Exam 5: Viral Hepatitis Flashcards
what is hepatitis
inflammation of the liver
what is viral hepatitis
hepatitis caused by one of at least five distinct viruses
How is hepatitis delta virus developed
requires HBV co-infection for replication and expression
How is hepatitis E virus location
Primarily occurs in India, Asia, Africa, and Central America
What type of virus is HBV
DNA
What is the primary virus of hepatitis
RNA
Viral hepatitis acute illness characteristics
Nausea, anorexia, fever, malaise, and abdominal pain
Jaundice or elevated liver transaminases
Which hepatitis can produce chronic infection
HBV and HCV
Viral hepatitis chronic infection characteristics
Subclinical to cirrhosis or hepatocellular carcinoma (HCC)
HAV main transmission
fecal-oral
HBV main transmission
Blood
sexual
HCV main transmission
Blood
HAV perinatal transmission
Does not happen
HBV perinatal transmission
Yes
HCV perinatal transmission
Yes
HAV most common risk factor
direct contact with someone with HAV
HBV most common risk factor
born to infected mother
HCV most common risk factor
Injection drug use
HAV chronic infection
Does not happen
HBV chronic infection
Yes
HCV chronic infection
Yes
HAV course of infection
acute, then resolved
HBV course of infection
Acute, then sometimes chronic
90% of infants
25-50% of children ages 1-5
5% of adaults
HCV course of infection
Acute, then usually chronic
>50% develop chronic infection
HAV treatment of chronic infections
N/A
HBV treatment of chronic infections
Yes, not curative
HCV treatment of chronic infections?
Yes, curative
HAV protective immunity
Yes
HBV protective immunity
Yes
HCV protective immunity
No
HAV vaccine available
Yes
HBV vaccine available
Yes
HCV vaccine available
No
HAV incubation period
28 days (range 15-50 days)
HAV virology
picornavirus that replicates in the liver, excreted in the bile, and is shed in the stool
HAV symptoms
Abrupt onset, usually lasts less than 2 months:
fever, fatigue, loss of appetite, jaundice, joint pain
HAV death rate
Rarely fatal
HAV diagnostic testing
IgM anti-HAV in serum (usually detectable in 15-20 days)
or
HAV RNA in serum or stool
What remains detectable providing lifelong immunity in HAV
IgG anti-HAV
what is used to assess immunity in HAV
Total anti-HAV (measuring both IgG and IgM)
Role of antiviral agents in HAV
No role
HAV management
supportive care only
How many doses of HAV vaccine
Two: given at 0 and 6-12 months
HBV virology classification
hepadnavirus
HBV pathogenesis
virus enters the liver through the bloodstream, replicates in the liver
What can HBV NOT be spread by
FOOD Water Sharing eating utensils breastfeeding kissing
HAV or HBV: diarrhea
HAV
HBV acute symptoms
same as HAV but with no diarrhea
HBV chronic infection symptoms
typically asymptomatic until onset of cirrhosis, end-stage liver disease or HCC
HBsAg marker
Hep B Surface antigen
HBsAg significance
Is the patient infectious?
Marker of presence of ongoing infection
anti-HBs marker
antibody to hepatitis B surface antigen
anti-HBs significance
Is the patient immune?
Marker of immunity (indistinguishable whether acquired from disease or vaccination)
Total anti-HBc marker
antibody to hepatitis B antigen
Total anti-HBc significance
Has the patient been exposed to the virus?
Marker of exposure to the infection: persists for life, does not account for time since infection
IgM anti-HBc marker
Immunoglobulin M class of antibody to hepatitis B core antigen
IgM anti-HBc marker significance
Has the patient been recently exposed to the virus?
Marker of acute or recently acquired HBV infection (can give false positives)
HBeAg marker
Hepatitis B e antigen
HBeAg significance
Is the virus actively replicating?
Marker of high infectivity in acute or chronic HBV infection (corresponds to viral replication)
anti-HBe marker
antibody to hepatitis B e antigen
anti-HBe significance
Has the virus recently stopped replication?
Marker of loss of viral replication and lower levels of virus
HBV acute infection management
No treatment available
Supportive care