A SMALL INTRODUCTION INTO ANTIBIOTIC SUSCEPTIBILITY TESTING

Susceptibility of Escherichia coli to seven basic antibiotics

Disk diffusion test (method)
Kirby-Bauer test

E.coli

Escherichia coli

Urinary Tract Infections

UTI's

E.coli

E.coli

Resistance patterns

Overview

E.coli

E.coli

Treatment options

paper antibiotic disks

Antibiotic disks

Generic names vs.
Brand names

disk diffusion test

Disk diffusion test

Inoculum preparation

disk diffusion method

Disk diffusion test

Inoculation onto agar plate

Kirby-Bauer test

Disk diffusion test
Kirby-Bauer test

Interpretation

reading zones

Reading of zones

E.coli susceptible strain

E.coli

Disk diffusion test

No: ESCO_1

E.coli susceptible strain

E.coli

Disk diffusion test

No: ESCO_2

E.coli resistant to ampicillin

E.coli

Disk diffusion test

No: ESCO_3

E.coli resistant to co-trimoxazole

E.coli

Disk diffusion test

No: ESCO_4

E.coli susceptible strain

E.coli

Susceptible strain

No: ESCO_1

E.coli susceptible strain

E.coli

Susceptible strain

No: ESCO_2

E.coli resistant to ampicillin

E.coli

Resistant to ampicillin

No: ESCO_3

E.coli resistant to co-trimoxazole

E.coli

Resistant to trimethoprim/sulfamethoxazole
(Co-trimoxazole)

No: ESCO_4

E.coli resistant to nitrofurantoin

E.coli

Disk diffusion test

No: ESCO_5

E.coli resistant to fluorochinolones

E.coli

Disk diffusion test

No: ESCO_6

E.coli resistant to ampicillin and co-trimoxazole

E.coli

Disk diffusion test

No: ESCO_7

E.coli resistant to ampicillin and ciprofloxacin

E.coli

Disk diffusion test

No: ESCO_8

E.coli resistant to nitrofurantoin

E.coli

Resistant to nitrofurantoin

No: ESCO_5

E.coli resistant to fluorochinolones

E.coli

Resistant to ciprofloxacin

No: ESCO_6

E.coli resistant to ampicillin and co-trimoxazole

E.coli

Resistant to
ampicillin
co-trimoxazole

No: ESCO_7

E.coli resistant to ampicillin and ciprofloxacin

E.coli

Resistant to
ampicillin
ciprofloxacin

No: ESCO_8

E.coli resistant to ampicillin and amoxicillin/clavulanate

E.coli

Disk diffusion test

No: ESCO_9

E.coli resistant to Trimethoprim-Sulfamethoxazole (Co-trimoxazole), TMP-SMX

E.coli

Disk diffusion test

No: ESCO_10

E.coli ESBL positive

E.coli

Disk diffusion test

No: ESCO_11

E.coli ESBL+

E.coli

Disk diffusion test

No: ESCO_12

E.coli resistant to ampicillin and amoxicillin/clavulanate

E.coli

Resistant to
ampicillin
amoxicillin/clavulanate

No: ESCO_9

E.coli resistant to Trimethoprim-Sulfamethoxazole (Co-trimoxazole), TMP-SMX

E.coli

Resistant to
trimethoprim/sulfamethoxazole
ciprofloxacin

No: ESCO_10

E.coli ESBL positive

ESBL-producing E.coli

Resistant to
ampicillin
cefuroxime
trimethoprim/sulfamethoxazole
ciprofloxacin

No: ESCO_11

E.coli ESBL+

ESBL-producing E.coli

Resistant to
ampicillin
amoxicillin/clavulanate
cefuroxime

No: ESCO_12

How to test antibiotics?
Four short EUCAST videos on YouTube:

eucast link 1

Preparation of inoculum

eucast link 2

Inoculation

eucast link 3

Application of disks

eucast link 4

Reading of zones

E.coli ESBL positive, Augmentin susceptible

E.coli

Disk diffusion test

No: ESCO_13

AmpC positive

E.coli

Disk diffusion test

No: ESCO_14

AmpC positive

E.coli

Disk diffusion test

No: ESCO_15

AmpC positive

E.coli

Disk diffusion test

No: ESCO_16

E.coli ESBL+, augmentin susceptible

ESBL-producing E.coli

Resistant to
ampicillin
cefuroxime
ciprofloxacin

No: ESCO_13

E.coli AmpC positive

AmpC-beta-lactamase-producing E.coli

Resistant to
ampicillin
amoxicillin/clavulanate
cefuroxime

No: ESCO_14

E.coli

E.coli

Resistant to
ampicillin
trimethoprim/sulfamethoxazole
ciprofloxacin

No: ESCO_15

E.coli

E.coli

Resistant to
ampicillin
trimethoprim/sulfamethoxazole
ciprofloxacin
nitrofurantoin

