronchiectasis

Bronchiectasis and nontuberculous mycobacteria (NTM) are intricately intertwined, with NTM capable of being both a cause and consequence of bronchiectatic disease. This narrative review focuses on the common ground of bronchiectasis and NTM pulmonary disease (NTM-PD) in terms of diagnostic approach, underlying risk factors and treatment strategies. NTM-PD diagnosis relies on a combination of clinical, radiological and microbiological criteria. Although their epidemiology is complicated by detection and reporting biases, the prevalence and pathogenicity of NTM species vary geographically, with Mycobacterium avium complex and Mycobacterium abscessus subspecies most frequently isolated in bronchiectasis-associated NTM-PD. Diagnosis of nodular bronchiectatic NTM-PD should prompt investigation of host factors, including disorders of mucociliary clearance, connective tissue diseases and immunodeficiencies, either genetic or acquired. Treatment of NTM-PD in bronchiectasis involves a multidisciplinary approach and considers the (sub)species involved, disease severity and comorbidities. Current guideline-based antimicrobial treatment of NTM-PD is considered long, cumbersome and unsatisfying in terms of outcomes. Novel treatment regimens and strategies are being explored, including rifampicin-free regimens and inclusion of clofazimine and inhaled antibiotics. Host-directed therapies, such as immunomodulators and cytokine-based therapies, might enhance antimycobacterial immune responses. Optimising supportive care, as well as pathogen- and host-directed strategies, is crucial, highlighting the need for personalised approaches tailored to individual patient needs. Further research is warranted to elucidate the complex interplay between host and mycobacterial factors, informing more effective management strategies.

Pathophysiology and genomics of bronchiectasis

Bronchiectasis is a complex and heterogeneous inflammatory chronic respiratory disease with an unknown cause in around 30-40% of patients. The presence of airway infection together with chronic inflammation, airway mucociliary dysfunction and lung damage are key components of the vicious vortex model that better describes its pathophysiology. Although bronchiectasis research has significantly increased over the past years and different endotypes have been identified, there are still major gaps in the understanding of the pathophysiology. Genomic approaches may help to identify new endotypes, as has been shown in other chronic airway diseases, such as COPD.Different studies have started to work in this direction, and significant contributions to the understanding of the microbiome and proteome diversity have been made in bronchiectasis in recent years. However, the systematic application of omics approaches to identify new molecular insights into the pathophysiology of bronchiectasis (endotypes) is still limited compared with other respiratory diseases.Given the complexity and diversity of these technologies, this review describes the key components of the pathophysiology of bronchiectasis and how genomics can be applied to increase our knowledge, including the study of new techniques such as proteomics, metabolomics and epigenomics. Furthermore, we propose that the novel concept of trained innate immunity, which is driven by microbiome exposures leading to epigenetic modifications, can complement our current understanding of the vicious vortex. Finally, we discuss the challenges, opportunities and implications of genomics application in clinical practice for better patient stratification into new therapies.

Bronchiectasis in Asia: a review of current status and challenges

Recent bronchiectasis studies from large-scale multinational, multicentre registries have demonstrated that the characteristics of the disease vary according to geographic region. However, most perspectives on bronchiectasis are dominated by data from Western countries. This review intends to provide an Asian perspective on the disease, focusing on the established registries in India, Korea and China. Asian patients with bronchiectasis are less likely to show female predominance and experience exacerbations, are more likely to be younger, have milder disease, and have fewer options for guideline-recommended treatment than those living in other global regions. Furthermore, Asian bronchiectasis patients demonstrate different comorbidities, microbiological profiles and unique endophenotypes, including post-tuberculosis and dry bronchiectasis. Notably, each Asian region reveals further geographic variations and inter-patient differences. Future studies are warranted to better characterise Asian patients with bronchiectasis.

Airway "Resistotypes" and Clinical Outcomes in Bronchiectasis

Rationale: Chronic infection and inflammation shapes the airway microbiome in bronchiectasis. Utilizing whole-genome shotgun metagenomics to analyze the airway resistome provides insight into interplay between microbes, resistance genes, and clinical outcomes. Objectives: To apply whole-genome shotgun metagenomics to the airway microbiome in bronchiectasis to highlight a diverse pool of antimicrobial resistance genes: the "resistome," the clinical significance of which remains unclear. Methods: Individuals with bronchiectasis were prospectively recruited into cross-sectional and longitudinal cohorts (n = 280), including the international multicenter cross-sectional Cohort of Asian and Matched European Bronchiectasis 2 (CAMEB 2) study (n = 251) and two independent cohorts, one describing patients experiencing acute exacerbation and a further cohort of patients undergoing Pseudomonas aeruginosa eradication treatment. Sputum was subjected to metagenomic sequencing, and the bronchiectasis resistome was evaluated in association with clinical outcomes and underlying host microbiomes. Measurements and Main Results: The bronchiectasis resistome features a unique resistance gene profile and increased counts of aminoglycoside, bicyclomycin, phenicol, triclosan, and multidrug resistance genes. Longitudinally, it exhibits within-patient stability over time and during exacerbations despite between-patient heterogeneity. Proportional differences in baseline resistome profiles, including increased macrolide and multidrug resistance genes, associate with shorter intervals to the next exacerbation, whereas distinct resistome archetypes associate with frequent exacerbations, poorer lung function, geographic origin, and the host microbiome. Unsupervised analysis of resistome profiles identified two clinically relevant "resistotypes," RT1 and RT2, the latter characterized by poor clinical outcomes, increased multidrug resistance, and P. aeruginosa. Successful targeted eradication in P. aeruginosa-colonized individuals mediated reversion from RT2 to RT1, a more clinically favorable resistome profile demonstrating reduced resistance gene diversity. Conclusions: The bronchiectasis resistome associates with clinical outcomes, geographic origin, and the underlying host microbiome. Bronchiectasis resistotypes link to clinical disease and are modifiable through targeted antimicrobial therapy.

Consistent efficacy and safety of sublingual immunotherapy tablets across allergens and geographic regions

Background: The clinical development program of the SQ grass, ragweed, tree, and house dust mite (HDM) sublingual immunotherapy (SLIT)-tablets for allergic rhinitis/conjunctivitis (AR/C) included clinical trials conducted in North America, Europe, and Japan. Objective: Data from these trials were analyzed to assess efficacy, immunologic mechanisms, and safety outcomes across allergens and geographic regions. Methods: Thirteen phase III, double-blind, placebo controlled trials in the subjects with AR/C were conducted in North America, Europe (including Russia), and Japan (N = 7763 analyzed). Trials were generally similar with respect to medical practice, target population, eligibility criteria, and efficacy and safety monitoring. Data were analyzed for the approved doses in North America and Europe. Four statistical models were used to enhance comparison of the efficacy end points among the trials. Results: The SLIT-tablets demonstrated consistent efficacy across allergens and regions, regardless of the statistical analysis used. Relative improvement in the primary efficacy end point compared with placebo by using the predefined protocol analysis ranged from 17.9% to 32.8%, 17.5% to 19.3%, 20.6% to 38.3%, and 39.6% with the grass, HDM, ragweed, and tree SLIT-tablets, respectively. The kinetics of specific immunoglobulin E (IgE) and IgG4 responses were similar among the allergens and regions. Local application-site reactions were the most common adverse events for all allergens and in all regions. Most treatment-related adverse events for all allergens and in all regions were mild in severity. The rate of systemic allergic reactions was similar across regions (0%-0.54%). Conclusion: Confirmatory phase III trials for SLIT-tablets in the treatment of AR/C showed consistent efficacy, immunologic, and safety outcomes across allergens and geographic regions.

