Acute Bronchitis

- Cough in the absence of fever, tachypnea, and tachycardia suggests bronchitis rather than pneumonia.

- Acute bronchitis in adults and children is almost exclusively viral in etiology (≥ 90%).

- Respiratory syncytial virus is a significant pathogen in adults with acute bronchitis, especially elderly.

- Mycoplasma pneumoniae and Chlamydia pneumoniae have been implicated but not fully established as pathogens in acute bronchitis. Empiric therapy for these organisms is not recommended.

- Prolonged cough (>3 weeks) is not unusual in acute viral bronchitis (45% of patients still coughing at 2 weeks and 25% after 3 weeks). NB: Pertussis may mimic acute bronchitis and is underdiagnosed. Investigate if persistent cough (≥ 6 days), especially if associated with vomiting.

- Postnasal drip, asthma, and GERD account for > 75% of coughs lasting at least 3 weeks with negative chest x-ray.

- Purulent (green/yellow) sputum production is indicative of inflammatory reaction and does not necessarily imply bacterial infection.

- In most patients the respiratory exam is normal (few patients may have wheezes). Chest x-ray is indicated if there is any suspicion of pneumonia on history or physical exam.

- Follow-up not recommended unless:

• symptoms worsen or new symptoms develop (dyspnea, persistent fever, vomiting)
• coughing >1 month
• symptoms recur (>3 episodes/year).

Viruses

No antibiotic therapy recommended

Management

• increased humidity
• smoking cessation
• antitussives – may alleviate symptoms but will not reduce duration of illness
• bronchodilators – should not be used routinely but may have modest benefit for protracted cough, dyspnea, and wheezing.