Hepatitis Micro Flashcards
Which hepatitis viruses can cause only acute?
A and E
Which hepatitis viruses can cause chronic disease and therefore hepatocellular carcinoma?
HBV, HCV, HDV
Hepatitis A family
Picornaviridae
Hepatitis E family
Caliciviridae
HAV structure
+ ssRNA
Which herpes virus is associated with significant pregnancy mortality?
E
HEV structure
+ ssRNA
Which hepatitis virus has the fastest incubation?
HAV
Salad bars?
HAV
Who is at risk for HAV?
Native Americans, or during outbreaks:
Diners, day care workers, gay men, IV drug user
HBV family
Hepadnavirus
Which one has the unique life cycle?
HBV
What are the four major proteins of HBV?
DNA polymerase
HBsAg
HBcAg
X antigen
What kind of enzyme is DNA polymerase?
HBV
What is HBV’s attachment protein?
HBsAg
What is HBcAg?
The core antigen secreted derivative of HBcAg
An important serologic marker but measured as HbeAg
How can HBV be transmitted?
Sexually
Blood
Parenteral
Explain HBV replication
- Enters
- Completes second strand ds synthesis
- Translocates to nucleus and makes mRNA for its four proteins AND a full-length + RNA copy of genome
- Reverse transcriptase in cytoplasm uses it to make more
- Results in partially ds DNA molecule
- *dsDNA virus with an RNA intermediate
Where is HBV endemic?
China
sub-Saharan Africa
Describe HBV pathogenesis
More insidious onset
Close to 16 weeks incubation
Serology: surface antigen E
Three phases: incubation, symptomatic, convalescent
Positive HBsAg tells you..
Carrier or acute infection
Anti-HBs tells you…
Had HBV previously, or received vaccine
HBeAg tells you…
At increased risk for transmission (active marker)
Lingers positive after symptoms resolve
Anti-HBc tells you…
Past infection
IgM anti-HBc tells you…
Acute or recent infection
HDV structure
circular ss RNA genome
incomplete
must incorporate HBsAG to infect hepatocytes
HCV family
Flaviviridae
Which hepatitis viruses has all those different subtypes
HCV
Why can chronic HCV keep appearing in the same patient?
Hypermutable variation so that immune system has to generate new responses
Done via E2 protein
In HBV and HCV, what leads to the liver disease?
NOT virus-medaited cytolysis
It’s immune destruction
Causes of chronic viral hepatitis
40% HCV
20% HBV
What are the three phases of chronic hepatitis?
Immune tolerance
Immune clearance: symptoms start
Residual phase: after seroconversion
Most patients who get infected with HBV…
resolves 90%
What are some extrahepatic manifestations of chronic HBV?
Polyarteritis nodosum
Glomerulonephritis
Most patients who get infected with HCV…
will get chronic disease unless treated
85%
HAV dx
Anti-HAV IgM
HBV dx
HBsAg, HBeAg, HBe antibody, HBV DNA
HCV dx
core antigen, RNA
Havrix vaccine
Inactivated
Age 1-2 yrs
for HAV
Combo vaccine
HAV and HBV
18 yrs + only
Havrix plus recombinant HBV
