Viral GI I Flashcards
What is the color of the stool in hepatitis? Urine color?
Gray stool (acholic)
Dark urine
What is hepatitis?
Liver inflammation
What are the three types of hepatitis?
- Acute
- Chronic
- Filminant
What is the prodrome of hepatitis? When do these present?
HA, myalgias, arthralias, n/v mild fever 1-2 weeks prior
What causes the gray stool of hepatitis (acholic stool)?
Loss of heme in it
What causes the jaundice and scleral icterus caused by acute hepatitis?
Increased bilirubin
Why is there an increase bili in hepatitis?
Lower liver conjugation of bili from biliverdin
What are the levels of bili in hepatitis jaundice?
> 3 ml/dl
commonly 5- 20 ml/dL
What is bilirubin in urine indicative of?
Liver disease
What are the LFTs that are elevated in viral hepatitis?
ALT
AST
Which has higher LFTs, viral or other causes of hepatitis?
Viral
What is chronic viral hepatitis?
Hepatitis that does not resolve within 6 months
What is the problem with chronic hepatitis (what does it cause)?
Predisposes individual to hepatocellular carcinoma and/or cirrhosis
How long does hepatocellular carcinoma take to develop in chronic viral hepatitis?
15-40 years
What is the cause of developing cirrhosis of the liver in hepatitis?
Immune response
What causes the liver CA in chronic viral hepatitis?
Constant regrowth of hepatocytes after damage
Will breast CA that metastasizes to the liver function the same way to cause liver CA as hepatocellular carcinoma caused by hepatitis?
No
What happens to the liver between chronic hepatitis and the development of HCC?
Cirrhosis
What is the most severe form of viral hepatitis?
Fulminant hep
What happens in fulminant hep?
Rapid, severe necrotic hepatitis that can lead to encephalopathy
What are the complications of fulminant viral hepatitis?
Cerebral edema Brainstem compression GI bleeding Sepsis Organ failure
How can you help someone with fulminant Hep?
Liver transplant
What are the five types of hepatitis?
A - E
What are the two hepatitis viruses that are transmitted through the fecal-oral route?
A and E
What are the three hepatitis viruses that can cause chronic hep infections?
B- D
Is there a vaccine for hep A?
Yes
What are the symptoms of hep A? How long do these usually last?
Abdominal pain, n/v/d
> 2 months
How do you diagnose acute hep A infx?
IgM antibodies for HAV
What family of viruses is hep A from? genome type?
Picornavirus
+ ssRNA
Are children usually symptomatic with Hep a infx?
No
Does hep A cause chronic hep? Fulminant?
No chronic,
Fulminant, rarely
What is the antibody seen in acute hep a infx? What antibody provides long term immunity?
IgM for acute
IgG for immune
How is the Hepatitis vaccine given? How many times?
IM x2
What is the age range for Hepatitis A vaccine?
12-23 mo
What is the post-exposure prophylaxis for hep A? When is this used?
Preformed anti-HAV IgG and vaccine
Used in high risk populations
What is the prevalence of Hep a in the US?
about a 1/3 infected
What is the prevalence of Hep B in the US?
5%
What do complete virion particles of Hep B look like under the scanning EM? What are they called?
Circle called Dane particles
What are the tubes and spheres that are seen around complete Hep B molecules in a scanning EM?
incomplete, noninfectious forms of Hep B
What is the family of Hep B? Genome?
Hepadnavirus family
dsDNA
What enzyme is needed for Hep B to replicated, and serves as a drug target?
Reverse transcriptase
What is the surface antigen for Hep B? Is this soluble? What is this seen on (dane particles or tubules?
HBsAg
Soluble
Seen in both tubules and dane particles
What is the core antigen for Hep B? Is this soluble/detected in the serum?
HBcAg
Not soluble, therefore not detected in the serum (antibodies are though)
What is the Hep B antigen associated with DNA? Is this soluble/found in serum?
HBeAg
Soluble, thus found in serum
How long does HBsAg last in acute vs chronic infections?
Acute = peaks and disappears
Chronic, stays high
How long does HBsAg antibody last in acute vs chronic infections?
Acute = peaks after HBsAg peak
Chronic, stays high
How long does ALT stay elevated in chronic vs acute HBV?
Acute = short time
Chronic = throughout infx
What is the mode of transmission for Hep B?
Sexual transmission or perinatal
What percent of HBV infections result in chronic infections? What is this correlated with?
5%, decreasing with age
How many adults are asymptomatic with Hep B?
50%
The younger you are the (blank) likely you are of developing a chronic Hep B infx?
The younger you are the MORE likely you are of developing a chronic Hep B infx?
What is the treatment for acute infx of Hep B? Chronic?
Acute = none
Chronic = Lamivudine or famcyclovir/adefovir
What is the MOA of lamivudine that treats Hep B?
Reverse transcriptase inhibitor
What is the MOA of famcyclovir/adefovir nucloside for Hep B?
Nucloside inhibitor
What is the vaccine for Hep B made of?
Recombinant HBV vaccine produced in yeast
When is the Hep B vaccine given?
Soon after delivery, but 3 total doses
What are the three tests that can be performed to diagnose Hep B on blood donations?
