Hepatitis

Question 1

How is Hep A spread and what population is it seen in?

Answer 1

It is spread by faecal-oral or shellfish

It is endemic in Africa and s America so seen in returning travellers, most infections in children

Question 2

What are the symptoms of hep a?

Answer 2

Incubation period 2-6 weeks
Fever, malaise, anorexia, nausea
Go on to develop jaundice, hepatosplenomegaly and adenopathy

Question 3

How do IgM and IgG antibodies vary in an individual infected with hepatitis?

Answer 3

IgM is seen after 25 days and implies recent infection

IgG is detectable for life

Question 4

What tests should be done and what will they show for hep A?

Answer 4

AST and ALT will rise 20-40 days after infection and return to normal 5-20 weeks
IgM will be present after 25 days showing recent infection and IgG will be present for life

Question 5

How is hep A infection treated?

Answer 5

Supportive treatment
avoid alcohol
Interferon alfa (antiviral) is given in rare circumstances for fulminant hepatitis

Question 6

What is fulminant hepatitis?

Answer 6

massive necrosis of liver parenchyma and a decrease in liver size (acute yellow atrophy) that usually occurs after infection with certain hepatitis viruses

Question 7

What is the mechanism of interferon alfa?

Answer 7

It causes increased expression of HLA-1 molecules that increases the activation of memory cd8 t cells which increases antiviral action

Question 8

How is hep A vaccinated against?

Answer 8

With an inactivated viral protein that gives immunity for one year unless booster given at 6-12 months which gives 20 years immunity

Question 9

What is the prognosis of hep A?

Answer 9

Usually self limiting

Question 10

How is hep B spread and what population is it seen in?

Answer 10

It is spread by blood to blood transfer either by sexual contact or through mixing blood e.g. IV drug users
At risk groups include: Iv drug users, health workers, haemophiliacs (impaired clotting), MSM, haemodialysis, sexually promiscuous

Question 11

What are the signs of hep B?

Answer 11

Resembles hep A but urticarial is commoner

Question 12

What is the incubation period of hep B?

Answer 12

1-6 months

Question 13

What is HBsAg? how long is it present for?

Answer 13

It is hep b surface antigen and is present 1-6 months after infection

Question 14

What is HBeAg? how long is it present for?

Answer 14

This is hep B e antigen and it is present 1-3 months after infection
This implies high infectivity

Question 15

What does hep B surface antigen being present after 6 months imply?

Answer 15

This means that the individual has carrier status and occurs in 5-10% of people
biopsy may be indicated

Question 16

What do antibodies to HBc (core) imply?

Answer 16

That there has been some past infection

Question 17

What do antibodies to HBsAg alone imply?

Answer 17

Vaccination

Question 18

How is Hep B treated?

Answer 18

Refer for antivirals (interferon alfa-2a or long term but better tolerated nucleotide analogues e.g. tenofevir)
Avoid alcohol
Aim to clear HBsAg and prevent cirrhosis
hepatocellular carcinoma risk is greatly increased if HBsAg positive

Question 19

How is hep C spread and what population is it seen in?

Answer 19

Spread by blood and seen in similar population as hep B

Question 20

What are the signs and symptoms of hep C?

Answer 20

Asymptomatic often
85% get silent asymptomatic infection
25% get cirrhosis

Question 21

What tests are done for hep C?

Answer 21

LFTs, anti-HPV antibodies shows exposure
PCR confirms ongoing infection
Liver biopsy to assess need for treatment
Determine HCV genetype for treatment

Question 22

How is hep C treated?

Answer 22

Now considered almost curable due to good antivirals

e.g. ledipasvir

Question 23

How does hep D often get transmitted?

Answer 23

5% of hep B carriers also have hep D

Question 24

How is hep D treated?

Answer 24

Interferon alfa doesn’t work very well so often liver transplant

Question 25

Which other hepatitis is hep E similar to?

Answer 25

Hep A, has no specific treatment

Question 26

What is the cause of autoimmune hepatitis?

Answer 26

Unknown cause with abnormal t cell function and autoantibodies against hepatocyte surface antigens

Question 27

How does autoimmune hepatitis present?

Answer 27

It typically presents in young or middle aged women and has the signs of acute hepatitis (fever malaise etc.)
Can also present with gradual jaundice or asymptomatic