What is idiopathic pulmonary fibrosis?

Idiopathic pulmonary fibrosis (IPF) is a progressive disease isolated to the lung. It is a type of interstitial lung disease, which is a group of 200 diseases with similar symptoms but different causes. In IPF, lung tissue becomes scarred. The scarring typically starts at the edges of the lungs and progresses towards the center of the lungs, making it more and more difficult for a person to breathe. Unfortunately, IPF is a disabling disease without a known cure or treatment.

What causes idiopathic pulmonary fibrosis?

The cause of IPF is unknown. In some patients the disease is genetic (you inherited the disease from your parents). Environmental factors (particularly exposure to certain types of dusts) may also play a role. What is known is that IPF changes the lung's ability to function normally. Typically, mild scarring of the lung tissue occurs first, but over months to years, the normal lung tissue is replaced by more heavily scarred lung tissue, which makes it difficult to breathe and deliver needed oxygen to the body.

Even though the cause of IPF is still being investigated, the following are considered to be risk factors for disease development:

  • Working around dust or fumes. Farmers, ranchers, hairdressers, stone cutters/polishers, and metal workers face a moderately increased risk of developing the disease due to exposure to these dusts or occupational fumes.
  • Age between 40 and 70 (approximately 2/3 of patients are older than 60 at the time of diagnosis)
  • History of smoking
  • Being male (more men are diagnosed with the disease than women)

Currently, more than 80,000 adults in the United States have IPF, and more than 30,000 new cases are diagnosed each year.

What are the symptoms of idiopathic pulmonary fibrosis?

Symptoms of IPF usually develop gradually and may not be noticed until the disease is well established. Symptoms include:

  • Dry cough
  • Shortness of breath, especially during or after physical activity
  • Lasting tiredness
  • Weight loss
  • Enlargement and bulb-like development of the fingertips and nails (a condition called clubbing)

Patients may also develop right sided heart failure with swelling of the legs. IPF affects each person differently and the disease progresses at varying rates.

How is idiopathic pulmonary fibrosis diagnosed?

First, your doctor will conduct a thorough medical history to rule out other lung-related illnesses or other medical causes. Next, he or she will conduct a physical examination. The physical exam is not specific enough to make the diagnosis of IPF, but it can aid in the diagnosis by identifying some telltale signs. The doctor will use a stethoscope to listen to your chest to determine if your lungs are producing any abnormal sounds when you breathe. He or she may then order one or more of the diagnostic tests or procedures shown in the chart.

What complications may occur?

Because lung tissue scarring results in an inability of the lungs to deliver needed oxygen to the body, strain is put on the right side of the heart. This may lead to high blood pressure in the lungs, a condition known as pulmonary hypertension. IPF is also associated with these potentially life-threatening conditions:

Diagnostic tests for idiopathic pulmonary fibrosis
Chest imaging studies Involves taking x-rays or high-resolution CT scans To rule out other diseases, allow for early and in some cases definitive diagnosis, assess extent of disease (changes in bronchial structure, scarring pattern throughout the lung)
Lung biopsy Involves taking a small sample of lung tissue typically by a small incision through the ribs with a thoracoscope To directly examine lung tissue to aid in the diagnosis of IPF for measuring disease activity, progression, and response to treatment
Pulmonary function test Involves using a device to measure breathing capacity To measure the degree of lung function impairment, monitor disease progression
Oxygen desaturation study Involves walking for almost six minutes while measuring the oxygen level through a probe attached to the finger or the forehead To determine the need for oxygen and monitor disease progression
Arterial blood test Involves measuring oxygen levels in the blood at rest To determine the lung's ability to move oxygen out to the body's tissues
Exercise test Involves using a treadmill or stationary bike To determine how well the heart and lungs respond to physical activity
Other laboratory tests Urinalysis, full blood count, differential blood count, urea measurement, electrolytes, creatinine levels, liver function tests, autoantibody tests To rule out other diseases, monitor changes in body functions over time

How is idiopathic pulmonary fibrosis treated?

There is no cure for IPF. The damage caused from the lung scarring cannot be reversed. In addition, disease progression cannot be predicted or halted. Current experimental treatments are aimed at slowing or halting disease progression.

Other medical/surgical treatments

The treatment of IPF is mainly supportive. You may need additional oxygen, supplied in a small portable oxygen tank, to help you breathe. Patients are also encouraged to be enrolled in an exercise program known as pulmonary rehabilitation to help them breathe better. Lung transplant surgery may be considered in some patients. This procedure is most often considered in patients less than 65 years of age who have advanced disease.

New medications under investigation

Despite the disappointment of current therapies, some exciting new treatments are currently under investigation. The Cleveland Clinic is one of 26 medical centers across the United States that excel in the treatment of IPF. These medical centers make up the IPFnet.

IPFnet is a network of research centers dedicated to the study of IPF. The network’s goal is to find effective therapies for patients with both the early and advanced stages of this devastating disease.

Please consult your doctor if you are interested in taking part in a clinical trial.

How often will I need to see my doctor?

Your health care providers will work with you to help you maintain the highest possible quality of life. Your initial visit will probably take place in your doctor's office. At times, you may need to go to the hospital for tests and treatments. You may need to see your doctor 3 to 4 times a year.

Where can I find out about support groups and other resources?

To learn more about your disease and other support services in your community contact:

American Lung Association
1301 Pennsylvania Ave. NW, Suite 800
Washington, DC 20004
T: 202.785.3355

Pulmonary Fibrosis Association
230 East Ohio Street, Suite 304
Chicago, Illinois 60611
T: 888.733.6741

Coalition for Pulmonary Fibrosis
10866 W. Washington Blvd #343
Culver City, CA 90232
(888) 222-8541

The Pulmonary Paper


  • Prendergast TJ, Ruoss SJ, Seeley EJ. Chapter 9. In: McPhee SJ, Hammer GD, eds. Pathophysiology of Disease. 6th ed. New York: McGraw-Hill; 2010. Pulmonary Disease. Accessed 9/3/2013.
  • King, TE. Chapter 261. In: Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson JL, Loscalzo J, eds. Harrison's Principles of Internal Medicine. 18th ed. New York: McGraw-Hill; 2012. Interstitial Lung Diseases. Accessed 9/3/2013.

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 9/3/2013…#10959