Unit 5: Section 1

Question 1

Hep A: mode of transmission, clinical syndromes, incubation periods, risk for development of chronic hepatitis, and distinctions related to epidemiology.

Answer 1

Transmission: Fecal, oral
Incubation period: about 28 days
Clinical syndromes: acute illness, self-limited
Risk for development of chronic: Very unlikely
Distinctions:Associated with outbreaks, general decline in US with slight recent increase, VACCINE

Question 2

Hep B: mode of transmission, clinical syndromes, incubation periods, risk for development of chronic hepatitis, and distinctions related to epidemiology.

Answer 2

Transmission: Parenteral, sexual and perinatal
Incubation period: About 2-3 months
Clinical syndromes:
Risk for development of chronic: unlikely: age dependent-infants and children at greatest risk
Distinctions: Highly contagious with recent leveling/decline, VACCINE

Question 3

Hep C: mode of transmission, clinical syndromes, incubation periods, risk for development of chronic hepatitis, and distinctions related to epidemiology.

Answer 3

Transmission: Usually parenteral, perinatal, rare STI
Incubation period: About 7 weeks
Clinical syndromes: Chronic liver disease and cirrhosis
Risk for development of chronic: 75-85%
Distinctions: Not highly contagious; No vaccine; increasing

Question 4

Hep D: mode of transmission, clinical syndromes, incubation periods, risk for development of chronic hepatitis, and distinctions related to epidemiology.

Answer 4

Transmission: Usually parenteral, also perinatal and sexual
Incubation period: 21-49 days
Clinical syndromes: Requires HBV for replication/expression of its RNA; possible superinfection–>chronic liver disease, cirrhosis and liver failure
Risk for development of chronic: Low risk
Distinctions: recent leveling/decline

Question 5

Hep E: mode of transmission, clinical syndromes, incubation periods, risk for development of chronic hepatitis, and distinctions related to epidemiology.

Answer 5

Transmission: Fecal, oral
Incubation period: About 40 days
Clinical syndromes: Acute, self-limiting
Risk for development of chronic: None
Distinctions: Prevalent in developing world; high mortality rate for pregnant women

Question 6

Describe the immune response to viral infection

Answer 6

TLRs help recognize virus as non-self–>Type 1 interferon production triggered–>Inhibit viral replication, activate NK cells, enhances MHC I expression

Antibodies neutralize
Ab-dependent cell-mediated cytotoxicity
Complement activation

Question 7

Describe 4 mechanisms used by viruses to evade the immune system.

Answer 7

1) Frequent genetic mutation-antigenic shift
2) Specific mechanisms to evade host defenses- interferons, complement
3) Direct suppression of host immune system- down regulate MHC
4) Evade detection by remaining latent

Question 8

IgM anti-HAV: principle and diagnostic significance

Answer 8

IgM against Hep A virus; Screening

Question 9

Total anti-HAV: principle and diagnostic significance

Answer 9

All antibodies against Hep A virus; Screening

Question 10

HBsAg: principle and diagnostic significance

Answer 10

Hep B surface antigen; Screening; Indicates active infection

Question 11

anti-HBs: principle and diagnostic significance

Answer 11

Antibody to hep B surface antigen; Screening; recovery/immunity from infection

Question 12

anti-HBc: principle and diagnostic significance

Answer 12

Antibody to Hep B core antigen ; previous or ongoing infection

Question 13

IgM anti-HBc: principle and diagnostic significance

Answer 13

IgM against Hep B core antigen; Screening; acute infection or recent infection

Question 14

HBeAg: principle and diagnostic significance

Answer 14

Hep B envelope antigen; virus is replicating/ high viral load

Question 15

anti-HBe: principle and diagnostic significance

Answer 15

Antibody against Hep B envelope; recovering from infection

Question 16

anti-HCV: principle and diagnostic significance

Answer 16

Antibody against Hep C; Screening

Question 17

HAV RNA: principle and diagnostic significance

Answer 17

Hep A RNA

Question 18

HBV DNA: principle and diagnostic significance

Answer 18

Hep B DNA

Question 19

HCV RNA: principle and diagnostic significance

Answer 19

Hep C RNA

Question 20

ALT: role in diagnosing hepatitis

Answer 20

alanine aminotransferase increases

Question 21

AST: role in diagnosing hepatitis

Answer 21

aspartate aminotransferase increases

Question 22

alkaline phosphatase: role in diagnosing hepatitis

Answer 22

ALP; increases

Question 23

bilirubin: role in diagnosing hepatitis

Answer 23

increases; product of blood cell breakdown

Question 24

total protein: role in diagnosing hepatitis

Answer 24

decreases

Question 25

serum albumin: role in diagnosing hepatitis

Answer 25

decreases

Question 26

protime: role in diagnosing hepatitis

Answer 26

increases ; its how fast you clot

Question 27

List non-serological laboratory tests used to diagnose hepatitis

Answer 27

Liver function tests: ALT, AST, ALP, Bilirubin | Synthetic function test: Total protein, Serum albumin, protime

Question 28

Describe the Epstein-Barr virus, the clinical syndromes it causes, and how it is transmitted.

Answer 28

DNA virus, spread though body fluids, infects epithelial cells of oropharynx and B cells; causes infectious mon (IM) and lymphoproliferative disorders and malignancies in immunocompromised patients

Question 29

Define heterophile antibody and correlate the heterophile antibody with its diagnostic significance.

Answer 29

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Question 30

heterophile antibody/ monospot: principle of laboratory tests for Epstein-Barr infection and describe their clinical utility and limitations

Answer 30

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Question 31

anti-VCA IgG/IgM: principle of laboratory tests for Epstein-Barr infection and describe their clinical utility and limitations

Answer 31

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Question 32

anti-EA: principle of laboratory tests for Epstein-Barr infection and describe their clinical utility and limitations

Answer 32

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Question 33

EBNA: principle of laboratory tests for Epstein-Barr infection and describe their clinical utility and limitations

Answer 33

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Question 34

Correlate typical clinical syndromes for EBV infection and lab findings with host factors including patient age, immune status, and disease progression.

Answer 34

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