Cryptogenic organizing pneumonia (COP) is a form of idiopathic interstitial pneumonia characterized by lung inflammation and scarring that obstructs the small airways and air sacs of the lungs (alveoli). Signs and symptoms may include flu-like symptoms such as cough, fever, malaise, fatigue and weight loss. COP often affects adults in midlife (40 to 60 years of age). The exact underlying cause of the condition is unknown (idiopathic). Treatment varies based on the severity of the condition but generally includes glucocorticoids.

Other forms of organizing pneumonia may result from infection (bacteria, viruses, parasites, or fungi); drugs; or a reaction to radiation therapy for breast cancer. Organizing pneumonia can also be associated with specific disorders such as certain connective tissue disorders, blood malignancies (cancers), or ulcerative colitis.

We are not aware of any familial cases of cryptogenic organizing pneumonia (COP) in the medical literature, and to our knowledge, there is no evidence that some people may be genetically predisposed to developing COP.

A diagnosis of cryptogenic organizing pneumonia is often suspected based on the presence of characteristic signs and symptoms once other conditions that cause similar features have been excluded. This includes ruling out other known causes of organizing pneumonia. Additional testing such as a computed tomography (CT) scan or lung biopsy can confirm the diagnosis.

The treatment of cryptogenic organizing pneumonia (COP) generally depends on the severity of the condition. For example, people who are mildly affected may simply be monitored as some cases can improve on their own. Unfortunately, the majority of people with COP have persistent and/or progressive symptoms that will require therapy. In these cases, oral or intravenous glucocorticoids can be given which often result in rapid improvement of symptoms.

The long-term outlook (prognosis) for people with cryptogenic organizing pneumonia (COP) is generally good. Approximately two-thirds of affected people recover after treatment with glucocorticoids. Unfortunately, a third of affected people experience persistent symptoms and/or abnormalities on pulmonary function testing. Rapidly fatal COP is uncommon.