Table 1 Breakpoints used to determine resistance and susceptibility to antimicrobial therapy
Antimicrobial Agent | Disk Content | Zone Diameter Breakpoints, nearest whole mm | ||
|---|---|---|---|---|
S | I | R | ||
mezlocillin | 75 μg | ≧ 16 | - | ≦ 15 |
ceftazidime | 30 μg | ≧ 18 | 15-17 | ≦ 14 |
cefoperazone | 75 μg | ≧ 21 | 16-20 | ≦ 15 |
ceftriaxone | 30 μg | ≧ 21 | 14-20 | ≦ 13 |
imipenem | 10 μg | ≧ 16 | 14-15 | ≦ 13 |
aztreonam | 30 μg | ≧ 22 | 16-21 | ≦ 15 |
gentamicin | 10 μg | ≧ 15 | 13-14 | ≦ 12 |
ciprofloxacin | 5 μg | ≧ 21 | 16-20 | ≦ 15 |