Term
Common features of Viral Hepatitis |
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Definition
- Upper right quadrant ab. pain, nausea, anorexia, fatigue, fever
- Jaundice, hepatomegaly
- Elevated: liver enzymes, bilirubin in blood and urin, Alkaline phosphatase, LDH
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Term
Hepatitis A Virus (HAV): General |
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Definition
- Picornaviridae, Enterovirus group
- (+)ssRNA virus
- very stable in environment
- causes acute or asymptomatic infection
- "infectious hepatitis"
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Term
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Definition
- Fecal/oral due to crowding and poor hygiene
- community outbreaks
- assymptomatic = source of new infections
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Term
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Definition
Incubation period: avg = 30 days
Jaundice:
- >14 yrs 70-80%
- 6 - 14 yrs 40%-50%
Complications: Fulminant hepatitis, cholestatic hepatitis
Typical disease: acute for weeks
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Term
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Definition
enters intestinal tract -> blood -> liver -> replicates in hepatocytes -> liver damge from virus and immune response -> leaves liver via bile duct -> shed in feces |
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Term
Diagnosis of HAV infection: |
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Definition
Definitive diagnosis of acute infection:
α-HAV IgM in serum
Definitive diagnosis of past infection:
α-HAV IgG |
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Term
Hepatitis B Virus (HBV): General |
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Definition
- Hepadnaviridae family
- enveloped, dsDNA
- replicates via RNA intermediate
- heat and pH resistant
- humans are only reservoir
- acute and chronic infections
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Term
HBV: outcomes of infections |
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Definition
- 90% acute infections
- Chronic persistent (asymptomatic)
- Chronic active (symptomatic)
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Term
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Definition
Incubation period: avg = 100 days
Jaundice: >5 yrs 30-50%
Chonic infection: more likely in children <5 yrs
Acute infection more likely in adults
15-25% die of chronic liver disease |
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Term
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Definition
entry via blood or semen -> travel to liver -> replication in liver (100days) -> liver damage due to immune response (not virus) |
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Term
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Definition
general marker of HBV infection |
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Term
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Definition
recovery and/or immunity to HBV infection |
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Term
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Definition
marker of acute infection |
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Term
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Definition
past or chronic infection |
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Term
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Definition
active replication of virus and infectiveness |
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Term
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Definition
virus no longer replicating |
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Term
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Definition
active replication of virus
-more accurate than HBeAg |
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Term
List the expected serological findings in an acute HBV infection |
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Definition
HBsAg +
HBeAg +/-
α-HBcAg IgM +
α-HBcag IgG + right after infection; - rest of the time |
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Term
List the expected serological findings following recovery of and acute HBV infection |
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Definition
HBsAg -
HBeAg -
α-HBsAg +
α-HBcAg IgM -
α-HBcAg IgG (total) + |
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Term
List the expected serological findings in a chronic persistent HBV infection |
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Definition
HBsAg +
HBeAg -
α-HBcAg IgM -
α-HBcAg IgG (total) +
α-HBeAg +
DNA polymerase - |
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Term
List the expected serological findings in a chronic active HBV infection |
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Definition
HBsAg +
HBeAg +
α-HBcAg IgM -
α-HBcAg IgG (total) +
DNA polymerase + |
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Term
Hepatitis D (delta) Virus (HDV): general |
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Definition
- ssRNA, unclassified virus
- contains HDV Ag derived from HDV
- contains HBsAg derived from HBV
- needs HBV as helper to code its surface protein
- aquired as coinfection or superinfection of HBV
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Term
HDV: transmission and risk group |
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Definition
- percutaneous exposures
- permucosal exposures
- Intravenous drug users and their partners
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Term
HDV: clinical features of coinfection |
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Definition
severe acute disease - mostly adults
low risk for chronic infection
serology will show α-HBs in later weeks
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Term
HDV: clinical features of superinfection |
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Definition
usually from contracting HDV while person already has a chronic HBV infection
-high risk of severe chronic liver disease (chronic active or fulminant hepatitis)
serology: will continually have HDV-RNA, HBsAg, α-HDV IgM; will not have α-HBs |
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Term
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Definition
acute
high titers in chronic during times of reactivation |
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Term
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Definition
acute or chronic HDV infection |
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Term
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Definition
declines late in acute, high titers in chronic |
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Term
Hepatitis E Virus (HEV): general |
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Definition
- a NANB hepatitis virus
- non enveloped, (+)RNA
- related to calicivirus
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Term
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Definition
- fecal/oral
- acute sporadic outbreaks
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Term
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Definition
Incubation: avg 40 days
Case-fatality rate: pregnant 15 - 25%
severity increases with age |
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Term
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Definition
Flavivirus; (+)ssRNA
mild acute hepatitis that usually becomes chronic persistent
can be found in coinfections with HC, HBV and HIV |
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Term
Hepatitis C Virus (HCV): General |
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Definition
- Flavivirus; (+)ssRNA
- accounts for 90% of NANBH infections
- reservoirs = humans and chimpanzees
- causes chronic infections
- undergoes rapid antigenic variation in infected individuals
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Term
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Definition
percutaneous route
- injecting drugs
- needle stick injuries
- formerly blood transfusion (pre 1990)
permucosal |
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Term
Clinical features of HCV infection |
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Definition
Incubation: avg 8 - 9 weeks
Jaundice: <25%
chronic infection: 70 - 85%
chronic hepatitis: 60 - 70 %
cirrhosis 5 - 20% (takes 10 - 20 yrs of infection) |
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Term
Factors that promote progression of chronic HCV infection |
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Definition
- increased alcohol intake
- age >40 yrs at time of infection
- HIV co-infection
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Term
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Definition
- test for presence of anti-HCV
- if positive, confirm with RIBA test
- Qualitative (yes/no) and Quantitative (viral load) PCR tests
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