Moving forward: Bronchiectasis and chronic suppurative lung disease in children and adults in the 21st century

Bronchiectasis, still considered an ‘orphan disease’ by some, is now recognized as a major cause of chronic respiratory disease in children and adults in the 21st century.1 In the past decades, bronchiectasis and chronic suppurative lung disease (CSLD) were recognized as being particularly prevalent only among indigenous populations of affluent countries.2, 3 Now, with the increasing recognition among mainstream adults in our current era, there is a substantial forward movement in therapeutics4 and pathological studies as well as pharmaceutical interest. This series of articles focusing on bronchiectasis is timely, authored by global experts in the field and uniquely includes perspectives on both children’s and adults’ diseases. The series begins with aspects relating to diagnosis, burden of disease and prognosis, and concludes with the importance and role of multidisciplinary teams and self-management plans.

The substantial advances in this field will be highlighted in this series of articles that have a clinical slant to match the journal’s readership. Advances in clinical care include position statements, guidelines and standards of care.5 The first, published in 2002,6 was then followed by others in affluent7 and less affluent countries8 reflecting the increasing appreciation of the disease, although there remains a dearth of randomized controlled trials. The aspects of various treatment modalities including prevention and emerging therapies will be unravelled in this series.

Bronchiectasis is a heterogeneous condition with multiple underlying aetiologies, coexisting diseases and overlap syndromes.9, 10 International experts will provide state-of-the-art insight. However, there remains a large group of patients with bronchiectasis where no underlying aetiology can be defined. One challenge in our era of personalized medicine, endotypes and phenotypes of diseases is to develop objective characterization of how best to classify children and adults with bronchiectasis.

Another challenge is the prevention of CSLD and bronchiectasis and/or its progression. While the clinical challenge in adults often focuses on symptom control and prevention of hospitalization, in children, the focus is on reversing the disease when possible and halting the progress. The reversibility of radiologically defined bronchiectasis is possible when the cylindrical bronchiectasis is treated early in children. This is sometimes a distant concept among adult physicians and in contrast to the definition of ‘irreversibility’, defined before computed tomography (CT) scans were available. Astute paediatricians recognized more than half a century ago that bronchiectasis can be prevented and reversed11-13 at least in a substantial proportion and that untreated persistent lower airway infection (manifested by chronic wet cough14) leads to chronic lung disease. The duration of chronic cough correlates to poorer lung function and worse radiology bronchiectasis scores in children and adults.15, 16 This is highlighted by study describing that 80% of the 107 non-indigenous Australian adults with bronchiectasis had chronic cough from childhood/adolescents.15 Those who were symptomatic from childhood had significantly worse disease (CT radiology scores, lung function, more exacerbations and hospitalizations).15

Prevention requires a multidisciplinary approach starting from foetal well-being and early childhood. Early diagnosis (and subsequent management) is required to break the cycle of infection and inflammation17 and requires alert clinicians (physicians, nurses and physiotherapists) as bronchiectasis is dependent on case ascertainment. Appropriate investigations in patients who have chronic wet or productive cough are required. Adults’ studies have shown that multi-detector CT scans are more sensitive than conventional HRCT in detecting bronchiectasis.18, 19 In children, there are calls to use a different radiological cut-off20, 21 in the awareness that the bronchoarterial ratio (a key component of radiological diagnosis of bronchiectasis) significantly correlates with age (r = 0.768, P < 0.0001) in individuals without cardiopulmonary illness.22

With increasing clinical and research interests in bronchiectasis, we now look forward to advancing this relatively poorly resourced and researched condition. Innovations include new national registries for bronchiectasis, definitions of exacerbations23, 24 and statements of standards of care5 and various severity and prognostic scores for adults (e.g. bronchiectasis severity index25 and Bronchiectasis Radiologically Indexed CT Score26).

We thank the authors of each of these reviews for sharing expertise and enlightening the readers. This series of articles will hopefully stimulate improved clinical awareness (hence earlier diagnosis and better management to improve lives of patients) as well as interest in research in this increasing appreciated but still neglected field of respiratory medicine.

Disclosure statement

Professor A.B.C. is supported by an Australian National Health and Medical Research Council (NHMRC) Practitioner Fellowship (Grant APP1058213) and has received multiple grants from the NHMRC relating to this subject matter. Professor A.T.H. has been on advisory boards for Bayer.