What are the typical symptoms of acute bronchitis?

Acute Bronchitis Symptoms

Acute bronchitis presents predominantly with cough (with or without sputum production) lasting up to 3 weeks, often accompanied by upper respiratory symptoms like nasal congestion, sore throat, and sometimes constitutional symptoms including fever, muscle aches, and fatigue 1.

Primary Symptom

• Cough is the hallmark symptom - present in 92-93% of cases 1, 2
  • May be productive or non-productive
  • Typically lasts 2-3 weeks 3, 4
  • Can persist up to 3 weeks before alternative diagnoses must be considered 1

Associated Respiratory Symptoms

• Sputum production - occurs in approximately 63% of cases 2

  • May be mucoid or purulent
  • Important caveat: Purulent sputum does NOT indicate bacterial infection and does not justify antibiotic use 5
  • Purulence results from inflammatory cells or sloughed epithelial cells, occurring with both viral and bacterial infections

• Upper airway symptoms (often overlapping with common cold):

  • Nasal congestion/"runny nose" - 50-91% of cases 1, 2
  • Sore throat/throat pain - 50% of cases 2
  • Throat clearing and postnasal drip sensation 1
  • Sneezing 1

Constitutional Symptoms

When present, may include 1:

• Fever (though not always present)
• Muscle aches/myalgia
• Fatigue
• General malaise

Physical Examination Findings

Common findings include 2, 6:

• Pharyngeal erythema (45%)
• Wheezes (18%)
• Rhonchi (17%)
• Cervical lymphadenopathy (19%)

Critical Diagnostic Distinctions

The diagnosis should only be made after excluding 1:

1. Pneumonia - ruled out by absence of:

   • Heart rate ≥100 beats/min
   • Respiratory rate ≥24 breaths/min
   • Oral temperature >38°C
   • Focal consolidation on chest exam (rales, egophony, fremitus) 1, 5

2. Common cold - difficult to distinguish clinically as symptoms overlap significantly 1

3. Acute asthma - approximately one-third of patients presenting with acute cough are misdiagnosed 1

   • Consider if cough persists >3 weeks or patient has had ≥2 similar episodes in past 5 years (65% have mild asthma) 1

4. COPD exacerbation - in patients with known chronic bronchitis 1

Important Clinical Pitfalls

• Transient bronchial hyperresponsiveness occurs in ~40% of previously healthy individuals with acute viral respiratory infections 1
• Purulent sputum appearance is NOT diagnostic of bacterial infection and should not trigger antibiotic prescription 5
• The clinical distinction between acute bronchitis and common cold is often "difficult, or at times impossible, to make" 1
• Symptoms overlapping with influenza include weakness (94%), myalgia (94%), cough (93%), and nasal congestion (91%) 1