Asthma

Asthma is a disease in which inflammation of the airways causes airflow into and out of the lungs to be restricted. When an asthma attack occurs, the muscles of the bronchial tree become tight and the lining of the air passages swells, reducing airflow and producing the characteristic wheezing sound. Mucus production is increased.

Most people with asthma have periodic wheezing attacks separated by symptom-free periods. Some asthmatics have chronic shortness of breath with episodes of increased shortness of breath. Other asthmatics may have cough as their predominant symptom. Asthma attacks can last minutes to days, and can become dangerous if the airflow becomes severely restricted.

Bronchiole under asthma attack

Bronchitis

Acute bronchitis is generally caused by viral respiratory infections and typically appears just as the symptoms of the initial infection are waning. These viral infections may be caused by any number of respiratory viruses including the rhinoviruses which cause the common cold . These viruses produce bronchial inflammation which sets the stage for bronchitis and, in some cases, a secondary bacterial infection. Early symptoms may include a tickle deep in the throat just above the sternal notch which progresses into an irritating dry cough .

Chronic Bronchitis

Bronchitis is an inflammation of the main air passages to the lungs. Bronchitis may be sudden (acute) and short-lived, or chronic, meaning that it lasts a long time and often recurs. To be classified as chronic, you must have a cough with mucus most days of the month for three months out of the year. Chronic bronchitis is a long-term condition of excessive mucus with a productive cough . This ongoing condition is inflammation but not infection. It blocks air flow in and out of the lungs.

Chronic bronchitis, like emphysema, is also known as chronic obstructive pulmonary disease . As these lung conditions progress over time, you become increasingly short of breath, have difficulty walking or exerting yourself physically, and may need oxygen on a regular basis.

Cigarette smoke is the chief cause of chronic bronchitis, including long-term exposure to second-hand smoke.

Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) refers to chronic lung disorders that result in blocked air flow in the lungs. The two main COPD disorders are emphysema and chronic bronchitis, the most common causes of respiratory failure. Emphysema occurs when the walls between the lung's air sacs become weakened and collapse. Damage from COPD is usually permanent and irreversible.

Emphysema

Emphysema is a lung disease that involves damage to the air sacs (alveoli). The air sacs are unable to completely deflate (hyperinflation) and are therefore unable to fill with fresh air to ensure adequate oxygen supply to the body. Cigarette smoking is the most common cause of emphysema. Tobacco smoke and other pollutants are thought to cause the release of chemicals from within the lungs that damage the walls of the air sacs. This damage becomes worse over time, affecting the exchange of oxygen and carbon dioxide in the lungs.

Sarcoidosis

Sarcoidosis is a disease of unknown cause in which inflammation occurs in the lymph nodes, lungs, liver, eyes, skin, and/or other tissues. The cause of the disease is unknown. Tissue samples from affected organs show clusters of immune cells (macrophages, lymphocytes, and multinucleated giant cells). These clusters are called granulomas.

Possible causes include a hypersensitive response to some factor in the environment, a genetic predisposition, or an extreme immune response to infection. The incidence varies widely according to race and sex.

The disease is most common among North Americans of African heritage and Northern European Caucasians. Women of African heritage are affected more than men of African heritage. The onset of the disease usually occurs in people between 30 and 50 years old. Sarcoidosis is very rare in young children.

Pneumonia

Pneumonia is an inflammation of the lungs caused by an infection. Many different organisms can cause it, including bacteria, viruses, and fungi. It is a common illness that affects millions of people each year in the United States. Pneumonia can range from mild to severe, even fatal. The severity depends on the type of organism causing pneumonia as well as your age and underlying health.

Turberculosis

Tuberculosis can develop after inhaling droplets sprayed into the air from a cough or sneeze by someone infected with Mycobacterium tuberculosis. The disease is characterized by the development of granulomas (granular tumors) in the infected tissues.

The usual site of the disease is the lungs, but other organs may be involved. The primary stage of the infection is usually asymptomatic . In the United States, the majority of people will recover from primary TB infection without further evidence of the disease.

Pulmonary TB develops in the minority of people whose immune systems do not successfully contain the primary infection. The disease may occur within weeks after the primary infection, or it may lie dormant for years before causing disease.