Surface antigen
B core antibody
ALT
What is the prevalence of Hep C in the US?
2% infected
Does Hep C cause chronic hepatitis?
yes
Does Hep B cause chronic hepatitis? D?
Yes
Does Hep A cause chronic hep? E?
No
What is the family that Hep C belongs to? Enveloped? Genome?
Flavivirus
Enveloped
+ssRNA
How is Hep C usually transmitted?
Injection drug use
How do you screen for Hep C?
Antibody based test for Anti HCV antibodies
How do you confirm Hep C?
Nucleic acid based tests for detection of the viral genome
Are the acute symptoms of Hep C more severe or milder than A and B?
Milder
What is the chance that Hep C develops into chronic infx?
70%
What is the MOA of Sofosbuvir (treatment for Hep C)?
RNA dependent RNA polymerase inhibitor
What is the main viral drug that treats Hep C? What does this depend on?
Sofobuvir, but depends on the genotype of Hep C
Is there a vaccine available for Hep C?
No
How can you prevent Hep C infx?
Reduce IV drug use
Protected sex
Screen blood supply
What is the test for Hep C (what is it looking for)?
Looking for Hep C anti-HCV
What is the morphology and genome type of Hep D?
small, circular ssRNA
What does Hep D need to survive?
Needs Hep B virus to place surface antigens
What is the exterior surface of Hep D? What is the consequence of this?
Hep B surface antigen
Means that this can only infect cells that have Hep B antigen on cell surface
Who is at risk of Hep D?
People who have been previously infected of Hep B or are currently
What is the only Hep virus that directly damages that liver?
Hep D
How do you diagnose Hep D?
ELISA
What is the treatment for Hep D?
No specific antiviral treatment
How do you prevent Hep D infx?
Vaccinate against Hep B
What is the Hep E virus family? Genome?
Hepevirus
+ssRNA
What is the route of transmission for Hep E?
Fecal-oral route
Who is usually infected with Hep E?
Travelers
Who is at high risk of death from Hep E?
Pregnant women
Is there a vaccine for Hep E?
No
What is the treatment for Hep E?
Supportive
What is the virus family for Hep D?
Deltavirus
What is the virus family for Hep B?
Hepadnavirus
How long does it take for Hep A to resolve?
2 months
What percent of neonates born to HBV + mothers get chronic HBV?
90%
What is the chance that HBV will develop into hepatitis (note, NOT chronic; fulminant)
1-2%
True or false: Detecting HBsAg in the blood means that there is an acute or chronic infection aking place
True
Anti-HBcAg
antibodies are used as a marker of what?
a current or
previous infection with HBV
Are anti-HBcAg
IgM antibodies detected in acute or chronically infected patients? Are these observed in immunize people?
Acute (will switch to IgG)
Not in immunized people
What is the treatment for acute HBV infx?
Supportive
When is the first dose of Hep B vaccine given?
Prior to hospital discharge
What does the Hep B vaccine contain?
Recombinant protein from Hep B
Premature infants born to mothers of unknown or positive HBsAg status should receive the vaccine and HBIG within how many hours of birth?
12 hours
For how long does the HbeAg antigen last in an acute and chronic Hep B infx? What happens after this disappears?
Only for acute phase, then turns to antibody for it
[NOTE that it lasts longer in chronic, but still goes away after some time]
Can you see HBV DNA in acute infx?
No, just chronic
When is the antibody for HBV core antigen produced in acute vs chronic infections?
Acute comes on after HBsAg disappears
Chronic, always there
For an acute infection with HBV, which of the four antigens/antibodies will you detect? (give answer in numbers)
- HBsAg
- antiHBsAG
- total antiHBc IgM
- antiHBc IgM)
1, 3, 4
For a chronic infection with HBV, which of the four antigens/antibodies will you detect? (give answer in numbers)
- HBsAg
- antiHBsAG
- total antiHBc IgM
- antiHBc IgM)
1, 3
For vaccination against HBV, which of the four antigens/antibodies will you detect? (give answer in numbers)
- HBsAg
- antiHBsAG
- total antiHBc IgM
- antiHBc IgM)
2
For a previous infection with HBV, which of the four antigens/antibodies will you detect? (give answer in numbers)
- HBsAg
- antiHBsAG
- total antiHBc IgM
- antiHBc IgM)
2, 3
For a person susceptible to HBV, which of the four antigens/antibodies will you detect? (give answer in numbers)
- HBsAg
- antiHBsAG
- total antiHBc IgM
- antiHBc IgM)
None
What type of hepatitis infection is more likely to occur with coinfection of Hep B and D?
Fulminant
Hep D infection is considered a what type of infection?
Superinfection
Which immune cell specifically, causes liver damage in hepatitis?
CTLs
What is the “window period” of acute hepatitis B?
Time between HBsAg in the serum, and its antibody
What is the difference between chronic replicative hep B and chronic non-replicative?
Replicative = HBeAg is present
Non-replicative = not present
[recall that e is for the DNA component of Hep B]
What percent of adults who contract HBV will progress to a chronic infection? How about for neonates?
10% for adults
90% for neonates
If all you see in a hep infection is antibody, is the pt still infected?
No
Why is a superinfection with Hep D and Hep worse than coinfection?
Already has Hep B surface antigen