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Lung Disease & Respiratory Health Center

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Interstitial Lung Disease

Interstitial lung disease is a general category that includes many different lung conditions. All interstitial lung diseases affect the interstitium, a part of the lungs' anatomic structure.

The interstitium is a lace-like network of tissue that extends throughout both lungs. The interstitium provides support to the lungs' microscopic air sacs (alveoli). Tiny blood vessels travel through the interstitium, allowing gas exchange between blood and the air in the lungs. Normally, the interstitium is so thin it can't be seen on chest X-rays or CT scans.

Recommended Related to Lung Disease/Respiratory Problems

LAM Lung Disease (Lymphangioleiomyomatosis)

LAM lung disease (lymphangioleiomyomatosis) is a rare lung disease that tends to affect women of childbearing age. In LAM lung disease, muscle cells that line the lungs' airways and blood vessels begin to multiply abnormally. These muscle cells spread into areas of the lung where they don't belong. The air sacs in the lung also swell and form small pockets called cysts. As the cysts develop throughout the lungs, LAM causes breathing problems similar to emphysema. The muscle cells can spread...

Read the LAM Lung Disease (Lymphangioleiomyomatosis) article > >

Types of Interstitial Lung Disease

All forms of interstitial lung disease cause thickening of the interstitium. The thickening can be due to inflammation, scarring, or extra fluid (edema). Some forms of interstitial lung disease are short-lived; others are chronic and irreversible.

Some of the types of interstitial lung disease include:

Interstitial pneumonia: Bacteria, viruses, or fungi may infect the interstitium of the lung. A bacterium called Mycoplasma pneumonia is the most common cause.

Idiopathic pulmonary fibrosis : A chronic, progressive form of fibrosis (scarring) of the interstitium. Its cause is unknown.

Nonspecific interstitial pneumonitis: Interstitial lung disease that's often present with autoimmune conditions (such as rheumatoid arthritis or scleroderma).

Hypersensitivity pneumonitis: Interstitial lung disease caused by ongoing inhalation of dust, mold, or other irritants.

Cryptogenic organizing pneumonia (COP): A pneumonia-like interstitial lung disease but without an infection present. COP is also called bronchiolitis obliterans with organizing pneumonia (BOOP).

Acute interstitial pneumonitis: A sudden, severe interstitial lung disease, often requiring life support.

Desquamative interstitial pneumonitis: An interstitial lung disease that's partially caused by smoking.

Sarcoidosis: A condition causing interstitial lung disease along with swollen lymph nodes, and sometimes heart, skin, nerve, or eye involvement.

Asbestosis: Interstitial lung disease caused by asbestos exposure.

Causes of Interstitial Lung Disease

Bacteria, viruses, and fungi are known to cause interstitial pneumonias. Regular exposures to inhaled irritants at work or during hobbies can also cause some interstitial lung disease. These irritants include:

  • Asbestos
  • Silica dust
  • Talc
  • Coal dust, or various other metal dusts from working in mining
  • Grain dust from farming
  • Bird proteins (such as from exotic birds, chickens, or pigeons)
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