Bronchitis is an inflammation of the lining of your bronchial tubes, which carry air to and from your lungs. People who have bronchitis often cough up thickened mucus, which can be discolored. Bronchitis may be either acute or chronic.
Often developing from a cold or other respiratory infection, acute bronchitis is very common. Chronic bronchitis, a more serious condition, is a constant irritation or inflammation of the lining of the bronchial tubes, often due to smoking.

Symptoms

• Cough
• Production of mucus (sputum), which can be clear, white, yellowish-gray or green in color — rarely, it may be streaked with blood
• Fatigue
• Shortness of breath
• Slight fever and chills
• Chest discomfort

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow from the lungs. Symptoms include breathing difficulty, cough, mucus (sputum) production and wheezing. It's typically caused by long-term exposure to irritating gases or particulate matter, most often from cigarette smoke. People with COPD are at increased risk of developing heart disease, lung cancer and a variety of other conditions.
A group of lung diseases that block airflow and make it difficult to breathe.
Emphysema and chronic bronchitis are the most common conditions that make up COPD. Damage to the lungs from COPD can't be reversed.
Symptoms include shortness of breath, wheezing, or a chronic cough.
Rescue inhalers and inhaled or oral steroids can help control symptoms and minimize further damage.
Emphysema and chronic bronchitis are the two most common conditions that contribute to COPD. These two conditions usually occur together and can vary in severity among individuals with COPD.

Interstitial (in-tur-STISH-ul) lung disease describes a large group of disorders, most of which cause progressive scarring of lung tissue. The scarring associated with interstitial lung disease eventually affects your ability to breathe and get enough oxygen into your bloodstream.
Interstitial lung disease can be caused by long-term exposure to hazardous materials, such as asbestos. Some types of autoimmune diseases, such as rheumatoid arthritis, also can cause interstitial lung disease. In some cases, however, the causes remain unknown.

Symptoms

• Shortness of breath at rest or aggravated by exertion
• Dry cough

Pneumonia is an infection that inflames the air sacs in one or both lungs. The air sacs may fill with fluid or pus (purulent material), causing cough with phlegm or pus, fever, chills, and difficulty breathing. A variety of organisms, including bacteria, viruses and fungi, can cause pneumonia.
Pneumonia can range in seriousness from mild to life-threatening. It is most serious for infants and young children, people older than age 65, and people with health problems or weakened immune systems.

Symptoms

• Chest pain when you breathe or cough
• Confusion or changes in mental awareness (in adults age 65 and older)
• Cough, which may produce phlegm
• Fatigue
• Fever, sweating and shaking chills

The pleura is the membrane that lines the thoracic (chest) cavity and covers the lungs. It is like a large sheet of tissue that wraps around the outside of the lungs and lines the inside of the chest cavity. There are several types of pleural diseases, including:
Pleurisy - an infection of the pleural cavity
Pleural effusion - the buildup of pleural fluid in the pleural cavity
Pneumothorax - the presence of air or gas in the pleural cavity
Hemothorax - the presence of blood in the pleural cavity
Pleural tumors

Symptoms

• Shortness of breath
• A cough
• Fever and chills
• Rapid, shallow breathing
• Unexplained weight loss

Tuberculosis (TB) is a potentially serious infectious disease that mainly affects the lungs. The bacteria that cause tuberculosis are spread from person to person through tiny droplets released into the air via coughs and sneezes.
Once rare in developed countries, tuberculosis infections began increasing in 1985, partly because of the emergence of HIV, the virus that causes AIDS. HIV weakens a person's immune system, so it can't fight the TB germs. In the United States, because of stronger control programs, tuberculosis began to decrease again in 1993. But it remains a concern.

Symptoms

• Latent TB. You have a TB infection, but the bacteria in your body are inactive and cause no symptoms. Latent TB, also called inactive TB or TB infection, isn't contagious. Latent TB can turn into active TB, so treatment is important.
• Active TB. Also called TB disease, this condition makes you sick and, in most cases, can spread to others. It can occur weeks or years after infection with the TB bacteria.

Sleep apnea is a potentially serious sleep disorder in which breathing repeatedly stops and starts. If you snore loudly and feel tired even after a full night's sleep, you might have sleep apnea.

Symptoms

• Loud snoring
• Episodes in which you stop breathing during sleep — which would be reported by another person
• Gasping for air during sleep
• Awakening with a dry mouth
• Morning headache
• Difficulty staying asleep (insomnia)
• Excessive daytime sleepiness (hypersomnia)