Diagnosing Idiopathic Pulmonary Fibrosis: What to Expect

Common Diagnostic Tests and Why Diagnosis Is Difficult

Female doctor showing patient and X-ray looking for idiopathic pulmonary fibrosis
Hero Images / Getty Images

Diagnosing idiopathic pulmonary fibrosis can be challenging, and the disease can both mimic and be mimicked by a number of other lung conditions. A high resolution CT scan is considered the diagnostic test of choice, though current guidelines recommend a surgical lung biopsy as well unless the diagnosis is extremely clear. Learn about when idiopathic pulmonary fibrosis may be suspected and other tests that are often performed.

Since the symptoms of idiopathic pulmonary fibrosis (IPF) mimic those of several heart and lung conditions, it often takes an extended period of time to diagnose the disease. During this period of time, frequently a year or two, patients often see several doctors in an attempt to find the reason for their symptoms. This can be very frustrating as a patient or as a family member of someone coping with the disease, and seeking support from friends and family as well as online communities of people with the disease is invaluable.

Common IPF Symptoms

Since a screening test for idiopathic pulmonary fibrosis is not currently available, the diagnosis if often first suspected due to respiratory symptoms. Like some other lung diseases, such as COPD, there is often significant damage to the lungs before symptoms related to idiopathic pulmonary fibrosis appear. These symptoms may include:

  • Shortness of breath, especially with activity: Shortness of breath is usually the first symptom, though when it occurs with activity, it may first be dismissed as something else or even thought to be only due to age. With time this breathing difficulty worsens so that shortness of breath occurs even at rest.
  • A persistent cough which is usually dry (non-productive)
  • Shallow, rapid breathing
  • Fatigue
  • Losing weight without trying (unexplained weight loss)
  • Clubbing: Clubbing is a condition in which the fingers and toes become enlarged at the end, resembling an upside-down spoon.
  • Muscle and joint aches

Screening for IPF

While a screening test for idiopathic pulmonary fibrosis is not available, the technique for screening for lung cancer, may pick up IPF in some people for who screening is approved and recommended.

Diagnosis and Staging

The diagnosis of IPF often takes some time, with many people going a year or two and seeing multiple physicians before the diagnosis is made. The reason for this is that the early symptoms of IPF closely mimic those for many other conditions, including heart disease. Many people undergo an extensive cardiac workup before being diagnosed based on common initial symptoms.

Some tests your doctor may order include:

  • High-resolution CT Scan: IPF is usually diagnosed based on typical findings seen on a high-resolution CT scan of the chest. On a CT scan, the fibrosis in the lungs appears in what radiologists refer to as a honeycombed pattern.
  • Lung biopsy: There are times when a CT scan alone may strongly suggest the diagnosis of IPF, but according to recent guidelines, a lung biopsy is recommended. This may be done as part of a bronchoscopy, through a small incision in the chest (thoracoscopy) or by a thoracotomy. The biopsy is done primarily to rule out other potential causes of lung disease such as lung cancer or sarcoidosis.
  • Other tests that aid in diagnosis and staging: A combination of an exam and other tests are usually done both to aid in diagnosis, determine how well the lungs are functioning, and to figure out how far the disease has advanced. Some of these include:
  • A thorough history and physical exam
  • Spirometry: Spirometry is a test that determines how much air is forcefully exhaled over a period of one second, and is an indication of lung function.
  • Other pulmonary function tests
  • Oximetry
  • Arterial blood gases: Both oximetry and ABG's are done to evaluate the oxygen content of the blood.
  • Testing for tuberculosis
  • Blood tests: Research is looking into biomarkers which will help to diagnosed the disease in the future. Currently, tests to rule out connective tissue disease are recommended as part of the diagnostic work-up.
  • Genetic Predisposition: Idiopathic pulmonary fibrosis may run in families and certain mutations (on chromosome 11) have been found to be common in familial IPF.

Differential Diagnosis

There are several conditions that can mimic idiopathic pulmonary fibrosis, both in the symptoms they cause, and findings that are seen on imaging studies. Some of these include:

  • Asbestosis
  • Hypersensitivity pneumonitis
  • Other interstitial pneumonias
  • Connective tissue disease
  • Drug-related lung disease
  • Radiation-related lung disease

A Word From Verywell

If you have been diagnosed or are concerned that you may have idiopathic pulmonary fibrosis it's important to know that there are treatment options available, and more are being researched and developed. Like many areas of medicine, advances in the management of idiopathic pulmonary fibrosis are happening rapidly, and not all doctors may be up-to-date on the latest treatments. Getting a second opinion, preferably with a physician who specializes in idiopathic pulmonary fibrosis could make a difference both in your outcome and your quality of life with the disease.

Along with taking control of certain lifestyle factors, you can continue to live well with idiopathic pulmonary fibrosis.

Was this page helpful?

Article Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Raghu G, Remy-Jardin M, Myers JL, et al. Diagnosis of Idiopathic Pulmonary Fibrosis. An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline. American Journal of Respiratory and Critical Care Medicine. 2018. 198(5):e44-e68. doi:10.1164/rccm.201807-1255ST

Additional Reading