Viral hepatitis Flashcards
What is viral hepatitis?
RNA virus
How is Hep A spread?
Epidemiology?
Faeco-oral or shell fish
Common infection
Endemic in south America and Africa
Common in children
Clinical presentation of hep A
Incubation = 2-6wks
Acute hepatitis only- no chronic disease.
Fever
Malaise
Anorexia
Nausea
Arthralgia
THEN: Hepatospenomegaly, Jaundice, Lymphadenopathy
100% immunity after infection
Tests for hep A?
AST and ALT rise 22 to 40 days after exposure
IgM detection shows it is a recent infection
IgG is detectable for life
Treatment for hep A
Supportive Rarely developes to fulminant hepatitis. If so interferon A Active immunisation (vaccination for travellers) with an inactivated protein derived from HAV
What is fulminant hepatic failure (acute liver failure) ??
Rapid development of acute liver injury
with severe impairment of synthetic function and hepatic encephalopathy in a patient without obvious previous liver disease
What is hepatitis B
DNA virus
How is hep B spread
Blood products, IVDU, sexual and direct contact
Very infectious
Epidemiology of hep B
Endemic in – Far East, Africa, Mediterranean
Clinical presentation of hep B
Incubation= 1-6 months
Resemble hepatitis A
Arthralgia and urticaria are more common
Chronic Hep B causes Hepatitis
Diagnostic tests and results for hep B?
HB surface antigen persists over 6 months–> carrier status
HB core antigen only present for 1.5 months after acute illness
Biopsy indicated unless ALT normal
Vaccination – passive immunisation given to non-immune contacts after high-risk exposure
Aim of Hep B treatment is to clear HBsAg and prevent cirrhosis and hepatocellular carcinoma (HCC)
Treatment for Hep B?
Avoid alcohol
Immunise sexual contacts
Those with chronic liver inflammation 2 options:
1) Boost immune system (IFNα) – Old, less effective
2) antiviral drugs
Side effects of anti viral medication
flu like illness, autoimmune disease,
Complications of chronic hepatitis
Uncontrolled liver inflammation (ALT & AST rise)
Fibrosis»_space;> Cirrhosis»_space;> Hepatocellular carcinoma
(Fulminant hepatic failure)
What is hepatitis C
RNA flavivirus
Spread by blood, transfusion, IVDU, sexual, acupuncture
Prevalent in UK
Early infection is mild/asymptomatic
85% develop silent chronic infection
25% get cirrhosis in 20yrs
Most Hep C infection go on to get chronic infection
What are risk factors for progression to chronic disease?
Male, Older, Higher viral load, Alcohol use
HIV, HBV
Diagnostic tests and results for Hep C
LFTs
Anti-HCV antibodies confirms exposure
HCV-PCR confirms on-going infection/chronicity
Biopsy if HCV-PCR +ve – assess liver damage and need for treatment
Treatment for Hep C
Direct acting antivirals- protease inhibitors
Combine with PEGinterferon-α and ribavirin, different success rates in different viral genotypes (not that effective against genotype 1)
What hepatitis are spread enterally?
Parenterally?
Enteral= Hep A and E
Parenterally= Hep B and C
Which viral hepatitis are acute?
Which can be chronic?
Hep A and Hep E are always acute
Hep B and C can progress to chronic
Describe general treatment for chronic hepatitis
Old= IFNa (stimulate immune response) and ribavirin (antiviral)
New= DAA (direct acting antivirals)
Protease inhibitors
Polymerase inhibitors
What is Hepatitis D
Incomplete RNA virus – needs HBV for assembly
HBV vaccination thus prevents HDV infection
5% of HBV carriers have HDV co-infection
May cause acute liver failure/cirrhosis
Tests for HDV?
Treatment?
Anti-HDV antibody
pegylated interferon-α has limited success
Liver transplant may be needed
What is Hepatitis E?
endemic in UK RNA virus Similar to Hep A Virus Waterborne faeco-oral transmissionor food borne Common in Indochina Mortality is high in pregnancy Associated with pigs (sausages!) Epidemics occur
Tests and treatment for Hep E
Tests – serology check for Hep E IgM and IgG
Treatment- IFNa + ribavirin AND DAA (non specific)
Ways to remember
E is Even in England and can be Eaten, if not always beaten
B is Blood-Borne and if not Beaten can Be Bad
B and D is DastarDly
C is usually Chronic but Can be Cured – at a Cost
