Hepatitis A and Hepatitis E - Management

HEPATITIS A (HAV)

The Pathogen & Epidemiology

• Travelers to developing countries
• Men who have sex with men
• Injection drug users
• Homeless persons
• Children in day-care centers (and their parents)
• Patients receiving clotting factor concentrates (hemophilia)
• Persons in institutional settings

Clinical Features

• Often mild and anicteric, especially in children
• Symptomatic icteric disease becomes more common with older age at infection
• Prodrome: fatigue, anorexia, nausea, right upper quadrant discomfort, fever
• Icteric phase: jaundice, dark urine, pale stools, pruritus
• Elevated ALT/AST (peaks early in acute phase), conjugated hyperbilirubinemia
• In 5-10% of cases, a secondary enzyme rise ("relapse") occurs
• Self-limited in nearly all cases - never progresses to chronic hepatitis
• Rare complication: fulminant hepatic failure (acute liver failure - ALF)
• Prolonged cholestatic course can occasionally occur

Serologic Course

Serologic course of acute hepatitis A. ALT peaks early; Anti-HAV IgM is the diagnostic marker of acute infection; Anti-HAV IgG persists lifelong. - Goldman-Cecil Medicine

Diagnosis

• Anti-HAV IgM by enzyme immunoassay is the standard diagnostic test
• HAV RNA (PCR) can be detected in stool/body fluids but is not routinely required
• "Total anti-HAV" assays (IgM + IgG combined) indicate exposure/immunity but cannot distinguish acute from past infection
• Serology should only be ordered in symptomatic individuals to avoid false positives

Treatment

• Prothrombin time prolongation and bilirubin/lactate levels are the key prognostic markers
• Serum aminotransferase levels and viral load do NOT carry prognostic value
• Prognosis is generally excellent; death is exceedingly rare, confined to fulminant cases

Prevention

• Inactivated virus vaccine (purified from cell culture)
• Standard schedule: 2 doses, 6-18 months apart
• Accelerated schedule: Days 0, 7, and 21 (for last-minute travelers to endemic areas)
• Seroconversion: virtually 100% in healthy individuals; lower in immunocompromised
• Protective antibodies persist for at least 27 years after childhood/young adult vaccination
• A combination HAV + HBV vaccine is available
• Part of routine childhood immunization in many countries

• Non-immune travelers to endemic countries
• Healthcare workers
• MSM
• Close contacts of HAV cases
• Patients with chronic liver disease (CLD)

• ~98% effective for post-exposure prophylaxis
• Used together with HAV vaccine in the post-exposure setting
• HAV vaccine preferred as it also prevents secondary cases

HEPATITIS E (HEV)

The Pathogen & Epidemiology

• ~20 million infections and 3.3 million symptomatic cases per year worldwide
• ~44,000 deaths per year (2015 estimate)
• Over 60% of cases and deaths in East and South Asia

1. Fecal-oral (contaminated water) - primary route for GT1/2
2. Zoonotic/foodborne (undercooked pork, boar, deer meat) - GT3/4
3. Blood transfusion
4. Vertical (mother to fetus)

Clinical Features

• Resembles acute hepatitis A clinically
• Prodrome: flu-like symptoms, fever, chills, abdominal pain, anorexia, nausea, vomiting, arthralgia, transient rash
• Icteric phase (1-7 days later): jaundice, dark urine, clay-colored stools, pruritus (lasting weeks)
• Labs: elevated ALT, AST, GGTP, conjugated hyperbilirubinemia, mild leukopenia, relative lymphocytosis
• Case-fatality rate: 0.5-4% in hospital-based data; 0.07-0.6% in population surveys
• Usually self-limited; may have a prolonged cholestatic variant with spontaneous resolution

• Neurological: Guillain-Barre syndrome, neuralgic amyotrophy, encephalitis
• Renal, hematologic, autoimmune manifestations
• Acute pancreatitis

Diagnosis

• In endemic areas: IgM anti-HEV is sufficient for clinical diagnosis
• In non-endemic areas (low pre-test probability): HEV RNA confirmation recommended
• Immunodeficient patients may lack antibody response - HEV RNA is essential

Treatment

Acute Hepatitis E

Chronic Hepatitis E (mainly in immunosuppressed GT3/4)

1. Step 1 - Reduce immunosuppression: Reduction or withdrawal of immunosuppressive drugs leads to spontaneous clearance of HEV in approximately one-third of transplant patients
2. Step 2 - Ribavirin: If immunosuppression cannot be adequately reduced, or if reduction fails:
   • Ribavirin ~600 mg/day for 3 months
   • High rates of sustained virologic response (SVR) - defined as undetectable HEV RNA 3-6 months after treatment cessation
   • No controlled RCTs available; evidence from retrospective case series
   • Some patients show HEV genome mutations conferring ribavirin resistance at treatment failure
3. Step 3 - Pegylated interferon-alpha (PEG-IFN-α): Used in select patients (e.g., those who fail ribavirin or in liver transplant recipients when ribavirin is not appropriate); evidence is limited to case reports/series

A 2025 review (PMID: 40693961) highlights the management of HEV in organ transplant recipients as an evolving area, reinforcing the ribavirin-first approach for chronic HEV post-transplant.

Prevention of Hepatitis E

Key Comparison: HAV vs. HEV