303.3 🏥 內科專科考前版

303.3.1 Mechanistic Deep Dive

303.3.1.1 Pulmonary Function Test Pitfalls

  • Patient effort dependent
  • Reproducibility crucial (ATS criteria)
  • LLN (lower limit of normal) preferred over fixed cutoffs (esp elderly)
  • Race-specific predictions controversial
  • DLCO accuracy

303.3.1.2 Cryobiopsy vs Surgical Biopsy for ILD

  • Cryobiopsy advantages: less invasive, less mortality, comparable diagnostic yield
  • Surgical (VATS / wedge): largest sample, definitive
  • Cryobiopsy emerging as first-line for new ILD diagnosis

303.3.1.3 Robotic Bronchoscopy

  • Monarch (Auris/J&J): pull-wire technology
  • Ion (Intuitive): shape-sensing
  • Higher diagnostic yield for peripheral lesions
  • Tomosynthesis integration
  • 2024-2026 expanding use

303.3.2 Recent Trials & Updates

303.3.2.2 Liquid Biopsy in NSCLC

  • ctDNA for molecular profiling
  • Useful for resistance monitoring (T790M, C797S, MET amplification)
  • Less sensitive than tissue

303.3.2.3 AI in Chest Imaging (2024)

  • FDA-approved AI for CXR (nodule, pneumothorax detection)
  • HRCT pattern recognition for ILD
  • Reduces missed findings

303.3.2.4 Organoid Culture for Personalized Therapy

  • Patient-derived organoids from tumor / lung tissue
  • Drug screening
  • Personalized therapy selection
  • Emerging clinical use

303.3.2.5 IPF AI Diagnosis

  • Pattern recognition on HRCT
  • Reduces inter-observer variability
  • Multi-disciplinary discussion integration

303.3.3 High-Yield Specialist Points

303.3.3.1 BAL (Bronchoalveolar Lavage) Cell Differential

Normal: - Macrophages: 80-85% - Lymphocytes: 5-10% - Neutrophils: < 3% - Eosinophils: < 1%

Patterns: - Sarcoidosis: lymphocytic (CD4/CD8 > 4) - Hypersensitivity pneumonitis: lymphocytic (CD4/CD8 < 1) - Smoker / IPF: macrophages predominant - Eosinophilic pneumonia: eosinophils > 25% - Bacterial pneumonia: neutrophils - Alveolar hemorrhage: hemosiderin-laden macrophages - PAP (alveolar proteinosis): milky fluid + PAS+ material

303.3.3.2 Honeycombing Pattern

  • Definite UIP (Usual Interstitial Pneumonia) on HRCT
  • IPF diagnosis: clinical + HRCT honeycomb (no biopsy needed in some)
  • Sub-pleural + basal predominance

303.3.3.3 Pulmonary Vasculitis Workup

  • ANCA (c-ANCA = PR3 = GPA; p-ANCA = MPO = MPA / EGPA)
  • Anti-GBM (Goodpasture)
  • ANA, dsDNA (SLE)
  • Specific patterns

303.3.3.4 Massive Hemoptysis Bronchoscopy

  • Rigid bronchoscopy preferred
  • Cold saline lavage
  • Balloon tamponade
  • ICU clip placement
  • Bronchial artery embolization referral

303.3.3.5 Sleep Study Pearls

  • AHI ≥ 5 mild, ≥ 15 moderate, ≥ 30 severe
  • Central vs obstructive vs mixed
  • REM-dependent vs supine-dependent
  • ODI (oxygen desaturation index)
  • Arousal index

303.3.3.6 FeNO (Fractional Exhaled Nitric Oxide)

  • < 25 ppb: low Th2 inflammation
  • 25-50 ppb: intermediate

  • 50 ppb: high Th2 (asthma, eosinophilic)

  • Predicts ICS response

303.3.3.7 Pulmonary Function Test Equations

  • % Predicted: based on race, age, sex, height
  • Z-scores: standard deviation from mean (preferred recent ATS)
  • LLN (lower limit of normal): 5th percentile

303.3.3.8 Lung Cancer Screening (USPSTF 2021)

  • Age 50-80
  • ≥ 20 pack-year history
  • Current smoker OR quit < 15 years
  • LDCT annually

303.3.4 Pearls

  • HRCT is ILD gold standard
  • CTPA is PE gold standard
  • LUS revolutionized bedside (B-lines, sliding, BLUE protocol)
  • PFT patterns: obstructive (↓ FEV1/FVC) vs restrictive (↓ TLC) vs mixed
  • Light’s criteria: pleural exudate
  • Cryobiopsy + robotic bronchoscopy: 2024 standards
  • NSCLC molecular profiling: EGFR/ALK/ROS1/KRAS G12C/MET/BRAF/NTRK/PD-L1 — drives therapy
  • BAL cell patterns: sarcoid (lymphocytic CD4/CD8 > 4), HP (lymphocytic CD4/CD8 < 1), eosinophilic pneumonia (> 25% eosinophils)