Pharm - Inhibitors Of Cell-Wall Synthesis

Question 0

What is the weakest bond in the lactam and what is special about it?

Answer 0

The bond between the nitrogen and the carbonyl group, which is the working site of B-lactamases!

Question 1

Which Cell-Wall synthesis inhibitor is not a lactam?

Answer 1

Vancomycin

Question 2

All lactams have 3 mechanisms of action..

Answer 2

1 Bind PBPs
2 Inhibit transpeptidation
3 Inhibit crosslinking

Question 3

All lactams can be disabled my 3 mechanisms of resistance..

Answer 3

1 Penicillinases
2 Structural change in PBPs (MRSA) - use vancomycin!
3 Change in porin structure

Question 4

On what spirochete is the the narrow spectrum Penicillin G and Penicillin V effective?

Answer 4

Treponema pallidum which causes syphilis.

Question 5

Two broadspectrum, betalactamase sensitive penicillins?

Answer 5

Amoxicillin and ampicillin are used against:
1 gram + cocci(not staph)
2 gram - E. coli, H. influenzae, H. pylori
3 Borrelia

Question 6

Clavulanic acid, sulbactam, tazobactam are …………

Answer 6

Clavulanic acid, sulbactam, tazobactam are beta-lactamase inhibitors

Question 7

Two penicillins that are eliminated largely in bile?

Answer 7

Nafcillin and oxacillin are more lipid soluble and are therefore excreted primarily in bile.

Question 8

Two penicillins where you will not have to adjust the dose in people with decreased renal function?

Answer 8

Nafcillin and Oxacillin - excreted in bile.

Question 9

What is Jarisch - Herxhermer reaction?

Answer 9

Treatment of syphilis with antibiotics that destroys the Treponema and releases it into the blood stream - causing systemic infection.

Question 10

Cephalosporin mechanism of action?

Answer 10

Like penicillins

Question 11

Two first generation cephalosporins? Area of use?

Answer 11

Cefazolin and cephalexin. Used in surgical prophylaxis because of their long half-life that can protect against entry of bacteria from skin.

Question 12

Second generation cephalosporin: first cephalosporin to cross the BBB?

Answer 12

Cefuroxime. Used in meningitis.

Question 13

Cephalosporins used in empirical management of sepsis and meningitis?

Answer 13

Third generation cephalosporins: esp. ceftriaxone.

Question 14

Third generation cephalosporin do not work against?

Answer 14

LAME

Listeria, Atypicals, MRSA & Enterococci

Question 15

To treat MRSA we use….

Answer 15

Vancomycin

Question 16

Two cephalosporins that are eliminated primarily through bile?

Answer 16

Cefoperazone and ceftriaxone.

Question 17

What to use in case of allergies to lactams?

Answer 17

macrolides or aztreonam(only gram neg rods - Pseudomonas)

Question 18

Most potent lactams?

Answer 18

Imipenem and meropenem

Question 19

What is the reason for the high potency of imipenem and meropenem?

Answer 19

Resistant to beta - lactamases.

Question 20

imipenem must be coadministered with ……….

Answer 20

cilastatin.

Question 21

What i Cilastatin?

Answer 21

A renal dehydropeptidase inhibitor.

Question 22

Aztreonam mechanism of action?

Answer 22

Same as cephalosporins and penicillins.

Question 23

We use aztreonam to treat against ………

Answer 23

gram negative rod ONLY

Question 24

Drug that have no cross - allergenicity with penicillins and cephalosporins?

Answer 24

Aztreonam - working against gram negative rods.

Question 25

Vancomyocin mechanism of action?

Answer 25

binding at D-ala-D-ala Muramyl pentapeptide that interferes with transpeptidatioin(elongation of peptidoglycan cell wall)

Question 26

Enterococci mechanism of resistance against vancomycin?

Answer 26

changing the terminal D-ala with a D-lactate, thereby removing the binding-target used by vancomycin.

Question 27

VRE and VRSA are?

Answer 27

Vancomycin Resistant Enterococcus & Vancomycin Resistant Staphylococcus Aureus.

