What is Pleural Thickening?

Pleural thickening is the thickening, calcification or scarring of the pleura (linings of the lung), mainly affecting the inner surface.

Pleural thickening can develop on one lung or on both lungs (termed diffuse pleural thickening when spread over both lungs) and causes the tissue to harden, which in turn prevents the lungs from working correctly. This makes the sufferer feel breathless.

Symptoms of pleural thickening

Pleural thickening can often only be seen through a CT scan. Common symptoms of pleural thickening include:

  • Breathlessness – this is evident in pulmonary function tests which show a reduced lung capacity
  • Chest pain
  • Feeling of tightness across the chest

Once diffuse asbestos related pleural thickening has formed it may remain static, but could also progress to cause increasing respiratory disability over approximately 8 to 10 years. The symptoms of pleural thickening can also vary from case to case and other factors like the person’s genetic makeup and level of exposure to asbestos can have an impact.

Causes of pleural thickening

Pleural thickening is caused by long term exposure to asbestos and significant inhalation of asbestos fibres and particles. These fibres will settle on the thin area surrounding the lungs, known as the pleura, causing it to thicken, scar or calcify. This scarring is sadly incurable and irreversible and is the cause of impaired lung function in the sufferer.

Diagnosing pleural thickening

Pleural thickening commonly occurs between 15 and 30 years after a person has been exposed to asbestos, this period can be shorter.

While there are a number of tests that medical professionals can use to identify pleural thickening, the most common is through a chest X-ray or CT scan. Pleural thickening will often appear as an irregular shadow that will cover at least 25% of the chest wall.
In more severe cases it may be necessary for a doctor to perform a positron emission tomography (PET) scan. This will allow them to distinguish between pleural thickening and pleural mesothelioma. These two illnesses can affect an individual simultaneously, but a diagnosis of pleural thickening can result in mesothelioma being detected early.

Treatment of pleural thickening

Because the scarring of the lung tissue is irreversible, pleural thickening is unfortunately a disease that has no cure. Pleural thickening is also technically a malignant disease but its presence can develop to cause malignant mesothelioma, which can cause death.

One of the most common treatments for the disease, which is purely palliative, is thoracentesis. This is a surgery that will remove excess fluid that builds up between the lungs and the pleura, restricting how freely they can expand and contract. The fluid that builds up is called pleural effusion and is one of the main symptoms of pleural thickening, it is one of the main causes of pain in sufferers.