Hepatitis

Question 1

hepatitis A virology

Answer 1

human restricted pocoronavirus. fecal-oral transmission. highly environmentally stable. neutralizing antibodies recognize virion proteins 1 and 3. IgG is protective against reinfection

Question 2

hepatitis A disease

Answer 2

predominantly portal and periportal lymphocytic infiltrate and a varying degree of necrosis. largely immunogenic symptoms. no chronic infection.

Question 3

hep A exam

Answer 3

jaundice, fatigue, anorexia, N/V, dark urine, pale feces. symptoms more severe the older you are

Question 4

hep A lab

Answer 4

IgM = acute infection
IgG = past infection, vaccination
ALT level high = ongoing liver damage
Bilirubin, aspartate aminotransferase, alkaline phosphatase will also be high during acute phase

Question 5

hep A treatment

Answer 5

prevention is best. vaccine exists. prophylaxis with immune serum globulin. Treatment is symptomatic: bed rest and hydration

Question 6

hepatitis E virology

Answer 6

small, naked ssRNA virus. fecal-oral transmission. main cause of acute hep in asia/africa. may have animal reservoir

Question 7

hep E disease

Answer 7

similar to hep A. mortality in preg women is 20% due to fulminant hepatitis, encephalopathy, DIC.

Question 8

hep E exam

Answer 8

biphasic infection.
Prodrome: fatigue, anorexia, N/V, diarrhea
Icteric phase: jaundice, dark urine, pale feces, leg rash but uncommonly

Question 9

hep E lab

Answer 9

HepE specific serodiagnostics are not widely available. High serum ALT, AST, bilirubin. Ultrasound to rule out biliary obstruction

Question 10

hep E treatment/prevention

Answer 10

boil water, cook shellfish, clean and/or cook produce. IgG prophylaxis not available. HEV239 vaccine is new, but good so far. no specific treatment available. Light activity (NO BED REST), fluid replacement, stop alcohol and contraindicated meds

Question 11

hep B virology

Answer 11

human restricted hepadnavirus. small, enveloped DNA virus, partly double stranded. Messy virus, 1000x more HBsAg decoys than virions. Unusually stable. HBsAb protective against reinfection. Carries reverse transcriptase and replicates through RNA intermediate. replicates in hepatocytes and leaves behind integrated copies of viral DNA

Question 12

hep B pathogenesis

Answer 12

transmitted efficiently by injection of contaminated blood, less efficiently by sex or birth contact.

Question 13

timecourse of HBV infection

Answer 13

surface antigen appears early. Surface antibody becomes detectable as surface antigen levels fall. It is raised by vaccine and infection. Core antibody arises later, stays (IgM for acute, IgG for resolved or chronic.) Core isnt raised by vaccine. E antigen is detectable when virus is most transmissible.

Question 14

4 stages of hep B

Answer 14

immune tolerance: virus replicates without symptoms. HepB DNA and antigens in serum, but little antibody.
Immunogenic symptoms: ALT increases, HepB DNA declines.
Clearing the virus: Viral replication shuts down, HBeAb detected, HepB DNA not detected, ALT declines, HBsAg remains.
Virus cleared: no viral antigens, permanent HBsAb IgG.

Question 15

Hep B chronic infection pathogenesis

Answer 15

ongoing cytotoxic T cell response against infected hepatocytes causes permanent cirrhosis. Virus itself is not hepatotoxic. Accumulation of Hep antigen-antibody complexes lead to kidney damage and arthritis. Virus genome integration, expression of viral transcriptional transactivators, and chronic inflammation can lead to cancer!

Question 16

hep B exam

Answer 16

asian born adult infected vertically as a newborn. Or socioeconomically disadvantaged sexually transmitted.

Acute phase: anicteric shows flulike or no symptoms

Icteric: jaundice, anorexia, N/V, myalgia, URQ pain, hepatomegaly

Chronic phase: spider angioma, hepatomegaly, palmar erythema, testicular atrophy, edema

Question 17

Hep B lab

Answer 17

serology panel for HepB antigens, anti-hepB antibodies, AST, ALT, bilirubin levels. Use imaging to rule out biliary obstruction. PCR testing may be performed. If infection is active chronic, do liver biopsy. Inflammation around portal tracts, ground glass cytopathology, positive staining for hepB antigens.

Question 18

hep B treatment

Answer 18

Vaccine! Prophylaxis with antibody. combo of both given for needle sticks and newborns from HBV positive mothers. provide supportive care for acute hepatitis. can give 1 year of polymerase inhibitors plus 4 months of pegylated alpha-interferon, which is super toxic. transplant indicated for late stage or failed treatment

Question 19

normal role of interferon

Answer 19

cell signalling! paracrine, endocrine, and autocrine

Question 20

hepatitis D virology

Answer 20

not a complete virus. cannot replicate by itself, only in cells co-infected with hepB. RNA virus. Virion exterior looks like HepB. spread by blood and sex

Question 21

which hepD antigen is cytotoxic

Answer 21

delta antigen! this increases the incidence of fulminant hepatitis in people with hepB

Question 22

superinfection vs. coinfection

Answer 22

coinfection: both viruses acquired at once. coinfection has same clearance rate as hepB alone.
superinfection: chronic hepB+ patient acquires HepD. many pre-existing hepatocytes infected with hepB which allows hepD to enter

Question 23

hepD diagnosis

Answer 23

on exam, same as hepB. primary screening with EIA for anti-delta antibodies. HepB serum panel with acute results if coinfection or chronic results if superinfection

Question 24

hepD treatment

Answer 24

best option: prevent hepB infection with vaccination or prophylaxis. Second best: if already hepB+, halt IV drug use, alcohol, treat hepB.
If actually infected with hepD, try pegylated alpha interferon

Question 25

hepC virology

Answer 25

human-restricted flavivirus. Enveloped RNA genome. transmitted efficiently by blood, inefficiently by sex. high potential for chronic infection. no vaccine.

Question 26

hep C pathogenesis

Answer 26

HCV infects hepatocytes and possibly B lymphocytes. highly mutagenic. less than half of the infectees clear it, requires a strong cytotoxic T response.

Question 27

HepC exam

Answer 27

acute symptoms similar to HBV but milder. mistaken for flu or mono. main patient population is baby boomers. red flag: travel to egypt. new infections usually from IV drugs. arthralgias, sicca syndrome, paresthesias, myalgia, pruritis. can cause liver failure

Question 28

hepC lab

Answer 28

liver function tests including ALT, albumin, bilirubin. EIA followed by RIBA. HCV genotyping. RT-PCR for viral RNA levels to assess success of therpay.

Question 29

RIBA for HCV, what is it?

Answer 29

recombinant immunoblot assay. used as a followup to confirm HCV exposure. Detects anti-HCV antibodies.

Question 30

hep C treatment

Answer 30

goal is sustained viral response. First gen: ribavirin + peg alpha. Second gen: ribavirin + peg alpha + HCV protease inhibitors
third gen: new drugs! protease inhibitors, polymerase inhibitors, etc. oral drugs!