Bugs and MOR

Question 1

MSSA

Answer 1

-NSBLs

Question 2

MRSA

Answer 2

• NSBLs
• modified PBPs
• only requires single point mutation and high mutation rate to FQs

Question 3

MSSE

Answer 3

• 90% make NSBLs

- empirically assume it’s MRSE

Question 4

MRSE

Answer 4

• NSBLs

- modified PBPs

Question 5

PSSP

Answer 5

-don’t make beta-lactamases

Question 6

PRSP

Answer 6

-don’t make beta-lactamases
-modified PBPs
functionally resistant
*very slow mutation rate to develop FQ resistance…not a lot of gyrase resistance. Main target is PAR for FQ…main resistance is efflux pumps!

Question 7

Any other streptococci

Answer 7

• no beta-lactamases

- strep. viridans most resistant of these

Question 8

Enterococcus faecalis

Answer 8

• no beta-lactamases
• modified PBPs
• VRE=modified PTG to become vancomycin resistant

Question 9

Enterococcus faecium

Answer 9

• no beta-lactamases
• modified PBPs
• VRE=modified PTG to become vancomycin resistant

Question 10

Listeria monoctyogenes

Answer 10

• no beta-lactamases
• modified PBPs
• PBPs are similar to enterococci but their ribosome is more similarto traditional G+ bugs (so macrolides work)

Question 11

Corynebacterium

Answer 11

-modified PBPs (similar to enterococci)

Question 12

Bacillus

Answer 12

-no beta-lactamases

Question 13

Acinetobacter

Answer 13

-modified PBPs
-modified pores
-70-90% make BSBL
-some can make carbapenamases
only requires single point mutation and high mutation rate to FQs

Question 14

Moraxella catarrhalis

Answer 14

• “simple G-“

- 20-50% make BSBL (up to 75%)

Question 15

Neisseria gonorrhea

Answer 15

• 20-50% make BSBL

- some have modified PBP–>if it does, NO penicillin will work

Question 16

Neisseria meningitidis

Answer 16

• “simple G-“
• no beta-lactamases
• some have modified PBPs (PRNM)
• vaccine available!

Question 17

Haemophilus influenza

Answer 17

• “simple G-“
• 20-50% make BSBL
• vaccine available!
• many strains (<50% but still significant) have become resistant to marcolides via mef genes

Question 18

Pasturella/Eikenella

Answer 18

• “simple G-“

- no beta-lactamases

Question 19

Escherichia coli

Answer 19

• 20-50% make BSBL
• possible to make IRBSBL which chops up ALL penicillins
• 20% make ESBL (more likely to see in hospital infections)
• requires multiple mutations and relatively slow rate of mutation for FQ resistance

Question 20

Salmonella

Answer 20

-20% make BSBLs

Question 21

Shigella

Answer 21

-20% make BSBLs

Question 22

Proteus mirabilis

Answer 22

• least likely to make beta-lactamases

- -if it does make one, it’s BSBL

Question 23

Proteus vulgaris

Answer 23

• most make BSBL

- modified PBPs

Question 24

Klebsiella

Answer 24

• 70-90% make BSBL
• 20% make ESBL
• some make carbapenamases

Question 25

Citrobacter (Morganella, Providencia)

Answer 25

- 70-90% make BSBL | - 20% make AmpC but this gene is usually repressed

Question 26

Enterobacter

Answer 26

- 70-90% make BSBL - 20% make AmpC but gene usually repressed - some make carbapenamases

Question 27

Serratia

Answer 27

- 70-90% make BSBL - 20% make AmpC but gene usually repressed - some make carbapenamases

Question 28

Pseudomonas aeruginosa

Answer 28

-restrictive outer membrane -70-90% make BSBLs -20% make AmpC -some make carbapenamases -unique PBPs some resistance by modified porins to Aztreonam *only requires single point mutation and high mutation rate to FQs…get end treatment resistance!!

Question 29

Stenotrophomonas maltophilia

Answer 29

-make carbapenamases

Question 30

Burkholderia cepacia

Answer 30

-multiple MOR

Question 31

Legionella pneumophilia

Answer 31

- "simple G-" | - low affinity PBPs

Question 32

Bacteroides fragilis

Answer 32

-70-90% make BSBL

Question 33

Clostridium

Answer 33

-no beta-lactamases

Question 34

Clostridium difficile

Answer 34

- does make beta-lactamases | - has spores

Question 35

Peptostreptococcus, Propionibacterium

Answer 35

-no beta-lactamases

Question 36

Mycoplasma

Answer 36

-no cell wall

Question 37

Mycobacteria

Answer 37

-acid fast

Question 38

Campylobacter jejuni

Answer 38

*requires multiple mutations and relatively slow rate of mutation for FQ resistance