Table 4.
Prevalences of ampC, mexB, and mexY overexpression among isolates showing particular resistance phenotypes
| No. (%) of isolates | Resistance phenotypea |
No. (%) of isolates showing overexpression of: |
|||||
|---|---|---|---|---|---|---|---|
| IMP | MER | CAZ | FEP | ampC | mexB | mexY | |
| 190 (100) | All | All | All | All | 46 (24.2) | 24 (12.6) | 25 (13.2) |
| 95 (50) | S | S | S | S | 4 (4.2) | 5 (5.3) | 2 (2.1) |
| 21 (11.1) | R | S | All | All | 4 (19.0) | 1 (4.8) | 4 (19.0) |
| 40 (21.1) | R | R | All | All | 25 (62.5) | 12 (30.0) | 13 (32.5) |
| 30 (15.8) | All | All | S | R | 1 (3.3) | 8 (26.7) | 13 (43.3) |
| 43 (22.6) | All | All | R | R | 37 (86.0) | 10 (23.3) | 8 (18.6) |
| 27 (14.2) | R | R | R | R | 24 (88.9) | 8 (29.6) | 8 (29.6) |
a
IMP, imipenem; MER, meropenem; CAZ, ceftazidime; FEP, cefepime. “R” phenotypes include CLSI intermediate and resistant categories. Imipenem-sensitive–meropenem-resistant (n = 3) and ceftazidime-susceptible–cefepime-resistant (n = 2) phenotypes were not included in the table due to the nonsignificant number of isolates. “All” indicates all possible phenotypes (S/I/R).