Viral Hepatitis Flashcards
Which viral hepatitis are “infectious” and “serum”
A and E are enterically transmitted
BD and C are prenterally transmitted
How is HAV infection different in children v. adults
children are often asymptomatic, adults usually have self-limited jaundice
Who is at most risk of transmission in US for HEV?
entirely transmitted, often through contact with swine or in pregnant women or immunocompromised who eat meat that is not fully cooked (infection via either zoonotic or ingestion)
PCR serum or stool
Hepatic damage in HBV is mediated how?
HLA class 1 restricted CTL response directed at HBcore antigens on HBV infected hepatocytes; HBV integrates into the human genome (can cause activation of protoncogenes)
Contrast transmission of HBV in high and low endemic areas.
high endemic: vertical transmission
low endemic: adult transmission through sex, IV use
T/F Only those who have developed anti-HBS antibodies are immune.
true: acquired via vaccination or clearing of acute infection
Who are most likely to progress to chronic disease from HBV infection
children are much more likely than adults 90%v 10%
List risk factors for progression of chronic liver disease.
longer duration of disease older age, male family history aflatoxin (africa) co-infection HCV, HDV, HIV alcohol use higher viral load reccurent episodes of reactivation genotype (C worse than A)
leads to higher risk of HCC- higher viral load
How do you screen for HCC?
ultrasonography or CT/MRI scanning AND alpha fetoprotein every 6mo (screen with our without fibrosis)
Coinfection of ______ usually resolves but superinfection frequently causes chronic disease and chronic hepatitis.
HDV, infection only possible in the presence of HBV
How do you treat neonates born to mothers with active HBV infection?
babies get HBIG within 12hr of birth and HBV vaccine at same time at a different site (another arm) is 85-95% protective
What are the two classic treatments of HBV?
antivirals aimed at surprising or destroying HBV by interfering with viral replication
immune modulators aimed at helping the human immune system to mount a defense against the virus (serious side effects, expensive, shorter duration)
1st line: pegaylated INFaa2a, enticer and tenofovir
lamivudine inhibits HBV DNA polymerase, resistance develops
HCV has 6 major genotypes, in the US the most common genotypes are?
1a and 1b
Describe the pathogenesis of HCV.
while it does not integrate into host cell, it does cause a CTL that does not clear the virus, leads to hepatic inflammation, fibrosis and in some cirrhosis
there are many quasi species due to the frequency of gene sequence variation
Describe the prevalence of HCV in the US, how is it most commonly acquired?
infection peaked in the late 70’s early 80’s
IV drug use 60%, Sexual 15%, transfusion (before 1992) 10%, 15% other/unknown, dialysis
T/F HCV is transmitted more often in vaginal delivery than C-section.
F transmission has no association with delivery method or breast feeding
transmitted only from women who are HCV RNA positive at delivery (infected infants do well)
What are the clinical symptoms of HCV?
often asymptomatic
can have mild fatigue, nausea, poor appetite, myalgia, arthralgia and mild RUQ discomfort
Who is recommended for HCV screening in the US?
those that have an increased risk for infection or those in need for exposure management
CDC recommends testing baby boomers born between 1945-1965
testing done by EIA detecting antibody, confirm with HCV RNA PCR
Do more of those with HBV or HCV go on to develop liver cirrhosis?
~17% of patients with HCV go on to develop cirrhosis
90% of children with HBV develop cirrhosis
and 10% adults with HBV develop cirrohosis
Which factors promote progression or severity of HCV infection?
increased alcohol intake age >40yrs HIV co-infection male gender other co-infeciton obesity, insulin resistance, increased metabolic syndrome
Compare the risk of cirrhosis in HBV and HCV.
patients with HCV only develop HCC after development of cirrhosis, those with HBV can develop it any time
**HCV is the leading indication for liver transplantation in the US, patients should be referred for treatment if they have evidence of decompensated portal HTN
How is HCV treated?
combo therapy of direct acting antiviral agents: protease inhibitors, NS5a inhibitors and polymerase inhibitors
most effective tx: DAA+ RBV +/-PEGIFN 12weeks
newer agents have a shorter course and are very well tolerated but are VERY EXPENSIVE
T/F After exposure, immunoglobins and vaccine should be administered.
IgG are not effective in preventing HCV after infection, no vaccines are available to prevent hepatitis
List other non-hepatotrophic viruses that cause damage to the liver.
EBV CMV HIV, HHV6,7 Parvovirus HSV VZV
