Exam 1: MDROs (OBrien)

Question 1

gram POS MDRO (2)

Answer 1

• staph

- enterococcus

Question 2

gram NEG MDRO (3)

Answer 2

• Enterobacteriaceae
• Actinetobacter
• pseudomonas

Question 3

NO ESCAPE (6)

pathogens that escape the activity of common used antibx

Answer 3

Enterococcus faecium
Staphylococcus aureus 
Clostridium difficile
Acinetobacter baumannii
Pseudomonas aeruginosa
Enterobacteriaceae

Question 4

Infections of MDROs are associated with (3)

Answer 4

• higher rates of hospitalization
• greater length of hospital satay
• higher rates of illness

Question 5

MRSA

Methicillin resistance is conferred by the ______

Answer 5

mecA gene (encodes a PBP w/ decreased affinity for beta-lactam antibx

Question 6

Overall difference between HA-MRSA and CA-MRSA

Answer 6

HA-MRSA is resistant not only to methicillin, BUT also other drug classes, while CA-MRSa is still susceptible to some other drug classes

Question 7

_______is typically associated with skin and soft tissue infections

Answer 7

CA-MRSA

Question 8

VRE

Answer 8

resistance to Vanco identified among enterococci due to VanA and VanB genes

Question 9

hVISA

Answer 9

vancomycin heteroresistance

(still in susceptible range for MIC, but there are sub populations that are resistant–> The closer the MIC gets to break point–> you are at greater risk of sub populations occurring)

Question 10

VISA

Answer 10

vanco intermediate resistance

Question 11

VRSA

Answer 11

vanco resistant

Question 12

Vanco breakpoint for susceptible

Answer 12

2

Question 13

Vanco breakpoint for intermediate

Answer 13

4-8

Question 14

Vanco breakpoint for resistant

Answer 14

greater than 16

Question 15

_____ serves as the precursor for VISA

Answer 15

hVISA (especially if vanco is underdosed)

Question 16

_____ and ___ DO NOT possess vancomycin resistant genes

Answer 16

hVISA and VISA

they just bind additional sites throughout the cell wall

Question 17

strain acquired the vancomycin resistance gene cluster vanA from VRE

Answer 17

VRSA

Question 18

Enterococcus faecalis OR faecium

Which is associated with the most MDR?

Answer 18

enterococcus faecium

i.e VRE

Question 19

Hydrolyze early PENs

Answer 19

penicillinases

Question 20

Hydrolyze penicillins and 1st generation cephalosporins

Answer 20

broad spectrum beta-lactamases

Question 21

Hydrolyze most beta lactams except CEFEPIME and CARBAPENEMS

Answer 21

ampC type cephalosporinases

Question 22

Hydrolyze most beta lactams except carbapenems

Answer 22

ESBL

Question 23

Hydrolyze most beta lactams including carbapenems

Answer 23

Carbapenemases

Question 24

TX for CRE

Answer 24

Combo therapy

Question 25

TX for ESBL

Answer 25

carbapenems

Question 26

Although CRE is resistant to carbapenems we can still use…

Answer 26

carbapenems JUST at high dose expended infusion

Question 27

What is unique about sulbactam?

Answer 27

beta-lactamase inhibitor (protects the beta-lactam from being hydrolyzed by beta-lactamase)

intrinsic activity against acinetobacter