Introduction and Aeitology
This is a disease that causes local irreversible dilation of the bronchial tree.
It is an obstructive lung disease.
It is almost always a result of bronchial obstruction leading to infection with inflammation (distal to the obstruction)
In the UK, you are probably most likely to see it as a result of CF.
Bronchiectasis is not really a disease in itself, it is more a complication of other conditions. For example, things that can cause bronchiectasis include:
- Cystic fibrosis – the most common cause in developed countries
- Bordetella pertussis infections (Whooping Cough) can sometimes cause bronchiectasis later in life
- Ciliary dysfunction syndromes
- Primary hypogammaglobuminaemia
- Congenital abnormalities (usually rare ones)
- TB – this is the most common cause worldwide
It can be acquired (e.g. TB) or congenital (e.g. CF)
- Chronic cough
- Production of large amounts of foul smelling sputum, which may also contain flecks of blood
- The cough is usually worse in the mornings, and may be brought on by changes in posture
- Finger clubbing may be present
- Recurrent RTI’s, as the patient is unable to clear the pooled secretions that collect
- Fever and malaise – as a result of recurrent (and perhaps ever-present) infection.
- Haemoptysis – may just be flecks of the sputum, but in ‘dry bronchiectasis’ it may be the only symptom.
In advanced disease, there is a general decline in health; probably include; weight loss, anorexia, low-grade fever, and failure to thrive (children). It is in these patients that clubbing is common – i.e. clubbing is late to show itself.
May be unilateral or bilateral.
- Coarse crackles (numerous) over areas containing large amounts of sputum
- Possible collapse (no breath sounds)
- Reduced or absent breath sounds at areas distal to places of obstruction
There will be destruction of the alveolar walls (and the elastin contained in them), with fibrosing of the remaining parenchyma. It can be caused by an obstruction by something as simple as a peanut. The airway will then dilate as the surrounding scar tissue contracts. This can in itself cause secondary inflammatory changes which leads to further destruction of the airways.
Usually the lower lobes are most greatly affected. This can lead to pooling of bronchial secretions, which increases the risk of further infections in this area. There will often also be collections of pus.
The mucociliary transport system is also often damaged.
- Sputum sample! – you may find pseudomonas aeruginosa, H influenzae, staph aureus, aspergillus fumigates, fungi (e.g. Aspergillus) and various mycobacteria
- CXR – In most cases, this will be normal, unless the bronchiectasis is widespread. In advanced disease you may be able to see areas of thickened airway walls, cystic spaces, and consolidation or collapse.
- CT – much more sensitive than CXR, and shows thickened and dilated airways, and the classic signet ring appearance
- Genotyping – if the cause is a genetic disorder (CF) you may want to genotype(also if you don’t know the cause you could do this if you suspect CF) – however this is a very poor predictor of prognosis. For example, twins with the same genotype, may have a very different phenotype
- Sweat electrolyte testing –if you suspect CF
- Measure mucociliary clearance –you put a 1mm cube of saccharin on the inferior nasal concha and measure the time taken to taste it. This should be less than 30 minutes in a normal individual. If longer it could be a result of excess mucous production (CF)
Note that the management of bronchiectasis is the same as the management of CF!
Treatment is not curative. It is aimed at reducing the risk of infections, reducing bronchial secretions, and preventing complications.
- Postural drainage – this is essential! Patients should be trained by physiotherapists in how to tip themselves into a position in which the affected lobe(s) is drained in an uppermost direction at least 3 times a day for 10-20 minutes – most patients find the most effective position is to lie down over the side of the bed with the head and thorax down
- Antibiotics – to halt progression of the disease you need to give adequate antibiotic therapy. This obviously depends on the infective organism:
- Initially, try a broad spectrum, such as cefaclor or ciprofloxacin.
- Try flucloxacillin 500mg every 6 hours if this fails. This is to treat staph aureus.
- If the sputum remains yellow or green after regular phsyio and other AB’s, then it is likely the infective organism is P aeruginosa. This probably required inhaled AB’s, such as ceftazidime (which can also be given IV). You could also try inhaled cipro, but this creates resistance quickly.
- Steroids – can slow down the rate of progression of the disease
- Bronchodilators – may be of use to patients with airflow limitation
- Surgery – this is rare because it is unlikely the bronchiectasis is confined to a small enough area such that adequate lung function would be available after the operation
- Pulmonary fibrosis
- Cor pulmonale
- Metastatic abscesses e.g. in the brain– due to the continued presence of infection
- Amyloid formation
- Amyloid plaques are insoluble fibrous protein aggregates. Their accumulation can lead to amyloidosis. A protein as described as being amyloid if it has a slightly altered structure, making it insoluble.
- Amyloidosis can occur in many organs, and the symptoms vary greatly from organ to organ
- Massive haemoptysis – this can result from the high pressure found in arteries in the condition. Treatment for this would probably only consist of bed rest and antibiotics until the bleeding stops. Blood transfusion is given if required
This has greatly improved with antibiotic therapy. Ultimately, many patients die from respiratory failure due to deterioration of the lung tissue. Cor pulmonale is also common.