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Idiopathic Pulmonary Fibrosis

By

Joyce Lee

, MD, MAS, University of Colorado Denver

Last full review/revision Jun 2021| Content last modified Jun 2021
Click here for the Professional Version

Idiopathic pulmonary fibrosis is the most common form of idiopathic interstitial pneumonia.

  • Idiopathic pulmonary fibrosis affects mostly people over the age of 50, usually former smokers.

  • People may cough, have difficulty breathing, and feel tired.

  • Pulmonary rehabilitation, lung transplantation, and drugs such as pirfenidone and nintedanib, are treatments.

In idiopathic pulmonary fibrosis, the lungs develop progressive scarring for unknown reasons. There seems to be a genetic component because some families have more than one person affected by the disorder. Specific gene mutations have been identified in some people with idiopathic pulmonary fibrosis.

Symptoms of Idiopathic Pulmonary Fibrosis

Symptoms depend on the extent of the lung damage, the rate at which the disease progresses, and whether complications, such as lung infections and right-sided heart failure (cor pulmonale Cor Pulmonale Cor pulmonale is enlargement and thickening of the ventricle on the right side of the heart resulting from an underlying lung disorder that causes pulmonary hypertension (high pressures in the... read more ) develop.

The main symptoms start insidiously as shortness of breath during exertion, cough, and diminished stamina. In most people, symptoms worsen over a period ranging from about 6 months to several years.

As the disease progresses, the level of oxygen in the blood decreases, and the skin may take on a bluish tinge (called cyanosis) and the ends of the fingers may become thick or club-shaped (see figure Recognizing Finger Clubbing ). Strain on the heart may cause the right ventricle to enlarge, eventually resulting in right-sided heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more Heart Failure (HF) . Through a stethoscope, doctors often hear crackling sounds in the lungs.

Diagnosis of Idiopathic Pulmonary Fibrosis

  • Chest computed tomography

  • Sometimes lung biopsy

A chest x-ray may show lung damage, mostly in the lower parts of both lungs. Computed tomography (CT) typically shows the damage and thick scarring in more detail. Pulmonary function tests Pulmonary Function Testing (PFT) Pulmonary function tests measure the lungs' capacity to hold air, to move air in and out, and to absorb oxygen. Pulmonary function tests are better at detecting the general type and severity... read more Pulmonary Function Testing (PFT) show that the amount of air the lungs can hold is below normal. Analysis of a blood sample (see Arterial Blood Gas Analysis Arterial Blood Gas (ABG) Analysis and Pulse Oximetry Both arterial blood gas testing and pulse oximetry measure the amount of oxygen in the blood, which helps determine how well the lungs are functioning. Arterial blood gas tests are invasive... read more ) or use of an oximeter shows a low level of oxygen during minimal exercise (walking at a normal pace) and, as the disease progresses, even when the person is resting.

Blood tests cannot confirm the diagnosis but are done as part of the search for other disorders that may cause a similar pattern of inflammation and scarring. For example, doctors do blood tests to screen for certain autoimmune disorders.

Treatment of Idiopathic Pulmonary Fibrosis

  • Pirfenidone or nintedanib

  • Pulmonary rehabilitation

  • Treatment of symptoms

Most people continue to get worse. On average, people live about 3 to 5 years after diagnosis. Some people survive for more than 5 years after diagnosis. A few die within several months.

Pirfenidone and nintedanib appear to slow the decline in lung function. Other drug treatments are being studied in clinical trials.

Other treatments are aimed at relieving symptoms:

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