Microbiology-Cases:53,54,55-Hepatitis

Front 1

a 23 year old man presented to ED with fever, jaundice, dark yellow urine pale colored stools and said the sight of food made him nauseated . he denied a history of IV drug use and had no sexual contact for the previous 2 months. five days ago he attended a family reunion. what type of virus is he infected with, DNA or RNA?

Back 1

RNA

Front 2

a 23 year old man presented to ED with fever, jaundice, dark yellow urine pale colored stools and said the sight of food made him nauseated . he denied a history of IV drug use and had no sexual contact for the previous 2 months. five days ago he attended a family reunion. how did he contract this virus?

Back 2

fecal oral

Front 3

a 23 year old man presented to ED with fever, jaundice, dark yellow urine pale colored stools and said the sight of food made him nauseated . he denied a history of IV drug use and had no sexual contact for the previous 2 months. five days ago he attended a family reunion. what is this virus?

Back 3

hep A

Front 4

a 23 year old man presented to ED with fever, jaundice, dark yellow urine pale colored stools and said the sight of food made him nauseated . he denied a history of IV drug use and had no sexual contact for the previous 2 months. five days ago he attended a family reunion.what is teh incubation period for hep A?

Back 4

30 days with range from 10 to 50 days.- mean of 30 is shorter than other viral hepatitis viruses

Front 5

can you tell the difference between hep A hepatitis and all the other viral hepatitis's microscopically?

Back 5

no, they are indistinguishable

Front 6

what is the pathogenesis of hep A infection?

Back 6

it is associated with a pattern of injury to and destruction of hepatocytes, a result of the host immunologic resposne to teh virus, as HAV specific cytotoxic T cells destroy virus infected hepatocytes

Front 7

what antibody is presetn 5 to 10 days before the onset of symptoms of HAV?

Back 7

IgM HAV ab

Front 8

do you get chronic infection with hep A?

Back 8

no

Front 9

do you get a carrier state with hep A?

Back 9

no

Front 10

passive immunization with immunoglobulin given less than 2 weeks after exposure can prevent 80 to 90% of cases of infection with this virus?

Back 10

hep A

Front 11

what type of vaccine is available for hep A?

Back 11

killed vaccine

Front 12

in hepatitis both ALT and AST are elevated above this value?

Back 12

> 500 IU/L

Front 13

in the major infectious causes of hepatitis are hep viruses A, B and C the elevation of ___ is more pronounced than ___

Back 13

ALT elevation is more pronounced than AST

Front 14

how is alcoholic liver disease different from viral hepatitis with respect to ALT and AST?

Back 14

ALT and AST levels do not usually go above 500 IU/L, and AST is higher than ALT

Front 15

drug induced hepatitis is not uncommon and is often associated with very high levels of this int he blood?

Back 15

transaminases

Front 16

what would you see in liver enzymes in gallstone hepatitis?

Back 16

no marked increase in liver enzymes

Front 17

infection with these two viruses (not the hep's ) can caues elevated liver enzymes, but no significant jaundice?

Back 17

CMV and EBV

Front 18

which hep virus can be transmitted through shellfish?

Back 18

hep A

Front 19

a 27 year old woman is seen int eh cinic for fever, and eyes that turned yellow and she had developed generalized itching, what is this itching caused by?

Back 19

bile pigments in the skin- called pruritis

Front 20

a 27 year old woman is seen int eh cinic for fever, and eyes that turned yellow and she had developed generalized itching, she admitted to using IV drugs and she frequently shares needles with friends. what hep infeciton is likely?

Back 20

hep B

Front 21

in the IV drug user case, what type of virus RNA or DNA is the infectious agent causing her symptoms?

Back 21

DNA

Front 22

describe hep A?

Back 22

has a icosahedral capsid without a lipid envelope, resistant to heat, and stable in the environment, also it is a RNA virus

Front 23

describe hep B virus?

