Infectious Disease (Block 6): Week 2C

Front 1

Out of the Hepatitis viruses, which are DNA and which are RNA? Which are transmitted fecal-orally and which are parentally (via blood)? Which are capable of acute viral hep and which are capable of chronic hep?

Back 1

DNA - only Hep B (HBV)
RNA - all the rest

"Hep B is the Black sheep!"

A and E are the only ones that are transmitted fecal-orally. B,C,D are transmitted via blood

All the hep viruses are capable of acute viral hepatitis, but only B,C,D are capable of chronic hep

Front 2

hepatitis A is NAKED/ENVELOPED with __RNA (____ sense)

Back 2

NAKED, ss, positive

hep A is nice, naked and weaksauce (compared to hep B!)

Front 3

most common vaccine-preventable disease among unprotected travelers

Back 3

hep A (incubation period = 1 month)

Front 4

clinical manifestation of hep A

Back 4

acute viral hepatitis - self-limitng fever, malaise, nausea (often asymptomatic)

- inc liver enzymes (bc virus causes liver necrosis) and inc bilirubin (due to poor fxning of liver)

Front 5

T or F. risk of jaundice/fatal hepatitis increases with age.

Back 5

T.

Front 6

how do you diagnose Hep a?

Back 6

serology!!

anti-HAV IgM means currently active infection, whereas anti-HAV IgG indicates old infection and no active dz

Front 7

Hep E is part of the _____ family; it's structure is ENVELOPED/NAKED and ___ RNA.

Back 7

hepeviridae; NAKED; ssRNA (just like hep a!)

Front 8

what's the population with the highest rate of attack for hep E

Back 8

young adults/adolescents (due to possible sexual contact) though usually mode of transmitssion is fecal-oral

Front 9

compare incubation time of hep A vs. hep E

Back 9

hep A- 1 month
hep E - 45 days

Front 10

what population does hep E have a high mortality rate in? How do you Dx it?

Back 10

pregnant women (15-25% mortality rate)

dx: IgM or rising IgG to HEV

Front 11

Why is hepatitis B consided Big and Bad?

Back 11

Big - its a lot larger and TOUGHER than hep A (enveloped, dsDNA)

Front 12

replication in hep B utilizes what?

how does hepatic injury occur with hep B?

Back 12

RNA intermediate

injuty to liver most likely occurs due to CD8 killing of infected hepatocytes (hep b virus replicates in hepatocytes)

Front 13

HBsAg =_______
anti-HBsAg= _____

IgM anti-HBcAg= _______
IgG anti-HBcAg=______
Total anti-HBc

HBeAg=_______
anti-HBeAg=_______

which of the above antigens in Hep B is associated with liver cancer?

Back 13

incubation or current infection
immunity, cure, NO ACTIVE DZ!!

current ACUTE infection
old infection
current or prior infection

high infectivity, virus going wild!
low infectivity

HBeAg

Front 14

how is hep B transmitted

Back 14

parenterally (via body fluids like blood, wound exudates)

half of new infections in the US are sexually transmitted

Front 15

what heppens when a pregnant mother is HBeAg positive?

Back 15

this means that there's a hugely increased risk of neonatal infection with hep b and needs intervention (ie. baby needs vaccine)

Front 16

incubation period of hep b vs. hep a and hep e?

Back 16

hep b = 90 days
hep a = 1 month
hep e = 45 days

Front 17

young children are more like to develop ACUTE/CHRONIC infection of hep B

Back 17

chronic (but often asymptomatic)

risk of chronic infection dec with age; risk of symptomatic infection inc with age

Front 18

what are 2 complications of chronic infection with hep B?

Back 18

- hepatocellular carcinoma
- cirrhosis (permanent liver scarring and loss of hepatocytes)

Front 19

How do you prevent Hep B? (3)

Back 19

- vaccine of HBsAg
- post-exposure IgG
- screening of pregnant women for HBeAg
- universal immunization of infants

Front 20

treatment of chronic infections of Hep B (2)

Back 20

interferons (w/ or w/o steroids)
nucleoside analogues

Front 21

co-infection b/w what two hepatitis viruses is common?

Back 21

hep B and D

- in fact, hep D REQUIRES HBV infection (can't independently establish infection by itself)

"Hep D Depends on B"

Front 22

Hep D is uniquely coated with ____ antigen and is __RNA.

Back 22

coated with HBsAg
ssRNA (encodes delta antigen)

Front 23

what are the 2 ways HDV can infect humans?

Back 23

1) co-infect with HBV (enter parenterally at the same through IV drug use, blood transfusion, etc)==> generally resolves with anti-HBsAg, which ends both infetctions
2) superinfection: HDV infects person with chronic HBV infection==> severe and chronic infection of both because pt can't make anti-HBsAg (higher incidnce of fulminant hep, cirrhosis, chronic liver disease with higher mortality)

Front 24

Dx of hep D? vaccines?

Back 24

IgM anti-HDV - active infection
IgM anti-HBc - distinguishes co-infetion and superinfection

vaccine - prophylaxis before or after exposure with HBsAg vaccine to prevent HBV infection will prevent coinfection (best way to prevent is to control HBV infection)

Front 25

Which hepatitis viruses have single serotype?

which one has multiple genotypes?

Back 25

single serotypes - hep A and E (so vaccine is effective)
multiple genotypes - hep C (so drugs are less effective)

Front 26

most common cause of chronic viral hepatitis and liver disease requiring transplantation in the US

Back 26

hep C (bc most Hep C infections are chronic)

"C for Chronic!"

Front 27

structure of hep C; incubation period?

Back 27

enveloped, ssRNA (positive sense)

incubation - 6 wks

Front 28

which hepatitis viruses are associated with carcinoma?

Back 28

hep B and C

Front 29

clinical manifestations of hep C

Back 29

- acute infection (mostly asymptomatic) ==> followed by chronic infection and complicated by cirrhosis and liver cancer
- extra-hepatic manifetations (immune mediated like glomerulonephritis)
- associated with non-Hodgkin's B cell lymphoma

Front 30

Dx of hep c

Tx of hep C

Back 30

ELISA to screen
RIBA to confirm
PCR to monitor therapy

Tx: interferon and ribavirin
- avoid alcohol, vaccinate against HAV and HBV
- hepatic ultrasounds to test for liver cancer