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Genetic and Rare Diseases Information Center (GARD)

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Cryptogenic organizing pneumonia

Other Names for this Disease
  • COP
  • Idiopathic BOOP
  • Idiopathic bronchiolitis obliterans organizing pneumonia
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What is cyryptogenic organizing pneumonia?

What causes cryptogenic organizing pneumonia?

What is cyryptogenic organizing pneumonia?

Cryptogenic organizing pneumonia (COP) is a rapidly developing inflammatory lung disease characterized by flu-like symptoms including cough, fever, malaise, fatigue and weight loss. COP often affects adults in midlife (40 to 60 years of age). No predisposing factors have been identified and the cause is often unknown. Diagnosis may be made through computed tomography (CT) scan or lung biopsy. Response to treatment with corticosteroids is generally favorable.[1][2]
Last updated: 3/15/2013

What causes cryptogenic organizing pneumonia?

The underlying cause of cryptogenic organizing pneumonia (COP) is unknown (it is idiopathic). Organizing pneumonia is more specifically diagnosed as cryptogenic organizing pneumonia (COP) when, among other characteristics, no definite cause (such as infection or underlying tissue disease) for the condition is found. In other words, any known cause for the pneumonia must be ruled out before stating that organizing pneumonia is really cryptogenic.[3]

Other organizing pneumonias may result from infection (bacteria, viruses, parasites, or fungi); drugs; or a reaction to radiation therapy therapy for breast cancer. Organizing pneumonia also may occur in the specific context of specific disorders such as certain connective tissue disorders, ulcerative colitis, or after lung transplantation or bone marrow grafting.[3]
Last updated: 3/18/2013

  1. Cordier JF, Costabel U, du Bois R. Cryptogenic organizing pneumonia. Orphanet. 2004; Accessed 11/4/2011.
  2. King TE. Idiopathic Interstitial Pneumonias. The Merck Manual Home Health Handbook. 2008; Accessed 11/4/2011.
  3. Cordier JF. Cryptogenic organizing pneumonia. Clin Chest Med. December 2004; 25(4):727-738.