Hepatitis Flashcards
Features of HAV (4)
RNA virus
foecal-oral route
endemic in S. America/Africa
incubation of 2-6wks
Sx of HAV infection (5)
fever, malaise
arthralgia
anorexia, nausea
jaundice, hepatosplenomegaly, enlarged LNs
loss of taste for cigarettes
Tests for hep A (3)
AST and ALT rise 22-40d after exposure
IgM is raised acutely. Occurs after 4wks with jaundice.
IgG raised for life. Occurs after 6wks.
Rx and prognosis of hep A
supportive
no chronic carrier status
Vaccination for hep A
provides immunity for 1yr.
give to:
- those w. hep B/C who are not immune as superimposed hep A infection>very severe acute hepatitis
- MSM
- sewage workers
- IVDU
- travelers
Features of HBV (5)
DNA virus
most people don’t become chronic carriers:
- infection in life>5% chance of chronicity
- infection in utero/1st 2-3yrs>90% chance of chronicity
incubation of 1-6mo
spread by blood, sex, vertically, direct contact
liver damage is immune-mediated
Prevention of vertical transmission of Hep B (3)
vaccinate baby at birth
maternal IVIg if HBeAg+ve
maternal antivirals e.g. tenofivir during 3rd timester if viral load high.
Sx of Hep B infection (3)
prodrome of malaise, anorexia and arthritis
Other Sx similar to hep A w. more pronounced arthralgia:
- arthralgia
- nausea, anorexia
- jaundice, hepatosplenomegaly, swollen LNs
- loss of taste for cigarettes
Hep B serology (3)
HBsAg:
- present 1-6mo after exposure
- if persists=carrier status
- if only anti-HBsAg antibodies are present, this implies vaccination.
HBeAg:
- implies high infectivity
- present in acute, active illness
- secreted by virus itself
- anti-HBeAg implies lower infectivity
HBcAg:
- IgM=acute infection
- IgG raised lifelong, implies past infection
Hep B carriers (4)
chronic carriers have HBsAg for >6mo
virus can be cleared but most become lifelong carriers
carriers can develop liver disease, cirrhosis and HCC
can also develop extra-hepatic disease e.g. membranous GN and polyarteritis nodosa.
Rx of hep B (3)
Rx as outpatient, monitor LFTs and coagulation closely
all with chronic liver inflammataion>antivirals:
- PEG-IFN
- nucleoside anaologues e.g. tenofovir
- aim to seroconvert to anti-e
- aim to prevent cirrhosis and HCC
Hep B prophylaxis (2)
primary prophylaxis; preventing infection: vaccination after exposure
secondary prophylaxis; preventing recurrence: Ig
Hep B vaccination and screening (3)
3 doses of vaccination+ booster at 5yrs. must test 12wks after last dose
vaccine offered to those at high risk e.g. IVDUs, sex workers, healthcare workers
screening for pregnant women, those w. potential exposure, and those with RFs e.g. HIV, immunosuppression etc.
Disease course in Hep C (3)
acute phase is mild:
-anorexia, lethargy
85%>silent chronic carriers
20%>develop cirrhosis in 20yrs of which 4% develop HCC
can trigger:
- autoimmune hepatitis
- porphyria cutanea tarda
- mixed essential cryoglobulinaemia
Tests for Hep C (4)
LFTs
serology
- can take up to 1mo to seroconvert therefore only useful for diagnosis chronic not acute infection
- HCV RNA PCR can be used to detect acute infection.
liver biopsy to assess damage
assess genotype