Epidemiology

  • 50% acquired during travels abroad

Etiology

  • Contaminated water and food (e.g., raw shellfish)

Pathophysiology

  • HAV is not cytopathic in itself; research suggests that liver damage is caused by cellular immunity (especially CD8+ T cells).

Clinical features

Tip

Unlike hepatitis B or C, HAV infection is a self-limiting disease that is not associated with an asymptomatic viral carrier state and does not progress to chronic hepatitis, cirrhosis, or hepatocellular carcinoma.

In children age < 6, HAV infection is most often (>80%) silent or subclinical . Clinical disease is typically more severe (70% of symptomatic patients with jaundice) in adults (some of whom develop an aversion to smoking, for unclear reasons)

  • Incubation period: 2–6 weeks
  • Phases of acute viral hepatitis
    • Prodromal phase: 1–2 weeks
      • Right upper quadrant pain, tender hepatomegaly
      • Fever, malaise
      • Anorexia, nausea, vomiting
    • Icteric phase: ∼ 2 weeks
    • Resolution of symptoms

Diagnostics

  • Liver biopsy: not routinely indicated
    • Periportal inflammation (mononuclear cell infiltration)
    • Hepatocyte swelling
    • Ballooning degeneration
    • Bridging necrosis
    • Councilman bodies (apoptotic hepatocytes)

Treatment