Nontuberculous mycobacterial pulmonary disease added burden to COPD and bronchiectasis in Japan

Background and objective

Nontuberculous mycobacterial pulmonary disease (NTM-PD) prevalence in Japan is among the highest worldwide. COPD and bronchiectasis are common comorbidities among patients with NTM-PD, and it is challenging to treat NTM-PD in patients with these conditions. There are limited data on the incremental burden that NTM-PD adds to underlying COPD or bronchiectasis in Japan. Therefore, the objective of this study was to assess the incremental burden associated with NTM-PD in patients with pre-existing COPD and/or bronchiectasis.

Methods

This nested case-control study was based on JMDC, Inc. claims data (2015-2020). Patients with COPD and/or bronchiectasis with NTM-PD (cases) were age and sex matched 1:3 to patients with COPD and/or bronchiectasis without NTM-PD (controls), resulting in three mutually exclusive patient groups (COPD, bronchiectasis or both; with or without NTM-PD). Incremental burden of NTM-PD was assessed within each group by comparing hospitalisations during the 1-year period after NTM-PD diagnosis (index) between cases and controls with both univariate analysis and multivariate analysis adjusting for pre-index comorbidities.

Results

Univariate analyses in the three patient groups consistently demonstrated incremental hospitalisation burden in cases versus controls (e.g. COPD group: 20% of 492 cases versus 13% of 1476 controls had all-cause hospitalisations; 11% versus 5% had respiratory-related hospitalisations; and 6% versus 2% had COPD-related hospitalisations). Subsequent multivariate analysis further confirmed the findings.

Conclusions

The substantial incremental burden of hospitalisation associated with NTM-PD in patients with COPD and/or bronchiectasis highlights the urgent need for appropriate management of NTM-PD in Japan.

Biomarkers in bronchiectasis

Bronchiectasis is a heterogeneous disease with multiple aetiologies and diverse clinical features. There is a general consensus that optimal treatment requires precision medicine approaches focused on specific treatable disease characteristics, known as treatable traits. Identifying subtypes of conditions with distinct underlying biology (endotypes) depends on the identification of biomarkers that are associated with disease features, prognosis or treatment response and which can be applied in clinical practice. Bronchiectasis is a disease characterised by inflammation, infection, structural lung damage and impaired mucociliary clearance. Increasingly there are available methods to measure each of these components of the disease, revealing heterogeneous inflammatory profiles, microbiota, radiology and mucus and epithelial biology in patients with bronchiectasis. Using emerging biomarkers and omics technologies to guide treatment in bronchiectasis is a promising field of research. Here we review the most recent data on biomarkers in bronchiectasis.

Chest computed tomography findings among adult Aboriginal Australians with bronchiectasis in the Top End Northern Territory of Australia

INTRODUCTION

There is limited evidence in the literature illustrating chest computed tomography (CT) characteristics among adult Aboriginal Australians with bronchiectasis. This retrospective study evaluates the radiological characteristics of bronchiectasis in Aboriginal Australians residing in the Top End, Northern Territory of Australia.

METHODS

Patients aged >18 years with chest CT-confirmed bronchiectasis between 2011 and 2020 were included. Demographics and relevant clinical parameters were collected. Alongside confirming bronchiectasis, chest CT reports were assessed for (i) lobar location (ii) unilateral or bilateral involvement and (iii) bronchiectasis type when available.

RESULTS

A total of 459 patients were identified with chest CT-confirmed bronchiectasis, with a median age of 47 years, and 55% were females. Bronchiectasis was predominantly recorded in the left lower lobe (LLL) (73%), followed by the right lower lobe (RLL) (62%) and the left upper lobe (LUL) was least common (22%). Females recorded the right middle lobe (RML) affected significantly more often than males (50 vs. 34%, P = 0.012). Bilateral involvement was common (74%), with the strongest pairwise correlation associated between the right upper lobe (RUL) and LUL (P < 0.001). Cylindrical (50%) and cystic (28%) types were most common. The RML and LLL showed positive correlation with cylindrical and LUL with cystic bronchiectasis. Neither lobar location nor bronchiectasis type showed any significant association with lung function parameters other than RML, Lingula and LUL involvement being associated with better percent predicted values of diffusing capacity for carbon monoxide. There were no significant associations between sputum culture and type or lobar locations of bronchiectasis except for non-Aspergillus fungus culture prevalence was higher with cystic or cylindrical types.

CONCLUSION

The results of this study may be an avenue to develop CT bronchiectasis severity scale in the future specific for Aboriginal Australians.

Medical Causes of Hospitalisation among Patients with Bronchiectasis: A Nationwide Study in Japan

PURPOSE

Although the international guidelines for managing bronchiectasis are centred on preventing the exacerbation of bronchiectasis, the medical causes of admissions to hospital among patients with bronchiectasis have not been fully investigated.

METHODS

This study targeted patients with bronchiectasis who were admitted to hospitals between April 2018 and March 2020 using the national inpatient database in Japan. The causes of hospitalisation and types of antibiotics used for hospitalised patients were recorded.

RESULTS

In total, 21,300 hospitalisations of 16,723 patients with bronchiectasis were analysed. The most common cause was respiratory diseases in 15,145 (71.1%) admissions, including bacterial pneumonia and the exacerbation of bronchiectasis in 6238 (41.2%) and 3151 (20.8%), respectively. Antipseudomonal antibiotics were used in approximately 60% of patients with bacterial pneumonia who were administered antibiotic treatments and in approximately 50% of patients with the exacerbation of bronchiectasis.

CONCLUSIONS

Bacterial pneumonia was the most frequent cause of hospitalisation, followed by the exacerbation of bronchiectasis, among patients with bronchiectasis. Physicians need to focus on the prevention of bacterial pneumonia in addition to the exacerbation of bronchiectasis in patients with bronchiectasis.

Lung microbiome: new insights into bronchiectasis' outcome

The present treatments for bronchiectasis, which is defined by pathological dilatation of the airways, are confined to symptom relief and minimizing exacerbations. The condition is becoming more common worldwide. Since the disease's pathophysiology is not entirely well understood, developing novel treatments is critically important. The interplay of chronic infection, inflammation, and compromised mucociliary clearance, which results in structural alterations and the emergence of new infection, is most likely responsible for the progression of bronchiectasis. Other than treating bronchiectasis caused by cystic fibrosis, there are no approved treatments. Understanding the involvement of the microbiome in this disease is crucial, the microbiome is defined as the collective genetic material of all bacteria in an environment. In clinical practice, bacteria in the lungs have been studied using cultures; however, in recent years, researchers use next-generation sequencing methods, such as 16S rRNA sequencing. Although the microbiome in bronchiectasis has not been entirely investigated, what is known about it suggests that Haemophilus, Pseudomonas and Streptococcus dominate the lung bacterial ecosystems, they present significant intraindividual stability and interindividual heterogeneity. Pseudomonas and Haemophilus-dominated microbiomes have been linked to more severe diseases and frequent exacerbations, however additional research is required to fully comprehend the role of microbiome in the evolution of bronchiectasis. This review discusses recent findings on the lung microbiota and its association with bronchiectasis.

Bacteriophages for bronchiectasis: treatment of the future?

PURPOSE OF REVIEW

Bronchiectasis is a chronic respiratory disease characterized by dilated airways, persistent sputum production and recurrent infective exacerbations. The microbiology of bronchiectasis includes various potentially pathogenic microorganisms including Pseudomonas aeruginosa which is commonly cultured from patients' sputum. P. aeruginosa is difficult to eradicate and frequently exhibits antimicrobial resistance. Bacteriophage therapy offers a novel and alternative method to treating bronchiectasis and can be used in conjunction with antibiotics to improve patient outcome.

