27. Resistant Bacteria

Question 1

What is the method of resistance of penicillin resistant pneumococci?

Answer 1

Modified PBP structure

Question 2

What infections are associated with penicillin resistant pneumococci?

Answer 2

Community acquired pneumonia
BSI
Meningits

Question 3

What are the lab results for penicillin resistant pneumococci?

Answer 3

Catalase negative
Oxidase negative
Gram + diplococcus
alpha haemolytic
optochin susceptible

Question 4

What antibiotics might penicillin resistant pneumococci have cross resistance to?

Answer 4

Cephalosporins
Clarithromycin
Tetracyclines
Co-trimoxazole

Question 5

What should penicillin resistant pneumococci be treated with?

Answer 5

Vancomycin and cephalosporins

Question 6

How does resistance arise in penicillin resistant pneumococci?

Answer 6

Acquisition of genes/transposons

Question 7

How can penicillin resistant pneumococci infections be prevented?

Answer 7

23-valent pneumococcal polysaccharide vaccine

Question 8

What infections are caused by MRSA?

Answer 8

SSI
Device related
BSI
Cellulitis

Question 9

What are the lab results of MRSA?

Answer 9

Gram + cocci in clusters
Coagulase and catalase +
Ferments manitol

Question 10

What is the resistance mechanism of MRSA?

Answer 10

Target site modification of PBP

Associated with mecA gene on chromosome

Question 11

What other antibiotics might MRSA be resistant to?

Answer 11

Erythromycin (macrolide)
Gentamicin (aminoglycoside)
Ciproflaxin (quinolone)

Question 12

What agents can MRSA be treated with?

Answer 12

Glycopeptides
Linezolid
Daptomycin
Tigecycline

Question 13

How is MRSA infection prevented?

Answer 13

By standard precautions and decolonisation

Question 14

What does VRE stand for?

Answer 14

Vancomycin Resistant Enterococci

Question 15

Where are VREs found?

Answer 15

Enteric tract

Vagina

Question 16

What infections can be caused by VRE?

Answer 16

UTIs
BSIs
Central line infections
Peritonitis
SSIs

Question 17

What are the lab results for VRE?

Answer 17

Gram + cocci in short chains
Oxidase positive
Catalase negative
Haemolytic growth patterns
Magenta on McConkey agar

Question 18

What resistance is given by the vanA gene?

Answer 18

Resistance to vancomycin and teicoplanin

Question 19

What resistance is given by the vanB gene?

Answer 19

Vancomycin

Question 20

What is the mechanism of resistance in VREs?

Answer 20

Alteration of AA side chains in peptidoglycan cell wall

Question 21

What factor can predispose to a VRE infection?

Answer 21

Prior administration of cephalosporins, macrolides, fluoroquinones

Question 22

How is VRE treated?

Answer 22

Linezolid

Question 23

What is ESBL?

Answer 23

Extended spectrum Beta Lactamase

Question 24

Name 3 bacteria that produce EBSL

Answer 24

E.coli
Klebsiella
Proteus

Question 25

What agar are EBSL producers cultured on?

Answer 25

MacConkey

Question 26

What infections are caused by EBSL producers?

Answer 26

UTI Intra-abdominal SSI

Question 27

How is EBSL acquired?

Answer 27

Plasmids

Question 28

What antibiotic should be prescribed for severe ESBL producer infections?

Answer 28

Meropenem (carbapenem)

Question 29

What antibiotic can be given for uncomplicated ESBL cystitis?

Answer 29

Nitrofuratoin

Question 30

What antibiotics can be used to treat ESBL producers, depending on the MIC?

Answer 30

Gentamicin Amikacin Ciproflaxin

Question 31

What is the mechanism of action of colistin?

Answer 31

Binds to LPS and phospholids on the outer membrane of gram -

Question 32

What infections is colistin used in?

Answer 32

HCAIs | CF lung infections

Question 33

What treatment can be used for carbapenemase-producing enterbacteriacae?

Answer 33

Tigecycline Colistin Fosfomycin

Question 34

How was glycopeptide resistant staph aureus created?

Answer 34

Transfer of van genes from VRE to MRSA

Question 35

What infections are caused by GRSA

Answer 35

Central line BSI Ventilator associated pneumonia SSI

Question 36

how is GRSA treated?

Answer 36

Linezolid