Pulmonary fibrosis
Overview
Pulmonary fibrosis is a lung disease that occurs when lung tissue becomes damaged and scarred. This thickened, stiff tissue makes it more difficult for your lungs to work properly. As pulmonary fibrosis worsens, you become progressively more short of breath.
The scarring associated with pulmonary fibrosis can be caused by a multitude of factors. But in most cases, doctors can't pinpoint what's causing the problem. When a cause can't be found, the condition is termed idiopathic pulmonary fibrosis.
The lung damage caused by pulmonary fibrosis can't be repaired, but medications and therapies can sometimes help ease symptoms and improve quality of life. For some people, a lung transplant might be appropriate.
Symptoms
Signs and symptoms of pulmonary fibrosis may include:
- Shortness of breath (dyspnea)
- A dry cough
- Fatigue
- Unexplained weight loss
- Aching muscles and joints
- Widening and rounding of the tips of the fingers or toes (clubbing)
The course of pulmonary fibrosis — and the severity of symptoms — can vary considerably from person to person. Some people become ill very quickly with severe disease. Others have moderate symptoms that worsen more slowly, over months or years.
Some people may experience a rapid worsening of their symptoms (acute exacerbation), such as severe shortness of breath, that may last for several days to weeks. People who have acute exacerbations may be placed on a mechanical ventilator. Doctors may also prescribe antibiotics, corticosteroid medications or other medications to treat an acute exacerbation.
Causes
Pulmonary fibrosis scars and thickens the tissue around and between the air sacs (alveoli) in your lungs. This makes it more difficult for oxygen to pass into your bloodstream. The damage can be caused by many different factors — including long-term exposure to certain toxins, certain medical conditions, radiation therapy and some medications.
Occupational and environmental factors
Long-term exposure to a number of toxins and pollutants can damage your lungs. These include:
- Silica dust
- Asbestos fibers
- Hard metal dusts
- Coal dust
- Grain dust
- Bird and animal droppings
Radiation treatments
Some people who receive radiation therapy for lung or breast cancer show signs of lung damage months or sometimes years after the initial treatment. The severity of the damage may depend on:
- How much of the lung was exposed to radiation
- The total amount of radiation administered
- Whether chemotherapy also was used
- The presence of underlying lung disease
Medications
Many drugs can damage your lungs, especially medications such as:
- Chemotherapy drugs. Drugs designed to kill cancer cells, such as methotrexate (Trexall, Otrexup, others) and cyclophosphamide, can also damage lung tissue.
- Heart medications. Some drugs used to treat irregular heartbeats, such as amiodarone (Cordarone, Nexterone, Pacerone), may harm lung tissue.
- Some antibiotics. Antibiotics such as nitrofurantoin (Macrobid, Macrodantin, others) or ethambutol can cause lung damage.
- Anti-inflammatory drugs. Certain anti-inflammatory drugs such as rituximab (Rituxan) or sulfasalazine (Azulfidine) can cause lung damage.
Medical conditions
Lung damage can also result from a number of conditions, including:
- Dermatomyositis
- Polymyositis
- Mixed connective tissue disease
- Systemic lupus erythematosus
- Rheumatoid arthritis
- Sarcoidosis
- Scleroderma
- Pneumonia
Many substances and conditions can lead to pulmonary fibrosis. Even so, in most cases, the cause is never found. Pulmonary fibrosis with no known cause is called idiopathic pulmonary fibrosis.
Researchers have several theories about what might trigger idiopathic pulmonary fibrosis, including viruses and exposure to tobacco smoke. Also, some forms of idiopathic pulmonary fibrosis run in families, and heredity may play a role in idiopathic pulmonary fibrosis.
Many people with idiopathic pulmonary fibrosis may also have gastroesophageal reflux disease (GERD) — a condition that occurs when acid from your stomach flows back into your esophagus. Ongoing research is evaluating if GERD may be a risk factor for idiopathic pulmonary fibrosis, or if GERD may lead to a more rapid progression of the condition. However, more research is needed to determine the association between idiopathic pulmonary fibrosis and GERD.
Risk factors
Factors that make you more susceptible to pulmonary fibrosis include:
- Age. Although pulmonary fibrosis has been diagnosed in children and infants, the disorder is much more likely to affect middle-aged and older adults.
- Sex. Idiopathic pulmonary fibrosis is more likely to affect men than women.
- Smoking. Far more smokers and former smokers develop pulmonary fibrosis than do people who have never smoked. Pulmonary fibrosis can occur in patients with emphysema.
- Certain occupations. You have an increased risk of developing pulmonary fibrosis if you work in mining, farming or construction or if you're exposed to pollutants known to damage your lungs.
- Cancer treatments. Having radiation treatments to your chest or using certain chemotherapy drugs can increase your risk of pulmonary fibrosis.
- Genetic factors. Some types of pulmonary fibrosis run in families, and genetic factors may be a component.
