Antimicrobials I

Question 1

to be an effective beta lactam drugs must:

Answer 1

1. evade bacterial defenses( amidase, lactamase
2. Penetrate the outer cell layers to inner cytoplasmic membrane
3. Keep its beta lactam ring intact
4. Blind to the traspeptidase (PCN-binding protein, PBP)

Question 2

Transpeptidase enzymes crosslink

Answer 2

adjacent glycan chains by removing
the terminal D-alanine residue from one of the peptidoglycan
precursors.

Question 3

org PNC

Answer 3

PNC G

Question 4

β-lactam antibiotics bind to the active site of the PBP to ______ transpeptidation, the terminal step in new petidoglycan synthesis.

Answer 4

prevent

Question 5

Penicillin G (only true naturally occurring penicillin) is highly active against

Answer 5

sensitive strains of Gram (+) cocci

Question 6

Ampicillin, amoxicillin:

o  better Gram (-) coverage than

Answer 6

either Pen G or Pen V

Question 7

Penicillin V are less active than

Answer 7

pnc g

Question 8

Allergy to Amoxicillin (non-β-lactams )are given

Answer 8

Clindamycin
Azithromycin
Clarithromycin

Question 9

Alternative in case of non-anaphylatic allergy

Answer 9

Cephalexin

Question 10

naf for

Answer 10

staph

Question 11

Immediate/acute onset

Answer 11

reactions within 30 minutes (anaphylaxis); IgE

mediated – life-threatening

Question 12

Accelerated onset

Answer 12

arise 30 min-48 h after admin.; urtucaria, pruitis, wheezing, local inflammatory response (generally not-life threatening)

Question 13

Delayed onset

Answer 13

reactions that take longer than 2 days to develop. 80-90% of penicillin reactions are of this type (i.e., basic rashes, generally mild)