AIM • STEP 10
Student Memory Support
Viral Hepatitis A, B and C: Pathogenesis, Diagnosis, Treatment and Prevention
4th Year MBBS • GIT Module • High-yield revision and memory reinforcement
1. High-Yield Flashcards
Tap each question to reveal the answer.
Which hepatitis viruses are mainly transmitted by the fecal–oral route?
Hepatitis A and hepatitis E.
Which hepatitis viruses are most important causes of chronic viral hepatitis?
Hepatitis B and hepatitis C.
What is the main mechanism of hepatocyte injury in viral hepatitis?
Host immune-mediated injury to virus-infected hepatocytes.
Which microscopic changes are typical of acute viral hepatitis?
Ballooning degeneration, lobular mononuclear inflammation and apoptotic hepatocytes.
Which marker supports recent acute hepatitis A infection?
IgM anti-HAV.
Which clinical setting makes acute hepatitis E particularly concerning?
Pregnancy, because acute HEV may be particularly severe.
What does HBsAg indicate?
Current hepatitis B infection.
Which HBV marker is especially useful during the window period?
IgM anti-HBc.
Which HBV serological pattern suggests successful vaccination?
Anti-HBs positive with anti-HBc negative.
What causes the ground-glass appearance of hepatocytes in chronic hepatitis B?
Accumulation of hepatitis B surface antigen within hepatocyte endoplasmic reticulum.
Which test most directly reflects HBV viral replication?
Serum HBV DNA.
Which drugs are major oral options for chronic hepatitis B?
Tenofovir and entecavir.
What confirms current active hepatitis C infection?
Detectable HCV RNA.
Which morphological clues may support chronic hepatitis C?
Portal lymphoid aggregates, interface hepatitis and steatosis.
Which HCV drug class includes velpatasvir and ledipasvir?
NS5A inhibitors.
Which findings in acute hepatitis should trigger urgent referral?
Encephalopathy, significant coagulopathy, worsening jaundice or other evidence of severe hepatic dysfunction.
2. Mnemonics
Mnemonic Title: Transmission Divider
A/E = Alimentary • B/C = Blood
Meaning: Hepatitis A and E are mainly fecal–oral; hepatitis B and C are mainly transmitted through blood or relevant body fluids.
Mnemonic Title: HBV Serology Core
SAC
Meaning: Surface antigen = current infection; surface Antibody = immunity; Core antibody = natural viral exposure.
Mnemonic Title: HCV Clinical Pathway
SCAR
Meaning: Screen with anti-HCV → Confirm with HCV RNA → Assess liver fibrosis → Rx with direct-acting antivirals.
3. Memory Tables
Table 1: Viral Hepatitis Quick Comparison
| Feature | HAV | HEV | HBV | HCV |
|---|---|---|---|---|
| Main route | Fecal–oral | Fecal–oral | Blood/body fluids | Mainly blood |
| Chronicity | No usual chronic disease | Usually acute | Possible | Common |
| Key marker | IgM anti-HAV | IgM anti-HEV / HEV RNA | HBV serology + HBV DNA | HCV RNA |
| Major prevention | Hygiene + vaccination | Safe water/sanitation | Vaccination + exposure control | Blood-exposure control |
Table 2: HBV Serology Memory Table
| State | HBsAg | Anti-HBs | Anti-HBc | Memory Clue |
|---|---|---|---|---|
| Vaccinated | − | + | − | Surface antibody only |
| Acute infection | + | − | IgM + | Recent natural infection |
| Window period | − | − | IgM + | Core IgM is key |
| Recovered | − | + | + | Natural infection + immunity |
| Chronic infection | + | − | + | Persistent surface antigen |
4. Rapid Revision Points — Last-Minute Revision
Must Remember:
- Acute viral hepatitis produces a hepatocellular enzyme pattern with marked ALT/AST elevation.
- HAV and HEV are mainly enterically transmitted; HBV and HCV are mainly blood/body-fluid related.
- HBV liver injury is mainly immune mediated rather than strongly directly cytopathic.
- Persistent HBsAg beyond six months supports chronic HBV infection.
- HBeAg generally reflects active replication; HBV DNA is the direct measure of viral load.
- Anti-HCV indicates exposure, but HCV RNA identifies current infection.
- Chronic HCV may show portal lymphoid aggregates and steatosis.
- Tenofovir and entecavir suppress HBV polymerase activity and are commonly used long term.
- Modern HCV treatment uses finite direct-acting antiviral combinations.
- Encephalopathy or major coagulopathy in acute hepatitis is a red flag requiring urgent specialist care.
5. Clinical Memory Hooks
Child with mild illness after contaminated food →
hepatitis A may be mild or clinically inapparent in children.
hepatitis A may be mild or clinically inapparent in children.
HBsAg positive with high HBV DNA →
current infection with active viral replication.
current infection with active viral replication.
Anti-HCV positive but RNA undetectable →
previous exposure without current detectable infection.
previous exposure without current detectable infection.
Jaundice with confusion and prolonged INR →
severe hepatic dysfunction / possible acute liver failure requiring urgent referral.
severe hepatic dysfunction / possible acute liver failure requiring urgent referral.
6. Starred High-Yield Exam Points
- ⭐ IgM anti-HBc is the key serological marker during the HBV window period.
- ⭐ Anti-HBs without anti-HBc strongly suggests immunity from HBV vaccination.
- ⭐ Ground-glass hepatocytes are a classic morphological clue to chronic hepatitis B.
- ⭐ HBV DNA is the best direct marker of ongoing HBV replication.
- ⭐ HCV RNA, not anti-HCV antibody alone, confirms active hepatitis C infection.
- ⭐ Pegylated interferon can cause flu-like symptoms, marrow suppression, mood disturbance and thyroid dysfunction.
- ⭐ Hepatitis B is vaccine-preventable; routine hepatitis C prevention depends mainly on avoiding infected blood exposure.