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Flashcards in Microbiology of the Liver Deck (27)
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1
Q

what is the most common reason for liver transplantation?

A

viral hepatitis

2
Q

Out of the all the different types of hepatitis:

  • which ones are acute?
  • which ones are chronic?
  • which ones are faeco-oral route?
  • which ones are sex/permucous transmission?
  • which ones have immunisations?
A

1) A+E (think acute - go to a&e)
2) C,B,D
3) a+e (when your in a&e you hav a shit time)
4) C, B,D
5) A, B, D

3
Q

How is Hep A diagnosed in acute and past infection setting ?

EIA -enzyme immune-assay to detect for an antigen.

What is the treatment for Hep A?

A

Acute - EIA detects IgM for Hep A virus
Past infection = EIA detects IgG

No treatment - do LFTs to ensure liver is healing.

4
Q

How is Hep B diagnosed?

Treatment for Hep B?

A

Blood test for HBV surface antigens: HBsAg

1 - interferon
2 - Lamivudine (inhibits reverse transcriptase)

5
Q

How (when) is Hep C diagnosed?

Treatment for Hep C?

A

Antibody test for HCV works 4 weeks after infection

1 - Interferon
2 - Ribavirin - RNA synthesis inhibitor

6
Q

Pathophysiology of Hep B and C

A

Chronic perisistent hepatitis (asymptomatic)
Chronic active hepatitis
Cirrhosis
HCC

7
Q
  • Do children always develop chronic infections after Hep B infection?
  • Do adults always develop chronic infection after a Hep B infection?
A

90% of the time, yes

Only 5% of the time

8
Q
  • What are the common and uncommon causes of viral hepatitis?
  • In what groups are the ‘uncommon’ sources of infection actually more common than the ‘common’ sources of infection?
A
Common
Hepatitis A (HAV)
Hepatitis B (HBV)
Hepatitis C (HCV)
Hepatitis D (HDV)
Hepatitis E (HEV)
Uncommon
Adenovirus
Cytomegalovirus (CMV)
Epstein-Barr virus (EBV)
Herpes simplex virus (HSV)

In the immunosuppressed.

9
Q

• Which are the enteral hepatitis-causing viruses? Enteral = in the gut,

A

so HAV and HEV are the enteral pathogens. These cause the acute, self-limiting infections.

10
Q

• Which of the common viruses resembles a plant virus?

A

HDV

11
Q

• What are the signs and symptoms of someone with an acute viral hepatitis?

A
o	Main three to remember are:
1.	Jaundice
2.	Fever
3.	RUQ pain
o	Others include loss of appetite, nausea, vomiting, dark urine, pale stools, hepatomegaly, joint pain
12
Q

• In what body fluids is Hep B the highest?

A

o Highest in blood

o Intermediate in semen, vaginal fluid and saliva

13
Q

What is the first line diagnostic technique for Hep B?

Why is this unique?

A

Serology for the surface polypeptide that Hep B makes in massive amounts. HBsAg

This is unique because all the other Hepatitides are diagnosed using PCR.

14
Q

• What is the e antigen? HBeAg

A

The hepatitis antigen that suggests an active and replicating HBV infection if you find lots of it on a blood test. This implies high infectivity.

15
Q

• How does HBV replicate?

A
  1. DNA gets inside nucleus
  2. Covalently closed circular DNA, cccDNA, is formed (i.e. the DNA becomes a ring)
  3. This DNA is transcribed so that new particles can be made
16
Q

• Is cccDNA present in people who don’t have an active Hep B infection?

  • theoreticallly how can you get rid of cccDNA?
A

Yes, the cccDNA can hide in the hepatocytes without causing an active infection. Hence why people can develop a chronic HepB years after intial infection in periods of immunosuppression. Theoretically the only way to get rid of this cccDNA is to have a liver transplant.

17
Q

• If you acquire Hep B early, are you more or less likely to develop chronic HepB?

A

o If you’re young, you’re more likely to develop chronicity

o If you’re old, you’re more likely to clear the virus

18
Q

• What serological markers are present during a typical course of HBV infection?

Post infection:

At 1 month:
At 2 months:
At 3 months:
At 6 months:

A

1 month: HBsAg (hep B surface antigen appears)

2 months: HBeAg (e antigen) tells you that virus is replicating quickly + pt is very infectious.
Anti- HBc (antibody against HBV core present all the wat through from 2 months onwards - start off as IgM and end up as IgG - keep for life)

3 months: anti-HBe antibodies appear against HBeAg and antigen disappears.

6 months: anti-HBs antibodies appear and HBsAg disappears.

As antibodies appear the corresponding antigens disappear.

19
Q

what does the HBV vaccination involve?

A

Injection of the HBsAg so that your body makes anti-HBs, which will protect you from a later infection.

20
Q

• How does the serology compare of someone who has had HBV in the past versus someone who has been immunised to HBV in the past?

A

o They both have anti-HBs antibodies
o Only the person who has been infected with actual HBV in the past will have the IgG antibodies against the HBV core protein (Anti-HBc)

21
Q

Relevance if raised:

1) HBV surface antigen: HBsAg
2) HBV core antibody (IgM type) Anti-HBc IgM
3) HBV core antibody (IgG type) Anti-HBc
4) HBV e antigen: HBeAg
5) HBV e antibody: Anti-HBe
6) HBV surface antibody: Anti-HBs

A

1) means you’re infected (acute or chronic )
2) had a recent infection
3) infection in the past
4) infected and have a high viral load - very infectious
5) been infected in the past
6) infected in the past or immunised

22
Q

• What would be an ideal therapy for HBV infection for the future?

A

A cccDNA antiviral

23
Q

• How do you define chronic hep B?

A

On-going infection (so you have HbsAg) for >6 months

24
Q

HEPATITIS A

1) is there a vaccine?

3) what is the treatment?
4) why does it pose an infection control risk?
5) Why can you never get Hep A twice?

A

1) yes

3) merely supportive (check LFTs and clotting)
4) HAV is found in stool of infected patient.
5) IgG response is lifelong.

25
Q

HEPATITIS C

1) transmission?
2) type of virus?
3) high risk in what pts?
4) curable?
5) leads to cirrhosis and HCC quicker than which type of Hep virus?

A

1) blood
2) ssRNA flavivirus
3) IVDU
4) curable
5) HBV

26
Q

HEPATITIS D

1) always a co-infection with which type of hepatitis?
2) danger?
3) transmission

A

1) HBV
2) fulminant hepatitis (very severe)
3) bodily fluids

27
Q

HEPATITIS E

1) transmission?
2) fulminant hepatitis in what type of pts?

A

1) foodborne - raw beef

2) pregnant women