Bronchitis

Bronchitis is an inflammation of the lining of the large air passages in the lungs, called bronchial tubes or bronchi. The bronchi connect the trachea (windpipe) to the lungs. This inflammation typically causes phlegm and a cough.


Causes/associated factors
There are two types of bronchitis: acute and chronic. In the United States, both types of bronchitis are very common. Chronic bronchitis affects about 5 percent of the population.
Acute bronchitis develops rapidly over the course of a few days, usually in response to a respiratory virus or bacterial infection. Less commonly, acute bronchitis can develop as a result of respiratory exposure to irritating chemicals, dusts or fumes. Bronchitis can also develop when acid from your stomach comes up into your airways and causes damage.

Typical symptoms are a dry cough that later becomes productive (filled with phlegm). The condition is most prevalent in winter and often occurs during or after a cold. Acute bronchitis usually goes away within two to three weeks. The focus of bronchitis treatment is primarily to manage symptoms and provide comfort.

Chronic bronchitis develops gradually over the course of weeks, months or even years, with continuous inflammation and thickening of the tissues lining the bronchial tubes. Chronic bronchitis is usually related to prolonged exposure to cigarette smoke, but may also be caused by air pollution or industrial dusts and fumes. Sometimes, it develops as a complication of repeated bacterial or viral infections (for example, recurrent attacks of acute bronchitis).

Chronic bronchitis is characterized by a daily production of excessive quantities of mucus that is not adequately cleared from the airways. The condition is continuous over a period of years, which causes lung congestion, coughing and difficulty breathing. The severity of the condition depends on how long and how much you've been exposed to smoke or inhaled other chemicals.

Along with emphysema, chronic bronchitis is considered a chronic obstructive pulmonary disease (COPD). With COPD, lung function is significantly reduced. This causes difficulty breathing, especially during exertion. Although chronic bronchitis doesn't typically cause severe COPD, it can in advanced cases.

People who have weak immune systems or a lung disease or those who've had a recent illness, especially a respiratory condition, have a higher risk of developing bronchitis.


Signs/symptoms
Symptoms of acute bronchitis typically follow a respiratory infection and may include:
a dry cough that later produces phlegm, which may be discolored
fever, usually less than 101°F
sore throat
wheezing or shortness of breath
pain or a burning sensation in the chest, which often worsens during a coughing spell
coughing up blood (usually minor with blood-streaked mucus)
chills
fatigue
People who have chronic bronchitis typically have a history of cigarette smoking. Symptoms often include:

persistent cough with phlegm that's usually worse in the morning
shortness of breath that may come and go
shortness of breath on exertion
coughing spasms
frequent respiratory infections
wheezing
in later stages, symptoms of heart failure, such as needing to sit up to breathe and swelling of the legs

Diagnosis
The doctor will ask questions about your medical and work history and do a physical exam. The doctor will place a special emphasis on the lung exam. To help the doctor determine the extent of the problem and rule out other possibilities such as pneumonia, you may also need diagnostic tests. Depending on the circumstances, you may need a chest X-ray, sputum culture, lung function tests and blood tests. The diagnosis of bronchitis is based on clinical characteristics rather than any one specific test.
To be diagnosed with chronic bronchitis, you must have a productive cough most days of the month for at least three months a year, two years in a row, without another underlying condition to blame, such as heart disease, tuberculosis or cancer. If you're diagnosed with chronic bronchitis, consultation with a specialist (such as a pulmonologist) may be recommended.

People who have repeated episodes of bronchitis are typically evaluated for other related problems, such as:

asthma
inflammation of the sinuses or tonsils
conditions such as gastroesophageal reflux disease (a chronic condition in which the lower esophageal sphincter, the valve between the bottom of the esophagus and the top of the stomach, allows stomach acid to flow backward into the esophagus)

Treatment
Acute bronchitis
If you have acute bronchitis, your doctor will recommend getting plenty of rest and avoiding cigarette smoke and other respiratory irritants, such as air pollution, dust and fumes. If you smoke, it's important to quit.

Drinking plenty of fluids can help loosen up the phlegm. Your doctor may also recommend over-the-counter fever-reducing products, as well as cough suppressants, expectorants or prescription bronchodilators (medication that expands the bronchial tubes).

If the infection is thought to be bacterial, your doctor may prescribe antibiotics. Remember, most cases of bronchitis are caused by viral infections, however. Antibiotics are not effective for viral infections.

For bronchitis caused by the flu virus, treatment with an antiviral medication may be helpful. It should begin within the first 48 hours of illness, however.

Chronic bronchitis
If you have chronic bronchitis, it's important to avoid cigarette smoke. If you smoke, quit. It's also helpful to avoid areas with heavy air pollution, fumes or dust, as well as avoid contact with anyone who has a cold or the flu.

Dress properly for the weather, and get the pneumococcal vaccine as well as an annual flu shot, unless your doctor tells you otherwise. A regular exercise program and a well-balanced diet may also be recommended.

Treat respiratory infections and coughing and wheezing spells promptly, and avoid exposure to anything that may cause an allergic reaction.

Keep your sputum loose by drinking adequate fluids and humidifying the air. Your doctor may teach you how to increase sputum drainage by coughing and tapping on your chest. To maximize lung function, the doctor may also prescribe antibiotics, oxygen therapy, bronchodilators and possibly steroids.

Finally, your doctor may recommend a pulmonary rehabilitation course to help you learn how to manage your illness.


Complications
The most common complication of acute bronchitis is postbronchitic cough. This cough usually resolves in about one to three months, but can last up to six months. The cough is commonly treated with bronchodilator treatment (the same treatment used for asthma attacks). Some people may ultimately develop asthma after a bronchitis illness.
People who have chronic bronchitis can have sudden worsening spells known as acute exacerbations of chronic bronchitis. Symptoms often include increased production or change in the character of phlegm, shortness of breath, increased severity of cough and respiratory distress.

Other complications of chronic bronchitis may include recurrent pneumonia (a lung infection), advanced chronic obstructive pulmonary disease and cardiovascular problems. In severe cases, respiratory failure can be fatal. If you smoke and don't quit, your life expectancy will decrease.


Pregnancy-specific information
Acute bronchitis in a healthy pregnant woman is usually harmless for the developing baby. Most medications used to reduce symptoms of bronchitis are safe to use during pregnancy, but always check with your doctor first. Chronic bronchitis is rare in women of childbearing age, but it can be serious if it's severe enough to reduce oxygen delivery to the baby. To reduce the risk of complications, never smoke during pregnancy.

Senior-specific information
Chronic bronchitis is more common in older adults. If you smoke, quitting is the most important step you can take to prevent the problem from worsening. Prompt medical treatment of respiratory infections can help prevent complications. If you have a chronic heart or lung problem, seek prompt medical treatment if you develop symptoms of acute bronchitis.

Prevention
To prevent both acute and chronic bronchitis:
If you smoke, quit.

Avoid secondhand smoke and irritating environmental fumes and pollutants.

If you work with chemicals, dusts or other respiratory irritants, wear appropriate protective equipment, such as a respirator.

Wash your hands often.

Avoid exposure to anyone who has a cold or the flu.

If you develop a cold or the flu, get plenty of rest and take good care of yourself.

Review your immunization needs with your doctor. Vaccination against Pneumococcus pneumoniae and yearly flu shots may be recommended to minimize flare-ups from chronic bronchitis.

Control any individual risk factors, such as gastroesophageal reflux disease, aspiration problems or asthma.