Hepatitis

Question 1

Classify Hepatitis A (“infectious hepatitis”)

Answer 1

• belongs to the picornavirus group (i.e. poliovirus)

- (+)ssRNA, not enveloped and icosahedral

Question 2

How does transmission of Hep A differ from Hep B and Hep C

Answer 2

Hep A is fecal oral while hep B and C are from blood/birth/sex

Question 3

99% of Hep A = no chronic infection. Symptoms are mainly due to

Answer 3

immune system

Question 4

Enzyme Immunoassay (EIA) to diagnose Hep A. If a patient has anti-Hep A IgM, then describe the type of infection she has

Answer 4

acute hep A

Question 5

If EIA reveals anti-hep A IgG, it will indicate

Answer 5

past infection/vaccination

Question 6

Hep A is a humorally controlled virus. Explain

Answer 6

It has one serotype; and IgG is protective

Question 7

Explain Hep A prophylasix

Answer 7

Give immune serum globulins (Gammagard)

Question 8

Classify Hepatitis B (“serum hepatitis”)

Answer 8

• belongs to hepdnavirus group
• dsDNA, enveloped
• CARRIES A REVERSE TRANSCRIPTASE & replicates thru an RNA intermediate

Question 9

T/F: There are vaccines against Hep A and B, but not C

Answer 9

True, b/c hep A and B only have one serotypes while hep C has about four

Question 10

4 stages of Hep B/immune interactions

Answer 10

1) immune tolerance -virus replicates without symptoms (serum Hep B DNA and Ag, but little Ab)
2) immunogenic symptoms -adaptive immunity response to virus causing increase in ALT and decrease in HepB DNA
3) Clearing the virus -viral replication closes down (can detect HBeAb detected; Hep B DNA not detected)
4) Virus cleared = no viral antigens

Question 11

Which hepatitis is “messy” and has lots of decoys evading humoral immunity?

Answer 11

Hep B & Hep C

Question 12

Classify Hep C genome

Answer 12

-part of flavivirus, RNA genome

Question 13

If EIA revealed positive Hep C test, why is it necessary to do a Recombinant Immunoblast Assay (RIBA)?

Answer 13

RIBA can confirm HCV exposure and detect false positives

Question 14

Unlike Hep A and B, immunoglobulins are not protective in Hep C. what is the drug regimen?

Answer 14

peg-IFN-Alpha + Ribavirin (nucleoside analog of guanosine)

Question 15

Goal of treatment in Hep C is

Answer 15

Sustained viral response (SVR)

Question 16

Efficacy of peg-IFNalpha in Hep C serotypes 2 &3 vs serotypes 1 &4

Answer 16

serotypes 2 & 3 = >50% SVR w/ 6 months of treatment while serotypes 1 & 4 require 1-2 yrs of treatment

Question 17

EIA of HepB: you detect viral surface antigen will indicate

Answer 17

acute hep B

Question 18

EIA of HepB: IgG against viral surface antigen

Answer 18

recovered/vaccinated

Question 19

Treatment with polymerase inhibitors + IFN has many side effects, often ineffective, new protease inhibitors are improving treatment of which hep C serotype?

Answer 19

serotype 1 but still has side effects

Question 20

Liver transplant alleviates liver failure, but if virus was not cleared from secondary sites of infection, new liver becomes infected. What should be done? Short course of antivirals preceding LDLT may be the answer.

Answer 20

Short course of antivirals preceding Living donor Liver Transplant may be the answer.