308.2 🩺 國考版

308.2.1 高頻考點

308.2.1.1 Etiology

  • Post-infectious (30%): childhood pneumonia, TB, NTM, pertussis
  • Immunodeficiency (10%): CVID, IgG deficiency
  • ABPA
  • Connective tissue (RA most common)
  • IBD
  • Genetic: CF, PCD/Kartagener, Young’s, α1-AT
  • Aspiration
  • Idiopathic (up to 50%)

308.2.1.2 HRCT Signs

  • Tram tracks (parallel airways)
  • Signet ring (bronchus larger than artery)
  • Mucus plugging (finger-in-glove)
  • Cluster of cysts
  • Patterns: cylindrical, varicose, cystic

308.2.1.3 Microbiology

  • H. influenzae (30%)
  • Pseudomonas (30%) — predicts worse outcomes
  • S. aureus
  • NTM (MAC most common)
  • ABPA / Aspergillus (some)

308.2.1.4 Treatment Pillars

  • Airway clearance (chest PT, OPEP, hypertonic saline)
  • Antibiotics (acute + chronic suppressive)
  • Treat underlying
  • Brensocatib (2024) — disease-modifying
  • Inhaled antibiotics for Pseudomonas

308.2.1.5 Key Trials

  • EMBRACE, BAT, BLESS: azithromycin chronic ↓ exacerbations
  • ASPEN (2024): brensocatib (DPP-1 inhibitor) positive

308.2.1.6 Special Populations

  • Kartagener: PCD + situs inversus + sinusitis
  • Lady Windermere syndrome: elderly women + MAC + right middle lobe / lingula bronchiectasis
  • DPB: Asian, erythromycin dramatic response

308.2.1.7 NTM Diagnosis (ATS/IDSA)

  • Clinical + radiographic + 2 positive sputum cultures OR 1 BAL
  • Treatment: macrolide + ethambutol + rifampin × 12 months after culture conversion

308.2.2 易混淆比范

Feature Bronchiectasis COPD Asthma
Sputum Large volume, purulent Variable Variable
Cough Productive chronic Productive in chronic bronchitis Variable
HRCT Bronchial dilation Emphysema Usually normal
Etiology Post-infectious, genetic, autoimmune Smoking, AAT Allergic, genetic
Treatment Airway clearance + antibiotics LABA-LAMA + ICS ICS-formoterol

308.2.3 Special Topics

308.2.3.1 Causes of Hemoptysis in Bronchiectasis

  • Inflammation + erosion
  • Bacterial superinfection
  • ABPA exacerbation
  • Lung cancer (separate workup)
  • TB / NTM
  • Massive: bronchial artery embolization

308.2.3.2 Brensocatib Mechanism

  • DPP-1 (dipeptidyl peptidase 1) inhibitor
  • Inhibits activation of neutrophil serine proteases (elastase, cathepsin G, proteinase 3)
  • Reduces airway inflammation
  • ASPEN 2024 positive Phase 3