306.4 📋 章末速記 Summary

306.4.1 🔑 一句話總結

HP (hypersensitivity pneumonitis) = 過敏性肺炎，inhaled antigen 誘發 immune-mediated ILD；分 fibrotic (chronic) vs non-fibrotic (2020 ATS update)；HRCT mosaic attenuation + centrilobular nodules + 上中肺野；BAL lymphocytosis with CD4/CD8 < 1（vs sarcoid > 4）；治療：antigen avoidance is most important + steroids + nintedanib/pirfenidone for fibrotic HP (INBUILD)；Eosinophilic pulmonary diseases：acute (AEP, smoking trigger, BAL eos > 25%, dramatic steroid response)；chronic (CEP, asthma association, “photographic negative of pulmonary edema”, relapse 50%)；ABPA (asthma/CF + IgE > 1000 + central bronchiectasis, itraconazole + steroids + dupilumab refractory)；EGPA (asthma + eosinophilia + vasculitis, mepolizumab Class I)；HES (> 1500 eos, FIP1L1-PDGFRA → imatinib)。

306.4.2 💊 治療精要

• HP non-fibrotic：antigen avoidance + prednisone 0.5-1 mg/kg/d × 2-4 wk → taper
• HP fibrotic：nintedanib (INBUILD)、pirfenidone、azathioprine/MMF、transplant for end-stage
• AEP：steroids dramatic（prednisone 40-60 mg/d × 2-4 wk）；smoking cessation
• CEP：steroids long-term；relapse 50%；steroid-sparing dupilumab/mepolizumab/benralizumab emerging
• ABPA：oral prednisone 0.5 mg/kg + itraconazole 200 mg BID × 4-6 mo；dupilumab for refractory
• EGPA：steroids + cyclophosphamide (severe) / rituximab (ANCA+) / mepolizumab Class I
• HES：imatinib (FIP1L1-PDGFRA+)；steroids；mepolizumab；ruxolitinib

306.4.3 🎯 盧醫師的考前提醒

1. HP 抗原與職業關聯經典：farmer’s lung (thermophilic actinomycetes)、bird fancier’s (avian)、hot tub lung (MAC)、isocyanate HP、cheese washer’s (penicillium)、bagassosis (sugar cane)、suberosis (cork)
2. HP vs sarcoidosis BAL：HP CD4/CD8 < 1、sarcoid CD4/CD8 > 4（key distinguisher）
3. HP HRCT：non-fibrotic = mosaic attenuation + centrilobular nodules + ground-glass；fibrotic = 上中肺野 reticulation + traction bronchiectasis + honeycombing (vs IPF basilar)
4. INBUILD 2019 + 2020 ATS guidelines：nintedanib for progressive fibrotic HP (FVC decline 減緩) — game-changer
5. antigen avoidance is most important intervention in HP — 即使 steroids 也救不回 fibrosis
6. AEP 特徵三聯：acute 表現（days）+ smoking new initiation + BAL eos > 25%（peripheral eos 常 absent at presentation）+ dramatic steroid response within days
7. CEP “photographic negative of pulmonary edema” HRCT pattern：peripheral + upper lobe predominant；relapse 50%
8. ABPA 5 stages (Rosenberg-Patterson)：acute → remission → exacerbation → corticosteroid-dependent → end-stage fibrosis；dupilumab emerging for refractory
9. EGPA + mepolizumab Class I（2017 FDA approved）— 唯一 vasculitis-associated 有 biologic approval
10. HES + FIP1L1-PDGFRA mutation → imatinib responsive（myeloid subtype）；mepolizumab approved for HES；lymphocytic (T-cell driven) variant 治療不同