New antibiotics AB

Question 1

Linezolid - mechanism?

Answer 1

Inhibit protein synthesis (30s)

Bacteriostatic but acts like bactericidal

Question 2

Linezolid - activity? (3)

Answer 2

Gram positives
Mycobacterium
Nocardia

Question 3

Linezolid - ADR?

Answer 3

Lactic acidosis
Bone marrow suppression
Neuropathy - peripheral, optic
MAO-inhibition - serotonin syndrome

Question 4

Daptomycin - mechanism?

Answer 4

Cyclic lipopeptide
Binds to cell membrane
Bactericidal

Question 5

Daptomycin - activity?

Answer 5

Most gram positives (though inhibited by surfactant - don’t give in pneumonia)
Similar spectrum to glycopeptides

Question 6

Daptomycin - ADR?

Answer 6

Muscle pain

Elevated CK

Question 7

Tigecycline - mechanism?

Answer 7

Derivative of minocycline
Protein synthesis inhibitor
Essentially bacteriostatic

Question 8

Tigecycline - activity?

Answer 8

MRSA, VISA, VRE
Many gram negatives

NOT pseudomonas (efflux)

Question 9

Ceftaroline - activity?

Answer 9

MRSA

VISA but not great for VRE or ESBL

Question 10

Ceftaroline - indications?

Answer 10

Mainly for pneumonia, skin/soft tissue infection

Question 11

Colistin - mechanism?

Answer 11

Binds LPS and phospholipids in outer cell membrane

Bactericidal

Question 12

Colistin - activity?

Answer 12

Gram negatives including Pseudomonas, Enterobacter, Stenotrophomonas, Klebsiella, Salmonella

Question 13

Colistin - ADR?

Answer 13

Renal toxicity

Neurotoxicity

Question 14

Colistin - mechanism of resistance?

Answer 14

Via change in outer membrane

Question 15

Fosfomycin - activity?

Answer 15

Resistant UTIs otherwise needing IV agent

Question 16

Fosfomycin - mechanism?

Answer 16

Inhibits MurA enzyme
Inhibits bacterial cell wall biogenesis
Bactericidal

Question 17

Moxifloxacin - activity?

Answer 17

Very broad spectrum including:

NORSA
Leprosy
Legionella
TB
Streps
Many gram negatives, anaerobes

Poor pseudomonas, unlike Ciprofloxacin