Hepatitis E 

India → mostly Genotype 1

Modes of Transmission

1️⃣ Feco-Oral (Most common in India)

  • Contaminated water
  • Flood-related outbreaks
  • Poor sanitation

2️⃣ Zoonotic (Genotype 3/4)

  • Undercooked pork
  • Deer meat

3️⃣ Blood Transfusion

Rare but documented.

4️⃣ Vertical Transmission

  • Mother → fetus
  • High neonatal mortality


 Pathogenesis

  • Virus enters via GI tract
  • Replicates in intestine → liver
  • Hepatocyte infection
  • Immune-mediated injury (CD8 T cell mediated)

Severity depends on:

  • Host immune response
  • Pregnancy status
  • Pre-existing liver disease


 Why Is HEV So Severe in Pregnancy?

Mortality in 3rd trimester: 20–30%

Mechanisms:

  • Hormonal changes (estrogen/progesterone immune modulation)
  • Th2 immune shift
  • High viral replication
  • Altered cytokine response
  • Increased viral load

➡ Leads to:

  • Fulminant hepatic failure
  • DIC
  • Encephalopathy
  • Maternal death


 Clinical Features

1️⃣ Incubation Period

2–8 weeks (average 5–6 weeks)


2️⃣ Acute Hepatitis

Prodromal Phase

  • Fever
  • Malaise
  • Anorexia
  • Nausea
  • Vomiting

Icteric Phase

  • Jaundice
  • Dark urine
  • Pale stools
  • Hepatomegaly
  • Mild RUQ pain

Usually self-limiting (2–6 weeks)


3️⃣ Fulminant Hepatic Failure (FHF)

Especially:

  • Pregnant women
  • Pre-existing liver disease

Features:

  • Rapid INR rise
  • Encephalopathy
  • Cerebral edema
  • Renal failure
  • DIC


4️⃣ Acute-on-Chronic Liver Failure (ACLF)

In cirrhotics:

  • HEV superinfection
  • Massive decompensation
  • Ascites
  • AKI
  • Sepsis-like picture

Common in India.


5️⃣ Chronic Hepatitis E

Occurs mainly in:

  • Transplant recipients
  • HIV
  • Chemotherapy
  • Immunosuppressed

Usually Genotype 3.

Defined as:

  • HEV RNA > 3 months

Can lead to:

  • Rapid fibrosis
  • Cirrhosis


 Laboratory Diagnosis

 LFT Pattern

  • ALT > AST
  • Marked transaminase elevation (1000–3000 IU)
  • Bilirubin elevated
  • INR may rise in severe disease


 Serology

Test

Interpretation

Anti-HEV IgM

Acute infection

Anti-HEV IgG

Past exposure

HEV RNA (PCR)

Active infection

PCR required for:

  • Immunocompromised
  • Chronic infection
  • Transplant patients


 Imaging

USG Findings:

  • Hepatomegaly
  • Increased echogenicity
  • Usually nonspecific

Imaging mainly to:

  • Exclude obstruction
  • Rule out Budd-Chiari
  • Assess complications


 Management (According to Current Guidelines)

1️⃣ Acute Uncomplicated HEV

✔ Supportive care

  • Hydration
  • Antiemetics
  • Avoid hepatotoxic drugs

No specific antiviral in routine cases.


2️⃣ Fulminant Hepatic Failure

Manage as per acute liver failure protocol:

  • ICU admission
  • Lactulose
  • Ammonia control
  • ICP monitoring
  • Early transplant referral

In India:
HEV is a leading cause of liver transplant referral in pregnancy.


3️⃣ Chronic HEV

Treatment:

  • Reduce immunosuppression
  • Ribavirin for 12 weeks

Ribavirin contraindicated in pregnancy.


4️⃣ Pregnancy

No proven antiviral safe.

Management:

  • Early ICU monitoring
  • Early transplant evaluation
  • Aggressive coagulopathy correction


 Vaccine

China has licensed HEV vaccine (HEV 239).

Not globally available.

India:
No routine vaccination.


 Complications

  • Fulminant hepatic failure
  • Cerebral edema
  • DIC
  • Acute kidney injury
  • Pancreatitis
  • Guillain-Barré syndrome
  • Neuralgic amyotrophy

Neurological associations increasingly reported.