Question 28

Two drugs used against VRE and VRSA?

Answer 28

Linezolid and Streptogranins

Question 29

Describe host determinants for choice of drug?

Answer 29

• history of drug reactions
• site of infection
• renal status
• hepatic status
• immune status
• pregnancy/lactation
• metabolic abnormalities

Question 30

Group of bacteria that are particularly suceptible to penicillins?

Answer 30

gram positives

Question 31

Common beta-lactamase producing organisms include..?

Answer 31

S. aureus, E. coli, Salmonella, Pseudomonas, N. gonnhore, Bacillus, Proteus, Bacteroides spp.

Question 32

nafcillin, oxacillin and clidoxacillin primary target?

Answer 32

S. aureus. NOT MRSA

Question 33

Name two anti-pseudomonal ab and their target organisms?

Answer 33

Ticarcillin/piperacillin kills pseudomonas, E. coli, Salmonella, Proteus, Enterobacter and Klebsiella.

Question 34

Amoxicillin + clavulanic acid =

Answer 34

Augmentin

Question 35

Clavulanic acid moa?

Answer 35

irreversible inhibitor of Beta-lactamases

Question 36

Hypersensitivity reactions are seen in how many patients?

Answer 36

10% is the answer to this question. 10 % is also the answer to how much I want to stay in the czytelnia at the present moment.

Question 37

Endocarditis prophylaxis is indicated in…….

Answer 37

• GI surgery
• Pulmonary surgery
• Major dental surgery
• Genitourinal surgery

Question 38

What drugs are used in prophylactic treatment of endocarditis?

Answer 38

amoxicillin and ampicillin. IF hypersensitive to penicillins use clindamycin or azithromycin.

Question 39

Describe the structure of sephalosporins

Answer 39

7-aminocephalosporic acid nucleus + B-lactam ring = BOOM!

Question 40

Cephalosporin mechanism of action?

Answer 40

same as penicillins

Question 41

General characteristics of 3rd and 4th generation cephalosporins?

Answer 41

• Parenteral administration
• B-lactamase resistant
• penetrates CNS

Question 42

The newer cephalosporins are increasingly effective against what?

Answer 42

penicillinases/B-lactamases

Question 43

Name a drug that decrease the secretion of cephalosporins

Answer 43

Probenecid

Question 44

3rd generation cephalosporins are increasingly effective against……

Answer 44

gram negs mahn! I be talkin’ bout dem gram negs

Question 45

Adverse effects cephalosporins?

Answer 45

• hypersensitivity
• disulfiram-like effects
• bleeding(vitamin K)
• nephrotoxicity
• Clostridium Difficile Colitis

Question 46

Important hypersensitivity association w/ azetreonam =

Answer 46

no cross-reaction with penicillins and cephalosporins

Question 47

3 most important carbapenems?

Answer 47

imirenem
meroprenem
azetreonam

Question 48

Imipenem + cilastatin =

Answer 48

Primaxin

Question 49

Cilastatin mechanism of action?

Answer 49

inhibitor of of renal dehydropeptidase I, which inactivates imipenem.

Question 50

Carbapenem target organisms?

Answer 50

• penicillinase producing Staph aureus
• E .coli
• Pseudomonas
• H. influenzae

Question 51

Vancomycin + aminoglycosides relationship =

Answer 51

• synergistic effect

- adverse effects include ototoxicity + nephrotoxicity

Question 52

Vancomycin and CNS?

Answer 52

penetrates only during inflammation

Question 53

Vancomycin and hypersensitivity?

Answer 53

• slow IV infusion - rapid infusion may precipitate anaphylaxis(red neck)
• no cross reaction with penicillins or cephalosporins

Question 54

Bacitracin general picture?

Answer 54

• gram positives
• inhibit reuse and synthesis on N-AM
• Only topical administration

Question 55

Cycloserine general picture?

Answer 55

• inhibit alanine racemase

- mycobacteria and gram negatives

Question 56

Skin lesions with large number of gram positive cocci. Administer?

Answer 56

Nafcillin - Nafcillin is resistant to penicillinases and is effective against most S. aureus and common streptococci