A type of chest infection which is usually self-limitting in nature

It is a result of inflammation of the trachea and major bronchi and is therefore associated with oedematous large airways and the production of sputum.

The disease course usually resolves before 3 weeks, however, 25% of patients will still have a cough beyond this time.

Aetiology:

• Although there is uncertainty in the literature regarding the exact proportion of pathogens giving rise to acute bronchitis, it is accepted that viral infection is the leading cause.
• Around 80% of episodes occur in autumn or winter.

PC

• Cough: may or may not be productive (usually <30 days)
• sore throat
• rhinorrhoea
• wheeze

On examination:

• The majority of patients with have a normal chest examination, however, some patients may present with:
  • Low-grade fever
  • Wheeze

Differentiating acute bronchitis from pneumonia

• History: Sputum, wheeze, breathlessness may be absent in acute bronchitis whereas at least one tends to be present in pneumonia.
• Examination: No other focal chest signs (dullness to percussion, crepitations, bronchial breathing) in acute bronchitis other than wheeze. Moreover, systemic features (malaise, myalgia, and fever) may be absent in acute bronchitis, whereas they tend to be present in pneumonia.