RECENT FINDINGS

Thirteen case reports/series to date have successfully used phages to treat infections in bronchiectasis patients, however these studies were constrained to few patients ( n  = 32) and utilized personalized phage preparations and adjunct antibiotics. In these studies, phage therapy was delivered by inhalation, intravenously or orally and was well tolerated in most patients without any unfavourable effects. Favourable clinical or microbiological outcomes were seen following phage therapy in many patients. Longitudinal patient follow-up reported regrowth of bacteria and phage neutralization in some studies. There are five randomized clinical controlled trials ongoing aiming to use phage therapy to treat P. aeruginosa associated respiratory conditions, with limited results available to date.

SUMMARY

More research, particularly robust clinical trials, into how phages can clear respiratory infections, interact with resident microbiota, and how bacteria might develop resistance will be important to establish to ensure the success of this promising therapeutic alternative.

Do Causes Influence Functional Aspects and Quality of Life in Patients with Nonfibrocystic Bronchiectasis?

Background

The denomination of noncystic fibrosis bronchiectasis (NCFB) includes several causes, and differences may be expected between the patient subgroups regarding age, comorbidities, and clinical and functional evolution. This study sought to identify the main causes of NCFB in a cohort of stable adult patients and to investigate whether such conditions would be different in their clinical, functional, and quality of life aspects.

Methods

Between 2017 and 2019, all active patients with NCFB were prospectively evaluated searching for clinical data, past medical history, dyspnea severity grading, quality of life data, microbiological profile, and lung function (spirometry and six-minute walk test).

Results

There was a female predominance; mean age was 54.7 years. Causes were identified in 82% of the patients, the most frequent being postinfections (n = 39), ciliary dyskinesia (CD) (n = 32), and chronic obstructive pulmonary disease (COPD) (n = 29). COPD patients were older, more often smokers (or former smokers) and with more comorbidities; they also had worse lung function (spirometry and oxygenation) and showed worse performance in the six-minute walk test (6MWT) (walked distance and exercise-induced hypoxemia). Considering the degree of dyspnea, in the more symptomatic group, patients had higher scores in the three domains and total score in SGRQ, besides having more exacerbations and more patients in home oxygen therapy.

Conclusions

Causes most identified were postinfections, CD, and COPD. Patients with COPD are older and have worse pulmonary function and more comorbidities. The most symptomatic patients are clinically and functionally more severe, besides having worse quality of life.

Nontuberculous Mycobacteria, Mucociliary Clearance, and Bronchiectasis

Nontuberculous mycobacteria (NTM) are environmental and ubiquitous, but only a few species are associated with disease, often presented as nodular/bronchiectatic or cavitary pulmonary forms. Bronchiectasis, airways dilatations characterized by chronic productive cough, is the main presentation of NTM pulmonary disease. The current Cole's vicious circle model for bronchiectasis proposes that it progresses from a damaging insult, such as pneumonia, that affects the respiratory epithelium and compromises mucociliary clearance mechanisms, allowing microorganisms to colonize the airways. An important bronchiectasis risk factor is primary ciliary dyskinesia, but other ciliopathies, such as those associated with connective tissue diseases, also seem to facilitate bronchiectasis, as may occur in Lady Windermere syndrome, caused by M. avium infection. Inhaled NTM may become part of the lung microbiome. If the dose is too large, they may grow excessively as a biofilm and lead to disease. The incidence of NTM pulmonary disease has increased in the last two decades, which may have influenced the parallel increase in bronchiectasis incidence. We propose that ciliary dyskinesia is the main promoter of bronchiectasis, and that the bacteria most frequently involved are NTM. Restoration of ciliary function and impairment of mycobacterial biofilm formation may provide effective therapeutic alternatives to antibiotics.

Association between Clinical Characteristics and Microbiota in Bronchiectasis Patients Based on Metagenomic Next-Generation Sequencing Technology

This study aimed to investigate the disparities between metagenomic next-generation sequencing (mNGS) and conventional culture results in patients with bronchiectasis. Additionally, we sought to investigate the correlation between the clinical characteristics of patients and their microbiome profiles. The overarching goal was to enhance the effective management and treatment of bronchiectasis patients, providing a theoretical foundation for healthcare professionals. A retrospective survey was conducted on 67 bronchiectasis patients admitted to The First Hospital of Jiaxing from October 2019 to March 2023. Clinical baseline information, inflammatory indicators, and pathogen detection reports, including mNGS, conventional blood culture, bronchoalveolar lavage fluid (BALF) culture, and sputum culture results, were collected. By comparing the results of mNGS and conventional culture, the differences in pathogen detection rate and pathogen types were explored, and the diagnostic performance of mNGS compared to conventional culture was evaluated. Based on the various pathogens detected by mNGS, the association between clinical characteristics of bronchiectasis patients and mNGS microbiota results was analyzed. The number and types of pathogens detected by mNGS were significantly larger than those detected by conventional culture. The diagnostic efficacy of mNGS was significantly superior to conventional culture for all types of pathogens, particularly in viral detection (p < 0.01). Regarding pathogen detection rate, the bacteria with the highest detection rate were Pseudomonas aeruginosa (17/58) and Haemophilus influenzae (11/58); the fungus with the highest detection rate was Aspergillus fumigatus (10/21), and the virus with the highest detection rate was human herpes virus 4 (4/11). Differences were observed between the positive and negative groups for P. aeruginosa in terms of common scoring systems for bronchiectasis and whether the main symptom of bronchiectasis manifested as thick sputum (p < 0.05). Significant distinctions were also noted between the positive and negative groups for A. fumigatus regarding Reiff score, neutrophil percentage, bronchiectasis etiology, and alterations in treatment plans following mNGS results reporting (p < 0.05). Notably, 70% of patients with positive A. fumigatus infection opted to change their treatment plans. The correlation study between clinical characteristics of bronchiectasis patients and mNGS microbiological results revealed that bacteria, such as P. aeruginosa, and fungi, such as A. fumigatus, were associated with specific clinical features of patients. This underscored the significance of mNGS in guiding personalized treatment approaches. mNGS could identify multiple pathogens in different types of bronchiectasis samples and was a rapid and effective diagnostic tool for pathogen identification. Its use was recommended for diagnosing the causes of infections in bronchiectasis patients.

Epidemiology and outcomes of multidrug-resistant bacterial infection in non-cystic fibrosis bronchiectasis

PURPOSE

Multidrug-resistant (MDR) bacteria impose a considerable health-care burden and are associated with bronchiectasis exacerbation. This study investigated the clinical outcomes of adult patients with bronchiectasis following MDR bacterial infection.

METHODS

From the Chang Gung Research Database, we identified patients with bronchiectasis and MDR bacterial infection from 2008 to 2017. The control group comprised patients with bronchiectasis who did not have MDR bacterial infection and were propensity-score matched at a 1:2 ratio. The main outcomes were in-hospital and 3-year mortality.

