Sensi Quiz

Question 1

What organisms should be screened for vanc resistance?

Answer 1

S. aureus and Enterococcus spp

Question 2

Which bug/drug combinations have ECVs for bacteria?

Answer 2

P. acnes and Vanc
Salmonella, Shigella flexneri and sonnei and Azithro
E. coli, K. pneumo, R. orthinolytica, E. cloacae and aerogenes and Colistin
N. gonnorrhoae and Azithro

Question 3

intrinsic Cephalosporin resistance

Answer 3

Enterococcus
Listeria
Bacillus anthracis

Question 4

resistant to ampicillin

Answer 4

HACEK (produce beta-lacatmase, Rx 3rd gen cephalosporin)

Question 5

What isolates of Staph spp are tested for beta-lactamases?

Answer 5

MSSA and MS CoNS

Question 6

intrinsic novobiocin resistance

Answer 6

Staph saprophyticus

Question 7

(generally) sensitive to bactrim

Answer 7

Burkholderia cepacia

Question 8

What specimen source restrictions are there for daptomycin testing?

Answer 8

No respiratory sources

Question 9

Mechanism of action of echinocandins

Answer 9

inhibit 1-3 glucan sythase in glucan sythesis

Question 10

Ampicillin susceptible

Synercid (Quin/Dalf) resistant

Answer 10

E. faecalis

Question 11

Tiers of Beta-lactamases

Answer 11

AmpC (lowest)
ESBL (middle)
Carbapenemases (highest)

Question 12

Orgs we report as ESBLs

Answer 12

Klebsiella pneumoniae
Klebsiella oxytoca
Proteus mirabilis
E. coli

Question 13

resistant to macrolides and clindamycin

Answer 13

Eikenella

Question 14

What drugs should NOT be reported for Salmonella isolates?

Answer 14

1st and 2nd gen cephalosporins and aminoglycosides

Question 15

intrinsic metronidazole resistance

Answer 15

Actinomyces
Proprionibacterium
Lactobacillus

Question 16

What are the CLSI methods to detect carbapenemases and which bugs can they be used on (per CLSI)?

Answer 16

MHT (Enterobacteriaceae)
Carba-NP (Enterobacteriaceae, P. aerug, Acinteo spp)
mCIM (Enterobacteriaceae)
(plus molecular assays for all groups as well)

Question 17

no AST

Answer 17

Legionella

Question 18

Cefoxitin sensitivity screening

Answer 18

Predicts methicillin resistance in Staphylococci

Question 19

Mechanism of action of amphoterecin B

Answer 19

Targets ergosterols and inserts into membrane

Question 20

What methods are used to test for high level aminoglycoside resistance?

Answer 20

Disk diffusion, broth microdilution, and agar dilution

Question 21

intrinsic vancomycin resistance

Answer 21

Pediococcus (PYR-)
Weisella
Erysipelothrix
Enterococcus casseliflavus
Enterococcus gallinarium
Lactobacillus
Leuconostoc (PYR-)

Clostridum innocuum

Question 22

Definition of extended spectrum beta-lactamase (ESBL)

Answer 22

Hydrolyze at least 1 oxy-imino-beta-lactam at a rate of > or = to 10% of that of benzylpenicillin and are inhibited by clavulanic acid

Question 23

What must be added to test fosfomycin AST?

Answer 23

Glucose-6-phosphate, this is added to KB disk, but must be added for MIC method (why agar dilution is only approved method)

Question 24

How ESBLs are detected in the lab

Answer 24

3 doubling dilution shift in MIC w/ clavulanic acid or >= 5mm change in zone diameter for KB testing

Question 25

What is the acceptable "validation" to go to weekly AST QC?

Answer 25

20 or 30 days of consecutive testing of all appropriate QC strains, with no more than 1/20 or 3/30 out of range QCs

Question 26

Which drugs have meningitis and non-meningitis breakpoints for S. penumo?

Answer 26

``` Penicillin amoxicillin Cefepime Cefotaxime Ceftriaxone ```

Question 27

What organisms are tested for high level aminoglycoside resistance?

Answer 27

Enterococcus spp

Question 28

intrinsic bactrim resistance

Answer 28

``` Pseudomonas aeruginosa Strep Groups (BAD) - S.. agalactiae (B) - S. pyogenes (A) - Enterococcus (D) ```

Question 29

Ampicillin resistant | Synercid (Quin/Dalf) susceptible

Answer 29

E. faecium

Question 30

How is beta-lacatmase detection in Staph spp performed

Answer 30

S. aureus and CoNS - cefinase test (red/pink=pos) from zone around cefoxitin disk S. aureus can also do penn KB - sharp edge=pos, fuzzy edge=neg

Question 31

Which bug/drug combination has the SDD category?

Answer 31

Cefepime and Enterobacteriaceae

Question 32

What are appropriate methods to test for methicilin resistance in Staph species?

Answer 32

For S. aureus and S. lugdunensis = Oxacillin MIC or cefoxitin disk/MIC CoNS = Cefoxitin disk or MIC as surrogate for oxacillin S. pseudintermiedius = Oxacillin disk or MIC

Question 33

Which drugs have different breakpoints for S. aureus and CoNS?

Answer 33

Oxacillin (also S. lugdunensis and S. pseudintermedius) | Vancomycin

Question 34

Mechanism of action of azoles

Answer 34

inhibit 14-alpha demethlyase in ergosterol sythesis

Question 35

intrinsic colistin resistance

Answer 35

Burkholderia Serratia Porphyromonas

Question 36

Common orgs with chromosomal AmpC

Answer 36

``` (SPACE!) Serratia Proteus/Pseudomonas* Acinetobacter/Aeromonas Citrobacter* Enterobacter ``` (plus Provdiencia, Hafnia, Morganella...) *not all species have chromosomal AmpC

Question 37

How is a vanc resistance screen done?

Answer 37

On BHI agar with 6ug/ml vanc, resuspension is inoculated directly on to plate and examined for growth of at least 1 colony, if growth, follow with appropriate vanc MIC method

Question 38

Classic test for ESBLs

Answer 38

Double disk synergy test (looks for keyhole structure - where clav. acid inhibits and there is no growth)

Question 39

resistant to all Beta-lactams except imipenem

Answer 39

Campylobacter

Question 40

What agents are tested for high level aminoglycoside resistance?

Answer 40

Genatmysin, Streptomycin

Question 41

sensitive to colistin

Answer 41

Pseudomonas

Question 42

AmpC producers should be reported as "R" to which Abx?

Answer 42

1st and 2nd gen cephalosporins, and the cefamycins

Question 43

What drugs should be reported on Slamonella isolates?

Answer 43

Intestinal - Amp, Fluoroquinolone, Bactrim (SXT) | Extra-intestinal - Above plus third gen cephalosporin

Question 44

What species should be tested for inducible clindamycin resistance?

Answer 44

Staph spp, S. pneumo, and B-heme strep spp that are R to erythro and S or I to clinda