Hepatitis (Exam 2) Flashcards
Hepatitis
Inflammation of the liver
Two types of hepatitis
Acute (<6 months)
chronic (>6 months)
Causes of Hepatitis
VIRUSES
drug toxicity
alcohol
autoimmune diseases
bacteria
parasites
Symptoms of Hepatitis
Swelling of liver
Jaundice
dark urine
Transaminase- alkaline phosphate levels increased
Symptoms of Viral Hepatitis
Yellowing skin and eyes, dark urine, loss of appetite, fatigue
Compensated Cirrhosis
Liver can still function, no signs or symptoms
Decompensated Cirrhosis
Liver is too damaged to function normally, symptoms such as jaundice and ascites are present
Progression of Hepatitis
Normal liver –> chronic hepatitis –> hepatitis with fibrosis –> bridging fibrosis –> cirrhosis with hepatocellular carcinoma
Which hepatitis have a vaccine?
Hepatitis A and B
No vaccine for Hepatitis C (good luck)
Which hepatitis cause liver cancer?
Hepatitis B and C
How long does Hepatitis A last?
Few weeks to several months (2 months), most recover with no lasting liver damage, very rare but death can occur
How long does Hepatitis B last?
Few weeks to serious, life-long condition with individuals developing chronic liver disease - cirrhosis, failure, cancer
How long does Hepatitis C last?
Few weeks to serious, life-long condition
Most develop chronic hepatitis C
5%-25% with ^ will develop cirrhosis over 10-20 years
Unimmunized infants who get infected by hepatitis B
Develop chronic INFECTION
Older children and adults who get infected by hepatitis B
Develop chronic hepatitis B
How is Hepatitis A spread?
Ingesting fecal matter from contaminated sources/people
Food, drinks including ice, blood, stool, direct sex contact, poor sanitation
How is Hepatitis B spread?
Blood, semen, bodily fluids from infected person enter body of uninfected, sex, sharing of personal items, needles. can also be transmitted from birth to an infected mother
How is Hepatitis C spread?
Blood from infected person enters body of someone uninfected
Global mortality from viral hepatitis is…
INCREASING o_o
HAV virus
ssRNA
No envelope - Capsid
Picorna/hepatovirus
Fecal-oral
Not chronic
heat and acid stable
high prevalance/contagious
HBV virus
dsDNA
Envelope
Hepadnaviridae
Parenteral
Chronic
HCV virus
ssRNA
Envelope
Parenteral
Flaviviridae + Hepacivirus
Chronic
HDV virus
ssRNA
Envelope
Parenteral
Delta virus
HEV virus
ssRNA
No envelope - Capsid
Waterborne, animals
Togavirus and alpha virus-like
Chronic - immunocompromised
who is at risk for HAV?
close contacts of HAV-infected individuals, recreational drug users, travelers to endemic areas, homeless individuals, MSM
prevention of HAV
vaccination - HepA (inactivated/killed vaccine)
post-exposure prophylaxis within 14 days - immune globulin
HAV pathogenesis
ingestion
replication in oropharynx/GI tract
transported to liver
sited in bile
transported to intestines
shed in feces
brief viremia
cellular immune response-clinical disease and control
uses liver cell for viral replication; interferes with liver function
major site of replication
liver
incubation of HAV
15-45 days
incubation of HBV
45-160 days
incubation of HCV
15-150 days
incubation of HDV
30-60 days
incubation of HEV
15-60
leading cause of liver cancer worldwide from which infection?
Hepatitis B infection
- no cure, infants and children most likely to develop this
- vaccine preventable
HBeAg
HBV e-antigen (expressed when actively replicating)
HBsAg
HBV surface antigen
HBcAg
HBV core antigen
HBV care for adults and children
see liver specialist every 6 months.
- physical exam
- blood tests for Hep B markes
- blood tests for liver enzymes (ALT/AST)
- blood tests for liver cancer screening (AFP)
- imaging studies of the liver (ultrasound, CT scans, FibroScan)
HBV treatments
direct anti0viral medications (nucleoside analogs):
- Entecavir
- Lamivudine
- Adefovir dipivoxil
- Telbivudine
- Tenofovir alafenamide
-Tenofovir
Immune boosters:
- interferon alpha 2b
pegylated interferon
who is at risk for Hepatitis A?
close contacts of HAV infected
recreational drug users
travelers
homeless individuals
MSM
Does HAV cause chronic infections?
