Table 3.
Distribution of MICs of different antibiotics against CoNS isolates (55 isolates)
| Antibiotic | Break Point* µg/ml | MIC in Mg/ml | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| <0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | 32 | 64 | 128 | 256 | 512 | ||
| β-lactams: | |||||||||||||
| a. Penicillins: | |||||||||||||
| Ampicillin | 0.25 | 6 | 5 | 4 | 3 | 6 | 5 | 8 | 6 | 3 | 5 | 1 | 2 |
| Amoxycillin | 0.25 | 11 | 11 | 5 | 4 | 2 | 6 | 4 | 4 | 2 | 3 | 1 | 1 |
| Oxacillin | 2 | 10 | 15 | 12 | 5 | 2 | 3 | 2 | 2 | 1 | 1 | 2 | 0 |
| b. Cephalosporins: | |||||||||||||
| Cephalexin | 16 | 0 | 0 | 2 | 3 | 2 | 4 | 6 | 10 | 12 | 8 | 5 | 3 |
| Cefuroxime | 8 | 0 | 0 | 3 | 4 | 1 | 8 | 9 | 14 | 9 | 5 | 1 | 1 |
| Cefoperazone | 16 | 0 | 0 | 5 | 7 | 2 | 8 | 5 | 6 | 11 | 9 | 2 | 0 |
| Cefotaxime | 8 | 0 | 0 | 2 | 2 | 3 | 5 | 7 | 8 | 13 | 9 | 3 | 3 |
| Cefepime | 8 | 6 | 7 | 5 | 3 | 4 | 7 | 5 | 8 | 6 | 4 | 0 | 0 |
| β-lactam β-lactamase | |||||||||||||
| inhibitor combinations: | |||||||||||||
| Amp/Sul** | 8 | 2 | 3 | 8 | 9 | 5 | 8 | 4 | 7 | 7 | 2 | 0 | 0 |
| Amox/Clav** | 4 | 7 | 6 | 5 | 3 | 7 | 9 | 7 | 3 | 4 | 3 | 1 | 0 |
| Aminoglycosides: | |||||||||||||
| Gentamicin | 4 | 9 | 12 | 10 | 9 | 7 | 2 | 3 | 2 | 1 | 0 | 0 | 0 |
| Amikacin | 16 | 16 | 13 | 6 | 11 | 5 | 2 | 2 | 0 | 0 | 0 | 0 | 0 |
| Fluoroquinolones: | |||||||||||||
| Ciprofloxacin | 1 | 0 | 8 | 12 | 13 | 9 | 7 | 3 | 1 | 2 | 0 | 0 | 0 |
| Norfloxacin | 4 | 0 | 4 | 3 | 7 | 3 | 9 | 12 | 8 | 5 | 4 | 0 | 0 |
| Ofloxacin | 1 | 3 | 12 | 10 | 8 | 11 | 6 | 3 | 1 | 1 | 0 | 0 | 0 |
| Levofloxacin | 1 | 13 | 21 | 10 | 8 | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Gatifloxacin | 0.5 | 25 | 20 | 8 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Macrolides: Erythromycin | 0.5 | 5 | 6 | 8 | 9 | 6 | 7 | 2 | 3 | 3 | 4 | 1 | 1 |
| Lincosamides: Clindamycin | 0.5 | 10 | 12 | 11 | 8 | 5 | 2 | 3 | 2 | 1 | 1 | 0 | 0 |
| Tetracyclines: Tetracycline | 4 | 0 | 6 | 8 | 4 | 5 | 7 | 9 | 6 | 5 | 2 | 2 | 1 |
| Glycopeptides: Vancomycin | 4 | 12 | 6 | 9 | 11 | 5 | 7 | 4 | 4 | 1 | 0 | 0 | 0 |
| Phenicols: Chloramphenicol | 8 | 0 | 5 | 2 | 8 | 6 | 7 | 3 | 9 | 6 | 2 | 5 | 2 |
| Ansamycins: Rifampicin | 1 | 6 | 8 | 11 | 14 | 10 | 4 | 2 | 0 | 0 | 0 | 0 | 0 |
a
Break points of different antibiotics according to CLSI (2005).