Bronchitis is a condition in which the tissues lining the bronchi—the two main divisions of the airway that lead into the right and left lungs—become inflamed. Doctors define bronchitis as either acute, a temporary illness that clears up in three weeks or less; or chronic, a recurrent condition in which the person suffers coughing attacks for at least three months over two successive years. Chronic bronchitis is grouped together with emphysema as a form of chronic obstructive pulmonary disease (COPD).
Bronchitis can be caused by a wide range of disease organisms and other irritants that inflame the tissues of the bronchi, including viruses, bacteria, parasites, smoking, chemical pollutants, or dust particles. Acute
bronchitis is caused most often by viruses, while chronic bronchitis is caused most often by smoking.
In acute bronchitis, the tissues lining the bronchi become swollen and irritated by the disease organism or chemical. The air passages slowly become clogged by dead cells and leaking tissue fluid, which further irritates the bronchial tissues. The tissues begin to secrete mucus in response
to the inflammation. As the mucus accumulates in the airways, the person starts to cough in order to clear the breathing passages. The coughing, the sputum (mucus and other matter) that is brought up by coughing, and wheezing or shortness of breath are classic symptoms of acute bronchitis. Chest pain may develop after several days of severe coughing.
According to the National Center for Health Statistics, about 14 million Americans have chronic bronchitis. In an average year, there are 12–13 million cases of acute bronchitis reported in the United States, compared to 91 million cases of influenza, 66 million cases of the common cold, and 31 million cases of other acute upper respiratory infections. Acute bronchitis is more common in the winter months in most parts of the United States.
Children are more likely to develop acute bronchitis, while chronic bronchitis is largely a disease of adults. The male/female ratio for chronic bronchitis is about three to two. As far as is known, both acute and chronic bronchitis are equally common in all races and ethnic groups.
When to Call the Doctor about Bronchitis
Patients with acute bronchitis should start to feel better in about two weeks. They should call the doctor if their health does not improve by that time or if they have any of the following symptoms:
- Wheezing and coughing lasts longer than two weeks and is worse at night or during exercise.
- Coughing lasts longer than two weeks and brings up a bad-tasting fluid.
- In addition to coughing, the patients feels very weak and has a fever of 101°F (38.3°C) or higher that will not go down.
- Coughing brings up blood, rust-colored sputum, or yellowish or greenish matter.
- The patient has trouble breathing when lying down.
- The patient's feet swell.
Patients who have repeated episodes of acute bronchitis should see the doctor to be examined for chronic sinusitis or other illnesses. In addition, patients with congestive heart failure, asthma, or emphysema should see the doctor if they develop acute bronchitis, because other lung and heart disorders increase the risk of complications with acute bronchitis.
Some people are at increased risk of developing bronchitis:
- Smokers and people who live with smokers.
- People with gastroesophageal reflux disease (GERD). GERD is a condition in which stomach acid backs up into the esophagus, which can trigger the coughing reflex.
- People whose jobs expose them to chemicals, dust, or other substances that irritate the airway. These may include cotton and other textiles, wheat and other grains, ammonia, sulfur dioxide, chlorine, and a few other strong chemicals.
- People exposed to high levels of automobile exhaust.
- Infants, elderly people, and others with low resistance to infections.
The basic cause of bronchitis, whether acute or chronic, is a disease organism or substance that irritates the tissues lining the bronchi.
The symptoms of acute bronchitis are similar to those of a bad cold or other upper respiratory infection:
- Sore throat
- A feeling of tightness or congestion in the chest
- Overall feeling of tiredness
- Low-grade fever and chills
- Difficulty breathing
Acute bronchitis is essentially a diagnosis of exclusion, which means that the doctor must rule out such other illnesses as influenza, strep throat, pneumonia, whooping cough, or tonsillitis. The diagnosis is based on a combination of the patient's history, including a history of recent upper respiratory tract infections or exposure to others with such infections, and a physical examination. During the physical examination, the doctor will listen to the patient's breathing through a stethoscope. A chest x ray may be ordered to rule out pneumonia.