Complications
Complications of pulmonary fibrosis may include:
High blood pressure in your lungs (pulmonary hypertension). Unlike systemic high blood pressure, this condition affects only the arteries in your lungs. It begins when the smallest arteries and capillaries are compressed by scar tissue, causing increased resistance to blood flow in your lungs.
This in turn raises pressure within the pulmonary arteries and the lower right heart chamber (right ventricle). Some forms of pulmonary hypertension are serious illnesses that become progressively worse and are sometimes fatal.
- Right-sided heart failure (cor pulmonale). This serious condition occurs when your heart's lower right chamber (ventricle) has to pump harder than usual to move blood through partially blocked pulmonary arteries.
- Respiratory failure. This is often the last stage of chronic lung disease. It occurs when blood oxygen levels fall dangerously low.
- Lung cancer. Long-standing pulmonary fibrosis also increases your risk of developing lung cancer.
- Lung complications. As pulmonary fibrosis progresses, it may lead to complications such as blood clots in the lungs, a collapsed lung or lung infections.
Diagnosis
To diagnose your condition, your doctor may review your medical and family history, discuss your signs and symptoms, review any exposure you've had to dusts, gases and chemicals, and conduct a physical exam. During the physical exam, your doctor will use a stethoscope to listen carefully to your lungs while you breathe. He or she may also suggest one or more of the following tests.
Imaging tests
- Chest X-ray. A chest X-ray shows images of your chest. This may show the scar tissue typical of pulmonary fibrosis, and it may be useful for monitoring the course of the illness and treatment. However, sometimes the chest X-ray may be normal, and further tests may be required to explain your shortness of breath.
- Computerized tomography (CT) scan. CT scanners use a computer to combine X-ray images taken from many different angles to produce cross-sectional images of internal structures in the body. A high-resolution CT scan can be particularly helpful in determining the extent of lung damage caused by pulmonary fibrosis. Also, some kinds of fibrosis have characteristic patterns.
- Echocardiogram. An echocardiogram uses sound waves to visualize the heart. It can produce still images of your heart's structures, as well as videos that show how your heart is functioning. This test can evaluate the amount of pressure occurring in the right side of your heart.
Lung function tests
- Pulmonary function testing. Several types of pulmonary function tests may be conducted. In a test called spirometry, you exhale quickly and forcefully through a tube connected to a machine. The machine measures how much air your lungs can hold and how quickly you can move air in and out of your lungs. Other tests may be conducted to measure your lung volumes and diffusing capacity.
- Pulse oximetry. This simple test uses a small device placed on one of your fingers to measure the oxygen saturation in your blood. Oximetry can serve as a way to monitor the course of the disease.
- Exercise stress test. An exercise test on a treadmill or stationary bike may be used to monitor your lung function when you're active.
- Arterial blood gas test. In this test, your doctor tests a sample of your blood, usually taken from an artery in your wrist. The oxygen and carbon dioxide levels in the sample are then measured.
Tissue sample (biopsy)
If other tests haven't diagnosed the condition, doctors may need to remove a small amount of lung tissue (biopsy). The biopsy is then examined in a laboratory to diagnose pulmonary fibrosis or rule out other conditions. The tissue sample may be obtained in one of these ways:
Bronchoscopy. In this procedure, your doctor removes very small tissue samples — generally no larger than the head of a pin — using a small, flexible tube (bronchoscope) that's passed through your mouth or nose into your lungs. The tissue samples are sometimes too small for an accurate diagnosis. The biopsy may also be used to rule out other conditions.
The risks of bronchoscopy are generally minor and might include a temporary sore throat or discomfort in your nose from the passage of the bronchoscope. However, serious complications can include bleeding or a deflated lung.
During bronchoscopy, your doctor may conduct an additional procedure called bronchoalveolar lavage. In this procedure, your doctor injects salt water through a bronchoscope into a section of your lung, and then immediately suctions it out. The solution that's withdrawn contains cells from your air sacs.
Although bronchoalveolar lavage samples a larger area of the lung than other procedures do, it may not provide enough information to diagnose pulmonary fibrosis. It might also be used to rule out other conditions.
Surgical biopsy. Although a surgical biopsy is more invasive and has potential complications, it may be the only way to obtain a large enough tissue sample to make an accurate diagnosis. This procedure may be done as a minimally invasive surgery, called video-assisted thoracoscopic surgery (VATS), or as an open surgery (thoracotomy).
During VATS, your surgeon inserts surgical instruments and a small camera through two or three small incisions between your ribs. The camera allows your surgeon to view your lungs on a video monitor while removing tissue samples from your lungs. This procedure is performed after you've been given a general anesthetic, so you'll be asleep during the procedure.
During open surgery (thoracotomy), a surgeon removes a lung sample through an incision in the chest between your ribs. The procedure takes place after you've been given a general anesthetic.
Blood tests
Doctors may also order blood tests to evaluate your liver and kidney function, and to test for and rule out other conditions.
Treatment
The lung scarring that occurs in pulmonary fibrosis can't be reversed, and no current treatment has proved effective in stopping progression of the disease. Some treatments may improve symptoms temporarily or slow the disease's progression. Others may help improve quality of life. Doctors will evaluate the severity of your condition to determine the most appropriate treatment for your condition.