Back 23

double shelled DNA virus, circular genome, the viremic patient's blood may present three different particles under electron microscopy, the larger rounded bodies seen are full assembly infectious virus particles with a lipid envelop. the two smaller particles are a spherical nucleocapsid core, and tubular or filamentous particles of surface proteins HBsAg.

Front 24

what is the primary component of teh hep B vaccine?

Back 24

HBsAg

Front 25

what does HBsAg produce in the host?

Back 25

a protective neutralizing antibody

Front 26

what are the hep B diagnostic markers?

Back 26

HBsAg, HBcAg, and HBeAg and the specific antibodies

Front 27

how is heb B transmitted?

Back 27

IV drug use, sexual contact, or by perinatal (maternal -->neonatal; ie vertical tranmission)

Front 28

in the US what is the most common route of hep B tranmission?

Back 28

sexual contact- either homosexual or heterosexual

Front 29

what is responsible for the clinical manifestations of hep B infection?

Back 29

virus specific cytotoxic T lymphocytes, are responsible for the meanifestations and eventual resolution

Front 30

what is the first serologic marker to appear in heb B infection?

Back 30

HBsAg- can be detected as early as 1 or 2 weeks and as late as 11 to 12 weeks

Front 31

in persons who recover form Hep B this marker is no longer present in the blood after 3 months?

Back 31

HBsAg

Front 32

in what period do Anti-HBs become detectable?

Back 32

during convalesence period after disappearance of HBsAg in pts who do not progress to chronic

Front 33

what antibody is detectable at the time of clinical onset and declines to subdetectable levels within 6 months?

Back 33

IgM class antibody to Hep B core antigen

Front 34

how can diagnosis of acute HBV be made?

Back 34

on basis of detection fo IgM HbcAb

Front 35

what is hep B's strategy?

Back 35

hide and infiltrate - copis of HBV genome integrate into teh hepatocyte chromatin and remain latent-->chronicity

Front 36

what things remain persistently detectable in a persons blood with chronic HBV infection?

Back 36

HBsAg and IgG HbcAg

Front 37

presence of this for 6 months or more is indicative of chronic HBV infection?

Back 37

HbsAg

Front 38

what would it indicate if you got a negaitve test for IgM HBcAb but positive HBsAg in a single serum specimen?

Back 38

chronic HBV infection

Front 39

the presence of these things remain for a lifetime with a person with chronic HBV infeciton?

Back 39

HBsAg and IgG HBcAg

Front 40

a symptomatic HBsAg carrying patient is higly infectious and there is a significantly high level of this in the serum?

Back 40

HBeAg

Front 41

what are risk factors for hepatocellualr carcinoma?

Back 41

older age at onset of HBV infection, alcohol induced liver damage, down syndrome, chronic lymphocytic leukemia, and immunodeficiency

Front 42

what is teh treatment for acute HepB?

Back 42

no specific treatment, only supportive care

Front 43

what is the treatmetn for chronic HepB?

Back 43

interferon alpha, lamivudine or adefovir

Front 44

a 48 year old man presents with elevated transaminases and no symptoms, he denied IV drug use but did receive a blood transfusion 25 years before. describe a possible concern given this man's history?

Back 44

Hep C infection

Front 45

describe hep C?

Back 45

from family flaviviridae, enveloped with icosahedral capsid, containing single stranded, polyadenylated, positive sense RNA genome

Front 46

what is teh only habitat for HCV?

Back 46

humans

Front 47

what are the ways a person could be exposed to Hep C int eh US?

Back 47

parenteral (percutaneous eg IV drug use, needle sticks, tattooing, transfusions or organs transplantation from infected donor efore routne testing of blood products began), permucosal (sex with infected partner) and perinatal (vertical transmission)

Front 48

what are most infections of hep C due ot?

Back 48

illegal injection drug use

Front 49

what is the incubation period for hep C?

Back 49

14 to 180 days (avg 6 to 7 weeks)

Front 50

what other hep does Hep C resemble in course and severity?

