Viral Hepatitis Flashcards
Besdies the hepatitis viruses, what other viruses can cause hepatitis?
CMV
EBB
HSV
Parvovirus B19
Describe the presentation of Hep A?
aself limited illness with jaundice, fatigue, fever, anorexia, diarrhea, dark urine, pale stools, abdominal pain
How is the spread of Hep A?
fecal-oral
How long is the incubation for Hep A?
15-50 days
2-6 wks
Why has Hep A incidence declined since the 1990s?
a vaccine became available
only 1200 cases in the US in 2014
What are the appropriate serologic tests for HAV?
Total Anti-HAV antibody (indicates acute, previous infections or immunization)
IgM Anti-HAV (indicates acute infection)
Who shoul dbe vaccinated for hep A?
all kids at 1 yo
kids 2-18 yo where routien vacc is implemented
travelers to high prevalence areas
Men who sleep with men
high risk: drug users, occupational exposures
chronic liver disease patients
patients receiving clotting factors
What percentage of the 3-4 million people in the US with hep C are diagnosis?
only 25-50%
What is the rate of chronic hep C infection?
75-85%
What is the rate of chronic liver DISEASE?
60-70%
What is the rate of cirrhosis in the next 20-30 yrs?
5-20%
When can you start to detect viral hep C RNA in the blood?
1-3 weeks post exposure
When can you start to detect hep C antibodies?
can take 20-150 days before you can see the antibodies
Who’s more likely to clear the hep C virus - people who get acutely sick or people who are asymptomatic?
symptomatic patients more likely to seroconvert
so you want to get sick
What are the HCV modes of transmission?
percutaneous exposure to infected blood
sexual transmission (less common)
mother to child (4% risk of trans in preg/labor)
What are the lab test options for HCV?
- screening with EIA/CIA
- Molecular assays (quantitative and genotyping)
- liver biopsy not usually needed
Positive antibody screens for HCV should be confirmed by what? Unless?
usually RNA detection
unless their titer is super high, then you can just go on th eone test
What are the ost common genotypes of HCV in the US?
1a and 1b
2 and 3 less common
What are some reasons for false negative results?
immunosuppression
low levels of anti-HCV Ab
Absence of antibodies against antigens in the test (if they’re directed at a different part of the virus than the test is looking for)
testing in the “window period” - before 11 wks
Is it possible using the antibody screening test for HCV to determine acute, chronic or resolved infection?
no
that’s why you look for the RNA confirmation - is there actually virus in the patient’s blood?
Who should be screened for He pC?
- people born between 1945-1965 (baby boomers)
- hx of IVDU
- Recipients of clotting factor concentrates made before 1987
- recipients of blood transfusions/solid organ transplants before 1992
- Patient who have ever received long-term hemodialysis treatment
- known exposure
- w/ HIV
- kids with HCV moms
What is the goal for treatment HCV?
sustained virologic response (indetectable viral RNA 24 wks after therapy completed) - basically cure now
Is hep B a DNA or RNA virus?
DNA
How does age of infection with HBV affect severity and chronicity?
younger, more likely to go on to chronic
older - more likely to be acutely sicker
Who should be vaccinated for HBV?
everyone udner 18
everyone over 18 with increased risk
What kind of vaccine is used for HBV now?
recombinant form of hBsAg
WHat’s the transmission for Hep B?
contact with infected blood or mucosal membranes (sex, IVDU,sick mom, needle sticks, etc)
What is the incubation for hep B?
60-150 days
2-6 mp
What is the first serologic marker for HBV to appear?
HBsAg
surface antigen
WHen does surface antigen disappear?
1-3 months after the ajundice (when you get anti-HBs)
if it doesn’t clear = chronic infection
Does the Anti-HBs go away eventually?
nope - persists indefinitely
also will be positive in immunized persons
WHen is Anti-HBc (core antibody) positive?
during the window when surface antigen is declining and surface antibody is appearing
can persist for years
WHen does envelop antigen appear?
with surface antigen
What does envelope antigen indicate?
presence of intact virions, = means it’s actively replicating and dividing
surface antigen negative
anti core negative
anti surface negative
never been exposed, non-vaccinated
sufact antigen negative
anti-core neg or positive
anti-surface positive?
seroconversion
so either resolved (positive anti core) infection or vaccinated (negative anti-core)
surface antigen neg
anti-core positive
anti-surface negative
window period! patient IS infected, but it looks favorable because they’re clearing surface antigen
Surface antigen positive
anti-core igM positive
anti-surface negative
acute hepatitis infection
surface antigen positive
anti-core IgM neg, IgG positive
Anti-surface negative
chronic infection (IgG anti-core and no anti-surface)
How is hepatitis D transmitted?
percutaneous exposure
What kind of virus is hep D?
defective RA virus
Hep D needs to be a coinfection with what?
hep B
What is the difference between co-infection and superinfection
co-infection isyou get with B and D at the same time
superinfection is when chronic HBV carriers get D later
Which one has worse acute disease - co-infection or superinfection?
co-infection, but less will go on to develop chronic infection
How can you test for HDV?
you dan do an assay for total anti-delta or just IgM for acute infection
also can do a molecular analysis to detect RNA
Where is Hep E located globally
asia
india
middle east
mexico
WHat is the indubation period for hep e?
2-8 wks (similar to A)
Who have a high mortality with hep e?
pregnant women (up to a third will die!)
otherwise it’s usually a self-limited disease
What is hep G?
an RNA virus transmitted by blood, maybe causes mild disease. not a significant health problem
Bsaic workup for acute viral hepatitis will include what?
IgM anti-HAV IBsAg IgM Anti-HBc anti-HCV anti-HDV (if fulminant disease, or known HBV)
Can a negative anti-HCV exclude acute infection?
nope - there’s a window period
What is the basic panel for chronic hepatitis testing?
HBsAg (if positive, do HbeAg and anti-HDV)
Anti-HCV (if positive, do RNA PCR)
What are some nonviral etiologies of chronic hepatitis?
chemical injury, drugs, alcohol autoimmune hepatitis hemochromatosis alpha1 anti trypsin def wilson's
