ESBL

Question 1

What are ESBLs?

Answer 1

ESBLs are enzymes that mediate resistance to:
- Extended-spectrum 3rd gen Cephalosporins
- Monobactams

However they do NOT affect:
- Carbapenems (Imipenem)
- Cephamycins

Question 2

Where are ESBLs located?

Answer 2

ESBLs are located on plasmids that are transmitted from strain to strain.

Question 3

What are beta-lactamase inhibitors?

Answer 3

Beta- lactamase inhibitors like Clavulanic acid inhibit the ESBL producing strains

Question 4

What are the resistant genes associated with ESBL?

Answer 4

• TEM
• SHV
• CTX-M
• OXA —> hydrolyzes oxacillin and other anti-staph penicillins
• AMP-C

Question 5

What are the differences between ESBL and AMP-C?

Answer 5

ESBL
 Spectrum “extended” from
parent enzyme
 Inhibited by clavulanate
 Can hydrolyze cefepime at
high inoculum
 Carbapenem susceptible

ampC
 Spectrum not “extended,”
although may be basal or
hyperproducing level
 Not inhibited by clav
 Hydrolyzes cefepime poorly
 Carbapenem susceptible

Question 6

What are the tests used for the detection of ESBLs?

Answer 6

Combination test
Double disk test
E test

Question 7

What is CRE?

Answer 7

CRE, which stands for carbapenem- resistant Enterobacteriaceae, are
strains of bacteria that are resistant to carbapenem, a class of antibiotic used to treat severe infections, as well as most other antibiotics commonly used today. In some cases, CRE are resistant to all available antibiotics

Question 8

What are the resistance genes associated with CRE?

Answer 8

KPC : Klebsiella pneumonia carbapanemese
MBL : Metallo-beta lactamase
OXA carbapanemase

Question 9

What are some characteristics of CRE?

Answer 9

Resistant to ALL penicillin, cephalosporin and carbapenem
 Resistant to other antibiotic may occur (Fluoroquinolones, and aminoglycosides
 Spread rapidly from person to person