L75 (Hep B & D) Flashcards Preview

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Flashcards in L75 (Hep B & D) Deck (27):
1

What does elevated AST/ALT indicate vs elevated bilirubin?

AST/ALT: liver injury
Bilirubin: liver dysfxn

2

Hep B
DNA or DNA?
Envelope?

SMALL
DNA - partially ds
Envelope

3

Important Hep B antigen proteins

Surface antigens
Core antigen
e antigen

4

Role of e antigen

Unknown
May buffer virus from immune response
USED as marker of viral replication

5

How is Hep B transmitted?

Blood = high [ ]
- Also wound exudates
Sexual = moderate [ ]
Peri-natal

6

Once Hep B gets to the liver via blood, how does it enter hepatocytes?

You don't know this

7

Where does Hep B replicate in hepatocytes?

Nucleus
partially dsDNA -> RNA -> totally dsDNA = cccDNA

8

Because Hep B is so small, how does it manipulate its genome to create the various proteins it needs?

Overlapping reading frames

9

What enzyme does Hep B carry?

RT
Duh! B/c it's a DNA virus!!

10

What is a common theme throughout hepatitis?

Immune response to the virus = 1ary liver damage
- T cells

11

What Ab shows acute Hep B infection? Chronic?

Acute = IgM
Chronic = IgG
DUH! Immunology 101!!!

12

What will you see on serology for acute Hep B?

Viral load - antigens & DNA only
Not enough time to create Ab response

13

Serology for resolved Hep B + other signs?

Surface antigen Ab
Core Ab
Both IgG
cccDNA !!! not in serum but permanently in cells!

14

Serology for chronic Hep B

Surface antigen present for 6mo
+/- e antigen
IgG core Abs
DNA
NO surface Ab!!! Weird

15

Progression of undiagnosed/treated Hep B

Fibrosis -> cirrhosis -> liver failure
Cancer!!!

16

Will most Hep B infected kids progress to chronic infection or not?

YES
Over 90%

17

Will most normal pts infected with Hep B progress to chronic infection or not?

NO
Less than 5%
Resolved: no additional surveillance

18

What is the difference between chronic hepatitis with or without e antigen?

+ e antigen = MUCH higher viral load

19

Who/why do you treat chronic Hep B?

Who:
- High viral load
- Active liver disease
Why: prevent progression

20

Treat Hep B

Prolonged course:
- Entecavir OR tenofovir
+ PegIFN

21

2 ways to prevent Hep B

1. Passive immunity = Hep B IG
- Temporary
- Post-exposure
- Babies of infected moms
- Within 24hrs, ineffective 7 days later
2. Vaccine

22

Hep D requires...

Hep B for infection!!1

23

Hep D transmission

IVDU

24

2 types of Hep D infection

1. Coninfection w/ B
2. Superinfection

25

Hep D structure

ssRNA --> codes for delta antigen
Hep B membrane!!!

26

Diagnose presence of Hep D

Ab in serum
RNA by PCR

27

Treat Hep D

Peg-IFN
Nucleos/tide analogues = INEFFECTIVE