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
The Mantoux skin test -- -- also commonly known as PPD and performed in a doctor's office or health department -- is a reliable detector of TB in most people. A small amount of liquid material is injected just under the top layer of skin on your arm. After two to three days, a doctor or nurse will evaluate your arm to see if the test is positive. If it is, you will have a hard, red welt at the injection site. A positive result means you have been infected with TB, even if the infection is not active...
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.
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:
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)