FA aminoglycosides+polymyxin

Question 1

Naujieji aminoglikozidai?

Answer 1

Gentamicinas, Amikacinas, Tobramicinas

Question 2

Senieji aminoglikozidai?

Answer 2

Neomicinas, Streptomicinas

Question 3

Kuri AMG i/v arba i/m?

Answer 3

IV or IM gentamicin
IV or IM amikacin
IV or IM tobramycin
IV or IM streptomycin

Question 4

kuris per os?

Answer 4

neomycin

Question 5

AMG cidal ir static?

Answer 5

cidal

Question 6

what inhibits AMG?

Answer 6

Bind to 30S subunit of the bacterial ribosome → IRREVERSIBLE inhibition of initiation complex → inhibition of bacterial protein synthesis → cell death (bactericidal effect)

Question 7

AMG leads to misreading of what?

Answer 7

Misreading of mRNA

Question 8

AMG blocks what process?

Answer 8

translocation.

Blockage of translocation: Depending on the aminoglycoside, translocation or the formation of the initiation complex is either inhibited or results in codon misreading.

Question 9

AMG synergistic works with what?

Answer 9

with beta-lactam antibiotics

Question 10

AMG CNS penetration?

Answer 10

poor

Question 11

AMG route of elimination?

Answer 11

renal (via glomerular filtration)

Question 12

what substance is required for AMG?

Answer 12

required O2 for uptake. therefore ineffective against anaerobes

Question 13

AMG coverage?

Answer 13

Severe gram-negative rod infections

Question 14

kodel AMG yra injekciniai?

Answer 14

nes bloga reabsorbcija is vt

Question 15

AMG are not effective against what?

Answer 15

Not effective against anaerobes (aminoglycosides require oxygen to be absorbed by cells)

Question 16

neomycin use?

Answer 16

Neomycin, which is not absorbed systemically, is administered orally to prepare the gut for bowel surgery.

Question 17

streptomycin use?

Answer 17

Streptomycin is used as a second-line treatment for Mycobacterium tuberculosis and M. avium-intracellulare

Question 18

4 groups of AMG adverse?

Answer 18

Nephrotoxicity

Ototoxicity and vestibulotoxicity (risk of ototoxicity is higher when used concurrently with loop diuretics) resulting in: Tinnitus, Ataxia, Vertigo

Neuromuscular blockade

Teratogenicity

Question 19

absolute contraindication for AMG?

Answer 19

Myasthenia gravis
Botulism
Pregnancy
Cautious use in patients with renal dysfunction

Question 20

AMG resistance?

Answer 20

Mechanisms of resistance: inactivation via acetylation, phosphorylation, and/or adenylation by secreted bacterial transferase enzymes

Question 21

Polymyxin agents?

Answer 21

polymyxin E (colistin) and polymyxin B

Question 22

administration of polymyxins?

Answer 22

i/v or i/m

Question 23

Polymyxins charge?

Answer 23

CATIONS

Question 24

BBB penetration of polymyxins?

Answer 24

poor

Question 25

polymyxin mechanism?

Answer 25

A cationic detergent (polypeptides) molecule that binds to phospholipids of the cytoplasmic membrane of gram-negative bacteria → increased membrane permeability→ leakage of cell contents → cell death (bactericidal effect)

Question 26

polymyxin cidal or static?

Answer 26

cidal

Question 27

polymyxins bind what?

Answer 27

Binds to and inactivates endotoxins (Colistin binds to the lipopolysaccharide on the cell membrane (i.e., endotoxin), thereby neutralizing LPS.)

Question 28

polymyxins general use?

Answer 28

severe infections caused by multidrug-resistant gram-negative bacteria

Question 29

polymyxins agains gram negative?

Answer 29

Effective only against gram-negative bacteria including P. aeruginosa, K. pneumoniae, E. coli, Acinetobacter baumannii, and Enterobacteriaceae spp.

Question 30

polymyxins agains gram positive?

Answer 30

not effective

Question 31

triple a/b for skin infections including polymyxins?

Answer 31

Topical antibiotics: triple antibiotic ointment (bacitracin, neomycin, and polymyxin B) for superficial skin infections

Question 32

Oral polymyxin B may be used to disinfect the bowel to prevent ICU infections

Answer 32

.

Question 33

adverse effect? polymyxins

Answer 33

Nephrotoxicity Neurotoxicity (e.g., paresthesias, weakness, speech disorders, neuromuscular blockage) Urticaria, eosinophilia, and/or anaphylactoid reactions Respiratory failure

Question 34

polymyxins route of elimination?

Answer 34

mainly renal

Question 35

contraindications of polymyxins?

Answer 35

Hypersensitivity to polymyxins Cautious use in patients with renal dysfunction