Does bronchiolitis produce a cough with significant expectoration?

Bronchiolitis and Cough with Expectoration

Bronchiolitis typically produces cough but with minimal expectoration, as it primarily affects small airways (bronchioles) rather than larger airways where mucus production is more significant. 1

Pathophysiology of Cough in Bronchiolitis

Bronchiolitis is characterized by inflammation, fibrosis, and architectural distortion of the small airways (< 2mm in diameter). The pathogenesis of cough in bronchiolitis involves:

• Inflammation of small airways 1
• Airway wall thickening 1
• Potential mucous hypersecretion, though typically less prominent than in bronchitis 1
• Bronchial hyperresponsiveness in some cases 1

Clinical Presentation and Expectoration Patterns

Acute Viral Bronchiolitis

• Primarily affects children under 2 years 1
• Typically presents with tachypnea, wheeze, and/or crackles following an upper respiratory illness 1
• Cough is common but usually not productive of significant sputum 2
• Mean time of cough resolution is 8-15 days, with 90% of children cough-free by day 21 1

Chronic Bronchiolitis

• In adults with chronic bronchiolitis, cough may be present but the amount of expectoration varies:
  • Non-suppurative forms (e.g., cryptogenic bronchiolitis obliterans) typically produce dry cough 1
  • Suppurative forms may produce some sputum but less than bronchiectasis 1
  • Diffuse panbronchiolitis (DPB) is an exception that can produce copious purulent sputum 1

Diagnostic Considerations

When evaluating patients with suspected bronchiolitis and cough:

1. Consider bronchiolitis in patients with:

   • Cough and incompletely reversible airflow limitation 1
   • Clinical syndrome suggestive of infection 1
   • Direct or indirect signs of small airways disease on HRCT 1

2. Diagnostic workup should include:

   • Comprehensive medical history and physical examination 1
   • Pulmonary function tests (spirometry with bronchodilator response) 1
   • High-resolution CT scan with expiratory cuts 1
   • Bronchoscopy may be needed to rule out infection or evaluate for purulent secretions 1

3. Key radiographic findings:

   • Direct signs: small nodules, tree-in-bud pattern 1
   • Indirect signs: mosaic attenuation on expiratory scanning 1
   • CXR may be normal despite significant disease 1

Special Types of Bronchiolitis with Expectoration

Diffuse Panbronchiolitis (DPB)

• Primarily found in Japan, Korea, and China 1
• Characterized by chronic sinusitis, cough with copious purulent sputum, wheezing, and dyspnea 1
• Responds well to macrolide antibiotics 1

Infectious Bacterial Bronchiolitis

• Can produce purulent secretions visible on bronchoscopy 1
• Requires prolonged antibiotic therapy 1

Post-Infectious Bronchiolitis

• May persist for 3-8 weeks after acute respiratory infection 1
• Typically produces less expectoration than bacterial causes 1

Management Implications

The presence or absence of significant expectoration helps guide management:

1. For suppurative forms with purulent secretions:

   • Prolonged antibiotic therapy is recommended 1
   • For DPB, macrolide antibiotics (erythromycin, clarithromycin, or roxithromycin) for ≥2-6 months 1

2. For non-suppurative forms:

   • Treatment depends on underlying cause 1
   • Corticosteroids may be beneficial in some forms (e.g., IBD-related bronchiolitis) 1

3. For acute viral bronchiolitis in children:

   • Supportive care is the mainstay of treatment 3, 2
   • Antibiotics should be avoided unless specific evidence of bacterial co-infection 3, 2
   • Bronchodilators, corticosteroids, and chest physiotherapy are not routinely recommended 2

Common Pitfalls and Caveats

• Do not confuse bronchiolitis with bronchitis or bronchiectasis, which typically produce more significant expectoration 1
• Normal chest X-ray does not exclude bronchiolitis due to the small airway involvement 1
• Bacterial suppurative airways disease may be clinically unsuspected and requires bronchoscopy for diagnosis 1
• In patients with chronic cough after bronchiolitis, avoid unnecessary use of asthma medications unless clear evidence of asthma is present 1

In summary, while bronchiolitis does cause cough, it typically produces minimal expectoration except in specific variants like diffuse panbronchiolitis or infectious bacterial bronchiolitis.