Pleurisy, also known as pleuritis, is inflammation of the membranes that surround the lungs and line the chest cavity (pleurae). This can result in a sharp chest pain while 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 
bacterial infection, pneumonia, pulmonary embolism, autoimmune disorders, lung cancer, following heart surgery, pancreatitis 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, pulmonary embolism, and pneumothorax. Diagnostic testing may include a chest X-ray, electrocardiogram (ECG), and blood tests.Treatment depends on the underlying cause. Paracetamol (acetaminophen) and ibuprofen may be used to decrease pain. Incentive spirometry may be recommended to encourage larger breaths. About one million people are affected in the United States each year. Descriptions of the condition date from at least as early as 400 BC by Hippocrates. Signs and symptoms
The defining symptom of pleurisy is a sudden sharp, stabbing, burning or dull pain in the right or left side of the chest during breathing, especially when one inhales and exhales. It feels worse with deep breathing, coughing, sneezing, or laughing. The pain may stay in one place, or it may spread to the shoulder or back.
Bacterial infections associated with pneumonia and tuberculosis
Chest injuries (blunt or penetrating)
Familial Mediterranean fever, an inherited condition that often causes fever and swelling in the abdomen or the lungs
Fungal or parasitic infections
Heart surgery, especially coronary-artery bypass grafting
Cardiac problems (ischemia, pericarditis)
Inflammatory bowel disease
Lung cancer and lymphoma
Other lung diseases like cystic fibrosis, sarcoidosis, asbestosis, lymphangioleiomyomatosis, and mesothelioma
Pneumothorax
Pulmonary embolisms, which are blood clots that enter the lungsWhen the space between the pleurae starts to fill with fluid, as in pleural effusion, the chest pain can be eased but a shortness of breath can result, since the lungs need room to expand during breathing. Some cases of pleuritic chest pain are idiopathic, which means that the exact cause cannot be determined. Diagnosis
A diagnosis of pleurisy or another pleural condition is based on a medical history, physical examinations, and diagnostic tests. The goals are to rule out other sources of the symptoms and to find the cause of the pleurisy so that the underlying disorder can be treated. Physical examination
A doctor uses a stethoscope to listen to the breathing. This method detects any unusual sounds in the lungs. A person with pleurisy may have inflamed layers of the pleurae that make a rough, scratchy sound as they rub against each other during breathing. This is called pleural friction rub. Diagnostic tests
Depending on the results of the physical examination, diagnostic tests are sometimes performed. Chest x-ray
A chest X-ray takes a picture of the heart and lungs. It may show air or fluid in the pleural space.