Hepatitis (liver symposium) Flashcards
What causes viral hepatitis?
Hepatitis A, B, C, D & E
What type of virus is each type of Hepatitis?
Hep A & E are enteric viruses
Hep B, C, D are parenteral viruses
What is the difference between an enteric and parenteral virus?
Enteric means the virus enters the body through the mouth/ingestion
Parenteral means the virus enters the body by any way other than the mouth/alimentary canal
What is the nature of infection by hepatitis A or hepatitis E?
A & E cause Self limiting acute infections
What is the nature of infection by Hepatitis B, C or D?
B, C & D cause chronic infections
How many people are killed by Viral hepatitis every year?
~1 million
Where is Hepatitis A most prevalent?
High prevalence in:
- South America
- Africa
- Middle east
- Asia
- Greenland
What does Viraemia mean?
Presence of virus particle in the blood
What signs in the blood would indicate infection with Hep A?
(look at the table for this)
During clinical illness - which of these is elevated?
Viraemia - present for 6 weeks after inf.
ALT - indicates liver damage - highest 4 weeks after inf.
IgM - highest 4 weeks after inf.
IgG - steady increase from 3rd week onwards
Clinical illness - ALT & IGM elevated most
What is the transmission route for Hep A?
Faecal - oral
sexual
blood
Who is most at risk of infection by Hep A?
5 - 14 year olds
What clinical biomarker is used to diagnose Hep A infection?
IgM antibodies
What groups of people should be immunised against Hep A?
Travellers
Patients with chronic liver disease
- IDU (especially with HCV or HBV)
Haemophiliacs
Occupational exposure
- lab workers
- big medical lads
Men who have sex with men (MSM)
Where in the world is Hep B most present?
Canada, Alaska, Greenland
Parts of South America, Asia and most of Africa
HBV has several antigens which can be used to detect its presence in the blood
What are these antigens?
HBsAg - surface antigen
HBeAg - ‘e’ antigen
HBcAg - core antigen (cant be detected in blood tho)
(HBV DNA can also be used) - not antigen
What does each HBV antigen indicate about the virus’ activity in the body?
HBsAg (surface ant) only indicates the presence in the blood
HBeAg & HBV DNA indicate Active replication
HBcAg also indicates active replication, but cant be detected so is pretty useless
Certain Antibodies to HBV in the body have different purposes/indications
What are the different types of HBV antibodies and what do they indicate?
Anti-HB’s = protection
IgM anti-HBc = ACUTE INFECTION
IgG anti-HBs = Chronic infection / exposure
Anti HBe = inactive virus
Summarise how someone with an acute HBV infection would be tested for/diagnosed?
1) HBsAg test = postive? \/ 2) Clinical evidence of acute infection? \/ 3) IgM anti-HBc test = Positive? \/ 4) Congrats
Chronic Hepatitis B has a detrimental effect on which organ in the body?
Describe how
Liver
Chronic infection causes damage which may cause Cirrhosis
Cirrhosed liver over time may develop Hepatocellular carcinoma (HCC) and finish with End Stage liver disease (ESLD)
What are the 2 main treatment options for HBV infection?
Oral antiviral drugs
Pegylated interferon
What are the Oral antiviral drugs available for use against HBV?
Lamivudine
Adefovir
Entecavir!
Telbivudine
Tenofovir
Hep C infections are most commonly ______
Chronic (85%)
What are the potential effects of infection by Hep C?
Jaundice - 10% of patients
Acute liver failure - Rarely causes this
Sometimes Liver cirrhosis with possible progression to HCC - leading cause of liver transplantation in the UK
What is the risk of someone with HCV infection getting liver cirrhosis?
20% of people with a Chronic HCV infection will develop liver cirrhosis
25% of these people with Liv Cirrhosis will develop Hepatocellular carcinoma (HCC)
Describe the blood stuff pattern of a patient infected with HCV (who recovers)
- 2/3 months after infection - ALT levels in the blood reach maximum level
- Anti HCV levels rise steadily and plateau at maximum after about 1 year
- HCV RNA can be detected in the blood for about 6 months after infection
Classically, what drugs were used to treat HCV infection?
PEGylated IFN alpha
Ribavirin
What drugs are used nowadays to treat HCV infection?
PEGylated IFN
What features of Hep D virus make it different to other Heps?
Small RNA virus:
- Doesnt code for its own protein coat
- Enveloped by HBsAg
Co-infects or super-infects alongside Hep B
(transmits in same way)
Very resistant to treatment
Where is Hepatitis E found most?
Asia
Mexico
Parts of Africa
Becoming increasingly recognised in the UK
Is HEV a problem in the UK?
Commonest cause of acute hepatitis in NHS grampian
How does HEV infection tend to progress?
Self limiting, with no long term sequelae
What are the treatment/vaccination options for HEV?
No effective vaccine
No specific treatment (but its self limiting so who cares eh)
