Disease of the liver Flashcards
(102 cards)
1
Q
which cells does the Hep E virus effect
A
hepatocytes and Kupffer cells
2
Q
how is Hep C prevented
A
- blood donor screening - risk behaviour modification
2
Q
what is HBeAg
A
pre-core region protein of the C reading frame
3
Q
how long is Hep E secreted in the faeces before symptoms occur
A
2 weeks
4
Q
which Hep viruses can cause chronic infection
A
B, C and D
4
Q
explain immunity to Hep c
A
there isnt any there is no protective antibody response identified
5
Q
how do you diagnose acute viral hepatitis
A
- serological tests - ELISAs - test for IgM or IgG antibody to viral proteins - nucleic acid tests - PCR from blood/faeces
5
Q
complications of Hep A
A
- fulminant hepatitis - cholestatic hepatitis
5
Q
why is Hep A vaccine expensive to produce
A
- only grows in diploid cells (only has a limited number of generations) - needs to be tested that the vaccine is actually inactivated
5
Q
structure of the Hep E virus
A
- non-enveloped - icosahedral shape - +ve sense RNA
5
Q
incubation period of hep c
A
6-7 weeks (2-26)
6
Q
how can you tell the difference between acute and chronic serological response to hepatitis A
A
presence of IgG or IgM antibodies - IgM first - then wains - IgG later –> increases and then stays high
6
Q
how is Hep D prvented
A
- pre/post exposure immunization - risk behaviour modification
7
Q
incubation period of Hep A
A
average 30 days (15-50)
8
Q
what is the family name of the hepatitis A virs
A
Picornaviridae
10
Q
structure of the Hep A virus
A
- non-enveloped - outer protein capsid - +ve sense RNA
11
Q
Distribution of chronic Hep B virus worldwide
A
high prevalence in Asia and Africa
12
Q
vaccination for HBV also protects you against
A
HDV
13
Q
3 modes of transmission for hep B
A
Sexual parenteral (IDU, HCW) perinatal
14
Q
in which part of the hepatocyte does hepatitis replicate
A
in the cytoplasm (RNA virus)
15
Q
what is the life cycle of Hep A and Hep E viruses
A
transmitted from the bile and faeces into the environment –> contaminates food/water –> ingested –> replicates in intestinal epithelia –> viremia –> liver –> massive replication in the hepatocytes –> secreted into the bile duct –> faeces
16
Q
what is the most likely hepatitis virus that can be transmitted from sexual intercourse
A
Hep B
16
Q
for diagnosis what is HBeAG used for
A
indicates active replication of virus and therefore effectiveness of therapy
18
Q
what is the main acute viral hepatitis
A
hep A
19
at what time do the symptoms of Hep A appear
coincide with the emergence of the immune response against the virus
20
which specific gene SNP is associated with HCV recovery
IL28B C/C - predicts spontaneous clearance and sustained virological response
21
which areas of the world have the highest rates of Hep A
in countries with poorer sanitation - faecal oral spread more readily facilitated
21
how many times more prevalent is Hepatitis compared to HIV in Australia and in Victora
Australia - 18x Victoria - 16x
22
what is the gold standard for diagnosis of hepatitis
ELISA - only test that tells you about timing of the infection (change in antibodies)
22
Hep A prevention
- sanitation - immune globulin - inactivated vaccine
22
what is the family of the Hep E virus
hepeviridae family
23
what is the age relationship of getting chronic infection of hep b
- less than 5 --\> 30-90% change of having chronic infection - more than 5 --\> 2-10%
24
how is HBV vaccine made
now in yeast (used to be purified from blood and then inactivated)
25
what causes liver damage due to hepatitis
the immune response to the virus
26
treatment for Hep E
supportive therapy
28
how is the Hep A virus inactivated for the vaccine
with formalin
29
what proportion of children under 5 show jaundice when catching hep b
less than 10%
30
how is Hep B prevented
pre/post exposure immunisation
31
which virus is more common? Hep B or Hep C?
