Viral hepatitis

Question 1

Hepatits A

• Virus type
• Scope
• Spread
• Symptoms & signs
• Tests
• Management
• CLD?
• Prevention

Answer 1

• Virus type;
  
  • RNA Picornavirus
• Scope
  
  • Self-limiting <6wks
• Spread;
  
  • F/O
• Symptoms;
  
  • ​Incubation 4wks
  • Prodrome of flu; fever, malaise, anorexia, nausea, arthralgia
    
    • Dislike of cigarettes!
  • Jaundice +/- hepatomegaly, splenomegaly, adenopathy
    
    • Icteric phase; dark urine, pale stools, abdo pain etc
• Tests;
  
  • ↑ALT >↑AST & ↑bilirubin after incubation - return to normal
  • IgM antibody after incubation - +ve 3-6 months+
  • ⇒ IgG antibody after IgM - life
  • Blood count: Leucopenia + lymphocytosis & ↑ESR
• Management
  
  • Symptomatic: fluids, antiemetics, rest
  • Avoid alcohol
• CLD?
  
  • No.
• Prevention
  
  • Vaccine for; travellers, CLD, occupational risk
  • Good hygiene

Question 2

Hepatitis B

• Virus type & structure
• Spread
• Acute S&S
• Chronic S&S & definition
• Tests - Acute & Chronic
• Treatment - Acute, Chronic, Pregnant
• HIV considerations
• Prophylaxis

Answer 2

Virus type;

• RNA Hepadnavirus
• ‘Dane particle’
• Outer envelope - HBsAg
• Inner core - HBcAg & HVeAg

Spread;

• Vertical, blood & sex

Acute S&S;

• Prodrome of flu; fever, malaise, anorexia, nausea, arthralgia
  
  • ​Due to acute infection & immune responce in hepatocytes (cleared in 99%, 1% develop FLD)

Chronic S&S;

• Defintion: HBsAg >6months
• @ Birth;
  
  • ↑immunological tolerance → ↓immune responce
    
    • ↓inflammation, normal LFTs despite +ve HBeAg
    • Lasts for 2-3 decades ⇒ Immune clearance phase
• Immune clearance phase/ fulminant phase;
  
  • ↑HBV DNA & active hepatitis ⇒ fibrosis & cirrhosis + ↑ALT
    
    • Jaundice +/- hepatomegaly, splenomegaly, adenopathy
  • ⇒HBeAg clearance + seroconversion (anti-HBe), ↓HBC DNA & normal ALT
  • ⇒ Fulminant (reactivation phase) ⇒ hepatic necrosis

Tests;

• ACUTE
  
  • HBsAg - 1<6months
    
    • >6months = chronic carrier
  • + HBeAg - 1<3.5months (highly infective)
  • HBsAb - appears late, =immune
  • HBcAb - appears first, IgM HBcAb indicates acute + continuing viral replication
  • HbeAb - appears after HbcAb, =low infectivity
• CHRONIC
  
  • **​HbsAg **>6months = chronic
  • HbeAg persists = chronic?
  • HBV DNA = viral replication

Treatment - only if 3/3 [otherwise monitoring];

1. Chronic HBV infection (HBaAg >6months OR <6months with clinical/epidemiological factors
2. High HBV DNA (>20k IU/ml, indicates viral replication & severity)
3. ↑serum ALT

• AIM: Seroconversion of HBeAg, reduce HBV DNA, normalise ALT/ inflammation
• HbeAg positive
  
  1. Pegylated interferon alfa (IFN) 48wks - SC, inhibits V replication, promotes immune responce
  2. No seroconversion/ relapse ⇒ Tenofovir disoproxil /Entecavir
• HbeAg negative
  
  1. Pegylated interferon alfa (IFN) 48wks - SC, inhibits V replication, promotes immune responce
  2. ↑HBV DNA ⇒ Tenofovir disoproxil /Entecavir
• ​Pregnant
  
  • HBV DNA >107 IU/ml ⇒ Tenofovir disoproxil in 3rd trimester

HIV considerations;

• Co-infection in 10-20%
• TEST!!

Prophylaxis;

• Avoid high-risk factors
• Recombinant yeast vaccine - 10yr immunity
• Combined prophylaxis (anti-HBV immunoglobulin) - after high-risk exposure

Question 3

Hepatitis C

• Virus type
• Spread
• Symptoms & signs
• Tests
• Management

Answer 3

Virus type;

• RNA
• 6 viral genotypes, type 1 is most common in Europe

Spread;

• Bloods (transfusions)
• IV drug users
• Sex
• Acupuncture

Symptoms & signs;

• Acute is mild/ asymptomatic
• 85% → chronic liver disease
  
  • 25% → cirrhosis within 20yrs

Tests;

• HCV AB
  
  • ​<8wks to appear
• ⇒ HCV RNA
• ⇒ HCV genotype
• Biopsy/ Fibrous scan if treatment dependent on degree of hepatitis

Management - Chronic HCV;

• Aim: Sustained viral clearance (no HV RNA for 6 months)
• Treatment
  
  • Pegylated IFN-alfa (SC, 1/wk)
  • Ribavirin (PO, daily)
• Genotypes 1 & 4 - 48wks
• Genotypes 2 & 3 - 24wks

Question 4

Hepatitis D

• Virus type
• Spread
• Symptoms & signs
• Tests

Answer 4

Virus type;

• RNA

Spread;

• Co-infection or sperinfection with HBV

Symptoms & signs;

• Presents as HBV infection or flare up
• ↑risk of acute hepatic failure & cirrhosis

Tests;

• HDV RNA
• IgM anti-HDV in serum

Question 5

Hepatitis E

• Virus type
• Spread
• Symptoms & signs
• Tests

Answer 5

Virus type;

• RNA

Spread;

• Faecal-oral

Symptoms & signs;

• ​Prodrome; fever, malaise, anorexia, nausea, arthralgia
• Jaundice +/- hepatomegaly, splenomegaly, adenopathy

Tests;

• IgG & IgM anti HEV
• HEV RNA