Viral Hepatitis Flashcards
1
Q
Hepatitis-Syndrome
A
- Pathogens vary from Bacteria, Viruses, Parasites
- Inflammation of liver due infection to Hepatocytes
- Begins w/non-specific flu like symptoms
- Fever, anorexia, nausea, vomiting, ab pain
-
Viral Hep:
- Infectious (fecal-oral)-<u><strong>A & E</strong></u>
- Serum (blood borne)-<u><strong>B, D, C, & G (Rare)</strong></u>
- Signs-
- Elevated bilirubin
- Jaundice-Yellowed skin & mucous membranes
- Dark urine, pale stools, itching
- Elevated trasaminases (ALT/AST)
2
Q
Hep A (Gen)
A
- SS(+) RNA-Naked (72)
- 50-75% adults are sero+
- Fecal-oral (water/sea food-clams) w/Low infectious dose & virus sheds 2 weeks before symptoms
- Virulence: Stable @ PH1, detergents, 60c_(heat)_, drying, BUT killed with Cl-
- High risk: Summer camps, day care (group w/poor hygiene)
- IP: 15-50 days
- Adults <strong><em>acute onset-resolves spont</em></strong>
- <strong><em>Hep fulminant </em></strong>up to 80% mortality rate
- Blood infection through epi cells on oropharynx/GI
- Spreads to liver-Infect hepatocytes<u><strong>/Kupeffer cells</strong></u>
- T-cells/NK cells w/Ab comp=<strong>Tissue damage</strong>
3
Q
Hep A (Clinical)
A
- Diganose: Ab/Virus Conc
- IgM Anti-HAV present 5 days before symptoms
- IgG Anti-HAV present during infection (past infection)
- Hep A replicates in liver, excreted in Bile, sheds in stool
- Peak of infection is 2 weeks before onset of jaundice
- Treat: No drugs
- Active Immunization: Inactivated HAV vaccine (only 1 serotype)
- Give to all children @ 2
- Give to traverler’s & homosexuals
- Post-exposure w/in 2 weeks
4
Q
Hep B (Gen)
A
- Ds Circular DNA enveloped
- Replicates via RNA int-Codes for reverse transcriptase
- Viral DNA integrate w/cell chromosome (NO integrase enzyme-HIV)
- HBsAg (surface Ag)**-Detected in serum **
- HbcAg (core-Ag/Capsid)
- HBeAg (Capsid Ag secreted from infected cells)
- Transmission:
- Sexual-Multiple sex partners, Hookers, Homos
- Pareternal-Blood IV, Organ transplants (healthcare)
- Perinatal-Mothers <u><strong>HBeAG+</strong></u> babies infected via birth or breast feeding
- High Risk-IDU <strong>(IV user) </strong>& all transmission above
5
Q
Hep B (clinical)
A
- Cell med Immunity=Lysis of infected cells=<strong>SYMPTOMS</strong>
- HBsAg binding to anti-HBs=<strong>Autoimmune (rash/arthiritis)</strong>
-
Acute HepB-Self resolving 90%
- <em><strong>Anti-HBcIGM</strong></em>-Acute infection
- <strong>Fulminant Hep 1%</strong>=Altered brain function & fatal
- IP: 60-90 days
- Illness-Jaundice <strong>(weak CMI over 5 years)</strong>
-
Chornic Hep @ 6 months (<strong>weak CMI over 5 years)</strong>
- <u><strong>Anti-HBcIgG</strong></u>-Past or chronic infection
- HBsAg-Marker for infection
- HBsAb-Document recovery & immunity to HBV
- HBeAg-Active replication of virus & infectous
- Anti-Hbe-Virus stagnant <strong>(still carrier if HBsAg+)</strong>
6
Q
Hep B (Treatment)
A
- Acute-HBsAg, HBeAg, AntiHBc (+) & Anti S/E (-)
- 4-5 weeks after infection:
- <em><strong>HBsAg & anti-HBsAg</strong></em> NOT detectable but <em><strong>IgM anti-HBcAg</strong></em> is = <strong><u>“window period"</u></strong>
- 5-6 weeks after (resolved/convalescence):
- <u><strong>HBsAg(-)</strong></u> due to clearance by AntiHBs(+)& antiHBc (+)
- Chronic ACTIVE=HBeAg solo = Infectous
- Chronic PERSISTANT=HBeAg + anti-HBeAg = Non-infectous
-
Treat-Interferon A <u><strong>(polyeth glycol=long 1/2 life)</strong></u>
- Antivirals (reverse transcriptase inhibitors=Lamivudine)
-
Active immune-Recomb acellular vaccine(HBsAg)-<strong>cloned in yeast</strong>
- <strong>All newborns <u>(3 doses)</u>, Adults @ risk, Expecting mothers <u>(2 doses)</u></strong>
7
Q
Hep D
A
- ss Circular (-) RNA Enveloped-codes for HDAg
- Can <strong>ONLY</strong> replicate in cells infected by HBV & uses HBsAg for binding to hepatocytes
- Transmission similar to HBV (Needle sharing, tatoos)
- Infection of HDV is cytopathic (cell death)
- Coinfection: HDV + HBV (Severe Acute symptoms)
- HDVAg gone when HBsAg appears
- No HDVAb to show pt was once infected with Hep D
- Superinfection: HBV carrier + HDV (Chornic symptoms w/cirrhosis)
- IgG antibodies against HDV antigen persist
- _ Diagnose:_ HDVAg (acute phase) or Ab-HDVAg
8
Q
Hep C (Gen)
A
- ss RNA (+) enveloped w/6 serotypes
- Found in humans & chimps
- Transmission: Same as HBV w/Greater risk for chronic infection
-
_HIgh risk: _transfusion or transplant from infected donor
- Needles <strong>(60%)</strong>, multiple sex partners, Birth to HCV+ mother
- No cytopathic effect-Cell death due to CD-8 cells
- No Oncogenes-BUT causes carcinoma due to chronic damage <u><strong>(30 years)</strong></u>
- IP 6-7 weeks:
- Acute Hep w/resolution <u><strong>(presents like Hep A/B)</strong></u>
- Rapid onset of cirrhosis
-
Chronic persistent infection-w/regression to disease
- Liver failure or Cirrhosis <u>(20 years)</u>
9
Q
Hep C (Clinical)
A
- _Diagnosis: _
- HCV Ab-ELISA (Ab appear w/in 7-31 weeks) Cant differ between acute & chronic past infection
- RT-PCR <u>(HCV RNA)</u>=Diagnose acute & monitor response to anti-viral
- Treatment:
- Acute=Pegylated interferon A (50% success)
- Chronic=Pegylated Interferon A w/<em><strong>Ribavirin</strong></em> (active by kinases-Interferes w/viral RNA)
- Prevention: NO vaccine (screen blood donors)
10
Q
Hep E
A
- SS (+) RNA Naked w/1 serotype-_Resistant to inactivation_
- Transmission: Fecal-oral (drinking water)
- <strong>RARE </strong>cases due w/travel to endemic areas <u>(Asia, Middle East, Africa, Mexico)</u>
- High Risk: Similar to HAV w/High mortality in pregnant women (3rd trimester)
- E-NANABH=Disease
- IP 40 days
- Symptoms similar to HAV-Only acute infection
- Diagnsis: Looks like HAV (rule out A & B)
- **BEST is DIF (Direct immuno) of feces **
