Micro hepatitis viruses

Question 1

hepatitis A virology

Answer 1

picornavirus; ssRNA, naked icosahedral capside; environmentally rugged; single serotype (no reinfection and vaccine)

Question 2

hepatitis A pathogenesis

Answer 2

fecal-oral - infects hepatocytes - often asymptomatic
causes acute hepatitis - NOT hepatotoxic - immunogenic response
1% fulminant hepatitis (quickly lose liver)

Question 3

hepatitis A on exam

Answer 3

fever, jaundice, gastroenteritis, tenderness around liver, dark urine, pale feces
history: vaccination? foreign travel, daycare, shellfish

Question 4

hepatitis A labwork

Answer 4

IgM = acute; IgG = resolved or vaccinated; serum ALT = liver damage

Question 5

hepatitis A treatment

Answer 5

rest, fluids, monitoring; discontinue alcohol and contraindicated meds

Question 6

hepatitis E virology

Answer 6

small, naked, icosahedral capsid, + ssRNA
one serotype
endemic to asia, africa, mexico

Question 7

hepatitis E pathogenesis

Answer 7

fecal-oral transmission similar to hep A (acute hepatitis usually resolves) but higher mortality especially in pregnant women!

Question 8

hepatitis E exam, labwork, treatment

Answer 8

exam: same as hep A (fever, ajundice, gastroenteritis.. travel?..)
labwork: serum ALT
treatment: same as hep A (rest, fluids, monitoring)

Question 9

hepatitis B virology

Answer 9

hepadnavirus (hepaDNAvirus) - enveloped, DNA genome, partly double-stranded
one serotype, no reinfection , vaccine

Question 10

how does hepatitis B evade immune system?

Answer 10

• replication produces many INCOMPLETE DECOYS!

- replication in hepatocytes leaves behind integrated viral DNA

Question 11

hepatitis B pathogenesis

Answer 11

transmitted by blood, sex, birthing
90% have acute hepatitis then clear virus
remaining 10% have fulminant or establish chronic infection

Question 12

complications of chronic hepatitis B infection

Answer 12

1. cirrhosis (ongoing cytotoxic attempt to clear virus)
2. kidney damage and arthritis (accumulation of antigen-antibody complexes)
3. hepatic cell carcinoma (integrated viral DNA and ongoing hepatocyte replacement in context or virus infection)

Question 13

hepatitis B labwork

Answer 13

serology for timecourse of infection: surface antigen, surface antibody, core antibody, E antigen

Question 14

what is anti-HBc indicative of?

Answer 14

no vaccine - prior infection!!

Question 15

hepatitis B treatment

Answer 15

acute: supportive

DAMAGING chronic: polymerase inhibitors and alpha-interferons

Question 16

prevention of hepatitis B

Answer 16

vaccination and immune globulin prophylaxis

Question 17

what is the relationship between hepatitis B and D?

Answer 17

B is a helper virus to D

Question 18

hepatitis D virology

Answer 18

viriod parasite of hep B
encodes single delta antigen (all other parts obtained from hepB infection same hepatocyte)
NOT capable of solo infection!!

Question 19

which is worse? co infection or superinfection by hepB+D

Answer 19

superinfection! (pre-existing hep B followed by D) - in co infection, D can’t infect all the way because it takes B a while to completely infect - a weak infection by D pretty much

Question 20

hepatitis D pathogenesis

Answer 20

spread by blood, sex - delta antigen is hepatotoxic - fulminant hepatitis likely

Question 21

hepatitis D labwork

Answer 21

EIA for delta antigen or antibodies against it

Question 22

hepatitis D treatment

Answer 22

none effective - liver transplant if meets criteria

Question 23

hepatitis C virology

Answer 23

favivirus - enveloped, +ssRNA

Question 24

difference in B and C immune evasion

Answer 24

B makes decoys, C has lots of mutations!

Question 25

hepatitis C pathogenesis

Answer 25

transmitted by blood, sex, 85% chronic infection with long latency
can proceed to liver failure which is mostly immunogenic

Question 26

hepatitis C exam

Answer 26

MILD acute hepatitis

diagnose by EIA followed by RIBA and genotyping

Question 27

hepatitis C treatment (second generation)

Answer 27

acute: pegalyted alpha interferon to reduce risk of chronic infection
chronic: attempt to achieve sustained viral response by combined therapy with:
1. ribavirin (viral chain terminator)
2. pegalyted alpha-interferon
3. HCV protease inhibitors: voceprevir or telaprevir

better for serotypes 2 and 3

Question 28

hepatitis C treatment (third generatioN)

Answer 28

1. simeprevir serotype 1 with IFN and ribavirin
2. sofosbuvir + ledipasvir
3. sofosbuvir + ribavirin for serotypes 2 and 3