When you breathe normally, the lungs expand and contract easily and rhythmically inside your rib cage. Each lung is enclosed in a moist, smooth, two-layered membrane, which is called a pleura. The pleura lubricates the moving parts of the lungs and makes breathing easier. The outer layer of the pleura lines the rib cage. Between the two thin layers is a virtually imperceptible space, which is called the pleural space. It permits the layers to glide gently across each other. If either of your pleura becomes inflamed and roughened because of an infection, this seriously impedes the movement of the layers, and you have pleurisy.

Pleurisy is actually a symptom of an underlying disease rather than a disease in itself. The pleurae may become inflamed as a complication of a lung or chest infection such as pneumonia or tuberculosis sleep into the pleural space. This causes a condition called pleural effusion. But pleurisy is not the only cause of pleural effusion; the condition may also be a complication of a generalized disease such as rheumatoid arthritis a liver or kidney disorder, or heart failure . Cancer cells that are spreading from a tumor in the lungs, breast, or ovaries can also cause pleural effusion.

What are the Symptoms?

If you have pleurisy, it hurts to breathe deeply or cough. You may also have severe, but one-sided, chest pain. These symptoms are accompanied by others that are associated with the underlying disorder. The pain will disappear if pleural effusion occurs as a result of pleurisy, because fluid will prevent the roughened or inflamed layers of the pleura from rubbing against each other. If this happens, you may become breathless.

What are the Risks?

Pleurisy and pleural effusion due to infection have become rare disorders. This is because they now can be very effectively treated with antibiotics. Pleurisy is four times as common as pleural effusion.

In most cases the risks of pleurisy are the same as the risks associated with the underlying cause. Advanced pleural effusion can compress the lungs and cause severe breathlessness. Pleural effusion may also lead to empyema .

What Should be Done?

Consult your physician if breathing becomes painful, you seem unusually short of breath, and either or both of these symptoms is accompanied by a fever, no matter how slight. After questioning you about symptoms and previous illness, the physician will probably listen to your chest with a stethoscope and will percuss, or finger tap, your chest while listening for characteristic sounds made by irritated pleurae and pleural effusion. You may need a chest X-ray to help determine what disorder has caused the pleurisy. If you have pleural effusion, one way to diagnose the cause is to study the composition of the fluid, so a sample of fluid may be taken from the pleural space, with a needle and syringe.

What is the Treatment?

Because pleurisy and pleural effusion are symptoms of other disorders, the only way to cure them is to treat the underlying disease. Meanwhile, to ease chest pains, the doctor may recommend that you use an analgesic such as aspirin.