Idiopathic pulmonary fibrosis is a disease of the lower respiratory tract that damages the air sacs (alveoli) and leads to reduced transfer of oxygen to the blood. It causes widespread scarring of the lung.

The condition is believed to result from an inflammatory response to an unknown agent -- "idiopathic" means no cause can be found. The disease occurs most often in people between 50 and 70 years old. Nearly 75% of patients with idiopathic pulmonary fibrosis have smoked cigarettes.

• Shortness of breath on exertion that lasts for months or years and eventually is present at rest
• Decreased tolerance for activity
• Cough (usually dry)
• Chest pain (occasionally)

In addition to a physical examination, your health care provider will take a careful history in order to exlude other similar diseases.

Patients with idiopathic pulmonary fibrosis have dry, Velcro-like breath sounds called crackles. Patients with advanced disease may have cyanosis (blueness around the mouth or in the fingernails due to low oxygen).

Examination of the fingers and toes may reveal clubbing (abnormal enlargement of the tips).

Tests that help diagnose idiopathic pulmonary fibrosis include the following:

• Chest X-ray
• High-resolution CT scan of the chest
• Pulmonary function tests
• Bronchoscopy with transbronchial lung biopsy
• Surgical lung biopsy
• Measurement of blood oxygen level at rest or during exertion
• Tests for connective tissue diseases such as rheumatoid arthritis, lupus, or scleroderma

No known cure exists for idiopathic pulmonary fibrosis. Medications such as corticosteroids and cytotoxic drugs may be given to suppress inflammation, but these treatments are usually unsuccessful. Oxygen is given to patients who have low blood oxygen levels.

Recently, interferon-gamma-1B has shown some promise in treating this disease, but more research is necessary to demonstrate that this drug is beneficial.

Lung transplantation may be indicated for some patients with advanced pulmonary fibrosis.

The stress of illness can often be helped by joining a support group where members share common experiences and problems. See lung disease - support group.

Some patients may improve on treatment with corticosteroids or cytotoxic drugs, but most patients suffer from progressive disease despite treatment. Pulmonary hypertension (high blood pressures in the vessels of the lungs) and respiratory failure is the eventual outcome. Average survival time is 5-6 years, but this varies greatly between patients.

• respiratory failure
• chronic hypoxemia (low blood oxygen level)
• pulmonary hypertension
• cor pulmonale (failure of the right side of the heart)
• polycythemia (abnormally high levels of red blood cells)

Call for an appointment with the health care provider if persistent cough or shortness of breath develops.

Avoiding smoking may help prevent this condition but its cause, and therefore more specific prevention, is not known.