Asbestosis is a non-malignant inflammatory lung disease that is linked with the inhalation of asbestos fibers. When asbestos fibers are inhaled, they can become lodged in the mouth, throat and lungs, where they remain because of their relative indestructibility. Over time, the lodged asbestos fibers cause scarring of the parenchymal lung tissue, resulting in diminished total lung capacity (TLC).
Parenchymal scarring is not the result of the asbestos fibers themselves; rather, it is caused by the release of certain digestive molecules (macrophages) that are produced by the immune system in an effort to dissolve the trapped fibers. The inability of digestive molecules to dissolve trapped asbestos fibers results in a continuous re-releasing of said macrophages; this leads to increased levels of parenchymal scarring.
Symptoms of Asbestosis
Asbestosis has a number of presenting symptoms that can lead doctors towards definitively diagnosing the non-malignant lung disease. The most common symptom of asbestosis is a feeling of breathlessness that results from a diminished lung capacity. The decreased capacity prevents the lungs from exchanging necessary levels of oxygen and carbon dioxide in the blood, creating inadequate blood-oxygen levels throughout the body.
In addition to the feeling of breathlessness, there are a number of other asbestosis symptoms that can indicate the presence of the non-malignant lung disease:
- General fatigue / malaise
- Chronic cough
- Chronic chest pain
- Congestive heart failure
Diagnosis of Asbestosis
An asbestosis sufferer will typically visit their doctor complaining of some of the aforementioned asbestosis symptoms. A physical examination of the patient is typically followed with a diagnostic chest imaging test (x-ray, MRI, CT scan).
Unlike the more serious asbestos lung diseases, a biopsy is not necessarily required for the purpose of diagnosis. The fibrotic scarring of the lungs that is associated with asbestosis is clearly viewable on a variety of chest imaging scans. A biopsy will only be required if the doctor suspects that the scarring is merely a symptom of a more serious condition.
Treatments for Asbestosis
As is the case with many of the asbestos diseases, there are no curative treatments for asbestosis. Instead, asbestosis treatments focus on palliation, lessening the effects of the debilitating symptoms associated with the chronic inflammatory lung disease.
Oxygen therapy is often administered to asbestosis sufferers experiencing chronic breathlessness. Another common procedure used to remove excess mucous from the lung tissue is referred to as postural drainage (used in conjunction with chest percussion). Medications are often prescribed to help thin lung secretions and clear the peripheral airways.
Asbestos exposure has been linked with the development of a number of diseases of varying severity. Although asbestosis is considered to be a serious asbestos disease, its effects are relatively minor when compared with those of asbestos lung cancer and malignant mesothelioma, two diseases that are both malignant and fatal.
Malignant Mesothelioma Types
Malignant mesothelioma is the most serious of the asbestos diseases because it is highly aggressive and has thus far proven to be incurable. There are three types of malignant mesothelioma that one can suffer from: pleural mesothelioma (occasionally mistaken for asbestosis), peritoneal mesothelioma or pericardial mesothelioma.
Unlike asbestosis, malignant mesothelioma cannot be definitively diagnosed without the aid of a biopsy. A sample of suspect tissue is removed for the purpose of histological examination. A histopathologist can verify a mesothelioma diagnosis, type the disease, recommend treatment and apply to it one of three histological classifications (based on cellular structure): epithelioid mesothelioma, sarcomatoid mesothelioma or biphasic mesothelioma.