Week 4: Pathogenesis, Infection, Antibiotics

Question 1

any organism capable of producing disease

Answer 1

pathogen

Question 2

what makes pathogens pathogenic?

Answer 2

• transmittable
• stick on host
• invade host
• toxic (endotoxin/exotoxin)

Question 3

transmission between mother and fetus/infant (between generations)

Answer 3

vertical transmission

Question 4

transmission within a generation

Answer 4

horizontal transmission (can be animal-person, person-person, fomite-person)

Question 5

transmission events that occur in a clinical setting

Answer 5

nosocomial

Question 6

three portals of entry

Answer 6

ingestion, inhalation, inoculation

Question 7

lipolysaccharide (LPS) molecules released from membranes of gram (-) bacteria cells

Answer 7

endotoxin

Question 8

toxin made by proteins of certain strains of gram (-) and gram (+)

Answer 8

exotoxin

Question 9

endotoxins cause death at ___ doses

Answer 9

high

Question 10

exotoxins cause disease at ___ doses

Answer 10

low

Question 11

a measurement of how likely a pathogen is to cause disease

Answer 11

virulence

Question 12

virulence based off of…

Answer 12

invasiveness, toxigenic potential

Question 13

virulence quantified as…

Answer 13

infectious dose 50 (ID50), lethal dose 50 (LD50)

Question 14

period of time between when a host is exposed to the pathogen and when the host begins to have symptoms of illness

Answer 14

incubation period

Question 15

stage when the host will have non-specific symptoms

Answer 15

prodromal period

Question 16

stage in which characteristic symptoms of disease present

Answer 16

acute phase

Question 17

stage in which symptoms of disease go away

Answer 17

recovery stage

Question 18

subclinical infections examples

Answer 18

asymptomatic, chronic carriers, latency

Question 19

Koch’s postulate 1 of 4

Answer 19

1. suspected causative agent must be absent from all healthy organisms but diseased one

Question 20

Koch’s postulate 2 of 4

Answer 20

2. causative agent must be isolated from diseased organisms and grown in pure culture

Question 21

Koch’s postulate 3 of 4

Answer 21

3. the cultured agent must cause the same disease when inoculated into healthy, susceptible organism

Question 22

Koch’s postulate 4 of 4

Answer 22

4. the same causative agent must then be re-isolated from the inoculated diseased organism

Question 23

“best guess” approach, most frequently used, know the disease/pathogen/usual sensitivity

Answer 23

empirical selection of antibiotic

Question 24

evaluate the pathogen, culture/sensitivity

Answer 24

rational selection of antibiotic

Question 25

term for killing bacteria

Answer 25

bactericidal

Question 26

term for slowing growth of bacteria

Answer 26

bacteriostatic

Question 27

B-lactam works by binding ____ that generates _______ in cell wall

Answer 27

transpeptidase, cross-links

Question 28

B-lactam antibiotic examples

Answer 28

amoxicillin/ampicillin, isozazolyl penicillins

Question 29

compound that improves B-lactam drugs but does not work on its own

Answer 29

clavulanic acid

Question 30

bacterial ribosome is different than ____ ribosome, so it can be used as a ___ of antibiotics (to block bacterial protein)

Answer 30

eukaryotic, target

Question 31

bacterial ribosome types of antibiotics

Answer 31

- macrolides - lincosamides - tetracyclins/glycycylines

Question 32

how do bacteria become resistant to antibiotics?

Answer 32

- natural resistance - mutation - acquired resistance

Question 33

how can a bacteria defeat an antibiotic?

Answer 33

- digest - alter - avoid - secrete