When all known causes of interstitial lung disease have been ruled out, the condition is called "idiopathic" (of unknown origin) pulmonary fibrosis (IPF).
There are several theories as to what may cause IPF; including viral illness and allergic or environmental exposure (including tobacco smoke). These theories are still being researched. Bacteria and other microorganisms are not thought to be the cause of IPF.
There is also a familial form of the disease, known as familial idiopathic pulmonary fibrosis. Additional research is being done to determine whether there is a genetic tendency to develop the disease, as well as to determine other causes of IPF.
What are the symptoms of IPF?
Shortness of breath is the main symptom of idiopathic pulmonary fibrosis. Since this is a symptom of many types of lung disease, making the correct diagnosis may be difficult. The shortness of breath may first appear during exercise. The condition then may progress to the point where any exertion is impossible. If the disease progresses, the person with IPF eventually may be short of breath even at rest.
Other symptoms may include a dry cough (without sputum). When the disease is severe and prolonged, heart failure with swelling of the legs may occur.
How is IPF diagnosed?
A very careful patient history is an important tool for diagnosis. The history will include environmental and occupational factors, hobbies, legal and illegal drug use, arthritis, and risk factors for diseases that affect the immune system. A physical examination, chest X-ray, pulmonary function tests, and blood tests are important. These tests will help your doctor rule out other lung diseases and determine the extent of disease.
Bronchoalveolar lavage (BAL) - a test which permits removal and examination of cells from the lower respiratory tract -- may be used to diagnose IPF: this test helps a doctor identify inflammation in lung tissue, and also helps exclude infections and malignancies (cancer) as a cause of a patient's symptoms. The test is done during bronchoscopy, a special examination of the lung.
Lung biopsy - Either done during bronchoscopy or as a surgical procedure that removes a sample of lung tissue for your doctor to study -- this proceedure is usually required for for diagnosis of IPF.
Diagnostic Tests That May Be Used to Identify Pulmonary Fibrosis or Interstitial Lung Disease
What is the treatment for IPF?
Corticosteroids may be administered to treat the inflammation present in some people with IPF. The success of this treatment for many forms of pulmonary fibrosis is variable and is still being researched. Other drugs are occasionally added when it is clear that the steroids are not effective in reversing the disease.
Some doctors may use corticosteroids in combination with other drugs when the diagnosis is first established. Which drug treatment plan is effective, and how long to use the drugs is the focus of current research.
Oxygen therapy may be prescribed for some people with IPF. The need for oxygen will be determined by your doctor and may depend on the severity of disease, as well as your activity level. Talk with you doctor if you think you may need oxygen or if you have concerns about oxygen.
Influenza vaccine and pneumococcal pneumonia vaccine are both recommended for people with IPF or any lung disease. These two shots may help prevent infection and keep you healthy.
Lung transplantation may offer hope for selected people with severe IPF and other lung diseases. Speak with your doctor about eligibility criteria for lung transplant recipients.