NO!
infection usually resolves within 2 months
HAV is preventable by
vaccination and post exposure prophylaxis
HAV pathogenesis
ingestion –> replication in GI tract –> transported to liver –> shed in bile –> transported to intestines –> shed in feces
prevention of HAV preexposure? post exposure?
pre - HepA vaccine (inactivated/killed vaccine)
post - immune globulin (within 14 days)
what part of the virus is used for vaccine?
the surface antigen
HBV viral genome
3.2 kb
core and surface antigens
Hepadnaviral replication
RC-DNA transported to nucleus –> repaired to form cccDNA –> transcription to pgRNA –> pgRNA is encapsidated and reverse transcribed in nucleocapsid
Hepatitis B infection is the
leading cause of liver cancer worldwide
is there a cure for hepatitis B?
no :(
how is hepatitis B transmitted?
parenteral via infected body fluids
unprotected sex
needle sticks
mother to fetus
global viral hepatitis B
257m global
acute hepB serology
total anti-HBc stays for a long time
IgM anti-HBc goes down
chronic hepB serology
HBsAg stays around for some time and is larger than total anti-HBc (antibodies)
standard recommendation for care to visit a liver specialist is
every six months
can be more/less depending on medical situation
testing during liver specialist recommendation
physical exam
blood tests for hepb markers
blood tests for liver enzymes
blood tests for liver cancer screening
imaging studies of the liver
persons who are HBsAg positive should not
not share toothbrushes/razors
not share injection equipment
not share glucose testing equipment
persons who are HBsAg positive should have
household and sexual contacts vaccinated
so blood doesn’t spread, persons who are HBsAg positive should
cover open cuts and scratches
clean blood spills with bleach solution
not donate blood, organs or sperm
subunit recombinat vaccine
first dose given at birth
HEV is transmitted via
fecal oral route, principally via contaminated water
what happens if someone is infected with hep B at birth?
progress to chronic HBV infections
is there a vaccine for HEV?
yes but it is not approved in the US
only in China
Treatment for HEV
Ribavirin
treatment of severe acute HEV and chronic HEV infections
symptomatic treatment
HEV infections usually
resolve on their own within 4 to 6 weeks
blood donor screening is done for which hepatitis?
hepB and hepC
Hepb treatment
interferon (PegIFN)
the cure rates for chronic HCV
rising
progression of hepatitis C can take
25-30 years
serologic pattern of acute HCV infection
anti-HCV is still present even if the virus isn’t
might not have active virus over time
HBV post exposure prophylaxis
anyone who is non-HBV-immune of unknown HBV status should receive prophylaxis and initiation of HBV vaccination WITHIN 24 HOURS of suspected exposure
prevalence by risk based of HCV is
MSM
long term kidney dialysis
healthcare workers exposed
children born to HCV infected mothers
incarceration
recipient of a unsterile tattoo
recipients of blood transfusion
In the United States, Hepatitis C is
under diagnosed (75%)
how much of the world has viral hepatitis C
71m global (1/4 of the amount of hepB)
chronic infection of HCV can lead to cirrhosis which leads to
liver failure or hepatocellular carcinoma
North America is not really affected by hepC because of
screening in blood banks
Hepatitis C virus is associated with
flavivirus (dengue, west nile, yellow fever, zika)
heterogeneity of HCV
no proofreading in the polymerase –> mutations –> viral diversity
HDV is a
defective virus that consists of a protein capsule surrounding low molecular weight RNA
heterogeneity of HCV allows for
escape from host immune system and medications
how many genotypes and subtypes of HCV are there?
six major genotypes with over 15 subtypes
there are multiple different types of hepC that differ
slightly in the genome
HCV life cycle follows
APUMAR
HBV-HDV
co-infection
getting infected simultaneously with HBV and HDV
low risk 5% of chronic infection, severe acute disease
HDV superinfection in HBV Carrier
being chronically infected with HBV and contracting HDV
usually develop chronic HDV infection
high 70-90% chronic liver disease
HDV therpahy
none, sucks to be u
Lambda mechanism
immune response stimulator
Myrcludex B mechanism
entry inhibitor
Lonafarnib mechanism
prenylation inhibitor
ezetimibe
NTCP inhibitor
REP 2139
REP 2165
HBsAg Inhibitor
GI- 18000
Immune response stimulator
ALN-HDV
RNAi Gene Silencer
