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45 Cards in this Set
- Front
- Back
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Main connected of hepatitis viruses
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target hepatocytes (most other things different)
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Virus family of Hep A
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Picornavirus (picoRNA)
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Virus type of Hep B
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Hepadnavirus (hepaDNAvirus)
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Which hepatitis viruses cause acute hepatitis before immunity?
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A/E
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Why can HepD only affect someone in partnership with another hepatitis virus?
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surface coat of HepB
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Symptoms for hepatitis presentation?
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dark urine (biliary salts spill over), nausea, white stools, RUQ pain
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Enterically transmitted Hep viruses
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A/E
Shed from liver in bile -virions are non-enveloped and stable (shed through stool) |
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Enveloped hepatitis virus environment?
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Not stable
cause chronic infections transferred parenterally or via mucosal (sexual) |
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Morbidity and mortality from HBV+HCV from what?
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cirrhosis
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serum markers of hepatitis
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ALT, AST, bilirubin, alkaline phosphatase
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Hepatitis A virus facts
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+strand RNA
stable to heat and acid (has to go through stomach) grows in cell culture (led to inactivated vaccine) |
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Where does picornavirus replicate?
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totally in cytoplasm
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How does Hepatitis A virus travel through the body?
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in envelope, protecting from Ab
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Transmission of HepA
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fecal-oral
point-source and person-to-person Incubation of 30 days |
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Complications of HepA hepatitis
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fulminant hepatitis
relapsing hepatitis cholestatic hepatitis |
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Dx of HepA
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return from developing country, no hx of immunization
50% will be symptomatic Can measure IgM anti-HAV for more immediate presence |
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What is the window for intervention post-infection?
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Up to 2 weeks to prevent disease with immune globulin
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Difference between HepA and HepC
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Envelope present on HepC, leads to persistence
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What takes place in the membranous web?
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Viral RNA synthesis, which uses many host factors to promote replication
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What release system does HepC hijack?
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VLDL release, which makes it more difficult to target within body
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Why is it difficult to create HepC vaccine?
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Can't grow in culture
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What RNA replicons have been generated to express HCV?
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neomycin phosphotransferase
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Describe the number of genotypes of HCV and which afflicts the US.
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6 genotypes, #1 is in US, hardest to treat
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Acute presentation of HepC histologically
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necroinflammation steatosis
leads to progressive fibrosis cirrhosis |
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Clinical outcomes from HCV infection
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30% spontaneously recover
Most others cured through triple therapy, remainder lead to cirrhosis and hepatocellular carcinoma |
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Liver cancer is commonly associated with what infection?
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HCV
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Mechanism isn't known for HCV. What most likely happens?
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Disrupts innate immune response, adaptive immune response
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Pathogenesis of HCV infection
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Immune response causing inflammation without clearing disease (stims stellate cell to lay down collagen)
-Alcohol promotes risk, as does diabetes and obesity (pro-inflammatory state) |
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Does HCV integrate its genome? How does it continue?
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No, doesn't integrate. Always replicates. If you stop replication, can eliminate virus.
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traditional Tx for HCV
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interferon-alpha + ribavirin (weekly injections)
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Newer tx for HCV
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Direct-acting antivirals (proteases, polymerases, miRNA-22 targets)
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Concerns about new anti-viral monotherapy
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resistant variants with quasispecies (RdRP errors)
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Ways to counteract resistance in HCV
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combo txs
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Type of HepB replication
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DNA virus that uses RNA intermediate (borderline RT)
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What components make up the HepB virus?
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spheres and tubules (have HBsAg)
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DNA structure of HepB
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Partially double stranded DNA
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What tx for HepB is used?
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RT inhibitors, which is suppressive, but not curative (leaves cccDNA)
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Antigen/Ab response to Acute HepB virus
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HB surface antigen measureable (HBeAg is secreted and soluble, signifies robust virus)
IgM anti-HBc (core-lasts about 6 mos) |
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Who doesn't clear HepB infection?
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Immunosuppressed, older individuals
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If immunized, which antibodies would you see for HepB?
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Anti-HBs (just surface)
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In Chronic HepB, what would you expect to see in terms of serology?
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elevated ALTs, high Anti-HBc, HBsAg, possibly HBeAg (if replicating still), possibly Anti-HBe (if less severe)
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4 types of HepB transmission
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-neonatal (high risk of life-long carrier, prevent by immunization)
-horizontal (young kids, saliva?) -Sexual (common, traumatic sex) -Parenteral (injection, nosocomial) |
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High HDsAg prevalence
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sub-Saharan Africa, China
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Goal of antiviral therapy for Chronic HepB
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Suppress infection, prevent cirrhosis, liver failure
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Next goal of HepB vaccine, target?
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cccDNA
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