MICRO: Hepatitis Flashcards
Which hepatitis viruses are non-enveloped?
HAV and HEV
Who is most affected by HAV?
Adults are 70% symptomatic
Children often subclinical (10%)
Do antibodies appear before of after infection in HAV?
With rising ATL, IgM rises
What tests are done to diagnose HBV?
HBsAg
HBcAb
HBsAb
What test is used to diagnose HCV?
HCV RNA (antibodies develop late)
What test is used to diagnose HDV?
Anti-HDV serology
How many genotypes of HBV?
10 (A-J)
A Dane particle is characteristic of which infection?
HBV
How long does HBV need to last to be chronic?
6 months
What infection despite being asymptomatic in children has long term consequences?
HBV - 90% of infected neonates develop chronic HBV
What % of adults with HBV develop chronic infection?
10%
Why is testing for HBsAb not useful in acute infection?
Only appears later - but HBcAb is present early (IgM type)
Why can you not use IgM anti-HBc to diagnose acute infection in HBV?
It could also mean chronic infection
What are the 2 stages of HBV infection?
HBeAg +ve or -ve
What are the 2 stages of HBV infection?
HBeAg +ve or -ve
Why is testing of HBV DNA levels helpful?
Increasing levels mean higher risk of HCC and cirrhosis (REVEAL study)
What is the main treatment for HBV?
Interferon-alpha or antivirals (ETV, TDF,TAF)
If mother is ANTI-HBeAg positive, does the baby need to receive HBIG?
No, only vaccination
What antibody protects from HBV?
Anti-HBsAg
What % of HCV becomes chronic?
70% (higher in males)
What is the tx for HCV?
Peginterferon alpha 2b + ribavirin –> 90% cure rate
What is SVR12?
If at 12 weeks after stopping treatment the virus is gone then you are cured
What is the significance of different genotypes in HCV?
Genotype 1 is harder to treat than non-1
What is the significance of different genotypes in HCV?
Genotype 1 is harder to treat than non-1
What DAA targets are used in HCV?
non-structural proteins 3/4, 5a and 5b
What is NS3/4 the target of ?
Protease inhibitors - “previr”
What is NS5a the target of?
NS5a inhibitors - “asvir”
What is NS5b the target of?
NS5B inhibitors (RNA polymerase inhibitors) - “buvir”
What is the disadvantage of NS3/4 protease inhibitors over the others?
Only for Genotype 1, low barrier to resistnce and interactions
Which NS targetting drugs target all cellular processes in HCV (processing, replication, assembly)?
NS5a inhibitors - “asvir”
Which NS targeting drugs target all cellular processes in HCV (processing, replication, assembly)?
NS5a inhibitors - “asvir”
What is it called when you have HBV but then get HDV too?
Superinfection
Is HBV-HDV co-infection or superinfection more serious?
Superinfection - 80% risk of c hronic infection
What are the genotypes of HEV?
G1 + 2 = obligate human pathogens
G3 + 4 = zoonotic (i.e. must have come from an animal)
UK is endemic of which HEV genotype?
Genotype 3
Which population is most at risk of HEV?
Pregnant women –> fulminant hepatitis
What are some CNS complications of HEV?
Bell’s palsy
GBS
Also has haem, renal, cardiac, bone, thyroid and pancreas complications. Case reports only for some.
Which hepatitis virus is associated with MSM?
HAV
Which hepatitis virus is associated with shellfish and sausage consumption?
HEV
How is HEV diagnosed?
Anti-HEV serology (anti-HEV IgM rises acutely)
How is HEV diagnosed in the immunocompromised?
HEV PCR
Where can HEV persist for longer?
Stools
Which hepatitis virus would chef’s not be allowed to prepare food for a few weeks?
HEV
