212.3 🩺 內科專科考前版

212.3.0.1 1⃣ HAV vs HEV Differential

Feature HAV HEV
Family Picornavirus Hepevirus
Transmission Fecal-oral Fecal-oral, pork/wild boar, blood
Geographic Worldwide S Asia + Mexico + some EU
Severity Usually mild; severe in older Mild in healthy; severe in pregnant (20-30% mortality 3rd trimester)
Chronic No Rare in immunocompromise (Genotype 3)
Vaccine Yes (HAVRIX, VAQTA) Hepai 239 (China only)
Diagnosis IgM anti-HAV IgM anti-HEV / PCR

212.3.0.2 2⃣ Cholestatic + Relapsing Forms

  • Cholestatic: prolonged jaundice + pruritus (months); UDCA for pruritus relief
  • Relapsing: recurrent over 6-12 mo; self-limited eventually; doesn’t progress to chronic

212.3.0.3 3⃣ HAV in Immunocompromise

  • Generally same outcome as healthy (acute, self-limited)
  • Severe in chronic liver disease coinfection
  • Reduced immunogenicity of vaccine (use 2-dose series + check titers)

212.3.0.4 4⃣ Twinrix (HAV + HBV)

  • Combination vaccine for travel + high-risk
  • 3-dose series (0, 1, 6 mo) or accelerated (0, 7, 21 d + booster 12 mo)
  • Efficient for travel medicine

212.3.0.5 5⃣ HAV in Pregnancy

  • Generally same outcome as non-pregnant
  • Severe / fulminant rare but possible (vs HEV pregnancy)
  • Vaccine safe in pregnancy if indicated
  • Vertical transmission rare

212.3.0.6 6⃣ Fulminant HAV Management

  • King’s College criteria: INR > 6.5 OR (Bilirubin > 17.5 mg/dL + age > 40 + INR > 3.5)
  • N-acetylcysteine — some benefit
  • Liver transplant referral

212.3.0.7 7⃣ 2017-2024 USA Outbreak Response

  • CDC vaccination campaigns
  • Outreach to homeless populations
  • Harm reduction (syringe services, supervised use)
  • Outbreak vaccination in shelters, drug treatment
  • Sanitation improvement
  • Surveillance

212.3.0.8 8⃣ 健保 / Taiwan

  • 公費 HAV vaccine high-risk (2018 expansion); some pediatric
  • 通報 mandatory
  • Taiwan endemic shifted (older birth cohorts immune; younger increasingly susceptible)
  • 盧醫垫 hint: 旅遊 / 慢性 肝病 + risk groups → recommend HAV vaccine

212.3.0.9 9⃣ Food Handler + Public Health

  • HAV-infected food handler must be removed from work
  • Restaurant patrons: vaccine + IG (within 14 days)
  • Outbreak investigation