RESULTS

In total, 554 patients with both bronchiectasis and MDR bacterial infection were identified. The types of MDR bacteria that most commonly affected the patients were MDR- Acinetobacter baumannii (38.6%) and methicillin-resistant Staphylococcus aureus (18.4%), Extended-spectrum-beta-lactamases (ESBL)- Klebsiella pneumoniae (17.8%), MDR-Pseudomonas (14.8%), and ESBL-E. coli (7.5%). Compared with the control group, the MDR group exhibited lower body mass index scores, higher rate of chronic bacterial colonization, a higher rate of previous exacerbations, and an increased use of antibiotics. Furthermore, the MDR group exhibited a higher rate of respiratory failure during hospitalization (MDR vs. control, 41.3% vs. 12.4%; p < 0.001). The MDR and control groups exhibited in-hospital mortality rates of 26.7% and 7.6%, respectively (p < 0.001); 3-year respiratory failure rates of 33.5% and 13.5%, respectively (p < 0.001); and 3-year mortality rates of 73.3% and 41.5%, respectively (p < 0.001). After adjustments were made for confounding factors, the infection with MDR and MDR bacteria species were determined to be independent risk factors affecting in-hospital and 3-year mortality.

CONCLUSIONS

MDR bacteria were discovered in patients with more severe bronchiectasis and were independently associated with an increased risk of in-hospital and 3-year mortality. Given our findings, we recommend that clinicians identify patients at risk of MDR bacterial infection and follow the principle of antimicrobial stewardship to prevent the emergence of resistant bacteria among patients with bronchiectasis.

Pneumonia due to Achromobacter xylosoxidans with a chronic course resembling non-tuberculous mycobacterial infection

Achromobacter xylosoxidans is a common bacterium that rarely causes pneumonia. Determining whether A. xylosoxidans is the cause of lung infection in patients suspected of having chronic infectious lung disease is challenging because it can present with colonization. We report a case of a 56-year-old immunocompetent woman suspected of having non-tuberculous mycobacteria (NTM) infection on imaging examination and monitored for 3 years. Sputum examinations revealed A. xylosoxidans several times, and it was determined to be a colonization. A. xylosoxidans was isolated from bronchial lavage fluid and aspirated sputum, but no evidence of NTM was observed. She was diagnosed with A. xylosoxidans infection and given ceftazidime for 2 weeks. Her symptoms and imaging findings improved rapidly after treatment, without recurrences. A. xylosoxidans rarely causes chronic lower respiratory tract infections similar to NTM in immunocompetent patients. A. xylosoxidans may be a target for treatment when detected in lower respiratory tract specimens.

Understanding the effects of Haemophilus influenzae colonization on bronchiectasis: a retrospective cohort study

BACKGROUND

Bacterial colonization is an essential aspect of bronchiectasis. Although Haemophilus influenzae is a frequent colonizer in some regions, its clinical impacts are poorly understood. This study aimed to elucidate the impact of H. influenzae colonization in patients with bronchiectasis.

METHODS

This retrospective study screened adult patients diagnosed with bronchiectasis at a tertiary referral center between April 1, 2003, and May 16, 2021, in South Korea. Propensity score matching was used to match patients with and without H. influenzae colonization. We assessed the severity of bronchiectasis as per the bronchiectasis severity index, the incidence of exacerbation, differences in lung function, and all-cause mortality.

RESULTS

Out of the 4,453 patients with bronchiectasis, 79 (1.8%) were colonized by H. influenzae. After 1:2 propensity score matching, 78 and 154 patients were selected from the H. influenzae colonizer and non-colonizer groups, respectively. Although there were no significant differences between the groups regarding baseline demographics, patients colonized with H. influenzae had a higher bronchiectasis severity index (median 6 [interquartile range 4-8] vs. 4 [2-7], p = 0.002), associated with extensive radiographic involvement (52.2% vs. 37.2%, p = 0.045) and mild exacerbation without hospitalization (adjusted incidence rate ratio 0.15; 95% confidence interval 0.12-0.24). Lung function and mortality rates did not reveal significant differences, regardless of H. influenzae colonization.

CONCLUSION

H. influenzae colonization in bronchiectasis was associated with more severe disease and greater incidence of mild exacerbation, but not lung function and mortality. Attention should be paid to patients with bronchiectasis with H. influenzae colonization.

Changes in the airway microbiome in patients with bronchiectasis

This study used metagenomic next-generation sequencing (mNGS) technology to explore the changes of the microbial characteristics in the lower respiratory tract in patients with acute exacerbations of bronchiectasis (noncystic fibrosis) to guide clinical treatment and improve patients' quality of life and prognosis. This prospective study included 54 patients with acute exacerbation and 46 clinically stable patients admitted to the Respiratory and Critical Care Medicine Center of the People's Hospital of Xinjiang Uygur Autonomous Region from January 2020 to July 2022. Sputum was subjected to routine microbiological tests, and bronchoalveolar lavage fluid (BALF) samples were subjected to microbiological tests and mNGS of BALF before empirical antibiotic therapy. Serum inflammatory markers (white blood cell count, interleukin-6, procalcitonin, and C-reactive protein) were measured. In addition, we evaluated the pathogen of mNGS and compared the airway microbiome composition of patients with acute exacerbation and control patients. The mean age of our cohort was 56 ± 15.2 years. Eighty-nine patients had positive results by mNGS. There was a significant difference in the detection of viruses between the groups (χ2 = 6.954, P < .01). The fungal species Candida albicans, Pneumocystis jirovecii, and Aspergillus fumigatus were significantly more common in patients with acute exacerbations (χ2 = 5.98, P = .014). The bacterial species Acinetobacter baumannii, Mycobacterium tuberculosis, Haemophilus influenzae, Haemophilus parahaemolyticus, Abiotrophia defectiva, and Micromonas micros were significantly more prevalent in patients with acute exacerbations (χ2 = 4.065, P = .044). The most common bacterial species isolated from the sputum and BALF samples of patients with acute exacerbation was A. baumannii. Chlamydia psittaci was found in 4 patients. In addition, of 77 patients with negative sputum culture, 66 had positive results by mNGS, demonstrating the increased sensitivity and accuracy of mNGS. Patients with acute exacerbation of bronchiectasis tend to have mixed infections in the lower respiratory tract. The frequency of viruses, fungi, and Mycoplasma was higher in these patients. Our findings suggest that mNGS could be used to identify pathogenic microorganisms in these patients, increasing the effectiveness of antibiotic therapy.

Expert group recommendation on inhaled mucoactive drugs in pediatric respiratory diseases: an Indian perspective

Background

Currently, there are no guidelines or consensus statements about the usage of inhaled mucoactive drugs in pediatric respiratory disease conditions from an Indian perspective.

Objective

To develop a practical consensus document to help pediatricians in clinical decision-making when choosing an appropriate mucoactive drug for the management of specific respiratory disease conditions.

Methods

A committee of nine experts with significant experience in pediatric respiratory disease conditions and a microbiological expert constituted the panel. An electronic search of the PubMed/MEDLINE, Cochrane Library, Scopus, and Embase databases was undertaken to identify relevant articles. Various combinations of keywords such as inhaled, nebulized, mucoactive, mucolytic, mucokinetic, expectorants, mucoregulators, mucociliary clearance, respiratory disorders, pediatric, cystic fibrosis (CF), non-CF bronchiectasis, acute wheezing, asthma, primary ciliary dyskinesia (PCD), critically ill, mechanical ventilation, tracheomalacia, tracheobronchomalacia, esophageal atresia (EA), tracheoesophageal fistula (TEF), acute bronchiolitis, sputum induction, guideline, and management were used. Twelve questions were drafted for discussion. A roundtable meeting of experts was conducted to arrive at a consensus. The level of evidence and class of recommendation were weighed and graded.

