Asbestosis (definition of)

Like mesothelioma, asbestosis is caused by exposure to asbestos fibers (other risk factors include exposure to radiation, zeolite, and tobacco). This is the disease that was suffered by the majority of the miners and their families who worked for the W.R. Grace Corporation in Libby, Montana. Specifically, it is caused by inhaling the fibers of "white," or chrysotile asbestos, which historically accounts for about 95% of all commercial asbestos.

Unlike mesothelioma, asbestosis is non-malignant - and once the patient is removed from the asbestos environment, the disease is stopped from progressing further. However, by the time the damage is done, and is irreversible. The latency period for mesothelioma can be as short as 10 years or as long as 50 years between exposure and diagnosis and varies from patient to patient.

Symptoms

The disease develops gradually over a period of several years. The primary symptom is shortness of breath; chronic cough is usually not a direct result of asbestosis. Eventually, the patient's oxygen capacity is severely compromised; it is essentially slow suffocation, which can ultimately result in heart failure.

Half of asbestosis cases result in non-malignant pleural thickening and fibrosis. Breathing may sound like air going into a dry paper bag, and there may be a clubbing of the fingers due to hypoxia (oxygen deprivation).

Pathology

Unlike hard, needle-like amphibole asbestos fibers, chrysotile asbestos is relatively soft and curly. These fibers do not drill through lung tissue in the way amphibole asbestos fibers do. However, once inhaled they begin to scratch and irritate the inner lung surfaces, causing the build-up of scar tissue that over time reduces lung capacity.

Treatment

Like mesothelioma, asbestosis is incurable. Palliative treatments include oxygen therapy and postural draining of lung secretions; nebulized medications may also be prescribed to help in diluting such secretions.