The doctor will sometimes collect a sample of the patient's sputum if there is reason to suspect that the bronchitis is caused by bacteria. Most cases of acute bronchitis are caused by the same types of virus that cause the common cold and cannot be treated with antibiotics; however, bacterial infections can be effectively treated by antibiotic medications. If the patient has a severe sore throat in addition to wheezing and coughing, the doctor may order a rapid strep test to rule out the possibility of strep throat, another type of bacterial infection.
If the patient has had several episodes of acute bronchitis or the doctor has other reasons for suspecting chronic bronchitis, the doctor will order pulmonary function tests (PFTs). These are tests in which the patient is asked to breathe into a device called a spirometer. The spirometer measures how much air the patient's lungs can hold and how fast the air moves in and out of the lungs. It can also be used to determine how well the lungs are exchanging oxygen and carbon dioxide. Another way the spirometer can be used is to test the effectiveness of inhaled medications in treating chronic bronchitis.
Acute bronchitis is usually treated at home with a combination of bed rest; over-the counter pain-relievers like aspirin, Advil, Tylenol, or Motrin to lower the fever; and over-the counter cough medications. Some of these medications (Robitussin, Mucinex) are intended to loosen the mucus in the bronchial passages while others (Benylin, Pertussin) are intended to suppress (quiet) the coughing. Patients should drink plenty of clear fluids to loosen the mucus and use a humidifier or cool-mist vaporizer to reduce the irritation in the bronchi.
Because the overuse of antibiotics can create drug-resistant organisms, the doctor may not prescribe an antibiotic for acute bronchitis unless he or she has test results indicating that the patient's illness is caused by a bacterium and not a virus.
People with chronic bronchitis may need stronger medications:
- Bronchodilators. Bronchodilators are drugs that work by opening up the airways, which allows for more efficient exchange of carbon dioxide and oxygen. Some are taken in tablet form while others are dispensed in inhalers.
- Steroids. This type of medication works by lowering the inflammation in the tissues lining the airways. These drugs can also be taken in pill form or through inhalers.
- Antibiotics. People with chronic bronchitis may be given antibiotics to lower the risk of developing complications.
- Oxygen. Patients who have severe attacks of chronic bronchitis may need to go to the hospital for oxygen therapy. There are also oxygen tanks that can be used in the home; some of these are portable units.
Most cases of acute bronchitis clear up completely in two to three weeks with no long-term complications. Chronic bronchitis, however, increases a person's risk of permanently weakened lungs, heart disease, and a shortened life span.
The best way to prevent chronic bronchitis is to quit smoking; parents can protect their children from bronchitis by quitting or by not smoking in the first place. In some cases, people whose jobs expose them to
chemicals, dust, or other materials that irritate the breathing passage may benefit from changing their occupation.
Acute bronchitis is more difficult to prevent because its most common cause is upper respiratory viruses that are hard to avoid. Regular hand washing and the use of hand sanitizers can reduce the spread of these viruses within a family, school, or day care center. Some people can lower the risk of bronchitis by getting annual flu shots. In addition, people who are over sixty-five or who have diabetes or emphysema may benefit from getting immunized against the most common cause of bacterial pneumonia.
Acute bronchitis is likely to continue to be a commonplace health problem because the viruses that are its most common cause are widespread, particularly during cold and flu season. Chronic bronchitis is expected to affect an even larger proportion of the adult population in the years ahead because many long-term smokers are now reaching the age at which the symptoms of chronic obstructive pulmonary disease are most likely to appear.
SEE ALSO Asthma; Common cold; Emphysema; Gastroesophageal reflux disease; Pneumonia; Smoking; Tonsillitus; Whooping cough
WORDS TO KNOW
Bronchus (plural, bronchi): One of the two major divisions of the airway that lead into the right and left lungs.
Diaphragm: A sheet of muscle tissue that divides the chest cavity from the abdominal cavity.
Spirometer: A device that is used to test the air capacity of a person's lungs and the amount of air that enters and leaves the lungs during breathing.
Sputum: Mucus coughed up from the respiratory tract.
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