Overview of Idiopathic Interstitial Pneumonias

ByJoyce Lee, MD, MAS, University of Colorado School of Medicine
Reviewed/Revised Jul 2023
VIEW PROFESSIONAL VERSION

Idiopathic interstitial pneumonias are interstitial lung diseases that have no known cause that have some similarities in symptoms and how they affect the lungs.

  • Some types of these diseases are much more serious than others.

  • Diagnosis requires chest x-rays, computed tomography, and occasionally analysis of a sample of lung tissue (biopsy).

  • Treatment depends on the disease type.

(See also Overview of Interstitial Lung Diseases.)

The word idiopathic means of unknown cause, so when the cause of interstitial lung disease is not identified, idiopathic interstitial pneumonia is diagnosed. Pneumonias are often thought of as infections, but these diseases do not appear to result from infection.

There are eight types of idiopathic interstitial pneumonias. In decreasing order of frequency, they are

All types cause cough and shortness of breath and affect the lungs similarly. The ends of the fingers may become thick or club-shaped (see figure Recognizing Finger Clubbing). Through a stethoscope, doctors often hear crackling sounds. Although symptoms may be similar, disorders differ in how quickly symptoms develop, how they are treated, and how serious they are.

Table
Table

Diagnosis of Idiopathic Interstitial Pneumonias

  • Chest computed tomography

Computed tomography (CT) of the chest is the main imaging tool used in the evaluation of idiopathic interstitial pneumonias. CT may allow doctors to make a diagnosis. If not, doctors remove a small sample of lung tissue for examination under a microscope (lung biopsy). Usually, biopsy is done surgically with use of a thoracoscope.

Blood tests are usually done. They usually cannot confirm the diagnosis but are done as part of the search for other disorders. Doctors may also do electrocardiography (ECG) or echocardiography to determine whether the heart has been affected by the lung disease.

Treatment of Idiopathic Interstitial Pneumonias

  • Smoking cessation

  • Often drugs, corticosteroids or novel antifibrotic drugs, depending on the disease

  • Sometimes lung transplantation

Smoking cessation is always recommended because smoking is likely to make the disorder progress more rapidly.

Other treatments depend on the type of idiopathic interstitial pneumonia but may include corticosteroids or other drugs, such as novel antifibrotic drugs.

In some people, lung transplantation is done.

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