TABLE 4.
Scattergrams of ceftolozane-tazobactam comparing susceptibilities of 245 CTX-M-producing E. coli strains across testing methods
| Ceftolozane-tazobactam MIC (μg/ml) by BMD/Etest | Ceftolozane-tazobactam zone diam (mm) |
||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
| BMDa | |||||||||||||||
| 2 | 1 | 1 | 1 | 2 | 4 | 4 | 1 | 1 | |||||||
| 1 | 1 | 1 | 4 | 11 | 11 | 7 | 5 | 4 | 3 | 1 | |||||
| 0.5 | 1 | 3 | 3 | 4 | 15 | 28 | 45 | 45 | 21 | 10 | 6 | 1 | |||
| ≤0.25 | |||||||||||||||
| Etestb | |||||||||||||||
| 2 | 1 | ||||||||||||||
| 1 | 1 | 4 | 1 | 3 | 2 | 1 | |||||||||
| 0.5 | 1 | 1 | 1 | 4 | 5 | 10 | 9 | 6 | 1 | 2 | |||||
| ≤0.25 | 3 | 4 | 19 | 31 | 46 | 45 | 25 | 11 | 7 | 1 | |||||
a
Ceftolozane MICs in µg/ml as determined by broth microdilution in the presence of 4 µg/ml tazobactam, compared with zone diameters in mm.
b
Ceftolozane-tazobactam MICs in µg/ml as determined by Etest, compared with zone diameters in mm.