Asbestosis

Definition

Asbestosis is a respiratory disease brought on by inhaling asbestos fibers.

Alternative Names

Pulmonary fibrosis - from asbestos exposure; Interstitial pneumonitis - from asbestos exposure

Causes, incidence, and risk factors

Inhaling asbestos fibers can cause scar tissue (fibrosis) to form inside the lung. Scarred lung tissue does not expand and contract normally, and cannot perform gas exchange.

The severity of the disease depends on how long the person was exposed to asbestos and the amount inhaled. Often, symptoms and lung fibrosis do not occur and are not noticed for a period of 20 years or more after the asbestos exposure.

Asbestos fibers were commonly used in construction before 1975. Asbestos exposure occured in asbestos mining and milling industries, construction, fireproofing, and other industries. In families of asbestos workers, exposure can also occur from particles brought home on the worker's clothing.

Asbestos-related disease includes pleural plaques (calcification), malignant mesothelioma, and pleural effusion. Mesotheliomas may develop 20 - 40 years after exposure. Workers today are less likely to develop asbestos-related disease because of government regulations.

Cigarette smoking increases the risk of developing the disease.

Symptoms

• Chest pain
• Cough
• Shortness of breath on exertion (slowly gets worse over time)
• Tightness in the chest

Possible additional symptoms include the following:

• Nail abnormalities
• Clubbing of fingers

Signs and tests

When listening to the chest with a stethoscope (auscultation), the doctor may detect a crackling sound.

• Chest x-ray
• CT scan of the lungs
• Gallium lung scan
• Pulmonary function tests

Treatment

There is no cure available. Stopping further exposure to asbestos is essential. To ease symptoms, postural drainage, chest percussion, and vibration can help remove secretions from the lungs.

The doctor may prescribe aerosol medications to thin secretions. People with this condition may need to receive oxygen by mask or by a plastic piece that fits into the nostrils. Certain patients may require lung transplantation.

Support Groups

You can ease the stress of this illness by joining a support group whose members share common experiences and problems. See lung disease - support group.

Expectations (prognosis)

The outcome depends on the duration and extent of the asbestos exposure. Patients who develop malignant mesothelioma have a poor probable outcome, with 75% of those affected dying within 1 year.

Complications

• Malignant mesothelioma
• Pleural effusion

Calling your health care provider

Call for an appointment with your health care provider if you suspect that you've been exposed to asbestos or if you have unexplained symptoms.

Prevention

In people who are exposed to asbestos, early screening by chest x-ray may help prevent asbestosis.

References

Cowie RL, Murray J, Becklake MR. Pneumoconioses. In: Mason RJ, Murray JF, Broaddus VC, Nadel JA, eds. Textbook of Respiratory Medicine. 4th ed. Philadelphia, Pa : Saunders Elsevier; 2005: chap 61.

Glazer CS, Newman LS. Occupational interstitial lung disease. Chest. September 2004;25:467-478.