Hep Flashcards
Hepatitis G classification
RNA virus Icosahedral Nucleocapsid Enveloped SS (+) Nonsegmented Flavivirdae
Hepatitis G is in the same family as these two virusus
HCV
YFV
How does one usually acquire Hep G?
Exposure to contaminated blood products (multiple blood transfusions, IV drug users)
If one has Hep G they may be coinfected with one of these viruses (2)
HBV
HCV
(or both)
How is Hepatitis G diagnosed
detection of the genome by RNA via RT PCR
Which two Hep viruses are Fecal to Oral transmitted?
A and E
Think acute infections
Which three Hep viruses are through blood/sexual contact
HBV, HCV, HDV
Short incubating viruses (2-8 weeks)
HAV and HEV
Long incubating viruses (2-24 weeks)
HBV, HCV and HDV
Can all Hep viruses cause an acute infection?
Yes
Only HBV, HCV and HDV will progress to chronic
Hepatitis A classification
RNA virus Icosahedral nucleocapsid SS (+) non segmented Picoraviridae Enterovirus
Describe the structural features of Hepatitis A
Small, naked virus
VPg protein is attacked at the genome containing polyA tail
What happens after the RNA for Hep A is translated?
RNA is translated all at once then cleaved down to subsequent products that have specific functions (example : structural vs non structural)
How can Hep A virus be inactivated?
Chlorine treatment in drinking water
Formalin
UV radiation
Mechanism of Hep A infection
Fecal to oral
Infects cells expressing HAV cell receptor 1 (HAVCR1)
Virus replicates in large quantities in liver and shed in stool 10 days before onset of jaundice
What actually causes the pathogenic effects of hepA?
Hep A isn’t cytotoxic
It’s the immune response to the viral infected liver cells (by cytotoxic T cells)
Most common cause of liver failure in the US (and subsequent transplant)
Chronic HCV
How do viral hepatitis infections often present?
febrile illness of prolonged duration jaundice fatigue abdominal pain loss of appetite nausea vomiting
Hepatitis infection labs
High AST, ALT, BIL and total protein
Why can arthritis and rash occur with hepatitis
immune complex associated vascultis
Risk factors for HAV
contaminated seafood or imported berries
Risk factors for HBV
Multiple sexual partners and unprotected intercourse
Risk factors for HCV
intravenous drug use and blood transfusion (prior to 1990)
Entecavir
HBV
Guanosine nucleoside analog that inhibits HBV polymerase
Pegylated interferon alpha 2A
HCV + AIDS/KS
HBV
Cytokine with immunomodulating, antineoplastic and antiviral properties
Tenofovir disoproxril fumerate (TDF)
HBV
Inhibits activity of HBV polymerase by competing with dATP causing DNA chain termination
Brief review of ELISA
HAV IgM serum of individual
HAV antigen on plate.
Add serum
If ab against the HAV virus, will bind and stick
Then use second ab that changes color
anywhere with color has the IgM antibody from the individual
Where does peak liver damage occur in HAV
When the CTL and IgM response occurs
Exposure prophylaxis for HAV?
If healthy (1-40 yo) - HepA vaccine Others get pooled human immunoglobin
When is hep E especially dangerous
3rd Trimester of tregnancy
Hep E classification
RNA
Icosahedral Nucleocapsid
SS (+) Nonseg. Genome
Caliciviridae
Why is Hep E dangerous in pregnant women
Immunological and hormonal factors - T cell imbalance
HBV classification
DNA virus Icosahedral Enveloped DS circular DNA (VII) Hepadnaviridae Orthohepadnavirdae
What is the ‘infectious’ virion in HBV
Dane particle
