361.2 🩺 國考版

361.2.1 高頻考點

361.2.1.1 Definition

  • Encephalopathy + INR ≥ 1.5 + no preexisting cirrhosis + < 26 weeks

361.2.1.2 Classification

  • Hyperacute (< 7 days) — best recovery
  • Acute (7-21)
  • Subacute (21-26 weeks) — worst

361.2.1.3 Etiology Distribution (US)

  • Acetaminophen (top, ~ 50%)
  • Idiosyncratic DILI
  • HBV
  • HAV
  • Autoimmune
  • Wilson
  • Budd-Chiari
  • Idiopathic

361.2.1.4 Worldwide Top

  • Viral (Asia, Africa)
  • HAV, HBV, HEV (pregnancy)

361.2.1.5 Key Workup

  • Acetaminophen level
  • Viral serologies (HAV IgM, HBsAg + anti-HBc IgM, HEV)
  • Autoimmune (ANA, anti-SMA, IgG)
  • Ceruloplasmin + slit lamp
  • Pregnancy
  • Doppler

361.2.1.6 King’s College Criteria — Acetaminophen

  • pH < 7.30 OR
  • All: INR > 6.5 + Cr > 3.4 + grade III/IV HE

361.2.1.7 King’s College Criteria — Non-Acetaminophen

  • INR > 6.5 OR
  • Any 3 of:
    • Age < 10 or > 40
    • Non-A non-B, drug
    • Jaundice → HE > 7 days
    • INR > 3.5
    • Bilirubin > 17.6 mg/dL

361.2.1.8 MELD ≥ 30

  • Also transplant indicator

361.2.1.9 NAC

  • For acetaminophen
  • Also for non-acetaminophen ALF (Lee 2009) — early HE (I-II)

361.2.1.10 Cerebral Edema

  • Hallmark of hyperacute ALF
  • Major cause of death
  • Mannitol, hypertonic saline
  • Head 30°

361.2.1.11 Pregnancy Causes

  • HELLP
  • AFLP
  • HEV (3rd trimester, 20% mortality)
  • Severe pre-eclampsia

361.2.1.12 Wilson ALF

  • Coombs-negative hemolytic anemia
  • Low alkaline phosphatase (paradoxical)
  • AST > ALT (often)
  • Almost always need transplant

361.2.1.13 Reye Syndrome

  • Children + aspirin + viral (flu, varicella)
  • Mitochondrial
  • Avoid aspirin in children

361.2.2 Specific Etiologies

361.2.2.1 Acetaminophen Toxicity

  • Toxic dose > 10 g acute
  • Chronic: > 4 g daily can be toxic with risk factors
  • Risk factors: alcohol, malnutrition, CYP inducers, hepatic disease
  • Markedly elevated AST/ALT (often > 1000s, > 10,000s)
  • Low bilirubin initially
  • INR ↑
  • NAC effective even late

361.2.2.2 HSV Hepatitis

  • Often without typical skin lesions
  • Pregnancy + immunocompromised
  • Anicteric hepatitis with marked transaminitis
  • Acyclovir IV
  • High mortality without treatment

361.2.2.3 Mushroom Poisoning

  • Amanita phalloides (death cap)
  • Initial GI symptoms 6-24 hr
  • Latent phase
  • Then hepatic failure
  • Silibinin + NAC + penicillin

361.2.2.4 Halothane Hepatitis

  • Historical (older anesthetic)
  • Repeated exposure
  • Severe ALF

361.2.3 Management Quick Reference

Issue Approach
HE I-II Lactulose, careful
HE III-IV Intubate, sedate, ICP
Cerebral edema Mannitol, hypertonic saline
Coagulopathy Don’t routinely correct
Hypoglycemia Frequent monitoring + dextrose
Renal CRRT
Sepsis Empiric Abx
Acetaminophen NAC
Severe ALF Transplant evaluation Status 1A