Conclusions

Inhaled mucoactive drugs (hypertonic saline, dry powder mannitol, and dornase alfa) can enhance mucociliary clearance in children with CF. Experts opined that hypertonic saline could be beneficial in non-CF bronchiectasis, acute bronchiolitis, and PCD. The current state of evidence is inadequate to support the use of inhaled mucoactive drugs in asthma, acute wheezing, tracheomalacia, tracheobronchomalacia, and EA with TEF.

Pneumonectomy for severe post-tuberculosis bronchiectasis: A successful of case report and review of the long-term outcome

Limited clinical intervention studies highlight the absence of evidence-based international guidelines for effectively managing post-tuberculosis lung disease, emphasizing bronchiectasis. The aim of this study was to describe a case of left pneumonectomy for severe post-tuberculosis cystic bronchiectasis and to provide a review of the post-surgical mortality rate, complications, survival rate, and the patient's quality of life following the pneumonectomy procedure. A 36-year-old Indonesian male smoker presented with worsening breathing difficulties and fever. The patient had a history of pulmonary tuberculosis six years ago and reported negative tuberculosis tests after completing TB treatment. However, lung function of the patient progressively declined over the years. Bronchoscopy, chest X-ray, and high-resolution computerized tomography (CT) scan revealed infected cystic bronchiectasis and identified a prominent left lung collapse with calcification in the left pleura. The patient underwent left pneumonectomy through left posterolateral thoracotomy under general anesthesia. The patient was discharged after seven post-operative days with no eventful course. No further complications were found after a one-year post-surgery follow-up, and the patient returned to normal activities, improved fitness, and was fitter in daily life. Based on the literature review, post-surgical mortality rates of pneumonectomy are acceptable, with bronchopleural fistula, cardiac arrest, and thoracic hemorrhage being common causes. Yet, the chances of a complete cure are high. Complications can occur in approximately one-third of patients, including arrhythmia, pulmonary infection, fever, and wound infections. The overall 5-year survival rate following pneumonectomy is generally favorable. Regarding the quality of life, pneumonectomy can have mixed effects. While it could improve symptoms and quality of life, it may impair the quality of life for certain patients, particularly elderly patients and those with lower preoperative quality of life. Although the post-surgical mortality rate, complications, and long-term survival rates of pneumonectomy are generally satisfactory, the expectation of improved post-surgical quality of life should be discussed with the patient prior to surgery.

A case-control study on the risk factors associated with the occurrence of non-tuberculous mycobacteria pulmonary disease in bronchiectasis patients

OBJECTIVE

The objective of this study is to analyze the risk factors associated with bronchiectasis combined with non-tuberculous mycobacteria pulmonary disease(NTM-PD) and provide a basis for more effective prevention and treatment strategies.

METHODS

The study subjects for this manuscript were patients with bronchiectasis who were admitted to the infection department between January 2021 and June 2023.There were 34 patients with NTM-PD in the observation group, and 52 patients with simple bronchiectasis in the control group. Basic information, imaging features, serum albumin levels, and infection indicators were collected from both groups of patients.Univariate and multivariate logistic regression analysis were performed to analyze the risk factors for NTM-PD in patients with bronchiectasis.

RESULTS

Multivariate logistic regression analysis revealed that bronchiectasis exacerbation occurring at least twice a year(OR = 3.884, 95% CI: 1.200-12.568), involvement of three or more lung lobes with bronchiectasis (OR = 3.932, 95% CI: 1.208-12.800), hypoalbuminemia (OR = 3.221, 95% CI: 1.015-10.219), and the NLR index (OR = 1.595, 95% CI: 1.200-2.119) were significant risk factors for non-tuberculous mycobacteria pulmonary disease in individuals with bronchiectasis (P < 0.05).

CONCLUSION

Patients with bronchiectasis accompanied by NTM-PD present specific risk factors that should be promptly addressed through prevention and treatment.

Endotypes in bronchiectasis: moving towards precision medicine. A narrative review

Bronchiectasis is a highly complex entity that can be very challenging to investigate and manage. Patients are diverse in their aetiology, symptoms, risk of complications and outcomes. "Endotypes"- subtypes of disease with distinct biological mechanisms, has been proposed as a means of better managing bronchiectasis. This review discusses the emerging field of endotyping in bronchiectasis. We searched PubMed and Google Scholar for randomized controlled trials (RCT), observational studies, systematic reviews and meta-analysis published from inception until October 2022, using the terms: "bronchiectasis", "endotypes", "biomarkers", "microbiome" and "inflammation". Exclusion criteria included commentaries and non-English language articles as well as case reports. Duplicate articles between databases were initially identified and appropriately excluded. Studies identified suggest that it is possible to classify bronchiectasis patients into multiple endotypes deriving from their co-morbidities or underlying causes to complex infective or inflammatory endotypes. Specific biomarkers closely related to a particular endotype might be used to determine response to treatment and prognosis. The most clearly defined examples of endotypes in bronchiectasis are the underlying causes such as immunodeficiency or allergic bronchopulmonary aspergillosis where the underlying causes are clearly related to a specific treatment. The heterogeneity of bronchiectasis extends, however, far beyond aetiology and it is now possible to identify subtypes of disease based on inflammatory mechanisms such airway neutrophil extracellular traps and eosinophilia. In future biomarkers of host response and infection, including the microbiome may be useful to guide treatments and to increase the success of randomized trials. Advances in the understanding the inflammatory pathways, microbiome, and genetics in bronchiectasis are key to move towards a personalized medicine in bronchiectasis.

Non-cystic fibrosis bronchiectasis: a retrospective review of clinical, radiological, microbiological and lung function profile at a tertiary care center of low-middle income country

Non-cystic fibrosis (non-CF) bronchiectasis has emerged as a significant respiratory disease in developing countries. Given the variation in causes and clinical characteristics across different regions, it is necessary to conduct studies in regions with limited data such as low-middle income countries (LMIC). The aim of the study was to investigate the underlying causes, clinical presentation, etiology, lung function and imaging in patients with bronchiectasis who sought treatment at a tertiary care hospital in a LMIC. We conducted retrospective observational study at the Aga Khan University, Pakistan. Adult patients diagnosed with non-CF bronchiectasis on high-resolution computed tomography scan between 2000 and 2020 were included. We evaluated the etiology, clinical characteristics, microbiology, radiology and spirometric pattern of these patients. A total of 340 patients were included with 56.5% being female and 44.7% aged over 60 years. Among them, 157 (46.2%) had experienced symptoms for 1-5 years. The most common spirometric pattern observed was obstructive impairment (58.1%). Previous tuberculosis (TB) (52.94%) was the most common etiology followed by allergic bronchopulmonary aspergillosis (7.64%). Bilateral lung involvement on HRCT scan was found in 63.2% of patients. Pseudomonas aeruginosa was the most frequently identified organism (38.75%) among 240 patients with available specimens. Patients with P. aeruginosa infections had a significantly higher number of exacerbations (p=0.016). There was a significant difference (p<0.001) in P. aeruginosa growth among different etiologies. In conclusion, post-TB bronchiectasis was the most common cause of non-CF bronchiectasis in our study population. P. aeruginosa was the predominant organism, and 63.2% of the patients exhibited bilateral lung involvement. Since P. aeruginosa growth and extensive lung involvement have been associated with poor prognosis and increased mortality risk, we recommend close follow ups of these patients to improve quality of life and survival in developing countries like Pakistan.

