11. Viral Hepatitis

Question 1

What are hepatitis viruses?

Answer 1

Replication specifically in hepatocytes

Destruction of hepatocytes

Question 2

What is the incubation period for hep B?

Answer 2

6 weeks to 6 months

Question 3

What is the incubation period for hep C?

Answer 3

6-12 weeks

Question 4

What is the viral structure of hep B?

Answer 4

DNA, double stranded, enveloped

Question 5

What is the viral structure of hep C?

Answer 5

RNA, single trained, positive strand, enveloped, icosahedral

Question 6

What are the types of jaundice?

Answer 6

Prehepatic - haemolysis (excess RBC breakdown)
Cholestatic intrahepatic - viral hepatitis, drugs, cirrhosis, pregnancy
Cholestatic extrahepatic - common duct stones, carcinoma of bile duct, head of pancrease or ampulla

Question 7

What are the liver function tests?

Answer 7

Bilirubin
Liver transaminases - alanine transaminase, aspartate aminotransferase
Alkaline phosphatase
Albumin
Tests of coagulation

Question 8

What does it mean is ALT and AST are raised?

Answer 8

Hepatocyte damage/cellular integrity

Question 9

What does it mean iff ALP is raised?

Answer 9

Biliary tract cell damage/cholestasis

Question 10

Who is at risk of transmission of hep B?

Answer 10

Vertical transmission is main transmission
Sexual contact
People who inject drugs
Close household contacts (significant blood exposure)
HCW via needlestick injuries

Question 11

What are the symptoms of acute hep B?

Answer 11

Jaundice
Fatigue
Abdominal pain
Anorexia/nausea/vomiting
Arthralgia

Question 12

Describe the acute hep B on body

Answer 12

AST/ALT in 1000s
Up to 50% no/vague symptoms
Clear infection within 6 months
Becomes chronic in <10% if infected as adult, 90% if infected in infancy

Question 13

Describe hep B serology

Answer 13

1. Surface antigen first (HBsAg) - within 6/52, rise in ALT/DNA
2. Followed by e-antigen (HBeAg) - highly infectious
3. Core antibody (HBcAb: IgM) - first antibody to appear
4. Followed by e-antibody (HBeAb) - Heralds disappearance of e-antigen and infectivity
5. Surface antibody - last antibody to appear, clear ace of virus/recovery
6. Core antibody (IgG) - persist for life

Question 14

What is chronic hep B infection?

Answer 14

Persistence of HBsAg after 6 months

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

Question 15

What is the treatment for hep B?

Answer 15

No cure
Life-long anti-virals to suppress viral replication
Not required for everyone

Question 16

What is the hep B vaccination?

Answer 16

Genetically engineered surface antigen
3 doses and boosters if required
Effective in most people
Produces surface antibody response

Question 17

Who is at risk of transmission of hep C?

Answer 17

People who inject drugs
Sexual contact
Infants born to HCV positive mothers
Blood transfusion prior to 1991
Needlestick injuries to HCW

Question 18

What is the disease progression of hep C?

Answer 18

80% become chronically infected
Of these some will develop chronic liver disease/cirrhosis resulting in: decompensated liver disease, hepatocellular carcinoma, transplant, death

Question 19

What are the symptoms of hep C?

Answer 19

80% have no symptoms

20% have vague symptoms (fatigue, anorexia, nausea, abdominal pain)

Question 20

What blood tests are done for hep C?

Answer 20

Serology - anti-hep C antibody only
Remains positive life-long, even after clearance/cure
Viral PCR - if positive confirms on-going/chronic infection

Question 21

What is the treatment for hep C>?

Answer 21

Can be cured
Directly acting antiviral drug combo - 8-12 weeks, >90% chance of cure, can get re-infected
No vaccine

Question 22

What is the rationale for HIV PEP?

Answer 22

Early initiation of ARVs reduces dissemination and replication of HIV in tissue and bodily fluid