What is bronchiectasis?

Bronchiectasis is a lung disease that occurs when the walls of the breathing tubes or airways widen due to chronic inflammation and/or infection. Normally, tiny glands in the lining of the airways make a small amount of mucus. Mucus keeps the airways moist and traps any dust and dirt in the inhaled air. Because bronchiectasis creates an abnormal widening of the airways, extra mucus tends to form and pool in parts of the widened airways. Widened airways with extra mucus are prone to recurrent respiratory tract infection (WHO 2020).

The signs and symptoms of bronchiectasis can take months or even years to develop. The most common signs and symptoms of bronchiectasis include long-term cough, increased mucus production, shortness of breath, feeling tired, weight loss, wheezing or whistling sounds with breathing, chest pain, and coughing up blood (Lung Foundation Australia 2020). The symptoms, severity and disease course of bronchiectasis may vary. Bronchiectasis may also cause long term disability, accelerated lung function loss and premature death in adults (Loebinger et al. 2009).

The clinical symptoms of bronchiectasis and asthma may overlap significantly as symptoms of cough, sputum and dyspnoea can occur in either asthma or bronchiectasis (Kang et al. 2014). In addition, bronchiectasis and chronic obstructive pulmonary disease (COPD) also share common symptoms of cough with sputum production and susceptibility to recurrent exacerbations (Hurst et al. 2015). Although these three diseases present several common characteristics, they have different clinical outcomes. Therefore, it is important to differentiate them at early stages of diagnosis, so appropriate therapeutic measures can be adopted (Athanazio 2012). For more information, see Asthma and Chronic obstructive pulmonary disease (COPD).

What causes bronchiectasis?

The cause of bronchiectasis is often not clear. Some conditions known to cause bronchiectasis that affect or damage airways are:

  • Immunodeficiency which predisposes the person to lung infections. This can be primary (inherited cause) or secondary (related to chemotherapy) (King 2009).
  • Untreated low grade infection of the airways (Pragman et al. 2016).
  • Lung infections that cause the damage to the walls of the airways, such as tuberculosis (TB), whooping cough, measles, pneumonia, or fungal infections, particularly in childhood. Bronchiectasis may then develop.
  • Conditions that damage the airways and raise the risk of lung infections. For example, cystic fibrosis (CF), which is a hereditary disease that can cause thick, sticky mucus to build up in the lungs. Allergic bronchopulmonary aspergillosis (ABPA), which causes airway swelling, is another condition that can affect the lung and cause bronchiectasis.
  • Conditions that cause an airway blockage, such as a growth or a noncancerous tumour, regurgitated stomach acid, or inhaled objects that become stuck and block an airway (WHO 2020).

Who gets bronchiectasis?

Bronchiectasis can affect anyone at any age, and in any socioeconomic group, but the disease occurs much more commonly in rural and remote Indigenous communities and in less affluent communities (Chang et al. 2003; Karadag et al. 2005; Singleton et al. 2000; Twiss et al. 2005). This may be due to limited access to quality health services, non-adherence to medications and inadequate medical follow-up (Goeminne & Dupont 2010). In addition, studies based in the United Kingdom and the United States have found females and the elderly are more frequently affected (Seitz et al. 2012; Quint et al. 2016).

Although increasingly recognised, there is little information available on the prevalence or incidence of bronchiectasis in Australia. The only available Australian data on bronchiectasis is in children aged under 15 years. A study of Central Australian Aboriginal children found the prevalence of non-cystic fibrosis bronchiectasis among Aboriginal children aged under or equal to 15 years was at least 1,470 per 100,000 population (Chang et al. 2003).

The Australian Bronchiectasis Registry (commenced in 2015) will facilitate more accurate estimates of bronchiectasis in Australia in the future. It is a non-commercial research project that has been initiated by a group of Australian Respiratory Specialist doctors together with The Lung Foundation Australia. The main aims of this registry are to identify and collect health information from patients with non-Cystic Fibrosis (non-CF) Bronchiectasis for doctors to research the causes and to improve treatments. For more information visit The Lung Foundation of Australia.