- all are caused by RNA virus' except hepatitis B, which is a DNA virus
- B and C are spread by blood/sexual contact
- A and E are spread by the faecal-oral route
- Hepatitis D essentially is only ever found as a co-infection, never alone.
So to explore the 3 most popular MRCP 'flavours' in more depth....
Hepatitis A:
- spread faeco-orally, so look out for questions featuring backpackers returning home
- incubation period is 2-6 weeks
- presents as fever, malaise, nausea
- patient likely to be jaundiced and may have hepato/splenomegaly
- treatment is supportive
- patients generally make a full recovery
Hepatitis B:
- symptoms are similar to hep A
- incubation period is longer at 1 - 6 months
- spread is blood/bodily fluids - questions likely to hint at male business traveller or other innuendo
- important to fully grasp the various antigens and their meanings:
- HBsAg: present for 1-6 months after exposure; if present for >6 months patient is a carrier
- HBeAg: present for 1.5-3 months after exposure and is marker of high infectivity
- anti HBC IgM - signifies acute infection/carrier
- anti HBC IgG - may be acute infection, carrier or cleared infection
- anti HBS - if present with anti HBC suggests recovered from hep B and naturally immune; if present alone suggests hep B vaccination
- complications of hepatitis B include:
- 5-10% chronic hepatitis
- glomerulonephritis
- increased risk hepatocellular carcinoma
- cryoglobulinaemia
Hepatitis C:
- is spread by blood/sexual contact
- blood pre 1991 wasn't screened for hep C
- <20% get an acute hepatitis but 80% get chronic hepatitis
- breast feeding is NOT contraindicated (a common MRCP fascination for some reason)
- complications:
- 80% chronic hepatitis
- 20% cirrhosis
- increased risk hepatocellular carcinoma
- Treatment: IFN alpha and ribavirin
After that wizz through some high-yield viral hepatitis facts lets move on to Peutz Jegher Syndrome