Health-Related Quality of Life and Stress-Related Disorders in Patients with Bronchiectasis after Pulmonary Resection

This multicenter, cross-sectional study investigates the potential correlation between the development of bronchiectasis after lung resection surgery and the health-related quality of life (HRQoL) of the patients. The study aims to provide new insights into the long-term outcomes of patients post-lung resection surgery. The study includes adult patients who underwent lung resection surgery for suspicious lung nodules and developed bronchiectasis within a follow-up period of six months. Bronchiectasis was confirmed by high-resolution computed tomography scans. The patient's health-related quality of life (HRQoL), anxiety, depression, and stress-related disorders were assessed using WHOQOL-BREF, SF-36, HADS, and PSS-10 questionnaires. Out of the 135 patients included in the study, 44 developed bronchiectasis after lung resection surgery. No statistically significant differences were observed between the groups in terms of demographics and medical history. Patients with bronchiectasis demonstrated a lower overall health status, increased deterioration of respiratory symptoms, lower physical activity levels, lower quality of life scores, and experienced more severe anxiety symptoms. Additionally, patients in this group also perceived higher levels of stress; although, the correlation with physical functioning was contradictory. The development of bronchiectasis post-lung resection surgery was associated with poorer quality of life, increased respiratory symptoms, higher anxiety levels, and increased perception of stress. While the correlation between bronchiectasis and HRQoL was statistically significant, the contradictory correlations with stress and physical functioning call for further research. This study underscores the importance of ongoing patient monitoring and the detailed evaluation of respiratory function following lung resection surgery for lung nodules, especially among those who develop bronchiectasis.

South African Thoracic Society position statement on the management of non-cystic fibrosis bronchiectasis in adults: 2023

Background

Bronchiectasis is a chronic lung disorder that affects the lives of many South Africans. Post-tuberculosis (TB) bronchiectasis is an important complication of previous pulmonary TB and a common cause of bronchiectasis in South Africa (SA). No previous statements on the management of bronchiectasis in SA have been published.

Objectives

To provide a position statement that will act as a template for the management of adult patients with bronchiectasis in SA.

Methods

The South African Thoracic Society appointed an editorial committee to compile a position statement on the management of adult non-cystic fibrosis (CF) bronchiectasis in SA.

Results

A position statement addressing the management of non-CF bronchiectasis in adults in SA was compiled. This position statement covers the epidemiology, aetiology, diagnosis, investigations and various aspects of management of adult patients with non-CF bronchiectasis in SA.

Conclusion

Bronchiectasis has largely been a neglected lung condition, but new research has improved the outlook for patients. Collaboration between interprofessional team members in patient management is important. In SA, more research into the epidemiology of bronchiectasis, especially post-TB bronchiectasis and HIV-associated bronchiectasis, is required.

Abstract

The South African Thoracic Society mandated a multidisciplinary team of healthcare providers to compile a position statement on the management of non-cystic fibrosis bronchiectasis in South Africa (SA). International guidelines on the management of bronchiectasis were reviewed and used as a basis from which the current position statement was compiled. This is the first position statement on the management of adult non-cystic fibrosis bronchiectasis in SA. A description of the epidemiology and aetiology of bronchiectasis is provided, as well as guidance on its diagnosis and management. The position statement provides guidance on the management of bronchiectasis to healthcare providers, policymakers and regulatory authorities.

The Utility of Metagenomic Next-Generation Sequencing (mNGS) in the Management of Patients With Bronchiectasis: A Single-Center Retrospective Study of 93 Cases

Background

Bronchiectasis is a chronic inflammatory respiratory disease mainly caused by pathogenic infections. However, standard methods of pathogen detection show prolonged cycle durations and unsatisfactory sensitivity and detection rates. Macrogenomic next-generation sequencing (mNGS) emerges as a promising technique for swift, effective, and unbiased pathogen detection and subsequent data interpretation.

Methods

Here, a retrospective analysis of 93 patients with suspected bronchiectasis was performed to assess the clinical applicability of mNGS. Bronchoalveolar alveolar lavage fluid (BALF) samples were collected from these subjects, followed by standard assays and mNGS separately. The turnaround time, detection rate, and pathogen identification using mNGS were compared with those of standard methods.

Results

mNGS identified a greater number of bacteria (72 vs 16), fungi (26 vs 19), and viruses (14 vs 0) than standard methods. Specifically, the commonly identified bacteria were Haemophilus, Mycobacterium intracellulare, Pseudomonas, and Streptococcus pneumoniae, while the most detected fungi were Aspergillus and the most prevalent viruses were human herpesviruses. Of note, 29 out of 30 patients (96.67%) who received optimized treatment strategies based on mNGS results experienced recovery.

Conclusions

Collectively, these findings suggest that mNGS has the potential to improve the diagnosis and treatment of bronchiectasis patients by enabling rapid and precise pathogen detection, which can lead to timely and effective treatment strategies.

Hemoptysis as the presenting manifestation of bronchiectasis-associated hospitalization in Korea

BACKGROUND

Patients with bronchiectasis commonly experience disease exacerbations, which cause significant morbidity and mortality. However, data regarding the clinical features of bronchiectasis patients hospitalized with hemoptysis are scarce.

METHODS

We retrospectively collected the data of patients with bronchiectasis-associated hospitalization at a tertiary referral center in Korea, and classified them into the hemoptysis and infective exacerbation (IE) groups. The presence of hemoptysis was defined as a volume of expectorated blood larger than 10 mL per 24 hours. The clinical, radiological, and laboratory parameters were compared between the two groups.

RESULTS

Patients were classified into the hemoptysis [267 (54.5%)] and IE [223 (45.5%)] groups. Among the 44 patients of the hemoptysis group, 37 (84.1%) presented with hemoptysis than with IE at the recurrent episode. The hemoptysis group had a significantly lower 30-day mortality than that of the IE group. Previous pulmonary tuberculosis (TB), mycetoma, and bronchial artery hypertrophy were independently associated with the hemoptysis group. In contrast, male sex, poor performance status, colonization of Pseudomonas aeruginosa, ≥3 involved lobes, cystic bronchiectasis, and emphysema were inversely associated with the hemoptysis group. The absence of hemoptysis was one of the independent predictors of 30-day mortality in patients with bronchiectasis-associated hospitalization.

CONCLUSIONS

In Korea, bronchiectasis patients hospitalized with hemoptysis exhibit a distinct phenotype, and are more likely to have previous pulmonary TB, mycetoma, and bronchial artery hypertrophy. Hemoptysis is associated with a lower risk of short-term mortality compared to IE in bronchiectasis-associated hospitalization.

Etiology and clinical characteristics of a non-cystic fibrosis bronchiectasis cohort in a middle eastern population

BACKGROUND

Bronchiectasis is a widely prevalent airway disease characterized by airway dilatation and recurrent infections, that can lead to respiratory failure in severe cases. The etiology of bronchiectasis varies geographically, but there is a lack of published data examining its etiology specifically within the Middle Eastern population.

METHODS

We conducted a retrospective analysis of our bronchiectasis patient registry, extracting clinical and demographic characteristics from electronic medical records. Quantitative variables were presented as the median and interquartile range (IQR), while categorical variables were expressed as numbers and percentages. Statistical comparisons for continuous characteristics were performed using the t-test, and significance was determined by a p-value less than 0.05.