Hep C
33
treatment for Hep A
supportive rehydration and nutrition
34
which state in Australia has the highest rate of Hep A
northern territory - high prevalence in Indigenous communitees
34
what is the difference in serology between acute and chronic infections of hep b
acute - surface antigen level increases and then decreases to nothing chronic - surface antigen level increases and stays high. Also HBeAg stays high
35
structure of hep b
- outer envelope and inner capsid = double walled structure - dsDNA genome - incomplete double
36
how many vaccination doses are needed for Hep A
2-3
36
incubation time of hep b
average 60-90 days (45-180)
37
for diagnosis what is Anti-HBe Ig used for
to know that virus is no longer replicating (however the patient can still be positive for HBsAg which is made by integrated HBV)
39
What serological result tells you that you have acute hepatitis infection
- rising IgG titre - IgM antibody
40
what is the most common cause of liver cancer
chronic sequelae of hep b
41
what proportion of people present with jaundice when affected with hep c
20-30%
42
for diagnosis What is HBV-DNA used for
indicates active replication of the virus, more accurately than HBeAG - used mainly for monitoring response to thearpy
43
how do you get hepatocellular carcinoma from hep b
repeated hepatocyte destruction and regeneration leading to accumulations of chromosomal mutations (?possible role of HBV X-gene)
44
for diagnosis what is anti-HBs Ig used for
to document recovery and/or immunity to Hep B infection, but also successful vaccination
45
what is the response rate of giving IFN-alpha to HBV infected people
30-40%
47
how are Hep B, C and D transmitted
blood/blood-derived body fluids
49
what is your time window for giving immune globulin for Hep A
within 14 days getting the infection
50
replication cycle in the cell of Hep b
- enters the nucleus --\> RNA primer undergoes reverse transcriptase to allow complete circular DNA episome - makes pregenomic RNA by reverse transcriptase - can either go back on to the ER and bud off to become active infectious viral particles.. or - re-enter the nucleus to make more covalently closed circular DNA episome
51
how long do the symptoms last for Hep A
2-3 weeks (immune response dependent)
52
where does the hepatitis virus replicate
in the: - intestinal epithelium - hepatocytes
53
what is the increased probability if i have hep b that i will then go on to get hep c
100x more likely
54
when do you give IFN-alpha for HBV
for HBeAg +ve carries which chronic active hepatitis
56
what is the difference between Hep A and Hep E for prevention of getting the disease
immune serum globulin is NOT effective for Hep E
57
what is the treatment now for HCV in Australia
peg-IFNalpha + ribavirin + direct acting antibirals
58
structure of Hep D virus
delta antigen covering ssRNA - in turn, covered by HBsAg
59
what percentage of those infected with Hep C clear the virus completely at the acute stage of infection
30%
60
For diagnosis: what is HBsAG used as
a general marker of infection
61
for diagnosis what is anti-HBc IgM and IgG used for
anti-HBc IgM - marker of acute infection anti-HBc IgM - marker of chronic infection
63
what is the mainstay prevention for hepatitis A and E viruses
sanitation
63
what does hep B bring in with it
viral DNA polymerase short RNA primer 5' cap 2 short direct repeats
64
how many reading frames does the genome for hep b have? and what are they?
4 - C = core - S = surface - P = polymerase - X = immune evasion
65
what hepatitis virus is closely associated with IV drug users
Hep C
66
When can you get Hep D
only when you have been infected with Hep B previously or if you are coinfected with Hep B at the same time
67
what are the difference in outcomes between getting Hep D from coinfection with Hep B, or superinfection of Hep D when already previously infected with Hep B
coinfection --\> severe acute disease with low risk of chronic disease superinfection --\> usually develop chronic HDV disease and high risk of severe chronic liver disease
68
what is the treatment now for HCV in America
IFN-free DAA combination
70
case fatality of Hep E
- 1-2% overall - 15-25% in pregnant women
71
diagnosis of Hep E
- serology - ELISA - nucleic acid assays - immune electromicroscopy
72
what is the viral family of hep C
flavivirus
74
explanation of age-related outcomes of hepatitis
exposure in early life results in less severe acute disease due to less T cell response, but higher rates of chronic infection
75
which hepatitis virus is the major cause of liver transplant
Hep C
77
symptoms of Hep A
- jaundice - vomiting - pale faeces - dark urine
79
which hepatitis viruses can be passed to the infant during childbirth with medication
Hep B
80
what is the serology marker of the presence of infectious virus
HbeAg
81
what proportion of people get chronic hepatitis from hep c
70%
82
incubation period of Hep E
~40 days (2-10 weeks)
84
high, medium and low concentrations of Hep b virus in various body fluids
high: blood, serum and wound exudates medium: semen, vaginal fluid, saliva low/not detectable: urine, faeces, sweat, tears, breastmilk
85
current antiviral drugs used in Australia for HBV
- IFN-alpha - nucleoside and nucleotide analogues
86
explain the genome of Hep c
ss linear RNA
87
what is the most likely hepatitis virus that can be transmitted from IV drug using
HEP C then Hep B
88
which hepatitis viruses do NOT have chronic sequelae
Hep A and E
89
replication of hep b, c and D in the body
- replication in the liver - viremia --\> blood, semen and secretions - sex/close contact - penetration of mucosal epithelium (not replication) - blood (viremia) - replication in the liver
90
which facts about Hep A makes it fabulous to make a vaccination against it?
- there is only a single serotype worldwide - replicates in cell culture
91
what is the difference between the acute and chronic serological responses to hep A and E viruses
Hep A - IgG increases and then stays high Hep E - IgG increases and then decreases.. but still higher than IgM Ab
92
which hepatitis viruses can be passed to the infant during childbirth with no medication
Hep B!! little Hep C
93
what proportion of people over the age of 5 show jaundice as an acute sign of catching hep b
30-50%
94
adult symptoms and signs of Hep E
- jaundice - malaise - anorexia - abdominal pain - hepatosplenomegaly - nausea and vomiting - fever - pruritus
95
describe the structure of hep c virus
- 2 envelope proteins - lipid envelope - ss RNA genome inside nucleocapsid core
96
what is the surface antigen for hep B
HbsAg
97
what is the chance if you have hep b that you will go on to get hepatocellular carcinoma
2-10%
98
what causes jaundice
hyperbilirubinaemia
99
describe the organisation of the hep C genome
translated as 1 long polypeptide that is then cleaved into smaller peptides that are either structural or non-structural
100
most outbreaks of Hep E are related to...
faecally contaminated drinking water
101
which hepatitis viruses are transmitted by the faecal-oral route
A and E
102
what is the progression of hep b
acute infection --\> chronic hepatitis --\> cirrhosis --\> liver cancer
