Viral Hepatitis Flashcards Preview

Sem 2 - Infection > Viral Hepatitis > Flashcards

Flashcards in Viral Hepatitis Deck (17)
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1
Q

Define hepatitis

A

Inflammation of the liver

Many systemic viruses cause “collateral” liver damage.

  • eg EBV, CMZ, VZV.

Hepatitis viruses

  • Replication specifically in hepatocyes (hepatotropic)
  • Destruction off hepatocytes.
2
Q

What liver function tests can be conducted?

A
  • Bilirubin
  • Liver transaminases
    • ALT - alanine transaminase
    • AST - aspartate aminotransferase
    • Test for hepatocyte damage / cellular integrity
  • Alkaline phosphatase (ALP)
    • Bilary tract cell damage / cholestasis
  • Albumin
    • A protein synthesised in liver
  • Tests of coagulation
    • Clotting factors are synthesised in liver
    • INR
    • PT (prothrombin time)
3
Q

Who is at risk of contracting Hep B?

A
  • Vertical transmission (75% cases globally)
    • Perinatal transmission in pts from highly endemic areas
  • Sexual contact
  • IV drug users
  • Close household contacts
    • Significant blood exposure
  • HCW via needlestick injuries
4
Q

What are symptoms of acute Hep B?

A
  • Jaundice
  • Fatigue
  • Abdominal pain
  • Anorexia / Nausea / Vomiting
  • Arthralgia (pain in a joint)
5
Q

Acute Hep B

A
  • Incubabtion 6wks-6months
  • AST / ALT in 1000s
  • Up to 50% - no/vague symptoms
  • Clear infection within 6 months
  • < 1% - fulminant hepatic failire
  • Becomes chronic in under 10% if infected as an adult whereas, 90% if infected in infancy (China / Asia)
6
Q

Hep B serology

A

HBsAg - HBsAb (Surface antigen / Surface antibody)

HBeAg - HBeAb (e-antigen / e-antibody)

HBcAg - HBcAb: IgM and IgG (Core antibody / core antigen)

Ag = antigen

Ab = antibody

7
Q

What is the response to Hep B?

A
  1. Surface antigen first - confirms Hep B
    1. Within 6/52; rise in ALT / DNA
  2. Followed by a-antigen
    1. Highly infectious
  3. Core antibody (IgM)
    1. First antibody to appear
  4. Followed by e-antibody
    1. Herelds dissappearance of e-antigen, less infectious
  5. Surface antibody
    1. Last antibody to appear
    2. Clearance of virus / recovery
  6. Core antibody (IgG)
    1. Persists for life.
8
Q

Define Chronic Hep B

A

Persistance HBsAg (surface antigen) after 6 months

25% chronic infection leads to cirrhosis and about 5% will develop hepatocellular carcinoma

9
Q

What is the treatment of chronic Hep B?

A
  • NO CURE integrates into host genome
  • Life-long anti-virals to suppress viral replication
  • Not required for everyone (e.g. inactive carrier)
    • Low viral load / Normal liber function tests / No liver damage
    • If immunocompormised ect.. then it can reactivate so, need to monitor life long.
10
Q

Hep B Vaccination?

A
  • Genetically engineered surface antigen
  • 3 doses + boosters if required
  • Effective in most people
  • Produced surface antibody respose
    • >10adequate
    • >100 long-term protection
11
Q

Who is at risk of Hep C?

A
  • People who inject drugs (IV) over 90% of those with Hep C in the UK.
    • IV heroin / crack / metamphetamines
    • Crack or heroin smokers
  • Sexual contact (less than 1% bit higher if HIV co-infected)
  • Infants born to HCV positive mothers (less than 5%)
  • Blood transfusions prior to 1991
  • Needlestick injuries to healthcare workers ect.
12
Q

How does Hep C progress?

A

80% become chronically infected.

Of these some will develop chronic liver disease / cirrhosis

Resulting in:

  • Decompensated liver disease
  • Hepatocellular carcinoma (primary liver cancer)
  • Transplant
  • Death
13
Q

Symptoms of Hep C?

A

80% have no symptoms (acute or chronic)

20% have vague symptoms

  • Fatigue
  • Anorexia
  • Nausea
  • Abdominal pain (RUQ)
14
Q

Hep C serology

A
  • Anti-Hep C antibody only.
  • Remain positive life longe, even after clearance / cure
  • Antibody is NOT protective, can get re-infected.
  • Viral PCR - if positive, confirms on-going / chronic infection.
15
Q

Treatment of Hep C

A

Can be cured!

  • Directly acting antiviral drug combo
  • 8-12 weeks
  • >90% chance of cure
  • £10,000 per course! (Can be more… Used to be MUCH higher!)
  • Can get re-infected

BUT, no vaccine

16
Q

What is the risk of transmission of HIV, Hep B, Hep C from needlestick injury?

A

HIV - 1/300 Much lower if patient is on ARVs or if viral load is undetectable

Hep C - 1/30

Hep B - 1/3 Much lower if recipient has been vaccinated

17
Q

What do you do if a needlestick injury has occured?

A
  • First aid - bleed and wash wound
  • Collect blood from patient (with consent) and from med student
  • Inform Occupational Health
  • Check med student’s Hep B vaccination
  • Assess risk and need for immediate HIV PEP
    • HIV PEP -early initiation of ARVs reduces dissemination and replication of HIV in tissue and bodily fluid.