Aminoglycoside

Question 1

AG

a. accumulate in renal failure
b. inhibit protein synthesis
c. effective against g-ve infx
d. all

Answer 1

d. all

Question 2

erythromycin is

a. cidal in axn
b. cidal in high conc
c. static in axn

Answer 2

b. cidal in high conc

Question 3

True about AG except

a. bacteriostatic
b. distributed only extracellularly
c. excreted unchanged in urine
d. teratogenic

Answer 3

a. bacteriostatic

Question 4

Common A/E of AG

Answer 4

ototoxicity and nephrotoxicity

Question 5

Aminoglycosides are poorly absorbed from the gut and must therefore be delivered via parenteral routes. T/F

Answer 5

T. aminoglycosides are poorly absorbed from the gut because they are highly polar molecules. Most are administered via the IV or IM route though some drugs – such as tobramycin – can also be administered via the inhalational route, too, as can, therefore, be used in the treatment of cystic fibrosis.

Question 6

Aminoglycosides lack activity against streptococci. T/F

Answer 6

T
Aminoglycosides lack activity against streptococci and anaerobes, so they should be combined with penicillin and/or metronidazole when the organism is unknown.

Question 7

Which aminoglycoside is most commonly used in the treatment of cystic fibrosis patients infected with Pseudomonas aeruginosa?
Amikacin
Streptomycin
Tobramycin
Gentamicin

Answer 7

Tobramycin

may be delivered via the inhalational route, and is therefore frequently deployed in cystic fibrosis patients infected with Pseudomonas aeruginosa.

Question 8

Aminoglycosides are most effective against which kind of microorganism?
Aerobic gram-negative bacteria
Anaerobic gram-negative bacteria
Aerobic gram-positive bacteria
Anaerobic gram-positive bacteria

Answer 8

Aminoglycosides are primarily effective against aerobic gram-negative bacteria such as Pseudomonas, Acinetobacter and Enterobacter. Aminoglycosides enter bacterial cells through an oxygen-dependent transport system. Therefore, it’s imperative that the Gram-negative bacteria are aerobic.

Question 9

Aminoglycosides work by irreversibly binding to the 30 ribosomal subunit. T/F

Answer 9

T

aminoglycosides work through irreversible inhibition of the 30S ribosomal subunit – inhibiting protein synthesis.

Question 10

Which of the following drugs is NOT an aminoglycoside?
Streptomycin
Neomycin
Amikacin
Azithromycin

Answer 10

Azithromycin belongs to the macrolide class of drugs. Streptomycin, neomycin and amikacin are all examples of aminoglycosides.

Question 11

Which of the following statements about aminoglycosides is false?
They have short half-lives
They are bactericidal
They exacerbate weakness in myasthenia gravis patients
None of the Above

Answer 11

None of the Above

Aminoglycosides have short half-lives: usually between 1 and 4 hours. They have a bactericidal effect – actively killing aerobic Gram-negative organisms. Furthermore, aminoglycosides can exacerbate weakness in patients with myasthenia gravis.

Question 12

AG are derived from which species?

a. streptomyces
b. micromonospora
c. A n B

Answer 12

c. A n B

Question 13

AG effective against

a. klebsiella
b. pseudomonas
c. enterobacter
d. all

Answer 13

d. all

Question 14

risk factor for AG induced neuromuscular paralysis

a. parkinson
b. use of diazepam
c. myasthenia gravis
d. asthma

Answer 14

c. myasthenia gravis

One of A/E is Enhance neuromuscular blocker activity

Question 15

S/E of topically applied neomycin

a. contact dermatitis
b. nephrotoxicity
c. ototoxicity
d. all

Answer 15

a. contact dermatitis

Question 16

AG used for TB treatment?

Answer 16

Streptomycin

Question 17

Topical use:
  neomycin
    penicillin
    kanamycin (Kantrex)
  streptomycin

Answer 17

neomycin

Question 18

route of administration: gentamicin (Garamycin)
   oral
  parenteral
    both
   neither

Answer 18

parenteral

Question 19

Patients with impaired renal function may suffer toxicity due to high tissue concentrations:
    streptomycin
    gentamicin (Garamycin)
  both
    neither

Answer 19

both

Question 20

Neuromuscular blockade at high dosages:
 amikacin (Amikin)
    penicillin G
    amphotericin B (Fungizone, Amphotec) been
  cefotaxime (Claforan)

Answer 20

amikacin (Amikin)

Question 21

Gentamicin (Garamycin) should NOT be used:
to treat sepsis caused by gram-negative bacteria such as Pseudomonas.
in combination with Penicillin G for endocarditis due to viridans streptococci
as a single agent to treat staphylococcal infections.
in combination with cephalosporin in immunocompromised patients.

Answer 21

as a single agent to treat staphylococcal infections.

Question 22

Reason(s) that favor combination of an aminoglycoside with a beta-lactam antibiotic:
advantage in extending coverage to potentially present gram-positive pathogens
drug classes are synergistic
both
neither

Answer 22

both

Question 23

Aminoglycosides
   time-dependent killing
  concentration dependent killing
   both
  neither

Answer 23

concentration dependent killing