Bronchiectasis

Background

• Permanent dilatation of the small airways, causing persistent microbial infection

Etiologies

• Focal
  • Acquired
    • Chronic infection
      • Granulomatous
        • Tuberculosis
        • Histoplasmosis
        • MAC/NTM
      • Bacterial: Staphylococcus aureus, Klebsiella, Pseudomonas
      • Viral
    • Obstruction
      • Foreign body
      • Tumour
    • Right middle lobe syndrome
    • Swyer-James-MacLeod syndrome (postinfective obliterative bronchiolitis)
  • Congenital
    • Bronchopulmonary sequestration
    • Williams-Campbell syndrome (cartilage deficiency)
    • Mouner-Kuhn syndrome (tracheobronchmegaly)
• Diffuse
  • Genetic
    • Cystic fibrosis
    • Primary ciliary dyskinesia/Kartagener's syndrome
    • Alpha-1 antitrypsin deficiency
    • Young syndrome
  • Infectious: non-tuberculous mycobacterium/MAC
  • Immunodeficiency: hypogammaglobulinemia
  • Inflammatory: allergic bronchopulmonary aspergillosis
  • Autoimmune or immune-mediated
    • Rheumatoid arthritis
    • Sjögren syndrome
    • Inflammatory bowel disease
  • Bronchiolitis obliterans after transplant
  • Recurrent aspiration
  • Near drowning
  • Toxic inhalation
  • Miscellaneous
    • Yellow nail syndrome
    • Postradiation traction bronchiectasis
    • IPF

Clinical Manifestations

• Chronic cough (98%)
• Daily sputum (78%)
• Rhinosinusitis (73%)
• Dyspnea (62%)
• Hemoptysis (27%)
• Recurrent pleurisy (20%)

Investigations

• Labs
  • CBC, quantitative immunoglobulins, and HIV testing to rule out immunodeficiency
  • Sputum culture for bacteria, mycobacteria, and fungi; consider BAL
  • Sweat chloride testing +/- genetic testing to rule out CF
  • Alpha-1 antitrypsin levels (<11 in deficiency)
  • Nasal brush/biopsy to rule out ciliary dyskinesia
• Imaging
  • High-resolution CT
    • Signet-ring sign (airway >1.5x blood vessel) is best sign
    • Tram-tracking
• Other
  • PFTs
  • Bronchoscopy
  • Swallowing assessment to rule out aspiration

CT1

Cause	Distribution	Findings
Infection/Aspiration
Recurrent aspiration	lower lung zone, peripheral	bronchial wall thickening, aspirated material in bronchi, presence of hiatal hernia
ABPA	upper lung zone, central	high-attenuation mucous plugging
Tuberculosis	upper lung zone, focal or unilateral	asymmetric upper lobe involvement, tree-in-bud nodules
Non-tuberculous mycobacteria	middle lobe and lingular	more common in men with COPD or in thin, older women; indolent symptoms
Swyer-James syndrome	focal or unilateral	bronchial wall thickening, increased lucency in the small lung due to air trapping
Congenital
Cystic fibrosis	upper lung zone, central	extensive cystic and cylindrical bronchiectasis
Primary ciliary dyskinesia	middle lobe and lingular	situs inversus, chronic sinusitis, and bronchiectasis
Mounier-Kuhn syndrome	central	absence or atrophy of the elastic fibers and smooth muscle in trachea and main bronchial wall
Williams-Campbell syndrome	midorder bronch	cartilage deficiency in the midorder bronchi
Bronchial atresia	focal or unilateral	most common location
Fibrosing Diffuse Disease
Sarcoidosis	upper lung zone, central	bilateral hilar lymphadenopathy, perilymphatic nodules
Pulmonary fibrosis	lower lung zone, peripheral	varicoid bronchiectasis, architectural distortion, honeycombing in UIP
ARDS	middle lobe and lingular	varicoid bronchectasis, diffuse ground-glass opacities
Endobronchial/Peribronchial Lesions
Endobronchial tumour	focal or unilateral
Foreign body	focal or unilateral
Stricture	focal or unilateral
Other
Bronchiolitis obliterans	diffuse	significant cause of post-transplantation morbidity and mortality; diffuse air trapping

Management

Acute Exacerbation

• Send sputum cultures every time
• Cover empirically with usual pneumonia treatment x 14 days
• Add Pseudomonas or MRSA coverage if needed
• Consider prednisone if asthma or ABPA

Chronic Management

• Chest physiotherapy it most important
• Mucous (questionable utility outside of CF)
  • Hypertonic saline
  • Mannitol
  • DNAse/Pulmozyme is BAD outside of CF
  • Mucomyst
• Antiinflammatory
  • Consider inhaled bronchodilators if responsive
  • Consider azithromycin 500mg po MWF
• Inhaled antimicrobials, if colonozed with Pseudomonas and more than 3 exacerbations annually
  • Inhaled tobramycin
  • Inhaled colistin
  • Possibly inhaled ciprofloxacin
• Surgery: resection or transplantation can sometimes be considered
• Supportive
  • Annual flu vaccine
  • Smoking cessation
  • Pulmonary rehabilitation
  • GERD treatment

Further Reading

• British Thoracic Society Guideline for bronchiectasis in adults. Thorax. 2019;74:1-69. doi: 10.1136/thoraxjnl-2018-212463