RESULTS

In total we analysed 260 records (63% female, 37% male), with median age of 58 years (interquartile range (IQR) 38-71), Body Mass Index (BMI) 25.8(IQR 22-30), forced expiratory volume in the first second (FEV1) %predicted 65 (IQR 43-79) and FEV1/forced vital capacity (FVC) 0.76 (0.67-0.86). Sixty-five cases (25%) were post-infectious in aetiology (excluding post-TB - n:27 10.4%). Forty-eight (18.5%) patients were labelled idiopathic, while Primary Ciliary Dyskinesia (PCD) accounted for 23 (8.8%) cases. Pseudomonas aeruginosa was the most common colonizing organism (32.7%), followed by Haemophilus influenzae (9.2%) and Methicillin-Sensitive Staphylococcus aureus(6.9%). At the time of review, 11 patients had died (median age, FEV %predicted, and bronchiectasis severity index (BSI) 59 years, 38% and 15.5 respectively), all due to respiratory failure, and as expected, all were classed severe on BSI. The BSI score was available for 109 patients, of which 31(28%) were classed mild, 29(27%) were moderate, and 49 (45%) were classed severe. The median BSI score was 8 (IQR 4-11). On dividing the patients according to obstructive vs. restrictive spirometry, we found that patients with FEV1/FVC < 0.70 had significantly higher BSI (10.1 vs. 6.9, p-value < 0.001) and that 8 out of the 11 deceased patients had FEV1/FVC < 70%.

CONCLUSIONS

In our study, post-infectious, idiopathic, and PCD were identified as the most common etiologies of bronchiectasis. Additionally, patients with obstructive spirometry appeared to have a worse prognosis compared to those with restrictive spirometry.

Bronchiectasis in Europe: data on disease characteristics from the European Bronchiectasis registry (EMBARC)

BACKGROUND

Bronchiectasis is a heterogeneous, neglected disease with few multicentre studies exploring the causes, severity, microbiology, and treatment of the disease across Europe. This aim of this study was to describe the clinical characteristics of bronchiectasis and compare between different European countries.

METHODS

EMBARC is an international clinical research network for bronchiectasis. We report on a multicentre, prospective, observational, non-interventional, cohort study (the EMBARC registry) conducted across 27 European countries and Israel. Comprehensive clinical data were collected from adult patients (aged ≥18 years) at baseline and annual follow-up visits using electronic case report form. Data from individual countries were grouped into four regions (the UK, northern and western Europe, southern Europe, and central and eastern Europe according to modified EU EuroVoc classification). Follow-up data were used to explore differences in exacerbation frequency between regions using a negative binomial regression model.

FINDINGS

Between Jan 12, 2015, and April 12, 2022, 16 963 individuals were enrolled. Median age was 67 years (IQR 57-74), 10 335 (60·9%) participants were female and 6628 (39·1%) were male. The most common cause of bronchiectasis in all 16 963 participants was post-infective disease in 3600 (21·2%); 6466 individuals (38·1%) were classified as idiopathic. Individuals with bronchiectasis experienced a median of two exacerbations (IQR 1-4) per year and 4483 (26·4%) patients had a hospitalisation for exacerbation in the previous year. When examining the percentage of all isolated bacteria, marked differences in microbiology were seen between countries, with a higher frequency of Pseudomonas aeruginosa and lower Haemophilus influenzae frequency in southern Europe, compared with higher H influenzae in the UK and northern and western Europe. Compared with other regions, patients in central and eastern Europe had more severe bronchiectasis measured by the Bronchiectasis Severity Index (51·3% vs 35·1% in the overall cohort) and more exacerbations leading to hospitalisations (57·9% vs 26·4% in the overall cohort). Overall, patients in central and eastern Europe had an increased frequency of exacerbations (adjusted rate ratio [RR] 1·12, 95% CI 1·01-1·25) and a higher frequency of exacerbations leading to hospitalisations (adjusted RR 1·71, 1·44-2·02) compared with patients in other regions. Treatment of bronchiectasis was highly heterogeneous between regions.

INTERPRETATION

Bronchiectasis shows important geographical variation in causes, microbiology, severity, and outcomes across Europe.

FUNDING

European Union-European Federation of Pharmaceutical Industries and Associations Innovative Medicines Initiative.

TRANSLATIONS

For the Arabic, French, German, Greek, Hebrew, Irish, Russian and Spanish translations of the abstract see Supplementary Materials section.

Tuberculosis in older adults: challenges and best practices in the Western Pacific Region

The Western Pacific has one of the fastest-growing older adult populations globally, and tuberculosis (TB) remains one of the foremost infectious causes of disease and death in the region. Older adults are at higher risk of TB due to immunosenescence, comorbidities, and increased institutionalisation. Atypical symptoms and reduced access to health services may delay care-seeking and TB diagnosis, while co-morbidity and increased risk of adverse drug reactions complicate TB treatment. Post-TB sequelae and socioeconomic challenges may decrease the quality of life after TB treatment completion. Despite their high disease burden and special challenges, there is a lack of regionally coordinated policies and guidelines to manage TB among older adults. Routine TB screening at aged-care facilities, age-friendly infrastructure and services, awareness of atypical TB features, integration of TB and non-communicable diseases services, and person-centred approaches to treatment support could improve TB management among older adults. Addressing these challenges and adopting the best practices identified should inform policy formulation and implementation.

Funding

This project was funded by 1) the World Health Organization Regional Office for the Western Pacific, with financial contributions from the Government of the Republic of Korea through the Korean Disease Control and Prevention Agency and the Government of Japan through the Ministry of Health, Labour and Welfare, and 2) NUS Start-up Grant. The funders had no role in the paper design, collection, analysis, and interpretation of data and in writing of the paper.

A Phase 2 randomised study to establish efficacy, safety and dosing of a novel oral cathepsin C inhibitor, BI 1291583, in adults with bronchiectasis: Airleaf

New therapies are needed to prevent exacerbations, improve quality of life and slow disease progression in bronchiectasis. Inhibition of cathepsin C (CatC) activity has the potential to decrease activation of neutrophil-derived serine proteases in patients with bronchiectasis, thereby reducing airway inflammation, improving symptoms, reducing exacerbations and preventing further airway damage. Here we present the design of a phase 2 trial (Airleaf™; NCT05238675) assessing the efficacy and safety of a novel CatC inhibitor, BI 1291583, in adult patients with bronchiectasis. This multinational, randomised, double-blind, placebo-controlled, parallel-group, dose-finding study has a screening period of at least 6 weeks, a treatment period of 24-48 weeks and a follow-up period of 4 weeks. ∼240 adults with bronchiectasis of multiple aetiologies will be randomised to placebo once daily, or BI 1291583 1 mg once daily, 2.5 mg once daily or 5 mg once daily in a 2:1:1:2 ratio, stratified by Pseudomonas aeruginosa infection and maintenance use of macrolides. The primary efficacy objective is to evaluate the dose-response relationship for the three oral doses of BI 1291583 versus placebo on time to first pulmonary exacerbation up to Week 48 (the primary end-point). Efficacy will be assessed using exacerbations, patient-reported outcomes, measures of symptoms, sputum neutrophil elastase activity and pulmonary function testing. Safety assessment will include adverse event reporting, physical examination, monitoring of vital signs, safety laboratory parameters, 12-lead electrocardiogram, and periodontal and dermatological assessments. If efficacy and safety are demonstrated, results will support further investigation of BI 1291583 in phase 3 trials.

Evaluation of metagenomic next-generation sequencing diagnosis for invasive pulmonary aspergillosis in immunocompromised and immunocompetent patients

BACKGROUND

Invasive pulmonary aspergillosis (IPA) can occur in both immunocompromised and non-immunocompromised hosts, and early diagnosis of IPA is difficult. Metagenomic next-generation sequencing (mNGS) is a novel non-migratory pathogen detection method; however, utilising this method for IPA diagnosis is challenging due to the current lack of a unified clinical interpretation standard following Aspergillus detection using mNGS.