Back 50

hep B

Front 51

do persons with newly acquired (acute) HCV infection have symptoms?

Back 51

no (80% have no signs or symptoms)

Front 52

what is teh most characteristic finding in blood work for an HCV infected person?

Back 52

elevation of ALT (this precedes anti HCV seroconversion)

Front 53

after acute HCV infection 15 to 25% of people progress to this?

Back 53

resolution of symptoms with no sequelae, as defined by sustained presence of HCV RNA. in some persons ALT levels normalize suggesting full recovery

Front 54

but frequently, in 75 to 80% of HCV infected persons, the normalization of serum ALT is followed by this?

Back 54

ALT elevations that indicate progresion to chronic disease

Front 55

a chronc carrier state is common with HCV infection it occurs in > than ___% of people

Back 55

50%

Front 56

what do tests for HCV measure?

Back 56

HCVAb (include enzyme immunoassays EIAs and a supplemental recominant immunoblot assay RIBA)

Front 57

can also detect HCV with this method?

Back 57

detecting HCV RNA with gene amplificaiton techniques

Front 58

what drugs are used to treat chronci HCV infeciton?

Back 58

interferon and ribavirin- combo treatment with these two is treatment of choic and provides best results

Front 59

hep A is a ___virus

Back 59

enterovirus (meaning it enters the body through the GI tract)

Front 60

what age group is most frequently infected with Hep A?

Back 60

children

Front 61

when does hep A virus appear in the feces?

Back 61

2 weeks prior to symptoms, so quarantine of patients is ineffective

Front 62

where does hep A replicate?

Back 62

in GI tract

Front 63

what is the initial antibody with a hep A infection?

Back 63

IgM

Front 64

IgM appearance in hep A is followed 1-3 weeks later by production of this antibody?

Back 64

IgG- which provides lifelong protection

Front 65

detection of this is the most important test for hep A infection?

Back 65

detection of IgM antibody

Front 66

what are the two types of vaccines for hep A?

Back 66

active immunization containing inactivated HAV, and passive immunizaiton with immune serum globulin prior to inection or within 14 days after exposure can prevent and mitigate teh disease

Front 67

Hep B virus is also known as this?

Back 67

dane particle

Front 68

which hep is a defective virus?

Back 68

Hep D

Front 69

which hep virus has DNA polymerase?

Back 69

hep B

Front 70

which hep viruses have HBsAg in the envelope?

Back 70

HBV and HDV

Front 71

which hep infections have a chronic carrier state?

Back 71

hep B, C and D

Front 72

what is the lab test to detect hep D?

Back 72

Ab to delta Ag

Front 73

what is the lab test for hep E?

Back 73

none

Front 74

for which hep viruses is there a vaccine?

Back 74

hep A, and B

Front 75

in which hep infections is immunoglobulins useful?

Back 75

hep A and B

Front 76

which hep viruses can be transmitted vir a blood and sexual contact?

Back 76

hep B, C and D

Front 77

which hep infeciton can be transmitted fecal oral?

Back 77

hep A and E

Front 78

the HBV vaccine is the first vaccine to do this?

Back 78

prevent a human cancer

Front 79

this disease can occur in hep B carriers?

Back 79

hepatocelluarl carcinomas (occur at a high rate)

Front 80

what does HBeAg in a person's blood indicate?

Back 80

high likelihood of transmissibility

Front 81

what is teh most prevalent blood borne pathogen in US?

Back 81

hep C

Front 82

how does the chronci carriage of HCV compare to that of HBV?

Back 82

incidence of chronic carrier state is much higher with HCV

Front 83

how does acute infection with HCV compare ot HBV?

Back 83

HCV is much milder

Front 84

is the test for HEV antibody readily availabe?

Back 84

no so the diagnosis is typically made by excluding HAV and other causes

Front 85

HDV can only replicate in this situation?

Back 85

with help of HBV