121.2 📚 國考版醫垫國考 / PGY OSCE

121.2.0.1 📌 Cram Sheet

121.2.0.1.1 🔥 高 yield 12
  1. Joint / muscle / 深郚 bleed = factormucocutaneous = platelet/vessel/vWD
  2. PT 反映 VII (+ common: X, V, II, I)PTT 反映 VIII/IX/XI/XII (+ common)
  3. Hemophilia A (FVIII) 1/5,000 男B (FIX) 1/30,000 男X-linked recessive
  4. Hemophilia 22EEmicizumab SC weekly (HAVEN, even 對 inhibitor) + Gene therapy (Roctavian for A 2023, Hemgenix for B 2022)
  5. Inhibitor (5-30% A): bypass with FEIBA / rFVIIaITI 根陀
  6. vWD 最垞芋 inherited bleed disorder (1% population)Type 1 75%Type 2B 犁 DDAVPType 3 嚎重 → vWF concentrate
  7. vWF tests: vWF Ag, Ristocetin cofactor (RiCof), FVIII level, multimer analysis
  8. DIC: thrombin + fibrinolysis 同時 → bleed + thrombosisplt ↓, PT/PTT ↑, fibrinogen ↓, D-dimer ↑↑, schistocytes
  9. APL (M3) DIC: ATRA + anthracycline 立即 → 24-72 h DIC 改善
  10. Vit K dependent factors: II, VII, IX, X + protein C, SVII 半衰期最短 → PT 最早 prolonged
  11. Acquired hemophilia: 老/劊嚠/autoimmune + Anti-FVIII Ab → PTT 䞍 correct on mixing → bypass agent + rituximab + immunosuppression
  12. FXIII deficiency: delayed bleed (24-72 h) + 臍垶出血 + ICHPT/PTT normal
121.2.0.1.2 🔢 必背敞字
項目 æ•žå­—
Hemophilia A incidence 1 in 5,000 男
Hemophilia B incidence 1 in 30,000 男
Severe hemophilia FVIII / IX < 1%
Moderate 1-5%
Mild 5-40%
Inhibitor frequency hemo A 5-30%
vWD population prevalence ~ 1%
vWD type 1 % ~ 75%
FVII half-life 6 hr (shortest)
Cryo fibrinogen 補充 indication < 100 active bleed

121.2.0.2 ⭐ 高 yield è¡š

121.2.0.2.1 Coag Test 解讀
PT PTT TT 想
↑ normal normal VII def, warfarin early, mild liver
normal ↑ normal VIII (hemo A), IX (hemo B), XI, vWD 2N/3, lupus AC, heparin
↑ ↑ normal Common (X/V/II/I), warfarin late, severe vit K def, liver, DIC, dilution
↑ ↑ ↑ Fibrinogen def, dysfibrinogenemia, heparin (PTT only), DIC
121.2.0.2.2 Hemophilia A vs B vs vWD
Hemo A Hemo B vWD
Defect FVIII FIX vWF
Inheritance X-linked R X-linked R AD (mostly)
Frequency 1/5,000 男 1/30,000 男 1% pop
Bleed type Joint, muscle, ICH Joint, muscle, ICH Mucocutaneous, menorrhagia
PTT ↑ ↑ ↑ (if FVIII ↓)
FVIII ↓↓ normal ↓ (carrier effect)
FIX normal ↓↓ normal
vWF normal normal ↓↓ (type 1/3)
Treatment rFVIII / emicizumab / Roctavian rFIX / Hemgenix DDAVP (type 1) / vWF concentrate
121.2.0.2.3 vWD 分型
Type 機制 DDAVP
1 (75%) Quant ↓ Yes
2A ↓ HMW multimers Yes 郚分
2B ↑ binding → 甹 platelet NO (加重 thrombocytopenia)
2M ↓ binding Yes 郚分
2N ↓ FVIII binding Yes 郚分
3 (severe) 完党猺 NO (䞍效)
121.2.0.2.4 Hemophilia 22E 治療
治療 機制 適應
Emicizumab (Hemlibra) Bispecific Ab mimic FVIII Hemo A ± inhibitor; SC weekly/biweekly/monthly
Roctavian (valoctocogene roxaparvovec) AAV-FVIII gene therapy Severe hemo A, single IV
Hemgenix (etranacogene dezaparvovec) AAV-FIX gene therapy Hemo B, single IV
Concizumab (Alhemo) Anti-TFPI Hemo A or B with inhibitor
Marstacimab (Hympavzi) Anti-TFPI Hemo A/B 22E approved 2024
Fitusiran Anti-AT3 RNAi Phase 3
121.2.0.2.5 DIC vs Liver Disease vs Vit K Def
DIC Liver disease Vit K def
PT ↑ ↑ ↑↑ (most early)
PTT ↑ ↑ (later) ↑ later
Plt ↓ ↓ (hyper­splenism) normal
Fibrinogen ↓↓ ↓ later normal
D-dimer ↑↑↑ mild ↑ normal
FVIII normal/↑ normal/↑ (key!) normal
Treatment underlying + supportive Vit K + factor support Vit K + 4F-PCC

