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What is cryptogenic organizing pneumonia (COP)?

Cryptogenic organizing pneumonia (COP), previously known as bronchiolitis obliterans with organizing pneumonia (BOOP), is a rare interstitial lung disease. It is a form of pneumonia in which the bronchioles (small airways), the alveoli (tiny air-exchange sacs), and the walls of the small bronchi become inflamed.

The condition is “cryptogenic” because the cause is unknown, and “organizing” because it is an unresolved pneumonia. COP is only diagnosed when all other possible causes of pneumonia have been eliminated. Should COP remain untreated, it can lead to severe lung damage and may require hospitalization.

Pulmonologists and thoracic surgeons who specialize in cryptogenic organizing pneumonia (COP) at the Brigham and Women’s Hospital Lung Center provide comprehensive, specialized care for patients experiencing COP. Their expertise and collaboration with other specialists throughout provides patients with a highly-informed diagnosis and a cohesive treatment plan.

What are risk factors for COP?

The cause of COP is unknown, and the average age of someone diagnosed is 50 to 60 years old. The risk of COP is higher in people with inflammatory diseases such as:

What are the symptoms of COP?

The symptoms of COP differ (depending on how much of the lung is affected) and typically resemble those of influenza (flu), such as:

  • Persistent, dry cough
  • High fever
  • Shaking and chills
  • Shortness of breath that worsens with exertion
  • Loss of energy and exhaustion
  • Weight loss
  • Difficulty breathing

In rare cases, patients may cough up blood and have chest pain, night sweats and joint pain.

How is COP diagnosed?

To diagnose COP, your doctor will carefully review your medical history, ask questions regarding your signs and symptoms and conduct a full physical examination. Symptoms and test results for COP typically resemble infectious pneumonia. COP is only diagnosed when your pneumonia symptoms do not improve with antibiotics and your blood and sputum cultures are negative.

Tests used to diagnose COP include:

What is the treatment for COP?

Treatment for COP depends on the severity of your condition. In mild cases, your physician will simply monitor your condition and it will improve on its own. The majority of cases require several weeks or months of corticosteroid therapy. Hospitalization and/or surgery may be necessary should your condition be particularly severe or should complications arise.

What medications are used to treat COP?

COP does not respond to antibiotic treatment, and instead oral or intravenous steroid therapy is usually required. Medication is typically administered over six to 12 months, as halting prematurely can cause the disease to return. Doctors usually prescribe:

  • Corticosteroids such as prednisone
  • Cytotoxic medications such as cyclophosphamide (typically used only when there is no improvement with corticosteroid treatment)

Additional medications may be prescribed to counteract side effects of the steroid. Recurrences are common. Your physician will continue to monitor you after treatment is concluded to ensure that you remain healthy.

What can you expect for COP care?

A multidisciplinary team will work with you every step of the way, from diagnosis through evaluation, to create a cohesive and comprehensive treatment plan. Our unique approach features same-day consultations with multiple specialists and fosters seamless, expert care. Your medical condition will be closely monitored and managed to promote optimal lung functioning and an improved quality of life.

Who treats COP?

Cryptogenic organizing pneumonia (COP) patients benefit from the wide range of specialists at The Lung Center, including thoracic surgeons, pulmonologists and imaging experts. This collaboration ensures comprehensive diagnosis and targeted treatment for patients.

Any recommended surgery or procedure will be performed by an experienced, board-certified surgeon, in collaboration with the treatment team including nurses and physician assistants, all of whom specialize in taking care of patients with COP.

How do I book an appointment of find directions?

What other resources can I find on COP?

Learn more about topics related to cryptogenic organizing pneumonia (COP) in our health library.

Visit the Kessler Health Education Library in the Bretholtz Center for Patients and Families to access computers and knowledgeable staff.

Access a complete directory of patient and family services.

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