Hepatitis B Flashcards
What is the first marker of Hepatitis B infection?
surface antigen (HBsAg) is the first marker to appear and causes the production of anti-HBs (antibodies)
What results of the blood test will imply acute Hepatitis B infection?
Presence of HBsAg antigen present in the first 1 - 6 months
How is chronic hepatitis B infection diagnosed?
The presence of HBsAg antigen for more than 6 months
What does the presence of Anti-HBsAG imply?
- Implies immunity from either exposure or immunity 2. Negative in chronic disease
What does the presence of Anti-HBeAg imply?
HbeAg results from breakdown of core antigen from infected liver cells as is, therefore, a marker of infectivity
What does the presence of Anti-HBcAg imply?
- Implies previous (or current) infection so exposure from infection and not immunisation. 2. IgM anti-HBc appears during acute or recent hepatitis B infection and is present for about 6 months. 3. IgG anti-HBc persists
What antibodies will be present in the case of previous immunisation?
anti-HBs positive, all others negative
What antibodies will be present in the case of previous hepatitis B infection (> 6 months ago), not a carrier?
anti-HBc positive, HBsAg negative
What antibodies will be present in the case of previous hepatitis B infection and now a carrier?
anti-HBc positive, HBsAg positive
How is Hepatitis B spread?
is spread through exposure to infected blood or body fluids, including vertical transmission from mother to child.
How long is the incubation period for Hepatitis B?
1 - 6 months incubation period
Name 3 symptoms of Hepatitis B infection?
- Fever 2. Jaundice 3. Elevated liver transaminases
Name 3 complications of Hepatitis B infection?
- chronic hepatitis (5-10%). ‘Ground-glass’ hepatocytes may be seen on light microscopy 2. fulminant liver failure (1%) 3. hepatocellular carcinoma
Why is it important to screen those with a hepatitis B infection?
As chronic hepatitis B is often asymptomatic or only produces general malaise symptoms
Name 6 groups of people at risk of Hepatitis B infection?
- Household contacts of infected persons 2. Sexual contacts of infected persons 3. IV drug users 4. Those with multiple sexual partners 5. Those with a history of sexually transmitted disease 6. Homosexual men 7. Inmates of correctional facilities 8. Individuals with chronically elevated ALT/AST levels 9. People infected with HIV or HCV 10. Renal dialysis patients 11. Pregnant women
When are children vaccinated against Hepatitis B?
Vaccinated at 2, 3 and 4 months of age
How is immunity against Hepatitis B tested for in people with occupation exposure?
- Anti HBs levels should be checked 1 - 4 months after primary immunisation
How are anti - HsB levels interpreted in people being tested 4 months after primary immunisation due to occupational exposure?
> 100 Indicates adequate response, no further testing required. Should still receive booster at 5 years 10 - 100 Suboptimal response - one additional vaccine dose should be given. If immunocompetent no further testing is required < 10 Non-responder. Test for current or past infection. Give further vaccine course (i.e. 3 doses again) with testing following. If still fails to respond then HBIG would be required for protection if exposed to the virus
What factors effect disease course?
- Gender 2. Age at infection 3. Hepatitis B viral load 4. Duration of infection
How is Hepatitis B managed?
pegylated interferon-alpha used to be the only treatment available. It reduces viral replication in up to 30% of chronic carriers.
Can hepatitis B be transmitted by breast feeding?
No, it can’t unlike HIV
