What is Asbestosis?

Asbestosis is a chronic fibrotic interstitial lung disease which is asbestos-induced. It is a non-cancerous condition. Fibrosis is a scarring of the lung. Interstitial refers to the lung tissue itself. In asbestosis it is the lung tissue, not the airways, that is damaged. The scarring results from asbestos fibres penetrating the lung tissue and causing inflammation. When this process continues then further scarring results. The alveoli (air sacks), where oxygen exchange occurs and oxygen diffuses into the blood stream, become scarred, damaged and obliterated. The scarring or fibrotic change within the’ lung tissue causes the lungs to be stiff and hence it is more difficult to breathe. The lung becomes very inelastic; hence the lung does not exchange oxygen and C02 adequately because eventually the alveolar gas exchange units are markedly reduced in number and function. Dyspnoea or shortness of breath on exertion is one of the symptoms of asbestosis.

xrayFibrotic changes in the lungs can be associated with various causes other than asbestos such as silica dust, animal dust exposure, rheumatoid arthritis and many other causes. Exposure to silica dust, for instance arising from excavation work in rock with high silica content, can cause silicosis. Exposure to dusts from various birds can cause a fibrotic condition in the lung known as “birds fanciers’ lung”.

However, asbestosis refers exclusively to asbestos-induced fibrosis of the lung. Asbestosis is usually diffuse in that it is usually found throughout the lower sections of both of the lungs, and not isolated. The fibrosis associated with asbestosis is often roughly equal in both lungs. As the disease progresses, the upper lobes may be affected.

Symptoms of Asbestosis

asbestosisAsbestosis is usually a progressive disorder. Exertional breathlessness gradually worsens often over a period of years. As asbestosis progresses the scarring causes the lung to shrink and breathing becomes more difficult.

The damage to the lungs’ capacity may not be detected for many years due to the lungs’ reserve. As the disease progresses lung capacity reduces. Patients who suffer from asbestosis have an increased risk of developing bronchitis, pneumonia and heart disease. As a consequence asbestosis sufferers may present with heart-related symptoms such as abnormal heart rhythm and  heart failure.

As well as arising from causes other than asbestos exposure interstitial fibrosis may also be idiopathic, meaning that no cause can be determined.  This condition is known as idiopathic pulmonary fibrosis or cryptogenic fibrosing alveolitis . However, idiopathic pulmonary fibrosis tends to be a very rapidly progressive condition whilst asbestosis tends to involve gradual deterioration so the two conditions can usually be distinguished.

Diagnosis of Asbestosis

The diagnosis of asbestosis, however, may be difficult to make. The diagnosis is made by obtaining a history of asbestos exposure, typical x-ray signs, lung function studies and clinical signs such as inspiratory (respiratory) crackling. Clubbing of the fingers and toes is rare.

The first modern evidence of fibrotic pulmonary disorder in an asbestos worker was discovered in an autopsy performed by Dr Montague-Murray in England in 1899, and reported on in 1907. There is a popular misconception that asbestos-related disease is less of a problem because the exposure to asbestos is less than it was in the 1960s and 1970s.  However, the number of cases of some forms of asbestos-related disease, namely mesothelioma, is increasing.

However, the advent of high resolution CT scanning in the 1990s which shows much more detail of the lung as compared to a simple chest x-ray has given respiratory specialists much more information to make the diagnosis of asbestosis and in far the diagnosis of asbestosis is probably on the increase.

Treatment of Asbestosis

Whilst Asbestosis is irreversible, there are treatments available to sufferers to slow progression and help them to live many years after their diagnosis. The most common treatments for Asbestosis are breathing treatments and medication. Surgery may also be available, although it is rare.

The available treatment and medications are generally palliative, meaning that they will not cure the disease, simply improve and allow the sufferers to lead a quality life. In most cases, doctors will prescribe inhalers and medications such as bronchodilators, humidifiers and oxygen therapy.

If the symptoms of the sufferer are severe, surgery may be required to remove the scar tissue. Anyone who is suffering from Asbestosis should avoid smoking as research found that smoking speeds up and worsens the condition.

How can AMAA help you

For more information on the symptoms, treatments and management of Asbestosis, please contact the Asbestosis & Mesothelioma Association of Australia (AMAA) on 1800 017 758 or via our contact us form today.