Principles of Anti-Infective Therapy

Question 1

Gram Positive (PPP shortcut)

Answer 1

gram Positive
stains Purple
Peptidoglycan layer
Penicillin works well on these
eXotoxins is what they create (X is a + on its side)

Question 2

Gram Negative (NNN shortcut)

Answer 2

gram Negative
Not purple
Not Nice lipopolysaccharide lyaer
eNdotoxins are what they make

Question 3

What resource trumps Sanford Guide?

Answer 3

Regional beta! Every region and community can have it’s own treatment regimen based on bugs.

Question 4

What are the 3 types of antibiotic trx options?

Answer 4

Prophylactically = trx before based one exposure
Empirically = trx based on best guess of what bug is
Definitively = trx based on lab/culture results

Question 5

Cell wall synthesis inhibitors

Answer 5

Disrupts Gram (+) cell wall
Bacteriacidal
Beta-lactams
i.e. Penicillin, Vancomyacin, Amoxicillin, Cephalexin

Question 6

Protein synthesis inhibitors

Answer 6

Prevents bacterial proteins from being formed
Bacteriastatic (except when it binds irreversibly)
Good for Facultative Intracellular Organisms
i.e. Gentomycin

Question 7

Nucleic Acid Synthesis Inhibitors

Answer 7

Interferes with DNA replication
Gram (-)
i.e. Quinolones, Rifampin

Question 8

Cytoplasmic membrane inhibition

Answer 8

Punches holes into plasma membrane
Not great for us b/c it effects our cells too
i.e. Polymyxin B

Question 9

Antifungals

Answer 9

Impacts active transport/production of Ergosterol
Ergosterol = fungal cell wall building block
Weakens cell wall of fungus

Question 10

Hypersensitivity

Answer 10

Type I, II, III, IV

ALWAYS document a pt’s rxn to antibiotic

Question 11

Secondary Infection

Answer 11

Get rid of 1 bug and another one pops up.

i.e. C. Diff, Yeast infections

Question 12

2 levels of antibiotic resistance

Answer 12

1. Pt level: resistance within pt (recurrent UTI)

2. Societal level: more ppl on drug, the more bacteria build up resistance

Question 13

Mechanism of Resistance

Answer 13

DISABLE = inactivation of the antibiotic (beta-lactamase)
DISGUISE = modify the target proteins (MRSA)
DETER = impair entry of antibiotic into bacteria
DISCHARGE = ejection of antibiotic by EFFLUX pumps

Question 14

Treatment Guidelines

Answer 14

1. Don’t use abx to treat colonization (virus vs bacteria)
2. Target the bug as much as possible; aim for Narrow Spectrum drug
3. Proper Dose
4. Use shortest effective duration (not studied well)