Medications
Your doctor may recommend newer medications, including pirfenidone (Esbriet) and nintedanib (Ofev). These medications may help slow the progression of idiopathic pulmonary fibrosis. Both medications have been approved by the Food and Drug Administration (FDA). Additional medications and new formulations of these medications are being developed but have not yet been FDA approved.
Nintedanib can cause side effects such as diarrhea and nausea. Side effects of pirfenidone include rash, nausea and diarrhea.
Researchers continue to study medications to treat pulmonary fibrosis.
Doctors may recommend anti-acid medications to treat gastroesophageal reflux disease (GERD), a digestive condition that commonly occurs in people with idiopathic pulmonary fibrosis.
Oxygen therapy
Using oxygen can't stop lung damage, but it can:
- Make breathing and exercise easier
- Prevent or lessen complications from low blood oxygen levels
- Reduce blood pressure in the right side of your heart
- Improve your sleep and sense of well-being
You may receive oxygen when you sleep or exercise, although some people may use it all the time. Some people carry a canister of oxygen, making them more mobile.
Pulmonary rehabilitation
Pulmonary rehabilitation can help you manage your symptoms and improve your daily functioning. Pulmonary rehabilitation programs focus on:
- Physical exercise to improve your endurance
- Breathing techniques that may improve lung efficiency
- Nutritional counseling
- Counseling and support
- Education about your condition
Lung transplant
Lung transplantation may be an option for people with pulmonary fibrosis. Having a lung transplant can improve your quality of life and allow you to live a longer life. However, a lung transplant can involve complications such as rejection and infection. Your doctor may discuss with you if a lung transplant may be appropriate for your condition.
Lifestyle and home remedies
Being actively involved in your own treatment and staying as healthy as possible are essential to living with pulmonary fibrosis. For that reason, it's important to:
Stop smoking. If you have lung disease, it's very important to stop smoking. Talk to your doctor about options for quitting, including smoking cessation programs, which use a variety of proven techniques to help people quit. And because secondhand smoke can be harmful to your lungs, avoid being around people who are smoking.
Eat well. People with lung disease may lose weight both because it's uncomfortable to eat and because of the extra energy it takes to breathe. Yet a nutritionally rich diet that contains adequate calories is essential. Try to eat smaller meals more often during the day.
Aim to eat a variety of fruits and vegetables, whole grains, low-fat or fat-free dairy products, and lean meats. Avoid trans fat and saturated fat, too much salt, and added sugars. A dietitian can give you further guidelines for healthy eating.
- Get moving. Regular exercise can help you maintain your lung function and manage your stress. Aim to incorporate physical activity, such as walking or biking, into your daily routine. Talk to your doctor about which activities may be appropriate for you. If you require assistance with mobility over time, such as a wheelchair, look for activities or hobbies you can do that don't require walking.
- Take time to rest. Make sure to get enough rest. Taking time to rest can help you have more energy and cope with the stress of your condition.
- Get vaccinated. Respiratory infections can worsen symptoms of pulmonary fibrosis. Make sure you receive the pneumonia vaccine and an annual flu shot. It's important that your family members also be vaccinated. Aim to avoid crowds during flu season.
- Follow your treatment plan. You'll need to have ongoing treatment from your doctor. Follow your doctor's instructions, take your medications as prescribed, and adjust your diet and exercise as needed. Go to all of your doctor's appointments.
Coping and support
Pulmonary fibrosis is a chronic, progressive disease, meaning it worsens over time. Learning more about the disease can help you and your family cope. Attending pulmonary rehabilitation can help you manage your symptoms and improve your daily functioning.
Having pulmonary fibrosis can cause fear and stress. Spend time with family and friends and let them know how they can support and help you. Talk to your doctor about your condition and how you feel. If you're depressed, your doctor may recommend you see a mental health professional.
Participating in a support group with people who have pulmonary fibrosis may be helpful. It can help to talk to other people who have had similar symptoms or treatments and discuss coping strategies.
As your condition progresses, your doctor may advise you and your family to discuss end-of-life issues and plan advance directives.
Preparing for an appointment
If your primary care doctor suspects a serious lung problem, you're likely to be referred to a pulmonologist, a doctor who specializes in lung disorders.
What you can do
Before your appointment, you might want to write a list that answers the following questions:
- What are your symptoms and when did they start?
- Are you receiving treatment for any other medical conditions?
- What medications and supplements have you taken in the past five years?
- Do you smoke? If so, how much and for how long?
- What are all the occupations you've ever had, even if only for a few months?
- Do any members of your family have a chronic lung disease of any kind?
- Have you ever received chemotherapy or radiation treatments for cancer?
- Do you have any other medical conditions, especially arthritis?
You might also want to have a friend or family member accompany you to the appointment. Pulmonary fibrosis is a serious and complex disease. A friend or family member can provide emotional support and help remember information that you may have forgotten or missed. It is OK to take some notes.