Minimum Inhibitory
Concentrations
(mcg/mL)

Disk Diffusion
(zone diameter in mm)

Pathogen

S

I

R

S

I

R

Enterobacterales

M100 standard is recognized

Acinetobacter spp.

≤1

2

≥4

-

-

-

Other non-Enterobacterales

≤1

2

≥4

-

-

-

Haemophilus influenzae and parainfluenzae

≤1

-

-

-

-

-

Neisseria gonorrhoeae

M100 standard is recognized

Streptococcus pneumoniae
(meningitis)

M100 standard is recognized

-

-

-

Streptococcus pneumoniae
(non-meningitis)

M100 standard is recognized

-

-

-

Streptococcus spp β- Hemolytic Group

M100 standard is recognized

Streptococcus spp Viridans Group

M100 standard is recognized

Neisseria meningitidis

M100 standard is recognized

Anaerobes

≤1

2

≥4

-

-

-

S = Susceptible; I = Intermediate; R = Resistant