Antimicrobial resistance

Question 1

Antimicrobial resistance

Answer 1

-serious concern; many deaths a year
-affects everything differently

Question 2

Serious threat examples

Answer 2

-campylobacter
-candida
-extended spectrum beta lactamase producing Enterobacteriaceae

Question 3

ESKAPE organisms

Answer 3

**organisms with emerging resistance

-Enterococcus faecium
-Staphylococcus aureus (pseudintermedius)
-Klebsiella penumoniae
-Acinetobacter baumannii
-Pseudomonas aeruginosa
-Enterobacter spp.

Question 4

Antimicrobial use in Dogs and Cats

Answer 4

beta lactams most commonly prescribed in companion animals
-dogs= amoxicillian clavulanic acid
-dogs= cephalosporin (cefovecin)

Question 5

3rd generation cephalosporin resistance in salmonella

Answer 5

-detected in poultry in Canada
-frequency of resistance increased with poultry drug use. when drug prevention is put in place, saw a decrease in resistance

Question 6

How antibiotics work?

Answer 6

Attack physiological processes or structures
-cell wall
-cell membrane
-nucleic acid synthesis, metabolism, organization
-protein synthesis

Question 7

How bacteria resist?

Answer 7

-decreased permeability
-active efflux
-enzymatic degradation/alteration
-target modification
-alternate pathways
-resistance by absence

Question 9

Determine susceptibility

Answer 9

1. Phenotypic susceptibility tests= categorical or quantitative
2. molecular= look for resistance gene
3. other phenotypic tests= look for gene products
   *used for resistance but not susceptible!

Question 10

What assumptions are used to predict antimicrobial resistance?

Answer 10

-species
-achievable drug concentration in target tissue
-dosing regimen
-target pathogen

Question 11

Resistance types

Answer 11

1. Intrinsic- normal to organisms

2.Acquired- not inherent to organism= decreased susceptibility compared to wild type

Question 12

SPICE organisms

Answer 12

-Serratia
-Providentia
-indole positive proteae
-Citrobacter
-Enterobacter

**produce AmpC beta lactamases so have intrinsic 3rd generation cephalosporin resistance

Question 13

Where does resistance come from?

Answer 13

Natural phenomenon- resistance is often a byproduct of something else
-resistance to every drug that has or will be used already exists
-all drug use results in some sort of selection pressure

Question 14

Where does resistance come from?

Answer 14

1. Mutation
   2.Conjugation
2. Transduction
3. Transformation- picks up DNA from environment and express it themselves

Question 15

Beta-lactams resistance strategies

Answer 15

1.bacteria product altered targets= altered penicillin binding proteins
eg. methicillin, penicillin, intrinsic rod cephalosporins

2. Decreased permeability- shut down porins
   eg. gram negative rods
3. B-lactamases= enzymatic degradation
   eg. bacteria =Means that there is likely something we can try=clavamox!

Question 16

Stewardship

Answer 16

Approaches to sustain clinical efficacy of antimicrobials through responsible use of drugs and minimizing adverse
**context specific and time specific!

Question 17

Drug prescribing decisions

Answer 17

-ID pathogen
-Susceptibility of organism or knowledge of resistance
-animal species
-signalment (eg. male or female dog with UTI)
-site/type if infection
-co-mobilities
-route of administration

Others: cost, client compliance, label indication, withdrawal time

Question 18

Vet specific prescribing decisions

Answer 18

-business factors
-fear factors (licensing loss)
-habitual practice factors (“people get lazy- do what they’ve always done”)
-pharmaceutical factors (influence of pharmaceuticals and marketing)

Question 19

Drugs vs. brands

Answer 19

-recognize impact of marketing= they will discuss tradename, not the drug
-Know active ingredient!
-ensure you critically evaluate information from pharmaceutical companies