Bacteriology Quiz 3

Front 1

what kind of bacteria is streptococcus pneumoniae

Back 1

gram positive diplocci (lancet shaped with points outward)

Front 2

what kind of hemolytic morphology is step pneumonae

Back 2

alpha-hemolytic (yields a cloudy green zone that contains intact red cells with chemically altered green pigment)

Front 3

the most used test to make the distinction between strep viridans and strep pneumoniae demostrates pneumoniae's sensitivity to

Back 3

optochin

Front 4

nearly 100 types of pneumococci are identified by their antigenically distinct

Back 4

capsules

Front 5

the capsule of strep pneu can be identified using what reaction

Back 5

quellung reaction (specific Ab reacts with the pneumococcal capsule, the capsule swells enough to allow the difference to be seen microscopically.

Front 6

pneumococci are common inhabitants of the

Back 6

throat

Front 7

the most frequent form of bacterial pneumonia

Back 7

Pneumococcal penumonia

Front 8

why is the lower respiratory tract not infected more by pneumococcal infection

Back 8

1. aspiration of mucus is rare
2. when it does happen the cilia of the respiratory epithelium are always driving a stream of mucus up the respiratory tract
3. alveolar macrophages can phagocytoze a limited number of bacteria

Front 9

what happens to the pneumococci when they are phagocytosed

Back 9

they are killed (they only grow extracellularly)

Front 10

what is the key component of pathogenesis of strep pneumoniae

Back 10

capsule

Front 11

"surface phatogocytosis"

Back 11

in the absence of antibody, macrophages succeed in phagocytosis only when they can "trap" the organisms against a surface

Front 12

in the alveoli what might make "surface phagocytosis" difficult

Back 12

edema - works better with "dry"alveolus

Front 13

how does consolidation and lobar pneumonia develop in a strep pneumoniae infection?

Back 13

bacteria escape surface phagocytosis. multiply. serous fluid enters alveoli. hinders surface phagocytosis. PMNs enter infected alveoli producing consolidation and this proceeds throughout lobe

Front 14

what two things halt the process of consolidation and lobar pneumonia development in strep pneum

Back 14

antibody and antibiotics

Front 15

in strep pneumonaie the sudden onste of shaking chills and prolonged high fever with severe pleuitic pain and cough is accompanied by what colared sputum

Back 15

rusty - blood tinged

Front 16

will leukocyte numbers increase or decrease with infection of strep pneu

Back 16

increase (leukocytosis)

Front 17

a dramatic drop of fever and sense of well being woudl be due to

Back 17

onset of immune response (even in untreated cases)

Front 18

what is one critical factor in natural recovery from strep pneumo and in immunity

Back 18

opsonizing antibody to type specific polysaccharide capsule (those pts with defect in humoral immunity are at much higher risk)

Front 19

what organ plays a major role in combating bacteremia

Back 19

spleen. those pts with sickle cell anemia or who have been splenectomized are at high risk

Front 20

why is sensitivity testing required for pneumococcal p.

Back 20

multiple antibiotic resistance (including penecillin) is frequent

Front 21

microscopic examination of what kind of culture helps diagnosis of strep pneu

Back 21

sputum - but does not determine type.

Front 22

in children pneumococci play a prominent role in what kind of infections

Back 22

middle ear and can cause severe or fatal meningitis

Front 23

The pneumococcal vaccine (first and second one) prevent what kind of pneumococcal infecation

Back 23

invasive (bacteremic disease) and prevents pneumococcal meningitis but does not protect against community aquired peumococcal pneumonia

Front 24

a small gram positive rod distanlty related to diphtheroids but beta hemolytic

Back 24

listeria monocytogenes

Front 25

listeria monocytogenes is found

Back 25

in soil and water as well as infected animals and humans

Front 26

how might a human become infected with listeria monocytogenes

Back 26

infected food (dairy?)

Front 27

why is listeria monocytogenes a potent food borne pathogen

Back 27

grows well in the refrigerator

Front 28

why are pregnant women more susceptible to listeriosis

Back 28

decline in cell-mediated immunity (immunosuppressed individuals are also at high risk)

Front 29

infection of pregnant woman by listeria moncytogenes can resut in? how might this differ in early term vs. late term

Back 29

bacteremia, and transplacental infection
early term: abortion, stillbirth
late term: newborn may die of early onset neonatal septicemia and meningitis

Front 30

adult infections with listeria monocytogenes include

Back 30

meningitis, septicemia, urethritis, and endocarditis

Front 31

how might a pregnant woman or immunized supressed individual avoid infection of listeria monocytogenes

Back 31

avoid raw milk and unprocessed soft cheese (brie, feta etc..)cottage cheese, cream cheese and yogurt are safe

Front 32

is listeria monocytogenes intracellular or extracellular pathogen

Back 32

facultative intracellular

Front 33

how does l. monocytogenes around into the cytoplasm of the cell

Back 33

polymerized host cell actin to to power its intracellular motility and gets from cell to cell w/o geoing through the extracellular medium

Front 34

anthrax is caused by

Back 34

bacillus anthracis

Front 35

what kind of bacteria is bacilus anthracis

Back 35

gram positive spre forming

Front 36

some of the pathology of bacillus anthracis is a result of anthrax exotoxin which require what to enter mammalian cell

Back 36

bacterial protein called the "protective antigen" because ab to this antigen protect against disease

Front 37

all three pathways for human infection by bacillus anthracis are aused by what and come from what

Back 37

caused by spores coming from animals

Front 38

in cutaneous antrax bacterial growth results in what

Back 38

painless vesicle with surrounding edema

Front 39

the lsion produced by cutaneous anthrax progresses to produce a black scab called

Back 39

ESCHAR

this is the least serious anthrax infection

Front 40

if untreated the cutaneous lesion caused by b. anthracis may lead to fatal

Back 40

bacteremia

Front 41

what is the most common and least serious presentation of anthrax

Back 41

cutaneous anthrax

Front 42

the rare intestinal anthrax results from

Back 42

ingestion spres usually in meat

Front 43

in inhalation anthrax the inhaled spores are phagocytosed by

Back 43

pulmonary macrophages

Front 44

where do the inhaled anthrax spores germinate and produce exotoxins

Back 44

regional lymph nodes

Front 45

an early sign of inhalation anthrax is

Back 45

enlargement of mediastinal lymph nodes

Front 46

is there a vaccine for anthrax

Back 46

yes - consists of B. anthracis proteins - used for at-risk populations such as veterinarians and troops threatened by biological warfare - it is effective and safe