397.3 🩺 內科專科考前版

397.3.0.1 📌 䞀頁重點

  • 22E updates:
    • Teprotumumab for Graves’ ophthalmopathy (IGF-1R blocker; FDA 2020) — game changer
    • TRAb 第䞉代 immunoassay 取代 TSI; 曎敏感 + 䟿宜
    • Pre-RAI prophylactic steroid for moderate eye disease (EUGOGO 指匕)
    • Amiodarone-induced thyrotoxicosis (AIT): Type 1 (high vascularity, color Doppler ↑) vs Type 2 (destructive); 鑑別 important for treatment
    • ICI thyroiditis: 60% biphasic, often permanent hypothyroid
    • Apathetic thyrotoxicosis in 老人 → AFib workup 必含 TFT
  • Taiwan: 健保 MMI/PTU/propranolol/RAI/thyroidectomy 充分; 健保 teprotumumab 自費 (very expensive); CTAOH/TES 指匕

397.3.0.2 🌟 Pearls (15)

397.3.0.2.1 Graves’
  1. Teprotumumab (Tepezza, IGF-1R Ab) for active moderate-severe Graves’ ophthalmopathy — proptosis ↓ ~3 mm; expensive
  2. EUGOGO classification: mild / moderate-severe / sight-threatening
  3. Smoking + Graves’ eye disease: 戒菞 RR ↓ 7-fold
  4. Selenium 200 ÎŒg/d for mild eye disease (controversial)
  5. High-dose IV methylprednisolone for active moderate-severe (4.5 g over 12 wk)
  6. Orbital decompression / strabismus / lid surgery sequential
  7. Total thyroidectomy + steroid prophylaxis option for severe eye + Graves’
397.3.0.2.2 ATD
  1. MMI 1st trimester teratogenic syndrome: aplasia cutis, choanal/esophageal atresia, dysmorphic facies
  2. PTU hepatotoxicity 0.1-0.2% (some fatal); not 1st line
  3. MMI agranulocytosis abrupt onset; CBC if sore throat / fever; do not use as routine screening
  4. MMI ANCA-associated vasculitis (rare)
  5. MMI/PTU cross-reactivity: ~50% for hepatotoxicity, < 50% for agranulocytosis (can switch with caution)
397.3.0.2.3 Special
  1. Amiodarone-induced thyrotoxicosis Type 1: thyroidectomy or RAI (after iodine washout); MMI ineffective alone
  2. Amiodarone-induced thyrotoxicosis Type 2: steroids; can continue amiodarone
  3. Plasmapheresis for refractory storm + drug allergy

397.3.0.3 📍 Taiwan + 健保

397.3.0.3.1 Drugs
  • 健保 MMI (methimazole, Carbimazole)
  • 健保 PTU (propylthiouracil)
  • 健保 propranolol
  • 健保 RAI (¹³¹I) for hyperthyroid + thyroid CA
  • 健保 thyroidectomy
397.3.0.3.2 Imaging + Workup
  • 健保 TFT, free T4/T3
  • 健保 anti-TPO, anti-Tg, TRAb (倧郚分院所)
  • 健保 RAIU + ¹²³I/⁹⁹ᵐTc scan
  • 健保 neck US
397.3.0.3.3 Eye Disease
  • Teprotumumab 自費 (NT$ 敞十萬-癟萬䞀療皋)
  • 健保 IV methylprednisolone for active disease
  • 健保 orbital RT, decompression surgery
  • 戒菞蜉介
397.3.0.3.4 孞會 + 指匕
  • CTAOH 台灣甲狀腺醫孞會 + TES 內分泌孞會
  • ATA 2016 hyperthyroidism guideline 對照
  • EUGOGO 2021 ophthalmopathy guideline

397.3.0.4 🎓 內專必懂 (15)

  1. Thyrotoxicosis vs hyperthyroidism + 鑑別暹
  2. RAIU 高 vs 䜎 病因鑑別
  3. Graves’ workup: TRAb + RAIU + ophthalmopathy assessment
  4. EUGOGO classification + management of Graves’ eye disease
  5. MMI vs PTU: 適應症 + 副䜜甚 + pregnancy 切換
  6. β-blocker symptomatic + D1 (high dose propranolol)
  7. RAI: dose, contraindication, pre-treatment, post-monitoring
  8. Thyroidectomy: pre-op euthyroid + Lugol + risks
  9. Thyroid storm: Burch-Wartofsky + treatment sequence + plasmapheresis salvage
  10. Pregnancy + lactation management (PTU 1st trimester, MMI later, TRAb 24-28 wk)
  11. Subclinical hyper: treat indications
  12. Apathetic thyrotoxicosis in 老人; AFib workup
  13. TPP (Asian male): K replacement + non-selective β-blocker
  14. Amiodarone Type 1 vs 2: distinction + treatment
  15. 22E: teprotumumab, AIT update, ICI thyroiditis, RAI ophthalmopathy prophylaxis