OBJECTIVES

To investigate the accuracy of IPA diagnosis by positive bronchoalveolar lavage fluid (BALF) mNGS results in immunocompromised and immunocompetent patients.

METHODS

We retrospectively included patients with confirmed pulmonary infections having a BALF mNGS result of Aspergillus reads ≥1. We compared the accuracy of using mNGS for IPA diagnosis in patients with different immune statuses based on the revised EORTC/MSG criteria.

RESULTS

Overall, 62 mNGS Aspergillus-positive patients were divided into two groups: with (41) and without IPA (21). In univariate logistic regression analysis, immunocompromised function, fever, halo sign on CT image, and multiple masses or nodules were associated with mNGS Aspergillus-positive IPA diagnosis. In multivariate logistic regression analysis, immunocompromised function (OR = 6.68, 95% CI: 1.73-25.87, p = .006) and a halo sign (OR = 7.993, 95% CI: 2.07-30.40, p = .003) were independent risk factors. The concordance rate of IPA diagnosis was significantly higher in immunocompromised patients [82.1% (23/28)] than in non-immunocompromised patients [52.9% (18/34); p = .016].

CONCLUSIONS

For immunocompromised patients, a combination of mNGS testing and lung CT imaging can be used for IPA diagnosis. However, caution is required in IPA diagnosis based on positive mNGS results in non-immunocompromised patients.

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.

Clinical, Radiological, and Lung Function Characteristics of Post-tuberculosis Bronchiectasis: An Experience From a Tertiary Care Center in India

Introduction Among chronic respiratory diseases, bronchiectasis is one of the important causes of mortality and morbidity in developing countries. Objective This study aimed to assess the clinical, radiological, microbiological, and pulmonary function profiles of adult patients with post-tubercular bronchiectasis. Methods We enrolled 138 patients with bronchiectasis confirmed by high-resolution CT scans from July 2017 to August 2018. Results A total of 138 patients with bronchiectasis were enrolled. The data from 132 patients were analyzed; six patients were excluded from the study. The mean age of post-TB bronchiectasis (post-tuberculosis bronchiectasis) patients was 36.08±13.08, which was lower than the non-tuberculosis bronchiectasis group. The proportion of the male population was more in the post-TB bronchiectasis group (54.55% vs. 37.88%, p=0.48). Smoking prevalence was high in post-TB bronchiectasis (27.27% vs. 12.12%, p=0.04). The predominant symptom was cough in the post-tubercular bronchiectasis group (48.5% vs. 41.7%, p=0.019). The history of the recurrent common cold was seen most frequently in non-post-tubercular bronchiectasis (40.9% vs. 12.9%, p=0.001). The most common radiological variant of bronchiectasis found in all patients was a cystic type (75%). The most common site of involvement was the left lower lobe, followed by the lingula in all patients and post-tuberculosis bronchiectasis patients. Pulmonary function on spirometry revealed obstructive, restrictive, and mixed patterns in 55%, 25%, and 15%, respectively. Patients with post-tuberculosis bronchiectasis had lower lung function post-FEV1/FVC (forced expiratory volume in one second/forced vital capacity) ratio (70.31±15.56 vs. 76.85±11.82, p=0.015). Binary multivariate logistic regression analysis showed that only recurrent cough cold was a significant independent risk factor for post-TB bronchiectasis. Conclusion Post-tuberculosis, and bronchiectasis followed by post-infectious causes, were the most common causes of bronchiectasis and poor lung function.

Insights into Personalised Medicine in Bronchiectasis

Bronchiectasis is a heterogenous disease with multiple aetiologies resulting in inflammation and dilatation of the airways with associated mucus production and chronic respiratory infection. The condition is being recognised ever more frequently as the availability of computed tomography increases. It is associated with significant morbidity and healthcare-related costs. With new understanding of the disease process, varying endotypes, identification of underlying causes and treatable traits, the management of bronchiectasis can be increasingly personalised.

A Scoring System Based on Laboratory Parameters and Clinical Features to Predict Unfavorable Treatment Outcomes in Multidrug- and Rifampicin-Resistant Tuberculosis Patients

Background

The growth of antibiotic resistance to Mycobacterium TB represents a major barrier to the goal of "Ending the global TB epidemics". This study aimed to develop and validate a simple clinical scoring system to predict the unfavorable treatment outcomes (UTO) in multidrug- and rifampicin-resistant tuberculosis (MDR/RR-TB) patients.

Methods

A total of 333 MDR/RR-TB patients were recruited retrospectively. The clinical, radiological and laboratory features were gathered and selected by lasso regression. These variables with area under the receiver operating characteristic curve (AUC)>0.6 were subsequently submitted to multivariate logistic analysis. The binomial logistic model was used for establishing a scoring system based on the nomogram at the training set (N = 241). Then, another independent set was used to validate the scoring system (N = 92).

Results

The new scoring system consists of age (8 points), education level (10 points), bronchiectasis (4 points), red blood cell distribution width-coefficient of variation (RDW-CV) (7 points), international normalized ratio (INR) (7 points), albumin to globulin ratio (AGR) (5 points), and C-reactive protein to prealbumin ratio (CPR) (6 points). The scoring system identifying UTO has a discriminatory power of 0.887 (95% CI=0.835-0.939) in the training set, and 0.805 (95% CI=0.714-0.896) in the validation set. In addition, the scoring system is used exclusively to predict the death of MDR/RR-TB and has shown excellent performance in both training and validation sets, with AUC of 0.930 (95% CI=0.872-0.989) and 0.872 (95% CI=0.778-0.967), respectively.

Conclusion

This novel scoring system based on seven accessible predictors has exhibited good predictive performance in predicting UTO, especially in predicting death risk.

Clinical outcomes of bronchiectasis in India: data from the EMBARC/Respiratory Research Network of India registry

BACKGROUND

Identifying risk factors for poor outcomes can help with risk stratification and targeting of treatment. Risk factors for mortality and exacerbations have been identified in bronchiectasis but have been almost exclusively studied in European and North American populations. This study investigated the risk factors for poor outcome in a large population of bronchiectasis patients enrolled in India.

METHODS

The European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) and Respiratory Research Network of India (EMBARC-India) registry is a prospective observational study of adults with computed tomography-confirmed bronchiectasis enrolled at 31 sites across India. Baseline characteristics of patients were used to investigate associations with key clinical outcomes: mortality, severe exacerbations requiring hospital admission, overall exacerbation frequency and decline in forced expiratory volume in 1 s.

RESULTS

1018 patients with at least 12-month follow-up data were enrolled in the follow-up study. Frequent exacerbations (≥3 per year) at baseline were associated with an increased risk of mortality (hazard ratio (HR) 3.23, 95% CI 1.39-7.50), severe exacerbations (HR 2.71, 95% CI 1.92-3.83), future exacerbations (incidence rate ratio (IRR) 3.08, 95% CI 2.36-4.01) and lung function decline. Coexisting COPD, dyspnoea and current cigarette smoking were similarly associated with a worse outcome across all end-points studied. Additional predictors of mortality and severe exacerbations were increasing age and cardiovascular comorbidity. Infection with Gram-negative pathogens (predominantly Klebsiella pneumoniae) was independently associated with increased mortality (HR 3.13, 95% CI 1.62-6.06), while Pseudomonas aeruginosa infection was associated with severe exacerbations (HR 1.41, 95% CI 1.01-1.97) and overall exacerbation rate (IRR 1.47, 95% CI 1.13-1.91).

CONCLUSIONS

This study identifies risk factors for morbidity and mortality among bronchiectasis patients in India. Identification of these risk factors may support treatment approaches optimised to an Asian setting.