SELECTIVE TOXICITY

Question 1

How does abx have the ability to kill or suppress microbial pathogens w/o harming host??

Answer 1

selective toxicity

Question 2

What are 3 examples of selective toxicity?

Answer 2

1. Disruption of bacterial cell wall
2. Inhibit enzyme unique to bacteria
3. inhibit bacterial protein synthesis

Question 3

Narrow spectrum abx kills what type of bacteria?

Answer 3

G+ cocci and G+ bacilli
G- aerobes
Mycobacterium tuberculosis

Question 4

Abx that:
INHIBITS CELL WALL SYNTHESIS

Answer 4

PCN, cephalosporins, imipenem,
Vanco, caspofungin

Question 4

Broad spectrum abx kills what type of bacteria?

Answer 4

G+ cocci and G- bacilli

Question 5

abx that:
DISRUPTS CELL MEMBRANE

Answer 5

Amphotericin B, Daptomycin, Itraconazole

Question 6

BACTERIOSTATIC (halt) inhibitors of protein synthesis

Answer 6

Clindamycin, erythromycin, linezolid, tetracyclines (CELT)

Question 7

BACTERICIDAL (kills) inhibitors of protein synthesis

Answer 7

Aminoglycosides

Question 8

Rx that interferes with synthesis OR integrity of bacterial DNA and RNA

Answer 8

Fluoroquinolones, metronidazole, rifampin (FluMeR)

Question 9

Antimetabolites drugs

Answer 9

Flucytosine, sulfonamides, trimethoprim (FST)

Question 9

Drug level for minimal inhibitory concentration (MIC)

Answer 9

4-8x

Question 9

How do microbes become resistant?

Answer 9

1. decrease penetration to target site
2. alteration of target site
3. inactivate drug by bacterial enzyme

Question 9

Factors to consider when choosing abx

Answer 9

1. which bacteria?
2. pattern of resistance
3. organism susceptibility
4. achievable semen, tissue, or body fluid concentration
5. allergy
6. toxicity
7. formulation/ bioavail
8. adherence/ convenience
9. cost and formulation options

Question 9

Use of combination abx can result in what?

Answer 9

additive, potentiate or antagonistic effect

Question 10

What generation of cephalosporin is most commonly used for surgery prophylaxis ?

Answer 10

first gen (cefazolin)

Question 10

PCN is also known as______.

Answer 10

beta- lactam abx

Question 10

What is the MOA of PCN?

Answer 10

Disruption of cell wall synthesis by inhibiting transpeptidases and activation of autolysin

Question 10

The use of trimethoprim/sulfamethoxazole results in what effect?

Answer 10

potentiative

Question 11

PCN G and V are___ spectrum PCN (penicillinase sensitive)

Answer 11

narrow

Question 12

PCN G and V are useful for which microbes?

Answer 12

Streptococcus spp., N spp., many anaerobes, spirochetes, and others

Question 13

Nafcillin, oxacillin, and dicloxacillin are _____ spectrum PCN

Answer 13

narrow; penicillinase resistant

Question 14

Ampicillin and amoxicillin are ___ spectrum abx

Answer 14

broad spectrum

Question 14

What microbes do nafcillin, oxacillin, and dicloxacillin kill?

Answer 14

S. aureus

Question 15

Ampicillin and amoxicillin are effective against which microbes?

Answer 15

H. influenzaue, E. coli, P. mirabilis, enterococci, and N. gonorrhoeae

Question 15

______ is an extended-spectrum PCN.

Answer 15

Piperacillin