Pleurisy, also known as pleuritis, is the inflammation of the membranes that surround the lungs and line the chest cavity (pleurae).

This can result in a sharp chest pain with breathing. Occasionally the pain may be a constant dull ache. Other symptoms may include shortness of breath, cough, fever or weight loss, depending on the underlying cause.

The most common cause is a viral infection. Other causes include pneumonia, pulmonary embolism, autoimmune disorders, lung cancer, following heart surgery, pancreatitis, chest trauma, and asbestosis.

Occasionally the cause remains unknown. The underlying mechanism involves the rubbing together of the pleurae instead of smooth gliding. Other conditions that can produce similar symptoms include pericarditis, heart attack, cholecystitis, and pneumothorax. Diagnosis may include a chest X-ray, electrocardiogram and blood tests.

Treatment depends on the underlying cause. Paracetamol and ibuprofen may be used to decrease pain. Incentive spirometry may be recommended to encourage larger breaths.

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