Viral Hepatitis (A and E)

Question 1

Define Viral Hepatitis?

Answer 1

Hepatitis caused by infection with the RNA viruses, hepatitis A or hepatitis E virus, that follow an acute course without progression to chronic carriage

Question 2

What is the virus causing Hepatitis A VIrus (HAV)?

Answer 2

Picornavirus

Question 3

What is the virus causing Hepatitis E Virus (HEV)?

Answer 3

Calicivirus

Question 4

What is the transmission for HAV and HEV?

Answer 4

Faecal-oral route

Question 5

What is the aetiology of HAV and HEV?

Answer 5

Both viruses replicate within hepatocytes and are secreted into bile
Liver inflammation and hepatocyte necrosis is caused by the immune response
Infected cells are targeted by CD8+ T cells and NK cells

Question 6

What are the histological features of HAV and HEV?

Answer 6

Inflammatory cell infiltration of portal tracts
Zone 3 necrosis
Bile duct proliferation

Question 7

What is the epidemiology of HAV and HEV?

Answer 7

HAV is endemic in the developing world
Infection often occurs sub-clinically
Better sanitation in the developed world means that it is less common, age of exposure is higher and, hence, patients are more likely to be symptomatic
HEV is endemic in ASIA, AFRICA and Central America

Question 8

What is the Incubation Period of HAV and HEV?

Answer 8

3-6 weeks

Question 9

What are the Prodromal Period Symptoms of HAV and HEV?

Answer 9

Malaise
Anorexia
Fever
Nausea and Vomiting

Question 10

What are the Hepatitis Symptoms of HAV and HEV?

Answer 10

Dark urine
Pale stools
Jaundice lasting around 3 weeks
Occasionally, itching and jaundice may last several weeks in HAV infection

Question 11

What are the signs of HAV and HEV on physical examination?

Answer 11

Pyrexia 
Jaundice 
Tender hepatomegaly
Spleen may be palpable 
Absene of stigmata of chronic liver disease (although some spider naevi may appear transiently)

Question 12

What investigations do you do for HAV and HEV?

Answer 12

Bloods
Vital Serology
Urinalysis

Question 13

What bloods do we do for HAV and HEV?

Answer 13

LFTs
High ESR
Low albumin + high platelets (if severe)

Question 14

What do we look for on the LFTs for HAV and HEV?

Answer 14

High AST
High ALT
High ALP
High Bilirubin

Question 15

What do we look for on the vital serology for HAV?

Answer 15

Anti-HAV IgM (during acute illness, disappears after 3-5 months)
Anti-HAV IgG (recovery phase and lifelong persistence)

Question 16

What do we look for on the vital serology for HEV?

Answer 16

Anti-HEV IgM (raised 1-4 weeks after onset)

Anti-HEV IgG

Question 17

What do we look for on the Urinalysis for HAV and HEV?

Answer 17

Positive for bilirubin

Raised urobilinogen

Question 18

What is the general management plan for HAV and HEV?

Answer 18

No specific management other than bed rest and symptomatic treatment (e.g. antipyretics, antiemetics or cholestyramine (for severe pruritus))

Question 19

What is the prevention and control of HAV and HEV?

Answer 19

Public Health - safe water, sanitation and food hygiene
These are notifable disease
Immunisation is available for HAV

Question 20

What are the two type of immunisations that are available for HAV?

Answer 20

Passive immunisation with IM human immunoglobulin (effective for a short time)
Active immunisation with attentuated HAV vaccine offers safe and effective immunity for those travelling to endemic areas and high-risk individuals

Question 21

What are the possible complications of HAV and HEV?

Answer 21

Fulminant Hepatic Failure (in a very small proportion of patients but is more common in pregnant women)
Cholestatic hepatitis with prolonged jaundice and pruritus can develop after HAV infection
Post-hepatitis syndrome: continued malaise for weeks to months

Question 22

What is the prognosis for patients with HAV and HEV?

Answer 22

Recovery is usually within 3-6 weeks
Occasionally patients may relapse during recovery
There is no chronic sequelae
Fulminant hepatic failure has a mortality of 80%