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Viral hepatitis (A, B, C, D, E)
Hepatitis B is read from three markers — HBsAg (infection), anti-HBs (immunity) and anti-HBc (past contact; IgM = acute); hepatitis C is diagnosed with anti-HCV, confirmed with HCV RNA and treated in every patient with direct-acting antivirals, with cure rates above 95%.
Why it matters in the exam
The hepatitis B serology question is one of the fixed exam questions. The candidate must recognise: vaccinated — anti-HBs only; recovered from infection — anti-HBs and anti-HBc; acute infection — HBsAg and anti-HBc IgM; "window" — anti-HBc IgM only; chronic infection — HBsAg persisting for more than 6 months. HBeAg and the HBV DNA level reflect replication. In chronic infection tenofovir or entecavir is given when HBV DNA is above 2000 IU/mL with a raised ALT or significant fibrosis, and in cirrhosis with any detectable DNA. Remember prophylaxis before strong immunosuppression (for example rituximab) in HBsAg carriers and in anti-HBc-positive patients, and for the baby of a carrier mother — vaccine and immunoglobulin within 12 hours.
In hepatitis C: a positive anti-HCV needs HCV RNA to separate active from cleared infection. Every patient with positive RNA is treated with pan-genotypic drugs (sofosbuvir/velpatasvir for 12 weeks or glecaprevir/pibrentasvir for 8 weeks), and HBV is checked before treatment because of the risk of a flare. Hepatitis A spreads faecal-orally and causes only acute disease; hepatitis D occurs only with B; hepatitis E is linked to undercooked pork and is dangerous in pregnancy. Acute liver failure (INR of 1.5 or more with encephalopathy) calls for transfer to a transplant centre, and in paracetamol poisoning — N-acetylcysteine.
Key points
- B: HBsAg = infection; anti-HBs = immunity; anti-HBc = contact (IgM = acute).
- Chronic B: HBsAg over 6 months; tenofovir or entecavir by DNA, ALT and fibrosis.
- C: anti-HCV then RNA; DAA for all, cure above 95%.
- B prophylaxis before rituximab; baby — vaccine and immunoglobulin within 12 hours.
- A and E are acute; D only with B; E is dangerous in pregnancy.
Summary table
| Pattern / virus | Markers | Meaning | Action |
|---|---|---|---|
| Vaccinated against B | Anti-HBs only | Immunity from vaccine | No treatment needed |
| Recovered from B | Anti-HBs + anti-HBc | Past infection | Prophylaxis before rituximab |
| Acute B | HBsAg + anti-HBc IgM | Acute infection | Supportive; treat only severe acute disease |
| Chronic B | HBsAg over 6 months | Chronic carriage | Tenofovir or entecavir by DNA (above 2000 IU/mL), ALT and fibrosis |
| C | Anti-HCV then HCV RNA | Positive RNA = active infection | DAA for all: 12 weeks or 8 weeks |
| A, D, E | A faecal-oral; D only with B; E pork and pregnancy | A and E are acute | Vaccines for A and B |
A free exam question
איזה מהוירוסים הבאים עובר, בשכיחות הגדולה ביותר, במהלך הלידה ?מהאם לילוד (the question as examined, in Hebrew)
- א. HBV
- ב. HCV
- ג. HEV
- ד. HDV
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Sources
- EASL Clinical Practice Guidelines on the management of hepatitis B virus infection, 2017 — Serology, phases and indications for treatment
- AASLD-IDSA HCV Guidance: Recommendations for Testing, Managing, and Treating Hepatitis C, 2023 — Pan-genotypic DAA regimens
- Harrison's Principles of Internal Medicine, 21st edition (2022) — Acute Viral Hepatitis; Chronic Hepatitis
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.