Viral Hepatitis

Question 1

Hepatitis viruses

Answer 1

Hepatitis = inflammation of the liver

Question 2

Viral structure

Answer 2

HepB - DNA - double stranded and enveloped

HepC - RNA - single stranded, positive strand and enveloped

HepE + A - RNA - single stranded, positive strand, non enveloped

Question 3

Production and excretion of bilirubin

Answer 3

Hb from RBC is taken up after RBC death and broken down into bilirubin

This bilirubin is transported to the liver attached to albumin

In the liver it becomes conjugated bilirubin by UDP glucuronyl transferase

Now conjugated it can now be transported in the blood to the SI for excretion (excreted as urobilinogen) - eventually it either ends up in the faeces or in the urine

Question 4

Liver function tests

Answer 4

Bilirubin - check to see if its being broken down

Liver transaminases
	Alanine transaminase (ALT)

Question 5

Hep B - transmission - who is at risk

Acute symptoms

Serology

Chronic symptoms and infection

Vaccination

Answer 5

Who is at risk? - 
Vertical transmission (75% cases globally) (from mother to child)

Perinatal transmission in patients from highly endemic areas

Sexual contact

People who inject drugs

Close household contact - people who experience significant blood exposure

Acute Hep B -
Symptoms - jaundice, fatigue, abdominal pain, anorexia, nausea, arthralgia (joint pain)

Incubation 6 weeks to 6 months

AST/ALT in 1000s

Most people dont get symptoms or symptoms are very vague

Usually a clear infection within 6 months
<1% have hepatic failure
Becomes chronic in <10% if infected as an adult - but 90% if infected in infancy

hepatitis B serology

1) Surface antigen first - Within 6/52; Rise in ALT / DNA
2) Followed by e-antigen - Highly infectious
3) Core antibody (IgM) - First antibody to appear
4) Followed by e-antibody - Heralds disappearance of e- antigen + infectivity
5) Surface antibody - Last antibody to appear - Clearance of virus/recovery
6) Core antibody (IgG) - Persists for life

Chronic Hep B infection -
Persistence of HBsAg after 6 months.
25% chronic infection leads to cirrhosis and ~5% will develop hepatocellular carcinoma.

Treatment - NO CURE

Question 6

Hepatitis C - who is at risk

Disease progression

Symptoms and blood tests

Treatment

Answer 6

Who’s is at risk? -

People who inject drugs (

Question 7

Risk of transmission from a needlestick injury from HIV, HEPB/C

Answer 7

HIV - 1/300 - Much lower if patient is on Ant-retrovirals / VL undetectable