TABLE 1.
Phenotypes and MIC90s determined for the ESBL-producing isolates of K. pneumoniae used in this study
| β-Lactamase genotype | No. of isolates | Cefepime MIC90 (μg/ml) at fixed enmetazobactam concn (μg/ml) of: |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| 0 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | ||
| CTX-M±SHVa | 74 | >32 | >32 | 4 | 1 | 1 | 0.5 | 0.5 | 0.25 |
| CTX-M±SHV+OXA-48b | 10 | >32 | >32 | >32 | >32 | 32 | 16 | 8 | 4 |
| Combined | 84 | >32 | >32 | 32 | 32 | 8 | 2 | 1 | 1 |
a
CTX-M-15 was detected in 65/74 of isolates (87.8%), followed by CTX-M-14 and CTX-M-27 (2 isolates each) and by CTX-M-1, CTX-M-9, CTX-M-22, and CTX-M-55 (1 isolate each). Three isolates harbored an SHV-type ESBL, one together with CTX-M-15 and one together with CTX-M-27.
b
Six isolates coharbored CTX-M-15, 2 isolates coharbored CTX-M-14, and 2 isolates coharbored CTX-M-9 together with an SHV-type ESBL.