Table 3 Antimicrobials used, their symbols, and corresponding zones of inhibition for gram-negative enteric bacteria
Antimicrobial used | Symbol | Diameter of zone of inhibition (mm) | ||
|---|---|---|---|---|
Resistant | Intermediate | Susceptible | ||
Amoxicillin (25 μg) | AML | ≤13 | 14–16 | ≥17 |
Ampicillin (10 μg) | AMP | ≤13 | 14–17 | ≥18 |
Bacitracin (10 μg) | B | ≤14 | 15–16 | ≥17 |
Cefotaxime (30 μg) | CTX | ≤14 | 15–22 | ≥23 |
Cefoxitin (30 μg) | FOX | ≤14 | 15–17 | ≥18 |
Ceftazidime (10 μg) | CAZ | ≤12 | 13–17 | ≥18 |
Cefuroxime sodium (5 μg) | CXM | ≤14 | 15–22 | ≥23 |
Chloramphenicol (30 μg) | CHL | ≤14 | 15–20 | ≥21 |
Ciprofloxacin (30 μg) | CIP | ≤15 | 16–20 | ≥21 |
Cloxacillin (5 μg) | CLOXA | ≤13 | 14–16 | ≥17 |
Doxycycline (30 μg) | DO | ≤13 | 14–16 | ≥17 |
Gentamycin (10 μg) | GEN | ≤12 | 13–15 | ≥16 |
Kanamycin (30 μg) | K | ≤13 | 14–17 | ≥18 |
Nalidixic acid (30 μg) | NAL | ≤13 | 14–18 | ≥19 |
Nitrofurantoin (300 μg) | F | ≤13 | 14–17 | ≥18 |
Norfloxacin (10 μg) | NOR | ≤12 | 13–16 | ≥17 |
Polymyxin B (300 units) | PMB | ≤8 | 9–11 | ≥12 |
Streptomycin (10 μg) | STR | ≤11 | 12–14 | ≥15 |
Tetracycline (30 μg) | TET | ≤12 | 15–18 | ≥19 |
Vancomycin (30 μg) | VAN | ≤14 | 15–16 | ≥17 |