Intrinsic Lung Disease

Intrinsic means belonging to or lying within a given part of the anatomy, as defined by Dictionary.com. Therefore, intrinsic lung diseases are diseases that occur within the lungs or are associated with the lungs. With varying categories of intrinsic lung diseases, these diseases take many forms. Proper lung function is impaired in people with lung diseases, including sarcoidosis and asthma.

Facts

• Intrinsic lung diseases, explains eMedicine.com, cause inflammation or scarring of lung tissue (or interstitial lung disease) and fill in air spaces with debris (or pneumonitis). Intrinsic lung diseases include idiopathic fibrotic diseases, connective-tissue diseases, drug-induced lung diseases and primary lung diseases and are also called parenchymal lung disorders. Diffuse interstitial lung disease is a group of lung diseases characterized by scarring of deep lung tissue and is also called diffuse parenchymal lung disease.

Causes

• Exposure to dust, metals, organic solvents and agricultural employment increases your risk for intrinsic lung diseases. Specific factors include exposure to asbestos, coal dust, cotton dust and sand or silica dust. Bird-keeping and bathing in hottubs may also increase your risks. Cigarette smoking may worsen the severity of the disease. Some medications may also cause intrinsic lung disease.

Physiological Effects

• Physiological effects of intrinsic lung disease reduce your exhalation in proportion to lung volume. Scarring and swelling of the air sacs--or alveoli--and their supporting structures--the interstitium---leads to reduced levels of oxygen. As your lungs are restricted by their elasticity, you are not able to inhale as much oxygen as normal. This reduces the amount of incoming oxygen and increases your breathing in an attempt to make up the difference in oxygen and causes hyperventilation at rest and while exercising. Not having sufficient levels of oxygen in your blood causes arterial hypoxemia by impairing the saturation of oxygen to other areas of your body during exercise.

Types

• Types of intrinsic lung disease include sarcoidosis, scleroderma, idiopathic pulmonary fibrosis and non-allergic asthma. Sarcoidosis is a primary lung disease that occurs in 10 to 40 cases per every 100,000 people in North America. Scleroderma is a connective-tissue disease that involves changes in the skin, blood vessels, muscles and internal organs. According to eMedicine.com, the median survival rate for people with idiopathic pulmonary fibrosis is less than three years. Non-allergic asthma occurs when there is an obstruction of the airways to the lungs by constricted muscles, inflammation and swelling, and increased mucus that is not due to allergies; it is reversible with medications or spontaneously.

Considerations

• Some intrinsic lung diseases become apparent in people 20 to 40 years old, including sarcoidosis, collagen-vascular-associated diseases and histiocytosis X. People who are exposed to known causes of intrinsic lung diseases occupationally are routinely screened. Recovery depends on the cause of the disease and how severe the disease was when first diagnosed. Anti-inflammatory medications may be prescribed for treatment. If treatment is not possible, oxygen may be prescribed to relieve the symptoms. Lung transplants are another form of treatment.