Virology And Epidemiology

Organism Characteristics

• Single-stranded RNA virus; Picornavirus family; heat stable.
• Represents most common cause of acute viral hepatitis globally; accounts for 40-60% of pediatric cases in endemic regions.

Transmission Dynamics

• Strict feco-oral transmission via person-to-person contact, contaminated food, or contaminated water.
• Incubation period ranges 15-50 days (mean 3-4 weeks).
• Highly contagious; peak fecal viral shedding occurs prior to symptom onset and ceases approximately 2 weeks post-jaundice onset.
• Maternal-neonatal transmission absent; chronic infection state does not occur.

Clinical Manifestations

Symptomatology By Age

• Young Children (<6 years): Frequently asymptomatic or anicteric; clinically indistinguishable from nonspecific viral gastroenteritis.
• Older Children/Adolescents: Symptomatic acute febrile illness featuring abrupt onset.

Disease Phases

Complications And Atypical Presentations

• Acute Liver Failure (ALF): Rare (<1% in developed nations, higher in endemic zones); features worsening encephalopathy (irritability, altered sleep), persistent anorexia, and uncorrectable coagulopathy.
• Prolonged Cholestatic Syndrome: Waxes and wanes over several months; marked by severe pruritus and fat malabsorption without hepatic synthetic dysfunction.
• Extrahepatic Complications:
  • Hematologic: Bone marrow hypoplasia, aplastic anemia, autoimmune hemolytic anemia.
  • Gastrointestinal: Acute pancreatitis, acalculous cholecystitis, intestinal ulceration.
  • Systemic: Leukocytoclastic vasculitis, cryoglobulinemia, nephritis, reactive arthritis, myocarditis.

Diagnostic Evaluation

Laboratory Findings

• Significant elevation of Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST).
• Conjugated hyperbilirubinemia; bilirubin peaks later and normalizes slower than transaminases.
• Normal albumin and prothrombin time/INR (unless ALF develops).
• Mild leukopenia featuring relative lymphocytosis.

Serological Markers

Imaging

• Abdominal Ultrasonography: Mild hepatomegaly, increased hepatic echogenicity, marked edema of gallbladder wall, periportal lymphadenopathy.

Management Protocol

Medical Therapy

• Strict supportive care; specific antiviral pharmacotherapy unavailable.
• Maintain hydration; intravenous crystalloid fluids indicated for intractable vomiting or clinical dehydration.
• Prolonged Cholestasis: Administer antipruritic agents and fat-soluble vitamins (A, D, E, K).
• Avoid hepatotoxic medications; enforced strict bed rest unnecessary.
• Monitor serially for ALF (encephalopathy, worsening coagulopathy); refer immediately to transplant center if ALF suspected.

Prevention And Prophylaxis

• Mandate strict sanitation, safe drinking water, and rigorous handwashing hygiene.
• Exclude infected children from school/childcare for 1 week post-jaundice onset.