Acute Bronchitis

Lungs	Respiratory system	Bronchitis	Lung anatomy

Definition   

An inflammation of the main air passages to the lungs (the bronchi).

Causes and risks   

Bronchitis generally follows a viral respiratory infection and typically appears just as the symptoms of the initial infection are waning. The viral infection, which may be caused by any number of respiratory viruses including the rhinoviruses which cause the common cold, produces 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. As the infection progresses the cough may become productive with thick yellow sputum (purulent sputum) which is very rarely blood streaked. Associated symptoms may include fever, malaise, chest pain and shortness of breath.

Infants generally develop other respiratory complications such as bronchiolitis or pneumonia while older children and adolescents develop typical adult symptoms of bronchitis.

Risk factors include recent illnesses that have lowered resistance to infection, a preceding viral respiratory infection or chronic pulmonary problems. The incidence is 4 out of 100 people.

Prevention   

Minimize exposure to cold, damp environments which, combined with air pollution, may make people more susceptible to bronchitis.

Symptoms   

• cough
  • may produce pus-like sputum or mucous-like sputum
  • may have episodes of coughing up blood (blood streaked sputum)
  • lasting for less than 6 weeks
• shortness of breath
• may cause the individual to awaken at night (paroxysmal nocturnal dyspnea)
• wheezing
• rales
• rattle in chest
• general ill feeling (malaise)
• slight fever
• sore throat
• chest pain, soreness, and constricted feeling in the chest
• chills (uncommon)

Signs and tests   

A physical examination confirms the symptoms.

Tests performed may include:

• a chest X-ray to determine if pneumonia has developed
• a sputum culture to determine if the inflammation is caused by bacteria

Treatment   

The goal of treatment is to relieve the symptoms with medications and supportive measures.

Bronchodilators such as albuterol may be prescribed to open constricted air passages. In otherwise healthy people, antibiotics are rarely needed and are only used if the sputum becomes yellow, gray or green. Decongestants also help alleviate the symptoms of bronchitis. Medications that liquefy mucus secretions (mucolytics) may also be prescribed.

Supportive measures include rest, increased humidity (using a cool mist humidifier) to soothe air passages, and increased fluid intake to maintain hydration and to thin respiratory secretions.

Prognosis   

Symptoms usually abate within 7 to 10 days in the absence of prior chronic pulmonary disease.