Pleural Effusion: Causes

Many different conditions can cause pleurisy and lead to pleural effusion. Viral infection is the most common cause. Other conditions that can cause pleurisy are:

• Bacterial infections like pneumonia and tuberculosis

• Autoimmune disorders like systemic lupus erythematosus and rheumatoid arthritis

• Lung cancer, including lymphoma

• Other lung diseases like sarcoidosis, asbestosis, lymphangioleiomyomatosis, and mesothelioma

• Pulmonary embolism, a blood clot in the blood vessels that go into the lungs

• Inflammatory bowel disease

• Familial Mediterranean fever, an inherited condition that often causes fever and swelling in the abdomen or lung

• Infection from a fungus or parasite

• Heart surgery, especially coronary artery bypass grafting

Other causes of pleurisy include:

• Chest injuries

• Reactions to certain medicines that can cause a condition similar to systemic lupus erythematosus. These medicines include procainamide, hydralazine, and isoniazid.

In some cases, doctors can't find the cause of the pleurisy. The most common cause of pleural effusion, or fluid in the pleural space, is congestive heart failure. Lung cancer, pneumonia, tuberculosis, and other lung infections also can cause swelling of the pleura and lead to a pleural effusion. Asbestosis, sarcoidosis, and reactions to some medicines also can lead to pleural swelling and pleural effusion.