Basics

Question 1

How do you work out what pathogen it is?

Answer 1

Culture
Gram stains + morphology
Growth requirements
Biochemical reactions + serologic systems

Question 2

how is a gram stain used?

Answer 2

Differentiates bacteria by detecting peptidoglycan in cell wall
If present = positive = violet colour
Negative = red/ pink

Question 3

How do penicillins work?

Answer 3

Has a beta lactam ring that inhibits formation of peptidoglycan cross links in cell wall

Question 4

What bacteria do penicillins work against?

Answer 4

Gram +ve and -ve cocci
Anaerobics
Flucloxacillin = not affected by B lactamase

Question 5

3 generations of cephalosporins

Answer 5

1st = cefradine 
2nd = cefuroxime 
3rd = cefotaxime

Question 6

How do cephalosporins work?

Answer 6

Contain B lactam ring

Question 7

How do carbapenems work + what does it cover?

Answer 7

Contains B lactam ring

Broad spectrum covering positive + negative aerobic + anaerobic

Question 8

How do macrolides work + what are they effective against?

Answer 8

Inhibit protein synthesis
Bacteriostatic
Active against gram +ve + Haemophilus

Question 9

How do glycopeptides work + what are they effective against?

Answer 9

Inhibit peptidoglycan synthesis
Vancomycin = active against gram +ve
Glycopeptides = resistant staph infections + C diff

Question 10

How do aminoglycosides work?

Answer 10

Bacteriacidal - bind to ribosome

Broad spectrum but low against anaerobes, strep + pneumococci

Question 11

How do quinolones work?

Answer 11

Bactericidal - inhibit prokaryotic DNA gyrase (essential for DNA replication + repair)

Question 12

How does metronidazole work?

Answer 12

Inhibitor of obligate anaerobes + protozoa