Table 2.
Characterization of eight extended-spectrum cephalosporin (ESC)-resistant Citrobacter spp. strains from dogs and cats.
| Strain | Year | Host | Origin | ST | AmpC Overexpression | ESBLs | qAmpCs | Other β-lactamases | MIC (μg/mL)b | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ACV | CPL | CMZ | CTX | MPM | TET | CHL | AMK | CIP | TMS | |||||||||
| C. freundii (n = 5) | ||||||||||||||||||
| Ci17 | 2016 | Cat | Urine | 18 | + | CMY-117 | TEM-1 | 64/32 | >256 | 64 | 32 | 0.063 | 1 | 16 | 2 | 8 | 8/152 | |
| Ci20 | 2016 | Cat | Urine | 156 * | - | CTX-M-3 | CMY-78-like | TEM-1 | 16/8 | >256 | 16 | 256 | 0.031 | 1 | 8 | 4 | 2 | 0.06/1.19 |
| Ci29 | 2016 | Cat | Urine | 156 * | - | CTX-M-3 | CMY-78-like | TEM-1 | 16/8 | >256 | 8 | >256 | 0.031 | 4 | 16 | 2 | 4 | 0.25/4.75 |
| Ci31 | 2016 | Cat | Urine | 18 | + | CMY-117 | 64/32 | >256 | 64 | 16 | 0.063 | 128 | 8 | 1 | 8 | >64/1216 | ||
| Ci32 | 2016 | Cat | Urine | 156 * | - | CTX-M-3 | CMY-78-like | TEM-1 | 32/16 | >256 | 16 | >256 | 0.031 | 32 | 16 | 8 | 8 | 2/38 |
| C. portucalensis (n = 2) | ||||||||||||||||||
| Ci10 | 2015 | Dog | Urine | NA | + | DHA-1, CMY-37-like |
64/32 | >256 | 64 | 8 | 0.125 | 128 | 128 | 2 | 16 | >64/1216 | ||
| Ci27 | 2016 | Dog | Nasal | NA | + | CMY-13 | 64/32 | >256 | 128 | 32 | 0.063 | 1 | 8 | 4 | 4 | ≤0.03/0.59 | ||
| C. koseri (n = 1) | ||||||||||||||||||
| Ci7 | 2015 | Dog | Urine | NA | NA | DHA-1 | 64/32 | >256 | 64 | 4 | 0.015 | 1 | 8 | 1 | 0.25 | 0.5/9.5 | ||
NA, Not applicable. * ST156 was firstly identified in this study. ACV, amoxicillin–clavulanic acid; CPL, cephalothin; CMZ, cefmetazole; CTX, cefotaxime; MPM, meropenem; TET, tetracycline; CHL. Chloramphenicol; AMK, amikacin; CIP, ciprofloxacin; TMS, trimethoprim–sulfamethoxazole.