The most common symptom of all forms of interstitial lung disease is shortness of breath. Nearly all people with interstitial lung disease will experience breathlessness, particularly with exertion, which may get worse over time.
Other symptoms of interstitial lung disease include dry cough and fevers, which is most common in people with cryptogenic organizing pneumonia (COP). COP is sometimes also referred to as bronchiolitis obliterans with organizing pneumonia (BOOP) and is often confused with a community acquired bacterial pneumonia.
In most forms of interstitial lung disease, the shortness of breath develops slowly, over a period of months. However, in drug-induced interstitial pneumonias or acute interstitial pneumonitis, symptoms come on more rapidly, within hours or days.
Causes and Risk Factors
While the cause of most interstitial lung disease is unknown, some known causes include infections such as bacteria, viruses and fungi. Some interstitial lung diseases also may be caused by regular exposures at work or during hobbies to inhaled irritants, such as asbestos, silica dust, talc, coal or metal dusts from mining work, grain dust from farming and bird proteins, such as from exotic birds, chickens, or pigeons.
There are drugs which can cause interstitial lung disease in rare instances, including nitrofurantoin, amiodarone, bleomycin, and others.
Other factors that may make you more susceptible to interstitial lung disease such as pulmonary fibrosis are age, with adults being much more likely to be affected, exposure to occupational and environmental toxins, smoking, radiation and chemotherapy, and continual inhalation of very high levels of therapeutic oxygen for more than 48 hours.