Antimicrobial Therapy - Allman

Question 1

Bactericidal agent

Answer 1

penicillin, cephalosporin

Question 2

Bacteriostatic agent

Answer 2

sulfonamides

Question 3

Narrow Abx

Answer 3

Pen G, Nafcillin

Question 4

Broad Abx

Answer 4

Piperacillin/Tazobactam

Imipenem

Question 5

Synergy

Trimethoprim/sulfamethoxazole

Answer 5

sequential inhibition of folic acid synthesis

Question 6

Synergy

Penicillin/Aminoglycoside

Answer 6

Increased penetration of aminoglycoside as penicillin breaks down cell wall
- enterococcus
Different site for mechanism of action
- psudomonas

Question 7

Antagonism

Answer 7

Bacteriostatic on bactericidal

Question 8

Post antibiotic effect (PAE)

Answer 8

persistent effect of an antimicrobial on bacterial growth following brief exposure of organism to a drug

• Aminoglycoside and fluoroquinolones

Question 9

two parts of pharmacodynamics

Answer 9

Concentration and time dependent killing

Question 10

Concentration dependent killing

Answer 10

• peak concentration
• optimal when conc exceeds 10x MIC

Quinolones, Aminoglycoside (AMG)

Question 11

Time dependent killing

Answer 11

amnt of time [ ] stays above MIC (40-50%)

B-lactam Abx

Question 12

Inhibitors of Cell Wall synthesis

Answer 12

Penicillin/Cephalosporins/Carbapenems/Aztreonam
Vancomycin
Bacitracin
Cycloserine

Question 13

Penicillin/Cephalosporins/Carbapenems/Aztreonam

Answer 13

Prevents cross linking of peptidoglycan strands by inhibiting transpeptidases

Question 14

Vancomycin

Answer 14

inhibits peptidoglycan synthetase and polymerization of linear peptide

Question 15

Inhibitors of protein synthesis/structure

Answer 15

AMG 
Chloramphenicol
Erythromycin/clindamycin/lincomycin
Tetracyclines
Streptogramins/Linezolid

Question 16

AMG

Answer 16

inhibits 30 S ribosome

Causes misreading of mRNA

Question 17

Chloramphenicol

Answer 17

inhibits peptidyl transferase and peptide band formation

Question 18

Erythromycin/clindamycin/lincomycin

Answer 18

inhibits 50 S ribosome

Question 19

Tetracyclines

Answer 19

inhibits binding of aminoacyl tRNA to ribosome

30 S ribosome

Question 20

Streptogramins/Linezolid

Answer 20

23 S ribosome

Question 21

Interference with Cell Membrane function

Answer 21

Polymixin B, Colistin

Fungal: Azole and polyene antifungals

Question 22

Polymixin B, Colistin

Answer 22

Cationic detergent

Question 23

Interference with DNA/RNA synthesis

Answer 23

Rifampin

Fluoroquinolones

Question 24

Rifampin

Answer 24

inhibits DNA-dependent RNA polymerase

Question 25

Fluoroquinolones

Answer 25

Interferes with supercoiling of DNA by action on DNA gyrase (topoisomerase II)

Question 26

Inhibitors of Metabolism

Answer 26

Isoniazid, ethambutol | Sulfonamides, trimethoprim

Question 27

Isoniazid, ethambutol

Answer 27

Inhibits lipid synthesis

Question 28

Sulfonamides, trimethoprim

Answer 28

Prevents synthesis of folic acid

Question 29

Empiric therapy

Answer 29

Culture site before starting Abx | Gram stains - very informative for selection of empiric Abx

Question 30

Distribution of Meningitis

Answer 30

Penetration into CNS when meninges are inflammed vs uninflammed Ceftriaxone vs Unasyn

Question 31

Considerations for drug distribution

Answer 31

Urine concentration Bone penetration Lung Tissue penetration Skin and soft tissue concentration

Question 32

Example of concurrent medication inference with abx

Answer 32

Antacids with quinolones and tetracycline

Question 33

Examples of abx inference with concurrent agent

Answer 33

- Bactrim or erythromycin with warfarin - ciprofloxacin with theophylline - Linezolid with SSRIs

Question 34

microbial resistance results from

Answer 34

environmental exposure to Abx mutation adaptation gene transfer multiple resistance -- plasmids can develop during therapy or is intrinsic

Question 35

Mechanisms of Resistance

Answer 35

- Increased drug inactivating enzyme activity - Alter cell wall/membrane permeability - altered binding site/receptor of drug - drug efflux - increase endogenous metabolite

Question 36

Dose related toxicities for Imipenem Amphotericin Cefazolin

Answer 36

Imipenem - seizures Amphotericin - nephrotoxicity Cefazolin - Neutropenia (dose and duration)

Question 37

Idiosyncratic reaction for: chloramphenicol

Answer 37

aplastic anemia

Question 38

What should be used for Abscess?

Answer 38

``` Antibiotic therapy (not enough) Drainage of area ```

Question 39

Superinfection

Answer 39

alt normal flora from removal of inhibitory influences in the body - due to broad spectrum abx - enterobacteriaceae (PEK, SE) - Candida spp. - Clostridium difficile (Psuedomembranous colitis)

Question 40

Which abx gets inactivated by lung surfactant?

Answer 40

Daptomycin

Question 41

Where is the highest concentration of Abx found?

Answer 41

Urinary concentration