MICRO - Bacteria - Protein synthesis inhibitors

Question 1

Linezolid family name

Answer 1

Oxazolidinones

Question 2

Linezolid MOA

Answer 2

Binds 50s, prevents initiation complex formation

Question 3

Linezolid clinical use

Answer 3

MRSA, VRE

Question 4

Linezolid toxicity

Answer 4

Bone marrow suppression, peripheral neuropathy, serotonin syndrome

Question 5

Linezolid mechanism of resistance

Answer 5

POINT mutatoin in ribosomal RNA

Question 6

Aminoglycosides: name them

Answer 6

Gentamycin, Neomycin, Amikacin, Tobramycin, Streptomycin

Question 7

Aminoglycosides MOA

Answer 7

Binds 30s to inhibit initiation complex formation; causes mRNA misreading; blocks translocation.

Needs O2 for uptake

Question 8

Aminoglycosides clinical use

Answer 8

Aerobic gram negative rods.

Question 9

Aminoglycosides synergistic with:

Answer 9

beta-lactam antibiotics

Question 10

Aminoglycosides toxicity

Answer 10

Neuromuscular blockade, nephrotoxicity, ototoxicity (increase with loops), teratogen

Question 11

Aminoglycosides resistance:

Answer 11

Bacterial transferase enzymes inactivate the drug by: methylation, acetylation, adenylation

Question 12

Chloramphenicol MOA:

Answer 12

bind peptidyl transferase on 50s (inhibiting peptide bond formation)

Question 13

Chloramphenicol use:

Answer 13

meningitis and RMSF in pregnancy

Question 14

Chloramphenicol toxicity:

Answer 14

aplastic anemia, anemia, grey baby (via low UDP-GT)

Question 15

Chloramphenicol resistance

Answer 15

PLASMID-encoded acetyltransferase inactivates it

Question 16

Clindamycin MOA

Answer 16

binds 50s blocking translocation

Question 17

Clindamycin use

Answer 17

Anaerobic above the diaphragm and GAS

Question 18

Clindamycin toxicity

Answer 18

C. diff

Question 19

Macrolides: name them

Answer 19

Arithromycin, clarithromycin, erythromycin

Question 20

Macrolides MOA

Answer 20

Binds 23s of 50s preventing translocation

Question 21

Macrolides use

Answer 21

Atypical pneumonias, chlamydia, strep in patients allergic to penicillin, pertussis

Question 22

Macrolides toxicity

Answer 22

MACRO: motilin, arythmyas, cholestatic hepatitis, rash, eosinophilia. Increase theophylline (bronchodilator, but cardiotoxic and neurotoxic) and anticoagulants (bleeding)

Question 23

Macrolides resistance:

Answer 23

methylation of 23S

Question 24

Tetracyclins: name them

Answer 24

Tetracyclin, doxycyclin, minocyclin

Question 25

Tetracyclins use

Answer 25

lyme, RMSF, chlamydia, m.pneumonia, acne

Question 26

Tetracyclins toxicity

Answer 26

deposit in teeth (discolouration) and bones (inhibit growth) - contraindicated in kids and pregnancy. photosensitivity.

Question 27

Tetracyclins MOA

Answer 27

Prevent t-RNA binding. Bound by divalent cations so no milk, antacids, iron.

Question 28

Tetracyclins resistance:

Answer 28

decrease uptake or increased efflux via PLASMID-encoded pumps