The airway microbiota in children newly diagnosed with bronchiectasis largely retains its diversityTo the Editor:There is a great deal of interest in the airway microbiota, its diversity and the role of specific microbial taxa in the pathophysiology of lung disease [1]. Non-cystic fibrosis bronchiectasis is a significant public health problem in many countries, including New Zealand, where prevalence is high and morbidity and mortality are substantial [2][3][4]. A role for bacteria in the pathophysiology of bronchiectasis is widely accepted but poorly characterised due to inherent difficulties with lower airway sampling, especially in young children. Culture-based studies demonstrate associations with Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae in children [2,5], and Pseudomonas aeruginosa in adults and those with severe disease [6,7]. Culture-independent methods have revealed complex airway microbial communities with differences between children and adults with bronchiectasis, and between adults with cystic fibrosis and bronchiectasis [8]. A shared core microbiota was reported for children with bronchiectasis, protracted bacterial bronchitis (PBB) and cystic fibrosis, with most of these taxa also seen in healthy controls [8]. Subsequent research indicated that microbiota composition could be used to distinguish bronchiectasis, PBB and control children [9]. In children with PBB, bronchial brush samples were dominated by Haemophilus, Moraxella, Streptococcus and Neisseria [10], while bronchoalveolar lavage (BAL) samples showed that Bacteroides and Haemophilus were more common than in disease controls, with Lactococcus and Lactobacillus less common [11]. Differences in study findings could be due to methodological differences, disease heterogeneity and timing of airway samples. Adults with bronchiectasis demonstrate a dominance of either Haemophilus or Pseudomonas. Pseudomonal dominance is associated with end-stage lung disease and potentially adverse clinical outcomes [6,7]. Recent longitudinal studies in children with cystic fibrosis demonstrate a reduction in microbial diversity with age, with establishment of more traditional disease-modifying taxa [12]. An emerging common theme is that reduced microbiota diversity, and certain bacterial taxa, may potentially be associated with adverse clinical outcomes.We undertook a prospective study at Starship Children's Hospital, Auckland, New Zealand between 2015 and 2017, enrolling children being investigated for bronchiectasis as per our regional guidelines [13]. Flexible bronchoscopic BAL (1 mL•kg −1 lavage of 0.9% saline, maximum 20 mL) was performed from the 2-3 most affected lobes in children with bronchiectasis as identified by chest computed tomography (CT) scan. Bronchiectasis was radiologically defined as a broncho-arterial ratio of more than 1.0 in combination with other well-described radiological features [2,14]. We also recruited controls undergoing elective surgery, with no respiratory history. A single non-bronchoscopic lavag...

The goals of asthma management are accurate diagnosis, prompt initiation of treatment and monitoring of disease progression to limit potential morbidity and mortality. While the diagnosis and management is largely based on history taking and clinical examination, there are an increasing number of tools available that could be used to aid diagnosis, define phenotypes, monitor progress and assess response to treatment. Tools such as the Asthma Predictive Index could help in making predictions about the possibility of asthma in childhood based on certain clinical parameters in pre-schoolers. Lung function measurements such as peak expiratory flow, spirometry, bronchodilator responsiveness, and bronchial provocation tests help establish airway obstruction and variability over time. Tools such as asthma questionnaires, lung function measurements and markers of airway inflammation could be used in combination with clinical assessments to assess ongoing asthma control. Recent advances in digital technology, which open up new frontiers in asthma management, need to be evaluated and embraced if proven to be of value. This review summarises the role of currently available tools in asthma diagnosis and management. While many of the tools are readily available in resource rich settings, it becomes more challenging when working in resource poor settings. A rational approach to the use of these tools is recommended.

IntroductionNon-cystic fibrosis bronchiectasis is a respiratory health condition with many possible aetiologies, some of which are potentially reversible in childhood with early diagnosis and appropriate treatment. It is important to understand factors which contribute to progression or potential resolution of bronchiectasis. It is evident that respiratory exacerbations are a key feature of bronchiectasis disease progression. In this pilot study we document how the microbiota of the upper and lower airways presents during the course of an exacerbation and treatment.MethodsWe recruited children (aged 1-15) undergoing antibiotic treatment for bronchiectasis exacerbations at Starship Children’s Hospital and outpatient clinics. Sputum and nasal swabs were taken before and after antibiotic treatment. Sample DNA was extracted, then bacterial 16S rRNA genes amplified and sequenced via Illumina MiSeq.ResultsThirty patients were recruited into this study with 81 samples contributing to the final dataset, including 8 patients with complete sets of upper and lower airway samples at both (before and after antibiotics) timepoints. Changes in alpha-diversity over the course of an exacerbation and treatment were non-significant. However, sample composition did alter over the course of an exacerbation, with most notably a reduction in the relative abundance of amplicon sequence variants assigned to Haemophilus.DiscussionHaemophilus has been associated with more severe symptoms in respiratory infections and a reduction in its relative abundance may represent a positive shift in a patient’s microbiota. Current treatments for bronchiectasis may preserve bacterial diversity while altering microbiota composition.

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