What Happens
Acute
bronchitis is inflammation of the tubes that carry air to the lungs
(bronchial tubes). It is usually caused by a virus and follows an
upper respiratory tract infection such as a cold or
influenza (flu). The infection moves from the nose,
mouth, and throat to the bronchial tubes, causing the tubes to swell and mucus
production to increase.
At first, a dry, hacking cough is
present. After a few days, the cough may bring up mucus from the lungs. The
swollen tubes and increase in mucus may make it more difficult for you to
breathe.
See an illustration of
acute
bronchitis
.
Most cases of acute bronchitis in otherwise
healthy people last only 2 to 3 weeks. However, more than 20% of people with
acute bronchitis have a cough that lasts more than 4 weeks.2
How soon you get better depends on several
things, including:
- Your age and health.
- The organism
causing the infection. Acute bronchitis from a
viral cause is usually less severe than from a
bacterial cause.
- Whether you smoke.
Complications
Most people get better without
developing complications. If complications occur, they include:
- Pneumonia.
Acute bronchitis that gets worse (increased fatigue, high fever, chest pain,
and increased shortness of breath) usually indicates that pneumonia has
developed.
- Repeated episodes of bacterial acute bronchitis. This
condition commonly occurs in people who smoke and in people with immune system
problems, such as
HIV infection,
cystic fibrosis, and cancer.
If you have a long-term (chronic) respiratory disease,
such as
asthma, acute bronchitis can lead to worsening of your
coughing and wheezing and can increase the risk of developing complications. In
this case, acute bronchitis is a more serious problem and may be treated
differently.
Children and older adults are most at risk for
complications.
Children who have repeated bouts of acute bronchitis
need to be evaluated to see whether they may have a foreign object in the air
passage. Children may also be evaluated for asthma or other respiratory tract
problems, such as:
- Cystic
fibrosis, an inherited disease that results in the production of thick
mucus in the lungs.
- Bronchiectasis, a lung condition in
which the airways of the lungs are damaged, get bigger, and are frequently
infected. A common symptom is a cough that brings up mucus.
- Allergies, which are an
immune system reaction to usually harmless substances.
Symptoms include cough and difficulty breathing.
Allergic rhinitis (hay fever) is a common
allergy.
- Sinusitis, an infection of the
mucous membranes that line the inside of the nose and
facial sinuses. Symptoms include pain and a chronic cough that produces
mucus.
- Adenoiditis, an inflammation of the
adenoids
, which are small masses of tissue at the back
of the nose and throat.