Cryptogenic organising pneumonia (COP)

Cryptogenic organising pneumonia (COP) is a rare lung condition. It was previously called bronchiolitis obliterans organising pneumonia (BOOP).

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What is cryptogenic organising pneumonia?

Cryptogenic organising pneumonia (COP) is a rare lung condition and is a type of interstitial lung disease. It causes inflammation and scarring in the small airways (bronchioles) and air sacs (alveoli) in your lungs.

It was previously called bronchiolitis obliterans organising pneumonia (BOOP).

Cryptogenic – the cause is unknown

Organising pneumonia – inflammation in the airways and air sacs.

Although COP has pneumonia in its name, it is not an infection so it cannot be passed on.

Who’s at risk of cryptogenic organising pneumonia?

The condition is called cryptogenic because the cause is unknown. This can also be called idiopathic.

COP is more common in people with inflammatory conditions, such as:

What are the symptoms of cryptogenic organising pneumonia?

COP symptoms are similar to the symptoms of pneumonia. The most common symptoms of cryptogenic organising pneumonia are:

  • continuous dry cough
  • a high temperature – you might also sweat and shiver
  • feeling generally unwell
  • feeling short of breath
  • loss of appetite and losing weight.

Symptoms begin gradually, developing over a few weeks to months.

As the condition is rare, it may take some time to get a diagnosis. Your health care professional will want to rule out other causes first, including pneumonia or other conditions with pneumonia-like symptoms.

It is very important to rule out infections because treatment for cryptogenic organising pneumonia may make an infection worse.

How is cryptogenic organising pneumonia treated?

COP generally has a very good outlook, but it can take several weeks or months to make a full recovery. The length of treatment is different for everyone.

You will usually be given oral steroids, such as prednisolone, which are immunosuppressant drugs. In severe cases, you may be treated with a stronger steroid direct into the vein.

You’ll normally feel better in a few days. In most cases, you will notice an improvement within a week. Most people with COP will be treated for 6 to 12 months.

Some people get symptoms again when the steroid dose is reduced or stopped. If this happens, you may need to take further immunosuppressant drugs. It’s important once your treatment has ended to monitor any symptoms and get follow-up care from your doctor if needed.

What is immune suppression?

Our bodies fight infection with an immune response. Sometimes the immune response can be triggered even if there is no infection. It can also react too strongly to fighting an infection. This can cause damage to the body.

In these cases, immunosuppressant drugs are used to reduce the body’s immune response and prevent damage to the body. This is called immune suppression.

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