Patient with Jaundice: viral hepatitis Flashcards
HAV
acute illness Very rarely fulminant Never chronic Vaccine No treatment Major risk factor = travel
HBV
Acute illness
Very rarely fulminant
chronic infection yes, but risk depends on age: <1 yrs = 90%, 1-5yrs = 10-25%, adults <5%
Vaccine
Treatment = suppression
Major risk factor = vertical transmission
HCV
Acute illness Fulminant disease rare outside japan Chronic infection likely: 50-85% No vaccine Can be cured Usually transmitted by needle sharing
The difference between hepatitis viruses and other viruses that cause hepatic inflammation
Hep viruses: the liver is the main site of inflammation
Others that also cause hepatic inflammation: EBV, cytomegalovirus, HIV, mumps, yellow fever etc in glandular fever other symptoms and signs dominate over the liver problems
What is IgG is showing up in bloods?
detect antibody response IgG type, then current disease not caused by HPV they must have been infected a while ago
Whereas if they have IgM positive antibodies their current illness will likely be hepA
The difference age of infected patients and whether they will develop chronic infection
High proportion of babies born to mothers with HBV have been infected (vertical transmission) very high proportion of those, >90% will develop in their cells which can lead to liver fibrosis and cirrhosis and liver failure –> liver cancer
If you catch HBV from playing outside with other kids at say age 3 your risk of developing chronic infection has dropped considerably, because the immune system is more mature and able to clear virus. With adults it is quite uncommon to develop chronic infection.
HBV reactivation in chemo patients
When someone gets cleared of hep B they might still have Hep B DNA in their chromosomes because we have enzymes inner cells which if they find free DNA floating around will incorporate into a chromosome = marginally increased risk of liver cancer
BUT if we give chemotherapy there is possibility to reactivate HBV
Note: HAV and HCV don’t get stored in the genome of liver cells
The types of antigens and antibodies we can detect in
HBSAg - vaccine is recombinant surface antigen? / person has been infected Early Ag - lots of virus in their bod Core Ag - never found in serum Anti- HBS = cured or vaccinated anti-HBE = not usually measured Anti- HBC = cured of acute infection IgM
Adult after 5 years of chronic hepatitis will develop?
12-20% cirrhosis = 85% alive at 5 years
20-25% with cirrhosis will decompensated - 15-35% alive at 5 years
6-15% with cirrhosis will develop hepatocellular carcinoma - seldom alive at 5 years unless curable (this from those infected overall is 2-3%)
What to do if you cant determine whether acute or chronic?
Take bloods now and again 6 months later
Treatment of acute viral hepatitis
not required
supportive care
fulminant case -transplant
Treatment of chronic hepatitis
to prevent cirrhosis and cancer
to reduce transmission
HBV - suppress
HCV - cure
HBV treatment
Those with complications those with high ALT (2x normal) Reverse transcriptase inhibitors entecavir tenofivir
How are we preventing HBV?
vaccinate at risk to prevent vertical transmission
- screen pregnant women
- if pos, give HBV Ig at birth, and start vaccination at birth (so 4 doses total)
- Check after last vaccine to check anti-HBS levels
(all infants on the vaccine program get 3 times in their first year anyway)
What actually causes damage to the liver in hepatitis
viral réplication inside the liver cell doesn’t actually damage the cell (unusual for viruses) It is the cytotoxic T cell response that comes along later that causes liver damage approx. 3 months post infection
