Silicosis is a respiratory disease caused by inhalation of silica dust, which leads to inflammation and scarring of the lung tissue.
Three types of silicosis are seen:
Progressive massive fibrosis may occur in simple or accelerated silicosis, but is more common in the accelerated form. Progressive massive fibrosis results from severe scarring and leads to obliteration of normal lung structures.
Silica is a common, naturally-occurring crystal. It is found in most rock beds and forms dust during mining, quarrying, tunneling, and work with many metal ores. Silica is a main component of sand, so glass workers and sand-blasters also receive heavy exposure to silica.
Risk factors include any work that includes exposure to silica dust. Mining, stone cutting, quarrying, road and building construction, work with abrasives manufacturing, sand blasting and many other occupations and hobbies involve exposure to silica.
Intense exposure to silica may result in disease in a year or less, but it usually takes at least 10 or 15 years of exposure before symptoms develop. Silicosis has become less common since the Occupational Safety and Health Administration (OSHA) instituted regulations requiring the use of protective equipment which limit the amount of silica dust inhaled.
Additional symptoms that may be associated with this disease, especially in acute silicosis:
Your health care provider will take a careful medical history that includes many questions about your occupations (past and present), your hobbies, and other activities that may have exposed you to excessive silica. A physical exam will also be performed. Diagnostic tests to confirm the diagnosis and exclude other diseases that may appear similar include:
There is no specific treatment for silicosis. Removal of the source of silica exposure is important to prevent further worsening of the disease. Supportive treatment includes cough suppression medications, bronchodilators, and oxygen if needed. Antibiotics are prescribed for respiratory infections as needed.
Other considerations for treatment include limiting continued exposure to irritants, smoking cessation, and routine tuberculosis skin testing.
People with silicosis are at high risk for developing tuberculosis (TB). Silica is believed to interfere with the body's immune response to the bacteria that causes TB. Yearly skin testing to check for exposure to TB is recommended. Treatment with anti-TB drugs is recommended for people with a positive skin test. Any change in the appearance of the chest x-ray may indicate TB.
Support groups with others who suffer from silicosis or related diseases may help you understand your disease and adapt to its treatments and other changes in your life that result from it.
The outcome varies and depends upon the extent of damage to the lungs.
Call your health care provider if you have an occupational exposure to silica and symptoms develop.
If you work in a high-risk occupation or have a high-risk hobby, wear dust masks and do not smoke. Other protection prescribed by OSHA, such as a respirator, may be indicated.
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