MI: Viral Hepatitis Flashcards
Name some primary and secondary hepatotropic viruses?
Primary - hepatitis A, B, C, D, E
Secondary - EBV, CMV, HIV, parovirus B19
What type of virus is hepatitis A?How is hepatitis A spread?
Single-stranded RNA virus
Faecal-oral
- Person-to-person (sex)
- Contaminated food/drink
What is the incubation period for hepatitis A?
2-6 weeks (usually 4 weeks)
What are symptoms of hepatitis A infection?
Symptoms of acute hepatitis
- Non-specific - fever, fatigue, abdominal pain, malaise, loss of appetite
- Elevated bilirubin - jaundice, pale stools + dark urine, pruritius
Describe the natural history of hepatitis A infection.
- 2-6 weeks after the infection you will develop hepatitis (transaminitis)
- This will be accompanied by a rise in IgM
- A more gradual rise in IgG will follow
NOTE: hepatitis A infection is often subclinical
What is the diagnostic test for acute hepatitis A?
Anti-hepatitis A IgM (anti-HAV IgM)
- Only request if symptomatic patient has if ALT >500u/L)
- If <500 may get false negative because antibody titres have not risen enough
may be negative in 1st week
Which antibodies will be present if someone has received a hepatitis A vaccine?
Anti-HAV IgG
(if infected, they will have high IgM and IgG, but no transaminitis)
When are those with hepatitis A infectious?
2 weeks before until 1 week after onset of jaundice
How is HAV treated?
Supportive, no chronicity
What type of virus is hepatitis B?How is hepatitis B transmitted?
DNA virus
- Sexually transmitted
- Blood products
- Mother-to-baby (eAg is the biggest predictor)
What is the incubation period of hepatitis B?
2-6 months
What are 3 possible courses of hepatitis B infection in adults?
- Clearance (90%)
- Chronic infection (10%)
- Fulminant liver failure (0.5-1%)
40% are symptomatic
What is the course of HBV infection in children under 5 ?
Asymptomatic, 90% develop chronic infection
What the biochemical definition of chronic HBV infection?
HBsAg positive > 6 months
What do the presence of the following antigen/antibodies indicate:
- HBsAg
- HBeAg
- Anti-HBc IgM
- Anti-HBc IgG
- Anti-HBe IgG
- Anti-HBs IgG
What are some possible consequences of chronic HBV infection?
- Hepatocellular carcinoma
- Cirrhosis