397.3.0.5 ⚙ Graves’ Ophthalmopathy Management (內專詳)

Activity assessment (CAS, Clinical Activity Score):
- Spontaneous orbital pain
- Pain on attempted gaze
- Eyelid redness
- Eyelid swelling
- Conjunctival redness
- Chemosis
- Inflammation of caruncle
+ in past 1-3 mo: ↑ proptosis, ↓ visual acuity, ↓ eye movement
- ≥ 3/7 = active

Severity assessment (EUGOGO):
- Mild: minimal symptoms
- Moderate-severe: significant impact (proptosis ≥ 3 mm, diplopia, lid retraction ≥ 2 mm, exposure)
- Sight-threatening: optic neuropathy, severe corneal ulcer

Treatment:
1. Smoking cessation (always)
2. Selenium 200 ÎŒg/d for mild
3. Active moderate-severe:
   - **IV methylprednisolone** (Marcocci): 0.5 g weekly × 6 wk, 0.25 g weekly × 6 wk (total 4.5 g)
   - **Teprotumumab** 8 IV doses q3 wk (better proptosis ↓; expensive)
   - **Orbital RT**: alternative (not pregnancy)
4. Sight-threatening: high-dose IV steroid + emergent decompression
5. Inactive (CAS < 3): rehab surgery (decompression → strabismus → lid)

Adjunct: artificial tears, prism glasses for diplopia, head elevation at sleep, sleep mask

397.3.0.6 ⚙ Amiodarone-Induced Thyrotoxicosis (AIT) Detailed

Feature Type 1 (Iodine-induced) Type 2 (Destructive)
Background gland Pre-existing nodular goiter Normal
Mechanism Excess I → ↑ synthesis Destructive thyroiditis
RAIU Variable / Normal-high Low
Color Doppler ↑ vascularity ↓ vascularity
IL-6 Normal ↑
Treatment MMI + sodium perchlorate; consider RAI/surgery Prednisone 40-60 mg/d × 6-8 wk
Amiodarone continuation Stop if possible Can continue (less critical)
Mixed Common; treat both with MMI + steroid

397.3.0.7 ⚙ Thyroid Storm 詳现處理 (內專)

1. ICU + ABCs + cardiac monitor
2. β-blocker:
   - Propranolol 60-80 mg PO q4h or 0.5-1 mg IV slow
   - Esmolol IV in cardiac compromise
   - Caveat: severe HF → use cautiously / not contraindicated absolutely
3. PTU 200-400 mg PO/NG q6h
4. Iodine 1 hr **after** PTU:
   - Lugol's solution 5-10 drops q6h
   - SSKI 5 drops q6h
   - **Lithium** alternative if iodine allergy
5. Hydrocortisone 100 mg IV q8h (also stress dose for AI possible)
6. Cooling: cooling blanket, acetaminophen (NOT aspirin — displaces from TBG → 加重)
7. Fluid + electrolyte
8. Treat trigger (infection, MI, etc)
9. Refractory: plasmapheresis (removes T4/T3 + antibody)
10. Mortality 10-30% even with optimal care

⚠ Iodine **before** PTU = substrate → 加重 (key pearl)

397.3.0.8 ⚙ Pregnancy Hyperthyroid Management (內專)

1st trimester:
- PTU (less teratogenic than MMI)
- Goal free T4 upper-normal range
- TSH may not normalize (and that's OK)
- Lowest effective dose

2nd-3rd trimester:
- Switch to MMI (PTU hepatotoxicity)
- Continue lowest effective dose

Mid-pregnancy:
- TRAb at 24-28 wk
  - High TRAb → fetal/neonatal Graves' surveillance
  - Fetal HR > 160, growth restriction, hydrops → fetal hyperthyroid
  
Delivery + postpartum:
- Switch back to MMI for breastfeeding
- Recheck TFT 6-12 wk post-partum
- 5-10% risk postpartum thyroiditis (different mechanism)

RAI: 絕對犁忌
Surgery: 2nd trimester preferred if needed
β-blocker: short-term use OK; avoid long-term (fetal growth restriction)

⚠ AI 草皿。