The signs and symptoms of pleurisy might include:

• Chest pain that worsens when you breathe, cough or sneeze
• Shortness of breath — because you are trying to minimize breathing in and out
• A cough — only in some cases
• A fever — only in some cases

Pain caused by pleurisy also might affect your shoulders or back.

In some cases of pleurisy, fluid builds up in the small space between the two layers of tissue (pleural space). This is called pleural effusion. When there is a fair amount of fluid, pleuritic pain lessens or disappears because the two layers of pleura are no longer in contact. A large amount of fluid in the pleural space can create pressure, compressing your lung to the point that it partially or completely collapses. This makes breathing difficult and might cause you to cough. The extra fluid can also become infected. This is called an empyema. An empyema is often accompanied by fever.

Two large, thin layers of tissue called pleura separate your lungs from your chest wall. One layer wraps around the outside of the lungs. The other layer lines the inner chest wall. Between these two layers is a small space (pleural space) that's usually filled with a very small amount of liquid. The layers act like two pieces of smooth satin gliding past each other, allowing your lungs to expand and contract when you breathe without any resistance from the lining of the chest wall.

Pleurisy occurs when the pleura becomes irritated and inflamed. As a result, the two layers of the pleural membrane rub against each other like two pieces of sandpaper, producing pain when you inhale and exhale. The pleuritic pain lessens or stops when you hold your breath.

Causes of pleurisy include:

• A viral infection, such as the flu (influenza)
• A bacterial infection, such as pneumonia
• A fungal infection
• Autoimmune disorder, such as rheumatoid arthritis
• Certain medications
• Lung cancer near the pleural surface
• Rib fracture
• Certain inherited diseases, such as sickle cell disease