TABLE 3.
Distribution of BMD results for the ATM–CZA combination for the 61 study isolates that tested non-susceptible to both ATM and CZA individually, as categorized by their β-lactamase genotype
| Organisms | β-Lactamasea | Totalb | ATM–CZA susceptibility by BMD | |
|---|---|---|---|---|
| S (%) | R (%) | |||
| Enterobacterales | MBL | 28 | 26 (92.9) | 2 (7.1) |
| Non-MBL | 7 | 4 (57.1) | 3 (42.9) | |
| Total | 35 | 30 (85.7) | 5 (14.3) | |
| P. aeruginosa | MBL | 5 | 0 | 5 (100) |
| GES | 8 | 3 (37.5) | 5 (62.5) | |
| Non-MBL, non-GES | 6 | 0 | 6 (100) | |
| Total | 19 | 3 (15.8) | 16 (84.2) | |
| S. maltophilia | L1 | 7 | 6 (85.7) | 1 (14.3) |
| All organisms | 61 | 39 (64) | 22 (36) | |
a
MBL, metallo-beta-lactamase; GES, Guiana extended-spectrum beta-lactamase.
b
Non-susceptible to ATM alone and CZA alone.