→ Liver disease 鑑別 DIC 的 key: FVIII normal/↑ in liver (FVIII 埞 endothelium䞍䟝賎 hepatic synthesis)DIC äž­ FVIII ↓

121.2.0.3 🎯 自我檢枬 12 題

  1. PTT prolonged + normal PT + æ ¡æ­£ mixing → 鑑別 → Factor deficiency (VIII, IX, XI, XII)
  2. PTT prolonged + 䞍校正 → 鑑別 → Inhibitor (lupus AC, factor inhibitor, heparin)
  3. Hemophilia A 猺什麌 → FVIII
  4. Hemophilia 22E SC ab? → Emicizumab (Hemlibra)
  5. Hemo A gene therapy 22E? → Roctavian
  6. Hemo B gene therapy 22E? → Hemgenix
  7. vWD 最垞芋 type? → Type 1 (75%)
  8. vWD 哪 type 犁 DDAVP? → Type 2B + Type 3
  9. vWD è©Šé©— 䞉倧? → vWF Ag + RiCof + FVIII level
  10. DIC 暙誌 lab? → ↓ fibrinogen + ↑↑ D-dimer + ↑ PT/PTT + ↓ plt
  11. APL DIC 治療? → ATRA + anthracycline (立即)
  12. FXIII deficiency 特埵? → Delayed bleed + 臍垶出血 + PT/PTT normal

121.2.0.4 🩺 PGY OSCE 堎景

121.2.0.4.1 Scenario 13 歲男孩 hemarthrosis + 家族史 → diagnose hemophilia A
  • PTT prolonged + correct on mixing
  • FVIII < 1% → severe
  • Treatment: rFVIII prophylactic 25-40 IU/kg 3x/wk; 或 emicizumab SC q1-4 wk
  • Bleed: rFVIII 50 IU/kg + ICE 衛教
  • 避 IM, NSAID, contact sport
  • Family: female 芪屬 carrier testing
121.2.0.4.2 Scenario 2DIC 治療
  • 確認 underlying cause (sepsis, malignancy, OB)
  • Treat underlying aggressively
  • Supportive: cryo if fib < 100 + bleed; FFP if INR > 1.5 + bleed; plt if < 50 + bleed
  • 䞍 routine heparin (陀非 dominant thrombosis)
121.2.0.4.3 Scenario 3APL 新蚺斷 + DIC
  • ATRA 啟動 within hours of diagnosis
    • idarubicin or arsenic
  • Daily fib + plt + PT + DD monitor
  • Cryo, FFP, plt support during 24-72 hr remediation
  • 監枬 differentiation syndrome (steroid)

⚠ AI 草皿。