No: ESCO_16

ESBL positive

E.coli

Disk diffusion test

No: ESCO_17

ESBL positive

E.coli

Disk diffusion test
No: ESCO_18

ESBL positive

E.coli

Disk diffusion test
No: ESCO_19

ESBL positive

E.coli

Disk diffusion test
No: ESCO_20

E.coli

ESBL-producing E.coli

Susceptible to
trimethoprim/sulfamethoxazole
ciprofloxacin

No: ESCO_17

E.coli ESBL

ESBL-producing E.coli

Susceptible to

fosfomycin
nitrofurantoin

No: ESCO_18

E.coli ESBL

E.coli

Resistant to

fosfomycin
nitrofurantoin

No: ESCO_19

E.coli ESBL

ESBL-producing E.coli

No: ESCO_20

inoculated Petri dish with antibiotic disks

Inoculated plate

ESBL E.coli

ESBL

E.coli

interpretation

Interpretation

antibiotic structure

Per os (p.o.)
antibiotics

For
Enterobacterales

inoculated Petri dish with antibiotic disks overnight cultivation

Overnight cultivation

E.coli ESBL

ESBL

E.coli

E.coli vs. P.aeruginosa susceptibility comparison

E.coli

E.coli vs. P.aeruginosa

antibiotic structure2

Intravenous (i.v.)
antibiotics

For
Enterobacterales

non-AmpC/ESBL-producing Escherichia coli

non-ESBL E.coli

E.coli

Antibiotic set 1

No.: ESCO_7

non-ESBL E.coli

E.coli

Antibiotic set 2

No.: ESCO_7

non-ESBL E.coli

E.coli

AmpC, ESBL,
carbapenemase detection

No.: ESCO_7

non-ESBL E.coli

E.coli

Summary

No.: ESCO_7

non-ESBL E.coli

E.coli

Antibiotic set 1

No.: ESCO_15

non-ESBL E.coli

E.coli

Antibiotic set 2

No.: ESCO_15

non-ESBL E.coli

E.coli

AmpC, ESBL,
carbapenemase detection

No.: ESCO_15

non-ESBL E.coli

E.coli

Summary

No.: ESCO_15

AmpC-beta-lactamase-producing Escherichia coli

AmpC positive E.coli

E.coli

Antibiotic set 1

No.: ESCO_33

E.coli

Antibiotic set 2

No.: ESCO_33

AmpC producing E.coli

E.coli

AmpC, ESBL,
carbapenemase detection

No.: ESCO_33

E.coli AmpC antibiogram

E.coli

Summary

No.: ESCO_33

ESBL-producing Escherichia coli

E.coli ESBL

E.coli

Antibiotic set 1

No.: ESCO_34

ESBL positive E.coli

E.coli

Antibiotic set 2

No.: ESCO_34

ESBL positive

E.coli

AmpC, ESBL,
carbapenemase detection

No.: ESCO_34

ESBL producing E.coli

E.coli

Summary

No.: ESCO_34

Susceptibility of Pseudomonas aeruginosa

Disk diffusion test

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_1A

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_1B

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_1C

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_1D

p.aeruginosa antibiotic testing

P.aeruginosa

Susceptible strain

No: PSAE_1A

p.aeruginosa antibiotic testing

P.aeruginosa

Susceptible strain

No: PSAE_1B

p.aeruginosa antibiotic testing

P.aeruginosa

Susceptible strain

No: PSAE_1C

p.aeruginosa antibiotic testing

P.aeruginosa

Susceptible strain

No: PSAE_1D

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_2

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_3

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_4

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_5

p.aeruginosa antibiotic testing

P.aeruginosa

Susceptible strain

No: PSAE_2

p.aeruginosa antibiotic testing

P.aeruginosa

Susceptible strain

No: PSAE_3

p.aeruginosa antibiotic testing

P.aeruginosa

No: PSAE_4

p.aeruginosa antibiotic testing

P.aeruginosa

No: PSAE_5

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_6

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_7

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_8

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_9

p.aeruginosa antibiotic testing

P.aeruginosa

No: PSAE_6

p.aeruginosa antibiotic testing

P.aeruginosa

No: PSAE_7

p.aeruginosa antibiotic testing

P.aeruginosa

No: PSAE_8

p.aeruginosa antibiotic testing

P.aeruginosa

No: PSAE_9

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_10A

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_10B

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_10C

p.aeruginosa antibiotic testing

P.aeruginosa

Disk diffusion test

No.: PSAE_10D

Susceptibility of Staphylococcus aureus

Disk diffusion method/test

s.aureus antibiogram 1

S.aureus

Disk diffusion test

No.: STAU_1

s.aureus antibiogram 2

S.aureus

Disk diffusion test

No.: STAU_2

s.aureus antibiogram 3

S.aureus

Disk diffusion test

No.: STAU_3

s.aureus antibiogram 4

S.aureus

Disk diffusion test

No.: STAU_4

s.aureus antibiogram 1 breakpoints

S.aureus

Disk diffusion test

No.: STAU_1

s.aureus antibiogram 2 breakpoints

S.aureus

Disk diffusion test

No.: STAU_2

s.aureus antibiogram 3 breakpoints

S.aureus

Disk diffusion test

No.: STAU_3

s.aureus antibiogram 4 breakpoints

S.aureus
MRSA

Inducible clindamycin resistance

No.: STAU_4