What is bronchiectasis?
Bronchiectasis is an abnormal increase in the size of the bronchi, which are the tubes that take air into the lung. Having big and baggy bronchi means that bacteria get caught in these tubes much more easily than they can in the normal narrow bronchi.
As a result, patients with bronchiectasis often have chronically infected bronchi, and this is what causes most of the symptoms. The severity of bronchiectasis varies a lot between patients; some patients will only have mild disease and only know they have bronchiectasis as they require antibiotics for a chest infection once a year or so; others have severe disease which means they have to take antibiotics all the time and may even have problems with their breathing due to the chronic lung damage. Most patients with bronchiectasis are somewhere between these two extremes.
What causes bronchiectasis?
The commonest causes of bronchiectasis are:
- Idiopathic (about 50% of patients); that is, we do not know why these patients have bronchiectasis. The presumption is that these patients have relatively minor defects in their ability to clear the lungs of infection, allowing bacteria to stay in the bronchi and cause damage. But we do not know for sure and so one important area of research is to work out why these patients develop bronchiectasis.
- Post-lung infection. Childhood (and sometimes adult) lung infections such as tuberculosis, measles, whooping cough and pneumonia can leave behind areas of damaged lung with bronchiectasis.
- Immune defects. Patients with low antibody levels or other problems with the immune system suffer from recurrent lung infections, which can lead to bronchiectasis.
- Cystic fibrosis and ciliary dyskinesia. These are rare inherited genetic diseases in which the bronchi are unable to clear bacteria and the chronic infection results in bronchiectasis.
- Allergic bronchopulmonary aspergillosis (ABPA). Patients with ABPA have developed an allergy to a fungus called Aspergillus. We all breathe in spores of Aspergillus every day, and these inflame the lungs of patients who have the allergy to the fungus, damaging the bronchi and resulting in bronchiectasis.
- Rheumatoid arthritis. Many patients with rheumatoid arthritis will also develop lung damage including bronchiectasis, probably as the inflammation caused by the rheumatoid arthritis also affects the lung.
In addition, there are a large number of rare causes of bronchiectasis.
How is bronchiectasis diagnosed?
Bronchiectasis is usually diagnosed using a detailed X-ray of the lungs called a CT scan. A standard chest X ray is often normal or near normal in patients with bronchiectasis, and even when abnormal, the changes that are present may not be obviously due to bronchiectasis. Blood tests are required to test for some of the causes of bronchiectasis and it is also important to measure the lung size and function by a simple breathing test called spirometry.
Can bronchiectasis be treated?
Once bronchiectasis has developed, the damage cannot be reversed. However, in most patients, the disease either does not worsen or only slowly worsens with time, and the combination of regular physiotherapy to clear the chest and appropriate antibiotics control the symptoms reasonably well. It is vital that chest infections are treated quickly with effective antibiotics for at least 10 to 14 days. Using a more prolonged course of antibiotics is important to prevent the chest infections recurring quickly, and often patients need treatment with antibiotics that can kill more resistant organisms such as coamoxiclav 625mg tds. Some patients with frequent chest infections requiring antibiotics several times per year will need to start low dose antibiotics all the time to prevent infections. Characterising exactly what happens during an exacerbation of bronchiectasis and investigating the best long term treatments are other important areas for research.
Living with bronchiectasis
The most important considerations for patients with bronchiectasis are the following:
- They need to perform regular lung clearance techniques to prevent phlegm and bacteria accumulating in the lungs. In many patients, this will probably need to be done once or twice a day.
- When an infection develops, the patient needs to start antibiotics as quickly as possible as this allows the infection to be brought under control more rapidly than if the antibiotics are delayed. Most patients should therefore have a reserve course of antibiotics at home. And it is important that the antibiotics are taken for 10 to 14 days to ensure the infection is well-controlled and less likely to return when the antibiotics are stopped.
- To help prevent infections, the patients should be vaccinated once against pneumonia and have an annual vaccination against flu. And they should never smoke cigarettes.
- Some patients may need to take inhalers, nebulisers or continual low dose antibiotics as well.
Ongoing research at UCL Respiratory
For many years, the disease of bronchiectasis has not received the attention it deserves, considering that our research (Quint et al. European Respiratory Journal, 2015) shows that maybe 100,000 people in the UK with the condition. There has been so little research into bronchiectasis that even the most basic questions about why patients get chest infections (called exacerbations) are not really known, and there are many questions about the best long term treatments that still need answering.
At UCL, we have an established programme of research into lung infections, which investigates patients with bronchiectasis in collaboration with our partners within University College London, Royal Free and Whittington Hospitals. This collaboration has resulted in several research papers describing in detail the changes in clinical condition that occur in a patient with bronchiectasis who is having an infective exacerbation, how common bronchiectasis is, and demonstrating that bronchiectasis is associated with an increased risk of diseases affecting the blood vessels, such as strokes and heart attacks. In addition, we are members of the Bronch UK partnership of nine centres across the UK who are collaborating into research into different aspects of bronchiectasis. We are researching why patients with bronchiectasis develop exacerbations of their condition, and what are the best ways to prevent these exacerbations occurring. These research programmes do require financial resources in order to pay for the various laboratory tests necessary – we hope that by using relatively small amounts of money to fund initial research, we will obtain the background data needed to successfully apply for large grants to fully answer some of the important questions about how best to treat patients with bronchiectasis.