empyema

When you breathe, your lungs take in oxygen from the air and deliver it to the bloodstream. The cells in your body need oxygen to work and grow. During a normal day, you breathe nearly 25,000 times. People with lung disease have difficulty breathing. Millions of people in the U.S. have lung disease. If all types of lung disease are lumped together, it is the number three killer in the United States.

The term lung disease refers to many disorders affecting the lungs, such as asthma, COPD, infections like influenza, pneumonia and tuberculosis, lung cancer, and many other breathing problems. Some lung diseases can lead to respiratory failure.

Dept. of Health and Human Services Office on Women's Health

Your pleura is a large, thin sheet of tissue that wraps around the outside of your lungs and lines the inside of your chest cavity. Between the layers of the pleura is a very thin space. Normally it's filled with a small amount of fluid. The fluid helps the two layers of the pleura glide smoothly past each other as your lungs breathe air in and out.

Disorders of the pleura include:

• Pleurisy - inflammation of the pleura that causes sharp pain with breathing
• Pleural effusion - excess fluid in the pleural space
• Pneumothorax - buildup of air or gas in the pleural space
• Hemothorax - buildup of blood in the pleural space

Many different conditions can cause pleural problems. Viral infection is the most common cause of pleurisy. The most common cause of pleural effusion is congestive heart failure. Lung diseases, like COPD, tuberculosis, and acute lung injury, cause pneumothorax. Injury to the chest is the most common cause of hemothorax. Treatment focuses on removing fluid, air, or blood from the pleural space, relieving symptoms, and treating the underlying condition.

NIH: National Heart, Lung, and Blood Institute