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Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis, or IPF, is a condition that causes progressive scarring of the lungs. Fibrous scar tissue builds up in the lungs over time, affecting their ability to provide the body with enough oxygen. The cause of the condition is unknown.

IPF affects more than 100,000 people in the United States, with 30,000 to 40,000 new cases diagnosed each year. Typically the disease is found in people between the ages of 50 and 70 and affects men more frequently than women. Most patients are former smokers. There are no proven risk factors for IPF, but a minority of patients have a family history of lung scarring.

Symptoms of IPF often appear gradually and include:

  • Shortness of breath, particularly during or after physical activity
  • Chronic, dry hacking cough
  • Crackle sound in the lungs heard through a stethoscope
  • Rounding of the fingernails, a condition called clubbing

Symptoms of IPF may mimic those of other diseases that cause lung scarring, so diagnosing IPF often involves ruling out other conditions. Several visits with your doctor may be needed to finalize your diagnosis and treatment approach.

Diagnosing idiopathic pulmonary fibrosis requires input from pulmonologists, radiologists and, in many cases, pathologists experienced in evaluating patients with interstitial lung disease. A face-to-face discussion among these various specialists is often necessary to make an accurate diagnosis.

To determine if you have IPF, your doctor will start by conducting a thorough medical history and physical examination. The medical history will include discussing other medical problems you have that could be related to lung scarring, such as connective tissue diseases, and reviewing any medications you're taking. The physical exam will include listening to your chest with a stethoscope to check for a crackling sound and carefully examining your skin and joints.

In addition to a thorough medical history and physical exam, your doctor may conduct the following tests:

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Unfortunately, there is currently no cure for idiopathic pulmonary fibrosis, and there is no proven medication therapy to treat it. Medical studies suggest a potential role for several therapies, listed below, but further study is needed.

  • Pirfenidone — Data from three large clinical trials of pirfenidone have suggested a benefit in IPF. Pirfenidone appears to slow the rate of decline in lung function by a small amount. This drug is not currently approved for use in the United States but further studies are underway.
  • Acetylcysteine (NAC) — Data from a large study adding acetylcysteine to traditional medication therapies that include prednisone suggest it may help, but there's no consensus on whether or not the results are definitive. Acetylcysteine is available over the counter at most pharmacies and stores that carry supplements.
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Reviewed by health care specialists at UCSF Medical Center.

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Interstitial Lung Disease Program
400 Parnassus Ave., Fifth Floor
San Francisco, CA 94143
Phone: (415) 353-2577
Fax: (415) 353-2568
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