Pulmonary fibrosis (also known as interstitial lung disease or ILD) is a chronic (long-term) disease where the lungs (pulmonary) become scarred (fibrosis). The scarring causes the part of the lung where oxygen is moved to the blood (interstitial) to become thick and stiff. If the reason or cause of the disease is unknown, it is called idiopathic. Pulmonary fibrosis is a restrictive disease because it is hard to fully expand the lungs when taking a breath in (i.e., the lungs are restricted when taking a breath in).
How Common is Pulmonary Fibrosis?
Pulmonary fibrosis and idiopathic pulmonary fibrosis (IPF) are a subgroup of interstitial lung diseases called interstitial pneumonia. IPF is the most common of the Interstitial Lung Diseases (ILDs), affecting 14,000 to 15,000 Canadians. It is more common in males over the age of 50.
We often don’t think about our breathing until something takes our breath away. When the lungs become scarred, for example in pulmonary fibrosis, it is hard to get oxygen to the organs and the rest of the body. The lack of oxygen can cause different symptoms. Knowing what to look for is important so you and your healthcare provider can come up with a plan to diagnose the problem.
People with pulmonary fibrosis may have some or all the following symptoms:
- shortness of breath, especially during or after physical activity
- a dry cough
- inspiratory crackles – this is a ‘velcro-like’ crackling sound in the lungs that can be heard when listening with a stethoscope
- toe/finger clubbing – about one half of people with idiopathic pulmonary fibrosis or IPF have rounding and widening of the fingers and toes
- unintended weight loss and feeling unwell (fatigue and weakness)
Speak with your healthcare provider if you have these symptoms.
There are several known causes of pulmonary fibrosis, as well as unknown causes. Known causes of lung scarring (fibrosis) include:
- Medical tests and treatments: Certain medications such as for inflammation (anti-inflammatory), infections (antibiotic), and cancer (chemotherapy) can cause scarring in the lungs. Medical tests like radiation therapy are also linked to pulmonary fibrosis.
- Occupational or Environmental Exposures: Inhaling toxic compounds such as coal (coal workers’ pneumoconiosis), silica (silicosis), and asbestos (asbestosis) can cause scarring in the lungs that may lead to pulmonary fibrosis. Also, certain inhaled drugs or chemicals such as cocaine, zinc chloride, and ammonia are known to cause scarring in the lungs.
- Autoimmune Disease: There is some proof that pulmonary fibrosis can be caused by autoimmune diseases like rheumatoid arthritis, scleroderma, and systemic lupus erythematosus (SLE). In autoimmune disease the body’s natural defense system mistakenly attacks normal cells and causes the disease.
When no cause for pulmonary fibrosis can be identified the disease is termed idiopathic pulmonary fibrosis or IPF. Idiopathic simply means ‘of unknown cause’.
Risk Factors for IPF (idiopathic pulmonary fibrosis)
Although IPF is a disease of unknown cause, there are several potential risk factors for the development of IPF that are known. They include:
- Smoking is one of the most recognized risk factors.
- Environmental Exposures: Certain jobs and occupations such as farming, raising birds, hair dressing, and stone cutting/polishing may be connected. Contact with livestock and different kinds of dust (metal, wood, vegetable and animal) are also risk factors.
- Gastroesophageal Reflux Disease (GERD): GERD is a chronic digestive disease. GERD occurs when stomach acid or content flows back into your food pipe (esophagus). This backwash (reflux) irritates the lining of your esophagus and is what causes GERD. GERD may also be related to IPF, however more research is still needed in this area.
- Genetics: Genetics can play a role in IPF. A very small percentage of people with IPF have reported two or more family members with the disease.
- Gender: IPF is more common in men than women.
- Age: IPF is more common in people 50 years and older. The risk of getting IPF for both women and men increases with age.
There is no single test to diagnose pulmonary fibrosis, so it may take some time to determine if you have the disease. You will likely need to undergo many different tests and often healthcare providers will first rule out other possible diseases. They often start with tests that are the least invasive and only order more if needed. These tests will help toward a better understanding of your condition. Below are some of the steps and tests that will help your healthcare provider make the right diagnosis for you.
- Medical History: As a first step, your healthcare provider will ask about you and your family’s health. They will want to know any symptoms you may be having (e.g. coughing or shortness of breath during physical activity) and if you have any other medical conditions.
- Physical Examination: Your healthcare provider will check for any visible signs and symptoms that could indicate pulmonary fibrosis.
- Oxygen Testing: This test measures the oxygen in your blood (oxygen saturation). Your healthcare provider will clip a ‘probe’ to your finger to measure and monitor how much oxygen is in your blood. This alone does not diagnose IPF but can be one of the tests that assists with a diagnosis.
- Arterial Blood Gases (ABGs): ABGs measure the amount of oxygen that is carried in your blood. A blood sample is usually taken from an artery in your wrist.
- Pulmonary Function Tests (PFTs): PFTs or ‘breathing tests’ are a series of tests used to find out how well you move air in and out of your lungs and how well oxygen enters your bloodstream from your lungs.
- Six Minute Walk Test (6MWT): Shortness of breath when exercising or doing physical activity can be a common first symptom for people with pulmonary fibrosis. This test measures how far you can walk in six minutes, how difficult it was for you to walk in the six minutes, and if your oxygen levels dropped while walking.
- Blood Test: Although a blood test cannot confirm pulmonary fibrosis, it can be used to help rule out other lung-related conditions.
- Chest Radiography (x-ray): A chest x-ray uses electromagnetic waves to create pictures of the structures in and around your chest. It will often provide useful information such as the size of your lungs and can also help rule out other lung diseases.
- Bronchoscopy: A bronchoscopy allows the doctor to look through your nose or mouth into the trachea (windpipe) and down to the bronchi (large airways) in your lungs.
- High Resolution Computed Tomography (HRCT): Also known as a CAT or CT scan, these scanners are able to take more detailed x-rays of the chest.
- Lung Biopsy: A lung biopsy involves small incisions into the side of the chest to remove a small part of the lung tissue and examine it under a microscope.
Currently there are two approved drugs in Canada for the treatment of idiopathic pulmonary fibrosis (IPF), which is the most common form of pulmonary fibrosis:
- Nintedanib (Ofev®)
- Pirfenidone (Esbriet®, Sandoz®)
These medications are called anti-fibrotic agents, meaning they are used to slow down the rate of fibrosis or scarring in the lungs.
For information about medication coverage in Alberta:
- Supplemental Oxygen Therapy can be prescribed by a healthcare provider. It is not a cure for pulmonary fibrosis, and it will not take away your shortness of breath. However, it will treat low blood oxygen levels that can occur when pulmonary fibrosis worsens. Oxygen in the blood is needed for all organs, including your brain to repair and function.
- Steroids: There are certain types of pulmonary fibrosis (excluding IPF) that can be treated using steroids. Steroids are a type of medication that reduce inflammation (swelling).
- Medications for Acid Reflux: Gastroesophageal reflux disease (GERD) is a digestive condition that commonly occurs in people with IPF. There are different types of anti-acid medications that might be prescribed to help block the formation (or lessen) the amount of acid in the stomach.
- Medications for cough: A dry cough is a common symptom of pulmonary fibrosis. Because what works for one person might not work for another, treating a dry cough can be trial and error. Medications for cough might include over the counter medication or prescription cough medication.